ORCID Profile
0000-0001-6254-2372
Current Organisation
University of Adelaide
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Publisher: Wiley
Date: 31-07-2003
DOI: 10.1002/CA.10146
Abstract: Tarsal coalitions (TC) are defined as fibrous (beyond normal ligaments), cartilaginous, or osseous unions of at least two tarsal bones. Most of the clinical studies report the prevalence of TC as <1%, but they disregard the asymptomatic coalitions. Because TC have been associated with pathologic conditions, including degenerative arthritic changes, knowledge of their prevalence has clinical importance. The aim of our study was to establish the prevalence of TC and tarsal joint variants. A total of 114 feet from 62 cadavers (average age = 78 years) without obvious foot pathologies were dissected at the Department of Anatomical Sciences, The University of Adelaide. Ten non-osseous TC in eight subjects were identified: two talocalcaneal and eight calcaneonavicular (occurred twice bilaterally). Variant calcaneonavicular and cuboideonavicular joints were found in 8% and 31% of feet, respectively. Other joint variants included a variable number of talocalcaneal joint surfaces and sesamoid bones. No secondary TC (due to trauma, infections, or neoplasm) were found. Our study demonstrated that the overall prevalence of TC is higher (13%) than previously thought tarsal joint variations (39%) and sesamoid bones (42%) were common as well. The supposed secular increase in the prevalence of TC as well as the high number of anatomical variants could reflect a short-term response to altered life-style or a microevolutionary trend due to relaxed selection.
Publisher: Elsevier BV
Date: 11-2011
DOI: 10.1016/J.INJURY.2011.05.012
Abstract: The aim of the study was to investigate the possible outcomes of intracapsular femoral neck fractures managed non-operatively or with a simple form of internal fixation. We reviewed 30 fractures and their post mortem reports from the Galler collection, a modern pathology reference series. Our investigation revealed unusual appearances of the hip following femoral neck fractures that are not usually seen in modern orthopaedic practice, including previously undescribed acetabularisation of the femur and ankyloses of ununited femoral heads. Appreciation of these appearances and an understanding of how these fractures may progress are important in the current diagnosis and management of delayed presentations, neglected or inadequately fixed subcapital fractures of the femoral neck.
Publisher: Medical Journals Sweden AB
Date: 14-05-2010
Publisher: Elsevier BV
Date: 12-2017
DOI: 10.1016/J.INJURY.2017.10.040
Abstract: To identify and describe the characteristics of existing practices for postoperative weight bearing and management of tibial plateau fractures (TPFs), identify gaps in the literature, and inform the design of future research. Seven electronic databases and clinical trial registers were searched from inception until November 17th 2016. Studies were included if they reported on the surgical management of TPFs, had a mean follow-up time of ≥1year and provided data on postoperative management protocols. Data were extracted and synthesized according to study demographics, patient characteristics and postoperative management (weight bearing regimes, immobilisation devices, exercises and complications). 124 studies were included involving 5156 patients with TPFs. The mean age across studies was 45.1 years (range 20.8-72 60% male), with a mean follow-up of 34.9 months (range 12-264). The most frequent fracture types were AO/OTA classification 41-B3 (29.5%) and C3 (25%). The most commonly reported non-weight bearing time after surgery was 4-6 weeks (39% of studies), with a further 4-6 weeks of partial weight bearing (51% of studies), resulting in 9-12 weeks before full weight bearing status was recommended (55% of studies). Loading recommendations for initial weight bearing were most commonly toe-touch/<10kg (28%), 10kg-20kg (33%) and progressive (39%). Time to full weight bearing was positively correlated with the proportion of fractures of AO/OTA type C (r=0.465, p=0.029) and Schatzker type IV-VI (r=0.614, p<0.001). Similar rates of rigid (47%) and hinged braces were reported (58%), most frequently for 3-6 weeks (43% of studies). Complication rates averaged 2% of patients (range 0-26%) for abnormal varus/valgus and 1% (range 0-22%) for non-union or delayed union. Postoperative rehabilitation for TPFs most commonly involves significant non-weight bearing time before full weight bearing is recommended at 9-12 weeks. Partial weight bearing protocols and brace use were varied. Type of rehabilitation may be an important factor influencing recovery, with future high quality prospective studies required to determine the impact of different protocols on clinical and radiological outcomes.
Publisher: Wiley
Date: 28-11-2017
DOI: 10.1002/JOR.23474
Abstract: Tibial subchondral bone plays an important role in knee osteoarthritis (OA). Microarchitectural characterization of subchondral bone plate (SBP), underlying subchondral trabecular bone (STB) and relationships between these compartments, however, is limited. The aim of this study was to characterize the spatial distribution of SBP thickness, SBP porosity and STB microarchitecture, and relationships among them, in OA tibiae of varying joint alignment. Twenty-five tibial plateaus from end-stage knee-OA patients, with varus (n = 17) or non-varus (n = 8) alignment were micro-CT scanned (17 μm/voxel). SBP and STB microarchitecture was quantified via a systematic mapping in 22 volumes of interest per knee (11 medial, 11 lateral). Significant within-condylar and between-condylar (medial vs. lateral) differences (p < 0.05) were found. In varus, STB bone volume fraction (BV/TV) was consistently high throughout the medial condyle, whereas in non-varus, medially, it was more heterogeneously distributed. Regions of high SBP thickness were co-located with regions of high STB BV/TV underneath. In varus, BV/TV was significantly higher medially than laterally, however, not so in non-varus. Moreover, region-specific significant associations between the SBP thickness and SBP porosity and the underlying STB microarchitecture were detected, which in general were not captured when considering the values averaged for each condyle. As subchondral bone changes reflect responses to local mechanical and biochemical factors within the joint, our results suggest that joint alignment influences both the medial-to-lateral and the within-condyle distribution of force across the tibia, generating corresponding local bony responses (adaptation) of both the subchondral bone plate and underlying subchondral trabecular bone microarchitecture. © 2016 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 35:1927-1941, 2017.
Publisher: Ovid Technologies (Wolters Kluwer Health)
Date: 2022
Abstract: We report a case of acetabular reconstruction for a large defect with pelvic discontinuity that underwent 4 revisions for dislocations over a 3-year period. This allowed assessment of implant stability both on imaging, using measurements on plain radiographs and radiostereometric analysis (RSA) against both ilium and ischium, and direct assessment during each surgery. Only implant stability measured with RSA correlated with intraoperative revision findings. This case underlines the role of RSA in assessing early acetabular implant stability in pelvic discontinuity and the importance of assessing the stability of the implant against both ilium and ischium.
Publisher: Cold Spring Harbor Laboratory
Date: 20-01-2023
DOI: 10.1101/2023.01.18.524641
Abstract: It is unclear if different factors influence osteoarthritis (OA) progression and the changes characterising OA disease in hip and knee. We investigated the difference between hip OA and knee OA at the subchondral bone tissue and cellular level, relative to the degree of cartilage degeneration. Bone s les were collected from 11 patients (aged 70±8 years) undergoing knee arthroplasty and 8 patients (aged 64±12 years) undergoing hip arthroplasty surgery. Bone microstructure, osteocyte-lacunar network and bone matrix vascularity were evaluated using synchrotron micro-CT imaging. S les were additionally examined histologically to determine osteocyte density, viability, and connectivity. After adjustment for donor gender and age, associations between the extent of cartilage degeneration, bone volume fraction [8.7, 95% CI (3.4, 14.1)], trabecular number [1.5, 95% CI (0.8, 2.3)], osteocyte lacunar density [4714.9 95% CI (2079.1, 7350.6)] and trabecular separation [-0.06, 95% CI (0.01, 0.1)] were found in both knee and hip OA. When compared to knee OA, hip OA was characterised by higher trabecular thickness [0.006, 95% CI (-4, 0.01)], larger but less spheric osteocyte lacunae [47.3 95% CI (11.2, 83.4), -0.04 95% CI (-0.6, -0.01), respectively], lower vascular canal density [-22.8 95% CI (-35.4, -10.3)] lower osteocyte density [-84.9 95% CI (-102.4, -67.4)], and less senescent but more apoptotic osteocytes [-2.4 95% CI (-3.6, -1.2), 24.9 95% CI (17.7, 32.1)], respectively. Subchondral bone from hip OA and knee OA exhibits different characteristics at the tissue and cellular levels, suggesting different mechanisms of OA progression between the hip and knee joints.
Publisher: Elsevier BV
Date: 02-2019
DOI: 10.1016/J.MEDENGPHY.2018.12.003
Abstract: Personalised information of knee mechanics is increasingly used for guiding knee reconstruction surgery. We explored use of uniaxial knee laxity tests mimicking Lachman and Pivot-shift tests for quantifying 3D knee compliance in healthy and injured knees. Two healthy knee specimens (males, 60 and 88 years of age) were tested. Six-degree-of-freedom tibiofemoral displacements were applied to each specimen at 5 intermediate angles between 0° and 90° knee flexion. The force response was recorded. Six-degree-of-freedom and uniaxial tests were repeated after sequential resection of the anterior cruciate, posterior cruciate and lateral collateral ligament. 3D knee compliance (C
Publisher: British Editorial Society of Bone & Joint Surgery
Date: 2014
DOI: 10.1302/0301-620X.96B1.31464
Abstract: We investigated the detailed anatomy of the gluteus maximus, gluteus medius and gluteus minimus and their neurovascular supply in 22 hips in 11 embalmed adult Caucasian human cadavers. This led to the development of a surgical technique for an extended posterior approach to the hip and pelvis that exposes the supra-acetabular ilium and preserves the glutei during revision hip surgery. Proximal to distal mobilisation of the gluteus medius from the posterior gluteal line permits exposure and mobilisation of the superior gluteal neurovascular bundle between the sciatic notch and the entrance to the gluteus medius, enabling a wider exposure of the supra-acetabular ilium. This technique was subsequently used in nine patients undergoing revision total hip replacement involving the reconstruction of nine Paprosky 3B acetabular defects, five of which had pelvic discontinuity. Intra-operative electromyography showed that the innervation of the gluteal muscles was not affected by surgery. Clinical follow-up demonstrated good hip abduction function in all patients. These results were compared with those of a matched cohort treated through a Kocher–Langenbeck approach. Our modified approach maximises the exposure of the ilium above the sciatic notch while protecting the gluteal muscles and their neurovascular bundle. Cite this article: Bone Joint J 2014 -B:48–53.
Publisher: Elsevier BV
Date: 07-2017
DOI: 10.1016/J.INJURY.2017.05.024
Abstract: Tibial plateau fractures are complex and the current evidence for postoperative rehabilitation is weak, especially related to the recommended postoperative weight bearing. The primary aim of this study was to investigate if loading in the first 12 weeks of recovery is associated with patient reported outcome measures at 26 and 52 weeks postoperative. We hypothesized that there would be no association between loading and patient reported outcome measures. Seventeen patients, with a minimum of 52-week follow-up following fragment-specific open reduction and internal fixation for tibial plateau fracture, were selected for this retrospective analysis. Postoperatively, patients were advised to load their limb to a maximum of 20kg during the first 6 weeks. Loading data were collected during walking using force platforms. A ratio of limb loading (affected to unaffected) was calculated at 2, 6 and 12 weeks postoperative. Knee Injury and Osteoarthritis Scores were collected at 6, 12, 26 and 52 weeks postoperative. The association between loading ratios and patient reported outcomes were investigated. Compliance with weight bearing recommendations and changes in the patient reported outcome measures are described. Fracture reduction and migration were assessed on plain radiographs. No fractures demonstrated any measurable postoperative migration at 52 weeks. Significant improvements were seen in all patient reported outcome measures over the first 52 weeks, despite poor adherence to postoperative weight bearing restrictions. There were no associations between weight bearing ratio and patient reported outcomes at 52 weeks postoperative. Significant associations were identified between the loading ratio at 2 weeks and knee-related quality of life at six months (R
Publisher: Wiley
Date: 12-07-2016
DOI: 10.1002/JOR.23356
Abstract: A number of different software programs are used to investigate the in vivo wear of polyethylene bearings in total hip arthroplasty. With wear rates below 0.1 mm/year now commonly being reported for highly cross-linked polyethylene (XLPE) components, it is important to identify the accuracy of the methods used to measure such small movements. The aims of this study were to compare the accuracy of current software programs used to measure two-dimensional (2D) femoral head penetration (FHP) and to determine whether the accuracy is influenced by larger femoral heads or by different methods of representing the acetabular component within radiostereometric analysis (RSA). A hip phantom was used to compare known movements of the femoral head within a metal-backed acetabular component to FHP measured radiographically using RSA, Hip Analysis Suite (HAS), PolyWare, Ein Bild Roentgen Analyse (EBRA), and Roentgen Monographic Analysis Tool (ROMAN). RSA was significantly more accurate than the HAS, PolyWare, and ROMAN methods when measuring 2D FHP with a 28 mm femoral head. Femoral head size influenced the accuracy of HAS and ROMAN 2D FHP measurements, EBRA proximal measurements, and RSA measurements in the proximal and anterior direction. The use of different acetabular reference segments did not influence accuracy of RSA measurements. The superior accuracy and reduced variability of RSA wear measurements allow much smaller cohorts to be used in RSA clinical wear studies than those utilizing other software programs. © 2016 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 35:988-996, 2017.
Publisher: British Editorial Society of Bone & Joint Surgery
Date: 04-2017
DOI: 10.1302/0301-620X.99B4.BJJ-2016-0805.R1
Abstract: The purpose of this study was to determine the sensitivity, specificity and predictive values of previously reported thresholds of proximal translation and sagittal rotation of cementless acetabular components used for revision total hip arthroplasty (THA) at various times during early follow-up. Migration of cementless acetabular components was measured retrospectively in 84 patients (94 components) using Ein-Bild-Rontgen-Analyse (EBRA-Cup) in two groups of patients. In Group A, components were recorded as not being loose intra-operatively at re-revision THA (52 components/48 patients) and Group B components were recorded to be loose at re-revision (42 components/36 patients). The mean proximal translation and sagittal rotation were significantly higher in Group B than in Group A from three months onwards (p 0.02). Proximal translation 1.0 mm within 24 months had a positive predictive value (PPV) of 90% and a specificity of 94%, but a sensitivity of 64%. Proximal translation 1.0 mm within the first 24 months correctly identified 76 of 94 (81%) of components to be either loose or not loose. However, ten components in Group B (24%) did not migrate proximally above 1.0 mm within the first 60 months. The high PPV of EBRA-Cup measurements of proximal translation (90%) shows that this can be used in early follow-up to identify patients at risk of aseptic loosening. The absence of proximal translation within the first 60 months indicates a component is not likely to be loose at re-revision THA although it does not exclude late aseptic loosening as a cause of failure. Cite this article: Bone Joint J 2017 -B:465–74.
Publisher: Ovid Technologies (Wolters Kluwer Health)
Date: 11-2012
Publisher: Baishideng Publishing Group Inc.
Date: 2013
Publisher: Elsevier BV
Date: 04-2018
DOI: 10.1016/J.JOCA.2018.01.014
Abstract: To study, in end-stage knee osteoarthritis (OA) patients, relationships between indices of in vivo dynamic knee joint loads obtained pre-operatively using gait analysis, static knee alignment, and the subchondral trabecular bone (STB) microarchitecture of their excised tibial plateau quantified with 3D micro-CT. Twenty-five knee OA patients scheduled for total knee arthroplasty underwent pre-operative gait analysis. Mechanical axis deviation (MAD) was determined radiographically. Following surgery, excised tibial plateaus were micro-CT-scanned and STB microarchitecture analysed in four subregions (anteromedial, posteromedial, anterolateral, posterolateral). Regional differences in STB microarchitecture and relationships between joint loading and microarchitecture were examined. STB microarchitecture differed among subregions (P < 0.001), anteromedially exhibiting highest bone volume fraction (BV/TV) and lowest structure model index (SMI). Anteromedial BV/TV and SMI correlated strongest with the peak external rotation moment (ERM r = -0.74, r = 0.67, P < 0.01), despite ERM being the lowest (by factor of 10) of the moments considered, with majority of ERM measures below accuracy thresholds medial-to-lateral BV/TV ratios correlated with ERM, MAD, knee adduction moment (KAM) and internal rotation moment (|r|-range: 0.54-0.74). When controlling for walking speed, KAM and MAD, the ERM explained additional 11-30% of the variations in anteromedial BV/TV and medial-to-lateral BV/TV ratio (R This preliminary study suggests significant associations between tibial plateau STB microarchitecture and knee joint loading indices in end-stage knee OA patients. Particularly, anteromedial BV/TV correlates strongest with ERM, whereas medial-to-lateral BV/TV ratio correlates strongest with indicators of medial-to-lateral joint loading (MAD, KAM) and rotational moments. However, associations with ERM should be interpreted with caution.
Publisher: Elsevier BV
Date: 07-2019
DOI: 10.1016/J.ARTH.2019.03.003
Abstract: The aim of this study is to assess the outcomes of 52 consecutive Vancouver B2 peri-prosthetic fractures around cemented polished double-tapered stems treated by open reduction and internal fixation in 2 trauma centers in 2 countries. Outcomes included modified Harris Hip Score (mHHS), Harris Pain Score, and return to pre-injury mobility. Fracture healing was assessed implant subsidence measured and complications including re-operations reported. No patient was lost to follow-up. Median patient age at operation was 82 years (range 43-98) Harris pain scores showed minimal pain (median 42, range 10-44) at latest follow-up. Median total subsidence at 1 year was 1.1 mm (range 0-5.4), the majority of which occurred within the cement mantle. No subsequent femoral stem revision was required (median 2.9 years, 0-10) however, there were 3 re-operations: 1 re-operation for pre-existing recurrent dislocation involving head liner exchange and 2 for repeat fixation due to metal fatigue. Two additional fractures occurred below the new plating, requiring further plating whilst still retaining the original stems. Anatomical reduction and open reduction and internal fixation of Vancouver B2 peri-prosthetic fractures should be considered as an appropriate treatment solution for frail elderly patients with a peri-prosthetic fracture around cemented polished double-tapered stems.
Publisher: Ovid Technologies (Wolters Kluwer Health)
Date: 10-2017
DOI: 10.11124/JBISRIR-2016-002949
Abstract: Based on the observation that rehabilitation practices for tibial plateau fractures are inconsistent and lack uniformity in the published literature, this scoping review will seek to identify all relevant studies that have reported on rehabilitation for tibial plateau fractures in order to comprehensively map the characteristics of the practices. This scoping review will then be used to identify commonalities across the included studies in order to identify potential focus questions for subsequent systematic reviews.
Publisher: Elsevier BV
Date: 03-2019
DOI: 10.1016/J.JBIOMECH.2019.01.031
Abstract: Marker-based dynamic functional or regression methods are used to compute joint centre locations that can be used to improve linear scaling of the pelvis in musculoskeletal models, although large errors have been reported using these methods. This study aimed to investigate if statistical shape models could improve prediction of the hip joint centre (HJC) location. The inclusion of complete pelvis imaging data from computed tomography (CT) was also explored to determine if free-form deformation techniques could further improve HJC estimates. Mean Euclidean distance errors were calculated between HJC from CT and estimates from shape modelling methods, and functional- and regression-based linear scaling approaches. The HJC of a generic musculoskeletal model was also perturbed to compute the root-mean squared error (RMSE) of the hip muscle moment arms between the reference HJC obtained from CT and the different scaling methods. Shape modelling without medical imaging data significantly reduced HJC location error estimates (11.4 ± 3.3 mm) compared to functional (36.9 ± 17.5 mm, p = <0.001) and regression (31.2 ± 15 mm, p = <0.001) methods. The addition of complete pelvis imaging data to the shape modelling workflow further reduced HJC error estimates compared to no imaging (6.6 ± 3.1 mm, p = 0.002). Average RMSE were greatest for the hip flexor and extensor muscle groups using the functional (16.71 mm and 8.87 mm respectively) and regression methods (16.15 mm and 9.97 mm respectively). The effects on moment-arms were less substantial for the shape modelling methods, ranging from 0.05 to 3.2 mm. Shape modelling methods improved HJC location and muscle moment-arm estimates compared to linear scaling of musculoskeletal models in patients with hip osteoarthritis.
Publisher: Springer Science and Business Media LLC
Date: 15-10-2013
DOI: 10.1007/S10787-013-0192-6
Abstract: Periprosthetic osteolysis is a serious complication of total hip replacement (THR) in the medium to long term. Although often asymptomatic, osteolysis can lead to prosthesis loosening and periprosthetic fracture. These complications cause significant morbidity and require complex revision surgery. Here, we review advances in our understanding of the cell and tissue response to particles produced by wear of the articular and non-articular surfaces of prostheses. We discuss the molecular and cellular regulators of osteoclast formation and bone resorptive activity, a better understanding of which may lead to pharmacological treatments for periprosthetic osteolysis. We describe the development of imaging techniques for the detection and measurement of osteolysis around THR prostheses, which enable improved clinical management of patients, provide a means of evaluating outcomes of non-surgical treatments for periprosthetic osteolysis, and assist in pre-operative planning for revision surgery. Finally, there have been advances in the materials used for bearing surfaces to minimise wear, and we review the literature regarding the performance of these new materials to date.
Publisher: Elsevier BV
Date: 12-2017
DOI: 10.1016/J.INJURY.2017.10.038
Abstract: Trans arterial embolization (TAE) can stem uncontrolled bleeding associated with pelvic fractures, but is associated with potential complications. This study investigated and compared the early to midterm complications in two patient cohorts: one who did and one who did not undergo TAE. The results of 14 patients who underwent TAE in the resuscitation phase, and then had their pelvic fractures managed non-operatively, the study group (Group 1), were compared with those of a control group (Group 2) of 14 patients matched for age, sex, injury and management, that did not undergo TAE. All patients were examined clinically and answered a questionnaire on bowel and urinary function, pain and limp. Gluteus medius structure and volume were assessed on MRI. The hip girdle muscle function was assessed using a hand held dynamometer, surface electromyography as well as quantitative gait analysis. Seven patients in Group 1 (50%), but none in Group 2, had persistent urological dysfunctions, in the absence of any recognized previous pathology or urologic trauma at the time of injury. No gluteal muscle demonstrated fibrosis or fatty infiltration. The median gluteal muscle volume was not significantly decreased compared with the uninjured side in either group (P=0.421). The muscle strengths of gluteus maximus, gluteus medius, tensor fasciae latae and iliopsoas when compared to the uninjured side were significantly less in Group 1 compared to Group 2. However, no patient had a discernable limp and gait analysis showed no significant differences between the left and right sides in the study and control groups in the gluteal activation timing (p=0.171 and 0.354) and duration (p=0.622 and 0.435). There were no skin complications, and no patient reported any persistent bowel dysfunction. TAE was associated with a high rate of persistent urological dysfunction. TAE could lead to decreased hip muscles strength, however this does not seem to affect gait.
Publisher: Ovid Technologies (Wolters Kluwer Health)
Date: 02-2009
Publisher: Elsevier BV
Date: 07-2016
DOI: 10.1016/J.BONE.2016.04.017
Abstract: Osteocytes are essential regulators of bone homeostasis. However, they are difficult to study due to their location within the bone mineralised matrix. Although several techniques have been published for the isolation of osteocytes from mouse bone, no such technique has been described for human osteocytes. We have therefore developed a protocol for the isolation of osteocytes from human trabecular bone s les acquired during surgery. The cells were digested from the bone matrix by sequential collagenase and ethylenediaminetetraacetic acid (EDTA) digestions and the cells from later digests displayed characteristic dendritic osteocyte morphology when cultured ex vivo. Furthermore, the cells expressed characteristic osteocyte marker genes, such as E11, dentin matrix protein 1 (DMP1), SOST, matrix extracellular phosphoglycoprotein (MEPE) and phosphate regulating endopeptidase homologue, X-linked (PHEX). In addition, genes associated with osteocyte perilacunar remodelling, including matrix metallopeptidase-13 (MMP13), cathepsin K (CTSK) and carbonic anhydrase 2 (CAR2) were expressed. The cells also responded to parathyroid hormone (PTH) by downregulating SOST mRNA expression and to 1α,25-dihydroxyvitamin D3 (1,25D) by upregulating fibroblast growth factor 23 (FGF23) mRNA expression. Therefore, the cells behave in a similar manner to osteocytes in vivo. These cells represent an important tool in enhancing current knowledge in human osteocyte biology.
Publisher: Ovid Technologies (Wolters Kluwer Health)
Date: 20-06-2012
DOI: 10.2106/JBJS.K.00570
Publisher: Ovid Technologies (Wolters Kluwer Health)
Date: 05-2011
Publisher: Springer Science and Business Media LLC
Date: 28-11-2019
DOI: 10.1007/S00276-019-02384-8
Abstract: To quantify the prevalence of complete tibial insertion of the biceps femoris tendon in patients presenting for knee MRI scans. Knee MRI scans over a 4-year period (2014-2018) were accessed at a tertiary referral centre and community-based private practice. A total of 433 scans were reviewed. 30 scans were excluded from the study due to repeat imaging or incomplete coverage of the biceps femoris tendon insertion. Appearances of the distal biceps tendon bony insertion were scrutinized on the remaining 403 scans. Each biceps femoris tendon insertion was classified into one of the four categories-complete fibular insertion, predominant fibular insertion, predominant tibial insertion and complete tibial insertion. Out of the final 403 scans included in the study, five cases of complete tibial insertion of the biceps femoris tendon were identified (just over 1% of the total population). 42 cases were identified as having predominant tibial insertion (10% of the total population). 113 cases had predominantly fibular insertion and 243 cases had complete fibular insertion. Complete anomalous insertion of the biceps femoris tendon on the anterolateral tibia is an uncommon entity. Such an attachment is found in approximately 1% of patients presenting for MRI evaluation of the knee.
Publisher: Springer Science and Business Media LLC
Date: 25-05-2010
DOI: 10.1007/S12024-010-9165-X
Abstract: Juvenile seals are sometimes encountered in waters around South Australia with injuries and/or diseases that require veterinary treatment. Two cases are reported where apparently stable animals died soon after being rescued due to quite disparate conditions. In Case 1 a juvenile male New Zealand fur seal (Arctocephalus forsteri) was found unexpectedly dead in its enclosure. A necropsy examination revealed an emaciated juvenile male with no injuries. The intestine was filled throughout its length with melena stool that was due to heavy infestation of the stomach with roundworms with adjacent gastritis. Death was due to shock from upper gastrointestinal blood loss secondary to parasitosis. In Case 2 a second juvenile male New Zealand fur seal (Arctocephalus forsteri) also died unexpectedly in its enclosure. It had been listless with loud respirations since capture. At necropsy there was no blood around the head, neck or mouth, and no acute external injuries were identified. An area of induration was, however, present over the snout with fragmentation of underlying bones. The maxilla was freely mobile and CT scanning revealed multiple comminuted fractures of the adjacent facial skeleton. Examination of the defleshed skull showed fragmentation of the facial skeleton with roughening of bones in keeping with osteomyelitis. Death was attributed to sepsis from osteomyelitis of a comminuted midfacial fracture. These cases demonstrate two unusual and occult conditions that may be present in recently retrieved juvenile fur seals. Failure to establish the correct diagnosis rapidly may result in death soon after capture. The usefulness of imaging techniques such as CT scanning in delineating underlying injuries prior to necropsy is clearly demonstrated.
Publisher: Wiley
Date: 29-05-2020
DOI: 10.1002/JOR.24716
Publisher: Ovid Technologies (Wolters Kluwer Health)
Date: 12-11-2019
DOI: 10.1097/CORR.0000000000000571
Abstract: The Bernese periacetabular osteotomy (PAO) is a complex surgical procedure with a substantial learning curve. Although larger hospital and surgeon procedure volumes have recently been associated with a lower risk of complications, in geographically isolated regions, some complex operations such as PAO will inevitably be performed in low volume. A continuous structured program of distant mentoring may offer benefits when low numbers of PAOs are undertaken, but this has not been tested. We sought to examine a structured, distant-mentorship program of a low-volume surgeon in a geographically remote setting. The purposes of this study were (1) to identify the clinical results of PAO performed in a remote-mentorship program, as determined by patient-reported outcome measures and complications of the surgery (2) to determine radiographic results, specifically postoperative angular corrections, hip congruity, and progression of osteoarthritis and (3) to determine worst-case analysis of PAO survivorship, defined as nonconversion to THA, in a regionally isolated cohort of patients with a high rate of followup. Between August 1992 and August 2016, 85 PAOs were undertaken in 72 patients under a structured, distant-mentorship program. The patients were followed for a median of 5 years (range, 2-25 years). There were 18 males (21 hips) and 54 females (64 hips). The median age of the patients at the time of surgery was 26 years (range, 14-45 years). One patient was lost to followup (two PAOs) and one patient died as a result of an unrelated event. Patient-reported outcome measures and complications were collected through completion of patient and doctor questionnaires and clinical examination. Radiographic assessment of angular correction, joint congruity, and osteoarthritis was undertaken using standard radiology software. PAO survivorship was defined as nonconversion to THA and is presented using worst-case analysis. The loss-to-followup quotient—number of patients lost to followup ided by the number of a patients converted to THA—was calculated to determine quality of followup and reliability of survivorship data. The median preoperative Harris hip scores of 58 (range, 20-96) improved postoperatively to 78 (range, 33-100), 86 (range, 44-100), 87 (range, 55-97), and 80 (range, 41-97) at 1, 5, 10, and 14 years, respectively. Sink Grade III complications at 12 months included four relating to the PAO and one relating to the concomitant femoral procedure. The median lateral center-edge angle correction achieved was 22° (range, 3°-50°) and the median correction of acetabular index was 19° (range, 3°-37°). Osteoarthritis progressed from a preoperative mean Tönnis grade of 0.6 (median, 1 range, 0-2) to a postoperative mean of 0.9 (median, 1 range, 0-3). Six hips underwent conversion to THA: five for progression of osteoarthritis and one for impingement. At 12-year followup, survivorship of PAO was 94% (95% confidence interval [CI], 85%-98%) and survivorship with worst-case analysis was 90% (95% CI, 79%-96%). The loss-to-followup quotient for this study was low, calculated to be 0.3. When PAO is performed using a structured process of mentoring under the guidance of an expert, one low-volume surgeon in a geographically isolated region achieved good patient-reported outcomes, a low incidence of complications at 12 months, satisfactory radiographic outcomes, and high survivorship. A structured distant-mentorship program may be a suitable method for initially learning and continuing to perform low-volume complex surgery in a geographically isolated region. Level IV, therapeutic study.
Publisher: American Society for Microbiology
Date: 02-05-2018
Abstract: Periprosthetic joint infection (PJI) is a potentially devastating complication of orthopedic joint replacement surgery. PJI with associated osteomyelitis is particularly problematic and difficult to cure. Whether viable osteocytes, the predominant cell type in mineralized bone tissue, have a role in these infections is not clear, although their involvement might contribute to the difficulty in detecting and clearing PJI. Here, using Staphylococcus aureus , the most common pathogen in PJI, we demonstrate intracellular infection of human-osteocyte-like cells in vitro and S. aureus adaptation by forming quasi-dormant small-colony variants (SCVs). Consistent patterns of host gene expression were observed between in vitro -infected osteocyte-like cultures, an ex vivo human bone infection model, and bone s les obtained from PJI patients. Finally, we confirm S. aureus infection of osteocytes in clinical cases of PJI. Our findings are consistent with osteocyte infection being a feature of human PJI and suggest that this cell type may provide a reservoir for silent or persistent infection. We suggest that elucidating the molecular/cellular mechanism(s) of osteocyte-bacterium interactions will contribute to better understanding of PJI and osteomyelitis, improved pathogen detection, and treatment. IMPORTANCE Periprosthetic joint infections (PJIs) are increasing and are recognized as one of the most common modes of failure of joint replacements. Osteomyelitis arising from PJI is challenging to treat and difficult to cure and increases patient mortality 5-fold. Staphylococcus aureus is the most common pathogen causing PJI. PJI can have subtle symptoms and lie dormant or go undiagnosed for many years, suggesting persistent bacterial infection. Osteocytes, the major bone cell type, reside in bony caves and tunnels, the lacuno-canalicular system. We report here that S. aureus can infect and reside in human osteocytes without causing cell death both experimentally and in bone s les from patients with PJI. We demonstrate that osteocytes respond to infection by the differential regulation of a large number of genes. S. aureus adapts during intracellular infection of osteocytes by adopting the quasi-dormant small-colony variant (SCV) lifestyle, which might contribute to persistent or silent infection. Our findings shed new light on the etiology of PJI and osteomyelitis in general.
Publisher: Medical Journals Sweden AB
Date: 10-10-2014
Publisher: Ovid Technologies (Wolters Kluwer Health)
Date: 08-2016
DOI: 10.1097/BOT.0000000000000545
Abstract: The superior gluteal neurovascular bundle is at risk of injury in certain types of acetabular fractures and the associated surgery. This article describes the versatility of an extended posterior approach, previously described for complex revision total hip replacement (the Adelaide approach) and for the treatment of acetabular fractures that allows a wide exposure of the ilium through identification, protection, and mobilization of the superior gluteal neurovascular bundle.
Publisher: Elsevier BV
Date: 02-2019
Publisher: Public Library of Science (PLoS)
Date: 26-09-2019
Publisher: Wiley
Date: 12-2001
DOI: 10.1046/J.1469-7580.2001.19960717.X
Abstract: The aim of this study was to investigate the risk and to analyse the significance of laceration of the sural and superficial fibular nerves during the surgical approach to the lateral malleolus. The sural and the superficial fibular nerves, and their branches were dissected under x 3 magnifying lenses in 68 embalmed leg-ankle-foot specimens. The specimens were measured, drawn and photographed. In 35% of specimens the superficial fibular nerve branched before piercing the crural fascia, and in all these specimens the medial dorsal cutaneous nerve of the foot was located in the anterior compartment while the intermediate dorsal cutaneous nerve of the foot was located in the lateral compartment. In 35% of specimens the intermediate dorsal cutaneous nerve of the foot was absent or did not innervate any toe. The deep part of the superficial fibular nerve was in contact with the intermuscular septum. Its superficial part was parallel with the lateral malleolus when the nerve pierced the fascia more proximally and oblique to the lateral malleolus when the nerve pierced the fascia distally. In one case the intermediate dorsal cutaneous nerve of the foot was in danger of laceration during a subcutaneous incision to the lateral malleolus. In 7 cases (10%) the sural nerve overlapped or was tangent to the tip of the malleolus. Malleolar nerve branches were identified in 76% of the cases (in 28% from both sources). The sural nerve supplies the lateral 5 dorsal digital nerves in 40% of cases. Our study indicates that during the approach to the lateral malleolus there is a high risk of laceration of malleolar branches from both the sural and the superficial fibular nerves. There is less risk of damage to the main trunk of these nerves, but the 10% chance of laceration of sural nerve at the tip of the malleolus is significant. As the sural nerve supplies the superficial innervation to the lateral half of the foot and toes in 40% of cases, the risk of its laceration is even more important than indicated by the common anatomical teaching.
Publisher: Elsevier BV
Date: 02-2019
DOI: 10.1016/J.INJURY.2018.10.029
Abstract: The purpose of this study is to analyze posteromedial fragment morphology using two-dimensional computed tomography fracture mapping and to compare posteromedial fragment morphology in various Schatzker type tibial plateau fractures. One hundred twenty-seven consecutive AO/OTA B- and C-type tibial plateau fractures were retrospectively analyzed using 2DCT fracture mapping. The posteromedial articular fracture angle and articular surface areas of all fractures with posteromedial fragments were calculated. Based on biomechanical studies, posteromedial fragments with coronal fracture angles >68° were considered amenable for anterolateral stabilization with standardized plating. Kruskall-Wallis non-parametric test was used for statistical comparison of morphological features of posteromedial fragments between the various Schatzker types. Forty-seven out of 127 tibial plateau fractures included a posteromedial fragment. The mean posteromedial articular fracture angle was 44° (range: 2°-90 Posteromedial fragments commonly occur not only in Schatzker type V and VI, but also in Schatzker type IV tibial plateau fractures. Eighty-five percent of tibial plateau fractures with a posteromedial fragment may benefit from non-standard customized lateral plating, or may require an additional medial or posterior surgical approach for fracture-specific fixation to optimize screw purchase and biomechanical stability.
Publisher: Ovid Technologies (Wolters Kluwer Health)
Date: 03-2015
Publisher: Cold Spring Harbor Laboratory
Date: 04-11-2020
DOI: 10.1101/2020.11.02.365866
Abstract: Neck of femur (NOF) fracture is a prevalent fracture type amongst the ageing and osteoporotic populations, commonly requiring total hip replacement (THR) surgery. Increased fracture risk has also been associated with Alzheimer disease (AD) in the aged. Here, we sought to identify possible relationships between the pathologies of osteoporosis and dementia by analysing bone expression of neurotropic or dementia-related genes in patients undergoing THR surgery for NOF fracture. Femoral bone s les from 66 NOF patients were examined for expression of the neurotropic genes amyloid precursor protein ( APP ), APP-like protein-2 ( APLP2 ), Beta Secretase Cleaving Enzyme-1 ( BACE1 ) and nerve growth factor (NGF). Relationships were examined between the expression of these and of bone regulatory genes, systemic factors and bone structural parameters ascertained from plain radiographs. We found strong relative levels of expression and positive correlations between APP, APLP2, BACE1 and NGF levels in NOF bone. Significant correlations were found between APP, APLP2, BACE1 mRNA levels and bone remodelling genes TRAP, RANKL , and the RANKL:OPG mRNA ratio, indicative of potential functional relationships at the time of fracture. Analysis of the whole cohort, as well as non-dementia and dementia sub-groups, revealed structural relationships between APP and APLP2 mRNA expression and lateral femoral cortical thickness. These findings suggest that osteoporosis and AD may share common molecular pathways of disease progression, perhaps explaining the common risk factors associated with these diseases. The observation of a potential pathologic role for AD-related genes in bone may also provide alternative treatment strategies for osteoporosis and fracture prevention.
Publisher: Institute of Electrical and Electronics Engineers (IEEE)
Date: 07-2022
Publisher: Ovid Technologies (Wolters Kluwer Health)
Date: 07-2013
Publisher: Elsevier BV
Date: 03-2018
DOI: 10.1016/J.INJURY.2018.01.025
Abstract: Classification systems such as the Schatzker and AO/OTA have been proposed for standardised assessment of tibial plateau fractures and to guide clinical decision making. However, there has been no comprehensive literature review of all classification systems for tibial plateau fractures, including assessment of their reliability. The aim of this systematic review was to identify and appraise previously established classification systems for tibial plateau fractures and determine their reliability for fracture classification. Six databases were searched from inception until October 2016. Classification systems for tibial plateau fractures were identified. No restriction was placed on imaging modality (plain film X-ray, CT, MRI). Data synthesis was performed to identify common features of the systems, their prevalence within the literature and studies of intra and inter-rater reliability of fracture classification using Kappa coefficient (κ). Thirty-eight classification systems were identified, five of which were a sub-classification of a single fracture type from a previous tool. The Schatzker and AO/OTA classification systems were the most commonly reported. Of the tools identified only five have been tested for inter and intra-observer reliability (Schatzker, AO/OTA, Duparc, Hohl and Luo). Reliability of more simplistic classification systems, such as that by Luo et al. (three-column) was typically high (intra-κ = 0.67-0.81, inter-κ = 0.71-0.87), but with the disadvantage of providing less information on fracture patterns and morphology. Intra and inter-observer reliability using plain film X-ray was frequently moderate (κ = 0.40-0.60), with 2D and 3D CT typically improving reliability of classification. Only 11 of the 32 complete classification systems identified association of fracture classification with clinical outcome. Frequently used systems for classification of tibial plateau fractures display moderate intra and inter-observer reliability. More sophisticated imaging modalities such as 2D and 3D CT typically improve reliability estimates. Using fracture classification based on imaging findings to predict clinical outcome was not a commonly reported goal of newly developed systems. More detailed assessment of fracture patterns and morphology, in conjunction with information on surgical fixation, may be desirable for predicting outcomes and to guide clinical decision making.
Publisher: Elsevier BV
Date: 06-2012
DOI: 10.1016/J.ARTH.2011.09.012
Abstract: We examined the sensitivity and accuracy of measuring osteolysis around total knee arthroplasty (TKA) on radiographs, computed tomography (CT), and magnetic resonance imaging (MRI) in a cadaver model. Fifty-four simulated osteolytic defects ranging from 0.7 to 14 cm(3) were created in 6 cadaver knees implanted with either a cemented or an uncemented TKA. Three blinded investigators assessed the presence, location, and volume of defects on radiographs and CT and MRI scans with metal reduction protocols. Both CT and MRI had significantly higher sensitivities and specificities than did plain radiographs (P < .005). Overall, there was no difference in the accuracy of defect volume measurements between CT and MRI (P = .574). This study demonstrates the limitations of radiographs and the high sensitivity and specificity of both CT and MRI in assessing osteolysis around TKA.
Publisher: Cold Spring Harbor Laboratory
Date: 29-09-2021
DOI: 10.1101/2021.09.27.21264218
Abstract: The primary aim of this study was to assess the effect of time to surgery on fracture reduction, assessed as residual articular step, in cases of tibial plateau fracture (TPF). The secondary aim was to assess the effect of pre-operative demographics and residual articular step on patient reported outcomes (PROMs) following TPF. Between 2006 and 2017 all surgically treated TPF patients managed by a single surgeon at our institution were prospectively consented for the study of fracture outcomes. Timing to surgical intervention, reduction of articular step, age, gender, medical background, fracture classification, mechanism of injury and PROMs (Lysholm Scores and Knee Injury and Osteoarthritis Outcome Scores (KOOS)) were recorded and analysed. Reduction of articular step, defined as mm, was assessed by a single blinded examiner using measurements on plain radiographs on PACS. One hundred seventeen patients were enrolled, 52 with Schatzker II, four with Schatzker IV and 61 with Schatzker VI fractures. Patients were followed-up to a mean time of 3.9 years. The ability to achieve fracture reduction was negatively influenced by time to theatre with the odds of achieving reduction decreasing 17% each day post-injury (p = 0.002). An increased time to theatre was associated with reduced Lysholm scores at the one-year mark (p = 0.01). The ability to achieve fracture reduction did not influence PROMs within the study period. Delay in surgical fixation negatively affects fracture reduction in TPF and may delay recovery. However, residual articular step did not influence the investigated PROMs in the cohort investigated over the mid-term (mean of 3.9 years).
Publisher: Wiley
Date: 20-02-2020
DOI: 10.1002/JOR.24623
Publisher: Elsevier BV
Date: 2014
DOI: 10.1016/J.MEDENGPHY.2013.09.003
Abstract: This study compared the initial viscoelastic properties of a segmental tibial defect stabilized with intramedullary nailing and impaction bone grafting to that of a transverse fracture stabilized with intramedullary nailing. Seven sheep tibiae were tested in compression (1000N), bending and torsion (6Nm) in a six degree-of-freedom hexapod robot. Tests were repeated across three groups: intact tibia (Intact), transverse fracture stabilized by intramedullary nailing (Fracture), and segmental defect stabilized with a nail and impaction bone grafting (Defect). Repeated measures ANOVA on the effect of group on stiffness hase angle were conducted for each loading direction. The Intact group was significantly stiffer than the Fracture and Defect groups in bending and torsion (p 0.246 for all loading directions) for stiffness hase angle. In compression and bending, phase angles were significantly greater for the Fracture and Defect groups compared to Intact (p<0.025), with no significant differences between groups in torsion (p=0.13). Sensitivity analyses conducted between the Fracture and Defect group differences found that they were not of clinical significance. The initial properties of a segmental defect stabilized with intramedullary nailing and impaction bone grafting was not clinically significantly different to that of a transverse fracture stabilized with intramedullary nailing.
Publisher: Wiley
Date: 11-2008
DOI: 10.1002/CA.20722
Publisher: Springer Science and Business Media LLC
Date: 23-01-2015
Publisher: Wiley
Date: 12-1997
DOI: 10.1002/(SICI)1097-0185(199712)249:4<506::AID-AR10>3.0.CO;2-S
Publisher: Wiley
Date: 03-2003
Publisher: Elsevier BV
Date: 04-2014
DOI: 10.1016/J.INJURY.2013.11.035
Abstract: Tibial plateau fractures (TPFs) are an independent, non-modifiable risk factor for surgical site infections (SSIs). Current antero-lateral approaches to the knee dissect through the anterior tibial angiosome (ATA), which may contribute to a higher rate of SSIs. The aim of this study was to develop an angiosome-sparing antero-lateral approach to allow reduction and fixation of lateral TPFs and to investigate its feasibility in a consecutive cohort. Twenty cadaveric knees were dissected to define the position of the vessels supplying the ATA from the lateral tibial condyle to the skin perforators. Based on these results, an angiosome-sparing surgical approach to treat lateral TPFs was developed. Fifteen consecutive patients were subsequently treated through this approach. Clinical outcomes included assessment of SSI and Lysholm score. Fracture healing and stability were assessed using the Rasmussen score and radiostereometric analysis (RSA). At the latest follow-up between 1 and 4 years, there was no report of SSI. Nine patients (60%) had good or excellent Lysholm scores. The mean Rasmussen score at final follow-up was 17 (median 18, range 14-18) with 10 patients (66%) graded as excellent. Fracture fragment migration measured using RSA was below 2mm in all cases. This study has demonstrated that an angiosome-sparing antero-lateral approach to the lateral tibial plateau is feasible. Adequate stability of these fracture types was achieved by positioning a buttress plate away from the bone and superficial to the regional fascial layer as an 'internal-external fixator'. The angiosome-sparing approach developed was able to be used in a prospective cohort and the clinical results to date are encouraging. Future clinical studies need to investigate the potential benefits of this surgical approach when compared with the previously described antero-lateral approaches.
Publisher: Elsevier BV
Date: 11-2013
DOI: 10.1016/J.INJURY.2013.04.024
Abstract: Lateral tibial plateau fractures that are located posterolaterally are difficult to reduce through an anterolateral surgical approach because of the lack of direct visualisation of the fracture. This study compared the results of unicondylar posterolateral tibial plateau fractures in two patient cohorts: one treated through a posterolateral direct approach and the other through an anterolateral indirect approach. All nine patients admitted to our hospital, a tertiary care, urban, public hospital in Australia, from 2007 to 2010 with unicondylar posterolateral tibial plateau fractures were treated through a direct posterolateral transfibular approach and prospectively studied. All eight patients admitted from 2004 to 2007 with unicondylar posterolateral tibial plateau fractures were treated through an indirect anterolateral approach and retrospectively reviewed. Fracture reduction and maintenance of reduction were assessed radiographically over 2 years. Knee function was assessed clinically and using the Lysholm score. Fractures managed through a direct posterolateral transfibular approach were reduced with no measurable articular step on standard radiography and had no loss of reduction over time. By contrast, fractures treated through an indirect anterolateral approach had a median postoperative articular step of 5.5mm (interquartile range=4.5). These displacements worsened over time in six of the eight patients. At 2 years, patients treated through a direct approach had significantly better Lysholm scores than those treated through an indirect approach. This study suggests that a direct posterolateral transfibular approach to unicondylar posterolateral tibial plateau fractures results in improved reduction, stabilisation and functional outcomes at early follow-up compared to an indirect anterolateral approach.
Publisher: Ovid Technologies (Wolters Kluwer Health)
Date: 04-2020
DOI: 10.2106/JBJS.RVW.19.00170
Abstract: » Radiostereometric analysis (RSA) studies of acetabular component migration following revision total hip arthroplasty (THA) have a large variation in their methodology and reporting of results, and, therefore, they may not be directly comparable. Standardization of RSA reporting is recommended. » In our review of RSA studies, there was a trend for cemented acetabular components to have larger amounts of early proximal migration than uncemented acetabular components. Results regarding cemented and uncemented components should be reported separately. » Cohorts that addressed larger acetabular defects were associated with a larger amount of early migration. » Reporting the migration result at 1 and 2 years postoperatively may enable earlier identification of poorly performing implants.
Publisher: Wiley
Date: 17-07-2021
DOI: 10.1002/JOR.25140
Abstract: Biomechanical factors (e.g., joint loading) have a significant role in the progression of osteoarthritis (OA). However, some relationships between in vivo joint loading indices and tibial cartilage thickness are conflicting. This study investigated relationships between pre‐operative in vivo external knee joint moments, joint alignment and regional tibial cartilage thickness using micro‐CT in subjects with end‐stage knee OA. Tibial plateaus from 25 patients that underwent knee replacement for OA were micro‐CT scanned (17 µm/voxel). Prior to surgery, subjects underwent gait analysis to calculate external knee moments. The mechanical axis deviation (MAD) was obtained from pre‐operative radiographs. Cartilage thickness (Cart.Th) was analyzed from micro‐CT images, in anteromedial, anterolateral, posteromedial and posterolateral subregions of interest. Medial‐to‐lateral Cart.Th ratios were also explored. Relationships between Cart.Th and joint loading indices were examined using Pearson's correlations. Significant correlations were found between Cart.Th and joint loading indices, positive anteromedially with the first peak knee adduction moment ( r = 0.55, p 0.01) and external rotation moment (ERM r = 0.52, p 0.01), and negative with MAD ( r = −0.76, p 0.001). In the lateral regions, these correlations had opposite signs. The medial‐to‐lateral Cart.Th ratio correlated strongly with ERM ( r = 0.63, p = 0.001) and MAD ( r = −0.75, p 0.001). Joint loading indices correlated with regional cartilage thickness values and their medial‐to‐lateral ratios in end‐stage knee OA subjects, with higher regional loads corresponding to thinner cartilage. These relationships have the opposite sign compared to the subchondral bone microarchitecture found in our previous study on the same specimens, which may suggest a complementary bone–cartilage interplay in response to loading.
Publisher: Elsevier BV
Date: 04-2014
DOI: 10.1016/J.ARTH.2013.08.015
Abstract: This study investigated the variability of os coxae's volume and linear morphometry in 50 dry adult bones. There was a wide variability, with coefficients of variation exceeding 30%, of the bones' volumes (mean 142 ml, range 80 to 300 ml) and distances between the acetabular rim and the horizontal plane through the sciatic notch (mean 10.6 mm, range -7 to 19 mm). The smallest width of the ilium ranged between 3 and 9 mm at a level between 1.5 and 4 cm above the acetabulum. The volume of os coxae correlated with the acetabular diameter (r = 0.79), the height of os coxae (r = 0.88) and antero-posterior length of the ilium at mid-acetabular level (r = 0.70). Knowledge of the variability of os coxae may be useful during preoperative planning in primary and revision hip arthroplasty.
Publisher: Elsevier BV
Date: 03-2019
DOI: 10.1016/J.ACTBIO.2019.01.047
Abstract: Periprosthetic osteolysis is a major cause of implant failure in total hip replacements. Aseptic loosening caused by osteolytic lesions is associated with the production of bioactive wear particles from the articulations of implants. Wear particles infiltrate the surrounding tissue of implants, promoting inflammation as well as bone resorption. Osteocytes have been shown to both regulate physiological osteoclastogenesis and directly remodel their perilacunar bone matrix by the process of osteocytic osteolysis. We hypothesise that osteocytes respond to wear debris of orthopaedic implant materials by adopting a pro-catabolic phenotype and thus contribute to periprosthetic osteolysis through the known pathways of bone loss. Osteocyte responses to particles derived from clinically relevant materials, ultra-high molecular weight polyethylene (UHMWPE), highly cross-linked polyethylene (XLPE) and metal alloys, Ti6Al4V and CoCrMo, were examined in vitro in human primary osteocyte-like cultures. Osteocyte-like cells exposed to both polyethylene and metal wear particle types showed upregulated expression of catabolic markers associated with osteocytic osteolysis, MMP13, carbonic anhydrase 2 (CA2) and cathepsin K (CTSK). In addition, pro-osteoclastogenesis markers RANKL and M-CSF were induced, as well as the expression of pro-inflammatory cytokines, IL-6 and TNFα, albeit with different kinetics. These findings suggest a previously unrecognised action of wear particles of multiple orthopaedic materials on osteocytes, and suggest a multifaceted role for osteocytes in periprosthetic osteolysis. STATEMENT OF SIGNIFICANCE: This study addresses periprosthetic osteolysis, a major clinical problem leading to aseptic loosening of orthopaedic implants. It is well accepted that wear particles of polyethylene and of other implant materials stimulate the activity of bone resorbing osteoclasts. Our recent work provided evidence that commercial particles of ultra-high molecular weight polyethylene (UHMWPE) stimulated osteocytes to adopt a bone catabolic state. In this study we demonstrate for the first time that particles derived from materials in clinical use, conventional UHMWPE, highly cross-linked polyethylene (XLPE), and Ti6Al4V and CoCrMo metal alloys, all stimulate human osteocyte activities of osteocyte-regulated osteoclastogenesis, osteocytic osteolysis, proinflammatory responses, osteocyte apoptosis, albeit to varying extents. This study provides further mechanistic insight into orthopaedic wear particle mediated bone disease in terms of the osteocyte, the most abundant and key controlling cell type in bone.
Publisher: Springer International Publishing
Date: 2016
Publisher: Elsevier BV
Date: 04-2017
DOI: 10.1016/J.ARTH.2016.11.031
Abstract: The risk of revision following primary total hip arthroplasty (THA) is increased in young patients who undergo THA for pathologies other than primary osteoarthritis. We report the results of primary THA performed with cemented polished stems in patients aged 40 years and younger for pathologies other than primary osteoarthritis. We investigated 52 patients (65 hips) who underwent primary THA for secondary osteoarthritis with a cemented tapered polished stem between 1990 and 2007. Clinical and radiographic outcomes, available in 46 patients (57 hips), included the Harris Hip Scores, Societe Internationale de Chirurgie Orthopedique et de Traumatologie activity, patient satisfaction, stem survival and reoperations, and assessment of prosthesis-cement-bone radiolucencies, osteolysis, and femoral bone deficiencies. Median patient age was 34 years (16-40) and follow-up was 14 years (mean 13, range 5-22). Stem survival to the endpoint revision for loosening was 100% and to the endpoint revision for any reason, excluding infection was 88% (95% confidence interval 78-98) at 16 years. No stem was revised for aseptic loosening. Nine stems were revised for other reasons. Radiographically, one stem was definitely loose at 16 years. The median patient Harris pain score improved from marked pain to no pain at latest follow-up. Patient activity level improved, albeit minimally, for 8 years after surgery. At latest follow-up, 98% of the patients remained satisfied with their surgery. Primary THA with a cemented polished stem shows excellent results in young patients with pathology other than primary osteoarthritis. In addition, the stem design facilitates cement within cement exchange and therefore preservation of proximal femoral bone stock at revision surgery.
Publisher: Wiley
Date: 13-07-2018
DOI: 10.1002/JOR.24057
Abstract: We investigated if time between injury and surgery affects cancellous bone properties in patients suffering tibial plateau fractures (TPF), in terms of structural integrity and gene expression controlling bone loss. A cohort of 29 TPF, operated 1–17 days post‐injury, had biopsies from the fracture and an equivalent contralateral limb site, at surgery. S les were assessed using micro‐computed tomography and real‐time RT‐PCR analysis for the expression of genes known to be involved in bone remodeling and fracture healing. Significant decreases in the injured vs control side were observed for bone volume fraction (BV/TV, −13.5 ± 6.0%, p = 0.011), trabecular number (Tb.N, −10.5 ± 5.9%, p = 0.041) and trabecular thickness (Tb.Th, −4.6 ± 2.5%, p = 0.033). Changes in these parameters were more evident in patients operated 5–17 days post‐injury, compared to those operated in the first 4 days post‐injury. A significant negative association was found between Tb.Th ( r = −0.54, p 0.01) and BV/TV ( r = −0.39, p 0.05) in relation to time post‐injury in the injured limb. Both BV/TV and Tb.Th were negatively associated with expression of key molecular markers of bone resorption, CTSK , ACP5 , and the ratio of RANKL : OPG mRNA. These structure/gene expression relationships did not exist in the contralateral tibial plateau of these patients. This study demonstrated that there is a significant early time‐dependent bone loss in the proximal tibia after TPF. This bone loss was significantly associated with altered expression of genes typically involved in the process of osteoclastic bone resorption but possibly also bone resorption by osteocytes. The mechanism of early bone loss in such fractures should be a subject of further investigation. © 2018 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 36:2865–2875, 2018.
Publisher: British Editorial Society of Bone & Joint Surgery
Date: 04-2017
DOI: 10.1302/0301-620X.99B4.BJJ-2016-0804.R1
Abstract: This study aimed to determine the diagnostic performance of radiographic criteria to detect aseptic acetabular loosening after revision total hip arthroplasty (THA). Secondary aims were to determine the predictive values of different thresholds of migration and to determine the predictive values of radiolucency criteria. Acetabular component migration to re-revision was measured retrospectively using Ein-Bild-Rontgen-Analyse (EBRA-Cup) and manual measurements (Sutherland method) in two groups: Group A, 52 components (48 patients) found not loose at re-revision and Group B, 42 components (36 patients) found loose at re-revision between 1980 and 2015. The presence and extent of radiolucent lines was also assessed. Using EBRA, both proximal translation and sagittal rotation were excellent diagnostic tests for detecting aseptic loosening. The area under the receiver operating characteristic (ROC) curves was 0.94 and 0.93, respectively. The thresholds of 2.5 mm proximal translation or 2° sagittal rotation (EBRA) in combination with radiolucency criteria had a sensitivity of 93% and specificity of 88% to detect aseptic loosening. The sensitivity, specificity, positive predictive value and negative predictive value (NPV) of radiolucency criteria were 41%, 100%, 100% and 68% respectively. Manual measurements of both proximal translation and sagittal rotation were very good diagnostic tests. The area under the ROC curve was 0.86 and 0.92 respectively. However, manual measurements had a decreased specificity compared with EBRA. Radiolucency criteria had a poor sensitivity and NPV of 41% and 68% respectively. This study shows that EBRA and manual migration measurements can be used as accurate diagnostic tools to detect aseptic loosening of cementless acetabular components used at revision THA. Radiolucency criteria should not be used in isolation to exclude loosening of cementless acetabular components used at revision THA given their poor sensitivity and NPV. Cite this article: Bone Joint J 2017 -B:458–64.
Publisher: Elsevier BV
Date: 05-2013
DOI: 10.1016/J.ARTH.2012.09.021
Abstract: A systematic literature review was conducted to identify the best available evidence describing the differences in clinical outcome associated with the different methods of total knee replacement (TKR) fixation. Randomized trials published between 1980 and January 2011 comparing differences in clinical outcome scores between groups allocated to either cemented or uncemented fixation for TKR were included. Nine of the 11 studies included in the review reported no significant differences in clinical outcomes between groups with either cemented or uncemented prosthesis components. Critical appraisal of methodological bias revealed consistent shortcomings in study design and execution. It is apparent that more rigorous studies with longer follow-up periods are required to verify which method of fixation may be preferable in enhancing clinical outcomes.
Publisher: Wiley
Date: 10-2008
DOI: 10.1002/CA.20697
Abstract: Pelvic external fixators have a high rate of reported complications, most of which relate to pin placement. In this descriptive study, we analyzed the morphology of the ilium in cadaveric specimens and compared these with the measures obtained from normal human pelvic computer tomograph scans, and how these related to each of the three basic configurations of pin positioning for the external fixation of a pelvis: anterosuperior (Slätis type), anteroinferior (supra-acetabular), and subcristal. The irregular shape and size of the iliac wing and the abdominal wall overlying the pin's insertion site could hinder accurate placement of anterosuperior pins. Potential disadvantages of the use of anteroinferior pins was found related to the deep location of the anterior inferior iliac spine, interference with the hip flexion area, risk of hip joint penetration, and the variable obliquity of the ilium. As subcristal pins are positioned between two superficial bony landmarks of the iliac crest, our findings suggest that they are more likely to have a correct placement and avoid complications.
Publisher: Elsevier BV
Date: 10-2017
DOI: 10.1016/J.JOCA.2017.06.001
Abstract: To (1) stratify patient subgroups according to their distinct walking gait patterns in end-stage knee osteoarthritis (OA) (2) compare measures of joint loading and proximal tibia subchondral trabecular bone (STB) microarchitecture among these gait subgroups. Twenty-five knee OA patients undergoing total knee arthroplasty (TKA) had pre-operative gait analysis. Following surgery, excised tibial plateaus were micro-CT-scanned and STB microarchitecture analysed in four tibial condylar regions of interest. Peak knee moments were input to k-means cluster analysis, to identify subgroups with homogeneous gait patterns. Joint loading and STB microarchitecture parameters were compared among gait subgroups (Kruskal-Wallis, Bonferroni-corrected Mann-Whitney U tests). Three gait subgroups were revealed: biphasics (n = 7), flexors (n = 9), counter-rotators (n = 9). Peak knee adduction moment (KAM) and KAM impulse were significantly higher (P < 0.05) in biphasics than in flexors and counter-rotators (KAM = -0.65, -0.40 and -0.21 Nm/kg, respectively), suggesting a higher medial-to-lateral tibiofemoral load ratio in biphasics. Interestingly, STB medial-to-lateral bone volume fraction (BV/TV) ratio was also significantly higher (more than double) in biphasics and flexors than in counter-rotators (2.24, 2.00 and 1.00, respectively), whereas in biphasics it was only 10% higher than in flexors and not significantly so. Within the confines of the limited s le size, data suggests that different mechanisms between the biphasic and flexor gait subroups may generate comparable loads upon the tibial plateau and corresponding bony responses, despite significantly lower KAM indices in flexors. Hence, in flexor gait OA patients, conservative treatments designed to reduce KAM, may not be appropriate. Understanding joint loading among walking gait patterns and relationships to bone microarchitecture may aid at identifying/improving management of persons at risk for developing knee OA.
Publisher: Wiley
Date: 28-09-2006
DOI: 10.1111/J.1445-2197.2006.03909.X
Abstract: This article evaluates the risk of interference with the neurovascular structures in the four anterior ankle arthroscopic portals, described on each side of the extensor tendons: anteromedial, medial midline, anterocentral and anterolateral. Complications after ankle arthroscopies have been described in up to 17%, most being neurovascular. To quantify the neurovascular risks we dissected 68 cadaveric feet and evaluated the correlations between tendons, vessels and nerves. The mean distance between tibialis anterior and extensor hallucis longus and between extensor hallucis longus and extensor digitorum longus is 4 mm, but in 10-20% these tendons are in apposition or are overlapped. The tibialis anterior vascular bundle was absent in 11.8%, was located between the tibialis anterior and the extensor hallucis longus in 3% and between the extensor hallucis longus and the extensor digitorum longus in 64.7%. A peroneal vascular bundle or branches of the tibialis anterior vascular bundle were located lateral to the extensor digitorum longus eroneus tertius tendon in 88.2%. Transverse vascular branches were identified in 41.2% over the medial side of the joint line and in 52.9% over the lateral side. The deep peroneal nerve was located between the extensor hallucis longus and the extensor digitorum longus tendons in 58.8%. The superficial peroneal nerve had branches located between the tibialis anterior and the extensor hallucis longus tendons in 2.9%, between the extensor hallucis longus and the extensor digitorum longus tendons in 23.5% and lateral to the extensor digitorum longus eroneus tertius tendon in 32.4%. These results show that the anteromedial and medial midline portals are the safest. The anterolateral portal should be noted not only for the risks to the superficial peroneal nerve, but also to the peroneal vessels.
Publisher: British Editorial Society of Bone & Joint Surgery
Date: 09-2010
DOI: 10.1302/0301-620X.92B9.23893
Abstract: We dissected 20 cadaver hips in order to investigate the anatomy and excursion of the trochanteric muscles in relation to the posterior approach for total hip replacement. String models of each muscle were created and their excursion measured while the femur was moved between its anatomical position and the dislocated position. The position of the hip was determined by computer navigation. In contrast to previous studies which showed a separate insertion of piriformis and obturator internus, our findings indicated that piriformis inserted onto the superior and anterior margins of the greater trochanter through a conjoint tendon with obturator internus, and had connections to gluteus medius posteriorly. Division of these connections allowed lateral mobilisation of gluteus medius with minimal retraction. Analysis of the excursion of these muscles revealed that positioning the thigh for preparation of the femur through this approach elongated piriformis to a maximum of 182%, obturator internus to 185% and obturator externus to 220% of their resting lengths, which are above the thresholds for rupture of these muscles. Our findings suggested that gluteus medius may be protected from overstretching by release of its connection with the conjoint tendon. In addition, failure to detach piriformis or the obturators during a posterior approach for total hip replacement could potentially produce damage to these muscles because of over-stretching, obturator externus being the most vulnerable.
Publisher: Elsevier BV
Date: 05-2020
Publisher: SLACK, Inc.
Date: 03-2019
DOI: 10.3928/01477447-20190118-02
Abstract: The primary aim of this study was to determine whether an electronic, multicenter data collection system could be used to establish normal population reference values for the Hip Disability and Osteoarthritis Outcome Score (HOOS) and the Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC). The secondary aim was to investigate differences in asymptomatic HOOS and WOMAC values reported in 2 geographically distinct English-speaking countries and compare these with a symptomatic arthritic patient cohort. A total of 552 participants were recruited. Asymptomatic Australian and Canadian cohorts were compared combined asymptomatic cohorts were compared with an arthritic cohort. There was a statistically significant association between age and asymptomatic HOOS ( P .0001) and WOMAC ( P .0001) values as age increased, values worsened. Females had worse HOOS and WOMAC values ( P .0001). When compared with age- and sex-matched asymptomatic participants, arthritic participants had worse scores ( P .0001). Asymptomatic Australians had a statistically significant 3.8% better (higher) HOOS ( P .0001) in all age groups ( P .0001). When compared with age- and sex-matched asymptomatic participants, younger arthritic participants reported worse activities of daily living and sports and recreation HOOS values. This observational study established an electronic HOOS and WOMAC patient-reported outcome measures database of asymptomatic in iduals in 2 geographically distinct countries. An asymptomatic control group should be sourced from the same country of origin as the proposed study. Factors that should be considered when recording the HOOS and WOMAC include age, sex, geographic location, history of an inactive hip problem, contralateral hip disease, and active knee, ankle, or foot problems. [ Orthopedics . 2019 42(2):e216–e224.]
Publisher: Jaypee Brothers Medical Publishing
Date: 08-2014
Publisher: Ovid Technologies (Wolters Kluwer Health)
Date: 05-2009
Publisher: Elsevier BV
Date: 06-2012
DOI: 10.1016/J.ARTH.2011.08.023
Abstract: We investigated the effect several lower limb positions have on muscles that are detached to perform hip arthroplasty through posterior and lateral approaches. We used string models and computer navigation to measure the length changes in these muscles throughout hip movements in the anatomical planes and while simulating several sitting and lying postures. Piriformis and the obturators were shortened by sitting and lying postures when the femur was externally rotated and abducted the clinical implication being that such postures have the potential to best protect their repair after a posterior approach. The anterior part of gluteus medius was lengthened with femoral external rotation. This lengthening was prevented, and therefore, theoretically, the gluteus medius repair protected after a lateral approach, by neutral or internal femoral rotation.
Publisher: Georg Thieme Verlag KG
Date: 03-2016
Abstract: Objectives: Hemiarthroplasty induces degenerative changes in the hip joint, which are difficult to evaluate in vivo. Radiostereometric analysis (RSA) is a radiographic measurement technique that has recently been used to measure acetabular cartilage wear in vivo. The aim of the study was to measure acetabular cartilage wear, using this technique, in an ovine model during the first 14 weeks post-implantation. Methods: Measurements of three-dimensional femoral head migration, combined with visual assessments at necropsy and safranin O staining for cartilage integrity, were undertaken. Results: Mean femoral head migration during the first six weeks was 0.525 mm in the medial, 0.144 mm in the cranial, and 0.517 mm in the dorsal direction. The majority of this migration was confirmed to be cartilage wear in the medial and dorsal aspects of the acetabulum at necropsy and with subsequent histological evaluation depicting significant cartilage degeneration. Clinical significance: Radiostereometric analysis is the current gold standard technique for in vivo assessment of implant migration following total hip replacement. This study has utilized RSA to quantify the amount of early cartilage wear in vivo, which was supported by ex vivo evaluations. Accurately measuring the amount of cartilage wear will allow future studies to compare component material and design characteristics prior to clinical use.
Publisher: Wiley
Date: 30-04-2021
DOI: 10.1002/JOR.25051
Abstract: The objectives of this study were to (1) develop a semiautomated method to obtain lesion volume and bone mineral density (BMD) in terms of Hounsfield units from pelvic computed tomography (CT) scans in three regions of interest, and (2) assess accuracy and reliability of the method based on cadaveric CT scans. Image artefacts due to metal implants reduce CT clarity and are more severe with more than one implant in situ. Therefore, accuracy and reliability tests were performed with varying numbers of total hip arthroplasties implanted. To test the accuracy of lesion size measurements, microcomputed tomography was used as a reference. Mean absolute error ranged from 36 to 284 mm 3 after five measurements. Intra‐ and inter‐operator reliability of the entire method was measured for a selection of parameters. All coefficient of variation values were good to excellent for CT scans of the native pelvic anatomy and a CT scans of the same pelvis with one and two implants in situ. Accuracy of quantifying lesion volume decreased with decreasing CT image clarity by 0.6%–3.6% mean absolute relative error. Reliability of lesion volume measurement decreased with decreasing CT clarity. This was also the case for reliability of BMD measurements in the region most disrupted by metal artefact. The presented method proposes an approach for quantifying bone loss which has been proven to be accurate, reliable, and clinically applicable.
Publisher: Wiley
Date: 12-10-2010
DOI: 10.1111/J.1445-2197.2010.05527.X
Abstract: Surviving multi-trauma is strongly associated with emergent resuscitation and treatment in modern medical facilities. Multi-trauma survival before the advent of modern medicine is likely to have been extremely uncommon, particularly in primitive societies. The aim of this study was to investigate the case of an ancient Australian Aboriginal who appeared to have survived multi-trauma. We investigated the skeletal remains of an adult Australian Aboriginal with healed fractures of the right femur and humerus. The time of death was assessed by carbon dating. The sex and approximate age of the subject were assessed from the skeleton's morphometry. The fractured bones were assessed by visual inspection, plain radiographs and computer tomography (CT) scanning. The remains were of a male aged approximately 50 years at the time of his death, approximately 1000 years ago, preceding European settlement. Analysis of the malunions indicated that all fractures occurred in one traumatic event, normally a life-threatening injury combination, and that the subject survived for years after this incident, despite no or failed active treatment of his fractures. The survival of a man living in a primitive society after multi-trauma reflects an impressive depth of nursing and social support in a community of hunter gatherers.
Publisher: Ovid Technologies (Wolters Kluwer Health)
Date: 21-11-2018
Abstract: The acetabular components used in revision total hip arthroplasty (THA) to treat severe acetabular bone defects have high rates of re-revision at mid to long-term follow-up. Early translation of acetabular components used in revision THA is a good predictor of later loosening, and radiostereometric analysis (RSA) is the most sensitive method to measure migration. The objectives of the present study were to use RSA to compare the migration of the porous tantalum acetabular components used to treat severe bone defects with the previously established acceptable proximal translation threshold of ≤1 mm within 2 years, and to determine the effect on migration of the addition of inferior screws through the component into the ischium or pubis. RSA was utilized to measure the migration of 55 porous tantalum components used to treat severe acetabular defects (28 Paprosky IIIA, 27 Paprosky IIIB 21 hips with pelvic discontinuity) at a mean follow-up of 4 years (range, 2 to 12 years). Forty-eight of the 55 components migrated less than the threshold that predicts later loosening ( mm) and 50 had not been re-revised at the time of the latest follow-up. Seven components, none of which had inferior screw fixation, exceeded the translation threshold. Of these, 6 were implanted to treat pelvic discontinuity. Of those 6 components, 5 were re-revised for loosening related to patient symptoms. At 2 years, the absolute median proximal translation of components with inferior screw fixation was |0.3| mm (range, |0.1| to |0.9| mm), compared with |0.4| mm (range, |0.03| to |16.4| mm) for those without inferior screws (p = 0.04). As measured with use of RSA, the majority of porous tantalum acetabular components used in a revision THA to treat severe acetabular defects had acceptable early migration. This predicts good long-term survivorship of these components. The use of inferior screws further improved acetabular component fixation. Therapeutic Level III . See Instructions for Authors for a complete description of levels of evidence.
Publisher: Cold Spring Harbor Laboratory
Date: 10-07-2021
DOI: 10.1101/2021.07.08.21257202
Abstract: Autosomal Dominant Osteopetrosis type II (ADOII), also known as Albers-Schönberg disease, is caused by mutation of the CLCN7 chloride channel gene and is characterized by reduced bone resorption. Here we report on an in idual with the classic features of ADOII, who had a history of fractures from childhood, displayed high bone mass and characteristic “sandwich vertebrae” on x-ray. Our genetic analyses showed no amino acid converting mutation in the patient’s DNA but we did find evidence of haploinsufficiency of CLCN7 mRNA. An iliac crest bone s le from the patient revealed bone tissue and material abnormalities relative to normal controls based on quantitative backscattered electron imaging and histomorphometric analyses. Additionally to lamellar bone, we observed significant amounts of woven bone and mineralised cartilage, as well as an increased frequency and thickness (up to 15 microns) of cement lines. Giant osteoclasts with numerous nuclei were present. The bone mineralisation density distribution (BMDD) of the entire bone area revealed markedly increased average mineral content of the dense bone (CaMean T-score +10.1) and frequency of bone with highest mineral content (CaHigh T-score +19.6), suggesting continued mineral accumulation and lack of bone remodelling. Osteocyte lacunae sections (OLS) characteristics were unremarkable except the OLS shape which was unusually circular. Together, our findings suggest that the reduced expression of CLCN7 mRNA in osteoclasts, and possibly also osteocytes, causes poorly remodelled bone with abnormal bone matrix with high mineral content. This together with the lack of adequate bone repair mechanisms makes the material brittle and prone to fracture.
Publisher: Ovid Technologies (Wolters Kluwer Health)
Date: 12-2015
Publisher: Cold Spring Harbor Laboratory
Date: 18-04-2022
DOI: 10.1101/2022.04.17.488608
Abstract: Polyethylene (PE) liners are a common bearing surface of orthopaedic prostheses. Wear particles of ultra-high molecular weight PE (UHMWPE) contribute to periprosthetic osteolysis, a major cause of aseptic loosening. Vitamin E is added to some PE liners to prevent oxidative degradation. Osteocytes, an important cell type for controlling both bone mineralisation and bone resorption, have been shown to respond UHMWPE particles by upregulating pro-osteoclastogenic and osteocytic osteolysis. Here, we examined the effects of the vitamin E analogues α-tocopherol and γ-tocotrienol alone or in the context of UHMWPE particles on human osteocyte gene expression and mineralisation behaviour. Human osteoblasts differentiated to an osteocyte-like stage were exposed to UHMWPE wear particles in the presence or absence of either α-Tocopherol or γ-Tocotrienol. Both α-Tocopherol and γ-Tocotrienol induced antioxidant-related gene expression. UHMWPE particles independently upregulated antioxidant gene expression, suggesting an effect of wear particles on oxidative stress. Both vitamin E analogues strongly induced OPG mRNA expression and γ-Tocotrienol also inhibited RANKL mRNA expression, resulting in a significantly reduced RANKL : OPG mRNA ratio (p 0.01) overall. UHMWPE particles reversed the suppressive effect of α-Tocopherol but not of γ-Tocotrienol on this pro-osteoclastogenic index. UHMWPE particles also upregulated osteocytic-osteolysis related gene expression. Vitamin E analogues alone or in combination with UHMWPE particles also resulted in upregulation of these genes. Consistent with this, both vitamin E analogues promoted calcium release from mineralised cultures of osteocyte-like cells. Our findings suggest that while vitamin E may suppress osteocyte support of osteoclastogenesis in the presence of UHMWPE particles, the antioxidant effect may induce osteocytic osteolysis, which could promote periprosthetic osteolysis. It will be important to conduct further studies of vitamin E to determine the long-term effects of its inclusion in prosthetic materials.
Publisher: MDPI AG
Date: 18-10-2018
DOI: 10.3390/MET8100840
Abstract: Metallic taper junctions of modular total hip replacement implants are analysed for corrosion damage using visual scoring based on different granularity levels that span from analysing the taper holistically to iding the taper into several distinct zones. This study aims to objectively explore the spatial distribution and the severity of corrosion damage onto the surface of metallic stem tapers. An ordinal logistic regression model was developed to find the odds of receiving a higher score at eight distinct zones of 137 retrieved stem tapers. A method to find the order of damage severity across the eight zones is introduced based on an overall test of statistical significance. The findings show that corrosion at the stem tapers occurred more commonly in the distal region in comparison with the proximal region. Also, the medial distal zone was found to possess the most severe corrosion damage among all the studied eight zones.
Publisher: Ovid Technologies (Wolters Kluwer Health)
Date: 08-2010
Publisher: Ovid Technologies (Wolters Kluwer Health)
Date: 12-2010
Publisher: Springer Science and Business Media LLC
Date: 15-07-2010
Publisher: Hindawi Limited
Date: 2015
DOI: 10.1155/2015/758123
Abstract: Modularity at the head-neck junction of the femoral component in THA became popular as a design feature with advantages of decreasing implant inventory and allowing adjustment of leg length, offset, and soft tissue balancing through different head options. The introduction of a new modular interface to femoral stems that were previously monoblock, or nonmodular, comes with the potential for corrosion at the taper junction through mechanically assisted crevice corrosion. The incidence of revision hip arthroplasty is on the rise and along with improved wear properties of polyethylene and ceramic, use of larger femoral head sizes is becoming increasingly popular. Taper corrosion appears to be related to all of its geometric parameters, material combinations, and femoral head size. This review article discusses the pathogenesis, risk factors, clinical assessment, and management of taper corrosion at the head-neck junction.
Publisher: MDPI AG
Date: 21-08-2023
DOI: 10.3390/PROSTHESIS5030055
Abstract: Fretting corrosion is a known failure mechanism of total hip replacement (THR) that can lead to revision surgery. Implant retrieval studies have thoroughly documented the occurrence of fretting corrosion in THR implants and its correlation with implant- and patient-related factors. Although implant retrieval studies benefit both clinicians and implant manufacturers, the limitations of these types of studies need to be acknowledged. For ex le, while some factors are routinely investigated for a possible correlation with failure due to fretting corrosion, other factors are often assumed to have no effect. To improve on these limitations, this review investigates the most significant patient- and implant-related risk factors for fretting corrosion of THR implants for both published retrieval studies and joint replacement registries. The findings and limitations are discussed critically. It is concluded that retrieval studies add significant insight into implant failure mechanisms and should be used in conjunction with joint replacement registry reports. It is suggested that the development of reliable predictive models based on implant failure risk factors and decision-making support systems could lead to enhanced implant longevity.
Publisher: Elsevier BV
Date: 06-2014
DOI: 10.1016/J.INJURY.2014.04.006
Abstract: The progress of fracture healing is directly related to an increasing stiffness and strength of the healing fracture. Similarly the weight bearing capacity of a bone directly relates to the mechanical stability of the fracture. Therefore, assessing the progress of fracture repair can be based on the measurement of the mechanical stability of the healing fracture. However, fracture stability is difficult to assess directly due to various obstacles of which shielding of the mechanical properties by the fracture fixation construct is the most relevant one. Several assessment methods have been proposed to overcome these obstacles and to obtain some sort of mechanical surrogate describing the stability of the fracture. The most direct method is the measurement of the flexibility of a fracture under a given external load, which comprises the challenge of accurately measuring the deformation of the bone. Alternative approaches include the measurement of load share between implant and bone by internal or by external sensors. A direct 3 dimensional measurement of bone displacement is provided by radiostereometric analysis which can assess fracture migration and can detect fracture movement under load. More indirect mechanical methods induce cyclic perturbations within the bone and measure the response as a function of healing time. At lower frequencies the perturbations are induced in the form of vibration and at higher frequencies in the form of ultrasonic waves. Both methods provide surrogates for the mechanical properties at the fracture site. Although biomechanical properties of a healing fracture provide a direct and clinically relevant measure for fracture healing, their application will in the near future be limited to clinical studies or research settings.
Publisher: Elsevier BV
Date: 07-2018
DOI: 10.1016/J.JOCA.2018.02.897
Abstract: To determine the change in walking gait biomechanics after total hip arthroplasty (THA) for osteoarthritis (OA) compared to the pre-operative gait status, and to compare the recovery of gait following THA with healthy in iduals. Systematic review with meta-analysis of studies investigating changes in gait biomechanics after THA compared to (1) preoperative levels and (2) healthy in iduals. Data were pooled at commonly reported time points and standardised mean differences (SMDs) were calculated in meta-analyses for spatiotemporal, kinematic and kinetic parameters. Seventy-four studies with a total of 2,477 patients were included. At 6 weeks postoperative, increases were evident for walking speed (SMD: 0.32, 95% confidence intervals (CI) 0.14, 0.50), stride length (SMD: 0.40, 95% CI 0.19, 0.61), step length (SMD: 0.41, 95% CI 0.23, 0.59), and transverse plane hip range of motion (ROM) (SMD: 0.36, 95% CI 0.05, 0.67) compared to pre-operative gait. Sagittal, coronal and transverse hip ROM was significantly increased at 3 months (SMDs: 0.50 to 1.07). At 12 months postoperative, patients demonstrated deficits compared with healthy in iduals for walking speed (SMD: -0.59, 95% CI -1.08 to -0.11), stride length (SMD: -1.27, 95% CI -1.63, -0.91), single limb support time (SMD: -0.82, 95% CI -1.23, -0.41) and sagittal plane hip ROM (SMD: -1.16, 95% CI -1.83, -0.49). Risk of bias scores ranged from seven to 24 out of 26. Following THA for OA, early improvements were demonstrated for spatiotemporal and kinematic gait patterns compared to the pre-operative levels. Deficits were still observed in THA patients compared to healthy in iduals at 12 months.
Publisher: Wiley
Date: 07-05-2015
DOI: 10.1002/JOR.22905
Abstract: Tibial plateau fractures are common, but little evidence exists for their postoperative management, especially when recommending if patients should weight bear at all, partially, or as tolerated. In this study, we describe the loads passing through the fracture construct and the associated fracture migration over the first year following surgery. Nine patients were treated with open reduction and internal fixation and instructed to weight bear as tolerated. Fracture loading and migration were assessed at 2, 12, 26, and 52 weeks postoperative. Fracture loading was calculated as the knee joint reaction force (peak, average, the angle of the force vector, and the point of force application) using gait analysis and an inverse dynamics musculoskeletal model. Fracture migration was assessed using radiostereometric analysis. The fractures were progressively loaded during the rehabilitation phase. The point of application of the load shifted from neutral to medial by week 26 for all patients. Migration during the first postoperative year was within current clinical acceptable limits. The peak load during walking at each time point was not associated with fracture fragment migration and does not appear to exceed the elastic limit of the fracture construct.
Publisher: Ovid Technologies (Wolters Kluwer Health)
Date: 07-2009
Publisher: British Editorial Society of Bone & Joint Surgery
Date: 09-2014
DOI: 10.1302/0301-620X.96B9.34269
Abstract: Peri-acetabular osteotomy is an established surgical treatment for symptomatic acetabular dysplasia in young adults. An anteroposterior radiograph of the pelvis is commonly used to assess the extent of dysplasia as well as to assess post-operative correction. Radiological prognostic factors include the lateral centre-edge angle, acetabular index, extrusion index and the acetabular version. Standing causes a change in the pelvis tilt which can alter certain radiological measurements relative to the supine position. This article discusses the radiological indices used to assess dysplasia and reviews the effects of patient positioning on these indices with a focus on assessment for a peri-acetabular osteotomy. Intra-operatively, fluoroscopy is commonly used and the implications of using fluoroscopy as a modality to assess the various radiological indices along with the effects of using an anteroposterior or posteroanterior fluoroscopic view are examined. Each of these techniques gives rise to a slightly different image of the pelvis as the final image is sensitive to the position of the pelvis and the projection of the x-ray beam. Cite this article: Bone Joint J 2014 -B:1155–60.
Publisher: Ovid Technologies (Wolters Kluwer Health)
Date: 11-2012
Publisher: Wiley
Date: 07-04-2019
DOI: 10.1002/JOR.24232
Abstract: Metaphyseal augments, such as sleeves, have been introduced to augment the fixation of revision total knee replacement (rTKR) components, and can be used with or without a stem. The effect of sleeve size in combination with stems on the primary stability and load transfer of a rTKR implant in AORI type IIB defects where the defect involves both condyles are poorly understood. The aim of this study was to examine the primary stability of revision tibial tray augmented with a sleeve in an AORI type IIB defect which involves both condyles with loss of cortical and cancellous bone. Finite element models were generated from computed tomography (CT) scans of nine in iduals. All the bones used in the study had an AORI type IIB defect. The cohort included eight females (mean weight: 64 kg, height: 1.6 m). Material properties were s led from CT data and assigned to the FE model. Joint contact forces for level gait, stair descent, and squat were applied. Stemless sleeved implants under various loading conditions were shown to have adequate primary stability in all AORI type IIB defects investigated. Adding a stem only marginally improved the primary stability of the implant but reduced the strain in the metaphysis compared to stemless implants. Once good initial mechanical stability was established with a sleeve, there was no benefit, in terms of primary stability or bone strains, from increasing sleeve size. This study suggests that metaphyseal sleeves, without a stem, can provide the required primary stability required by a rTKR tibial implant, to reconstruct an AORI type IIB defect. © 2019 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res.
Publisher: Elsevier BV
Date: 10-2017
DOI: 10.1016/J.MSEC.2017.05.086
Abstract: A detailed investigation was performed to characterize the fretting wear and corrosion damage to the neck component of a CoCrMo stem from a metal-on-polyethylene implant retrieved after 99months. The stem was a low-carbon (0.07wt%) wrought Co-28Cr-6Mo alloy with no secondary carbide phases in the matrix (γ-phase). The original design of the neck surface contained an intentionally fabricated knurled profile with a valley-to-peak range of approximately 11μm. Roughness measurements indicated that the tip of the knurled profile was significantly damaged, especially in the distal medial region of the neck, with up to a 22% reduction in the mean peak-to-valley height (R
Publisher: Wiley
Date: 25-11-2020
DOI: 10.1002/JOR.24914
Abstract: This preliminary study quantified tibia cartilage thickness (Cart.Th), subchondral bone plate thickness (SBPl.Th) and subchondral trabecular bone (STB) microarchitecture in subjects with varus‐ or valgus‐ malaligned knees diagnosed with end‐stage knee osteoarthritis (OA) and compared them to controls (non‐OA). Tibial plateaus from 25 subjects with knee‐OA (undergoing knee arthroplasty) and 15 cadavers (controls) were micro‐CT scanned (17 µm/voxel). Joint alignment was classified radiographically for OA subjects (varus‐aligned n = 18, valgus‐aligned n = 7). Cart.Th, SBPl.Th, STB bone volume fraction (BV/TV) and their medial‐to‐lateral ratios were analyzed in anteromedial, anterolateral, posteromedial and posterolateral subregions. Varus‐OA and valgus‐OA were compared to controls. Compared to controls (1.19–1.54 mm), Cart.Th in varus‐OA was significantly lower anteromedially (0.58 mm, −59%) and higher laterally (2.19–2.47 mm, +60–63%) in valgus‐OA, Cart.Th was significantly higher posteromedially (1.86 mm, +56%). Control medial‐to‐lateral Cart.Th ratios were around unity (0.8–1.1), in varus‐OA significantly below (0.2–0.6) and in valgus‐OA slightly above (1.0–1.3) controls. SBPl.Th and BV/TV were significantly higher medially in varus‐OA (0.58‐0.72 mm and 37–44%, respectively) and laterally in valgus‐OA (0.60–0.61 mm and 32–37%), compared to controls (0.26–0.47 mm and 18–37%). In varus‐OA, the medial‐to‐lateral SBPl.Th and BV/TV ratios were above unity (1.4–2.4) and controls (0.8–2.1) in valgus‐OA they were closer to unity (0.8‐1.1) and below controls. Varus‐ and valgus‐OA tibia differ significantly from controls in Cart.Th, SBPl.Th and STB microarchitecture depending on joint alignment, suggesting structural changes in OA may reflect differences in medial‐to‐lateral load distribution upon the tibial plateau. Here we identified an inverse relationship between cartilage thickness and underlying subchondral bone, suggesting a whole‐joint response in OA to daily stimuli.
Publisher: Springer Science and Business Media LLC
Date: 04-01-2021
Publisher: Ovid Technologies (Wolters Kluwer Health)
Date: 2019
Abstract: We describe 2 cases of nonagenarians with periprosthetic knee fractures that were not amenable to either standard internal fixation nor prosthesis revision because of infected leg ulcers in the same limb. The fractures were internally fixed by percutaneous insertion of medial and lateral plates that spanned the knee. Both patients returned to their baseline level of activity without developing surgical site infections. Percutaneous bridging plates that span the knee are a useful option for treating these difficult cases.
Publisher: MDPI AG
Date: 12-05-2020
DOI: 10.3390/JCM9051437
Abstract: Introduction: Ligament injuries around the knee joint and knee dislocations are rare but potentially complex injuries associated with high-energy trauma. Concomitant neurovascular injuries further affect their long-term clinical outcomes. In contrast to isolated ligamentous knee injuries, epidemiologic data and knowledge on predicting knee injuries in severely injured patients is still limited. Methods: The TraumaRegister DGU® (TR-DGU) was queried (01/2009–12/2016). Inclusion criteria for selection from the database: maximum abbreviated injury severity ≥ 3 points (MAIS 3+). Participating countries: Germany, Austria, and Switzerland. The two main groups included a “control” and a “knee injury” group. The injury severity score (ISS) and new ISS (NISS) were used for injury severity classification, and the abbreviated injury scale (AIS) was used to classify the severity of the knee injury. Logistic regression analysis was performed to evaluate various risk factors for knee injuries. Results: The study cohort included 139,462 severely injured trauma patients. We identified 4411 in iduals (3.2%) with a ligament injury around the knee joint (“knee injury” group) and 1153 patients with a knee dislocation (0.8%). The risk for associated injuries of the peroneal nerve and popliteal artery were significantly increased in dislocated knees when compared to controls (peroneal nerve from 0.4% to 6.7%, popliteal artery from 0.3% to 6.9%, respectively). Among the predictors for knee injuries were specific mechanisms of injury: e.g., pedestrian struck (Odds ratio [OR] 3.2, 95% confidence interval [CI]: 2.69–3.74 p ≤ 0.001), motorcycle (OR 3.0, 95% CI: 2.58–3.48, p ≤ 0.001), and motor vehicle accidents (OR 2.2, 95% CI: 1.86–2.51, p ≤ 0.001) and associated skeletal injuries, e.g., patella (OR 2.3, 95% CI: 1.99–2.62, p ≤ 0.001), tibia (OR 1.9, 95% CI: 1.75–2.05, p ≤ 0.001), and femur (OR 1.8, 95% CI: 1.64–1.89, p ≤ 0.001), but neither male sex nor general injury severity (ISS). Conclusion: Ligament injuries and knee dislocations are associated with high-risk mechanisms and concomitant skeletal injuries of the lower extremity, but are not predicted by general injury severity or sex. Despite comparable ISS, knee injuries prolong the hospital length of stay. Delayed or missed diagnosis of knee injuries can be prevented by comprehensive clinical evaluation after fracture fixation and a high index of suspicion is advised, especially in the presence of the above mentioned risk factors.
Publisher: Cold Spring Harbor Laboratory
Date: 25-04-2023
DOI: 10.1101/2023.04.23.537998
Abstract: 1. Few human osteocyte in vitro models exist and the differentiation of immature osteoblasts to an osteocyte stage typically takes at least 4-weeks of culture, making the study of this process challenging and time consuming. The osteosarcoma cell line Saos-2 has proved to be a useful model of human osteoblast differentiation through to a mature osteocyte-like stage. Culture under osteogenic conditions in a standard 5% CO 2 and normoxic (21% O 2 ) atmosphere results in reproducible mineralisation and acquisition of mature osteocyte markers over the expected 28-35 day culture period. In order to expedite experimental assays, we tested whether reducing available oxygen to mimic concentrations experienced by osteocytes in vivo would increase the rate of differentiation of Saos-2 cells. Cells cultured in a 5% CO 2 , 1% O 2 atmosphere exhibited accelerated deposition of mineral, reaching near saturation by 14 days as demonstrated with the Alizarin Red and Von Kossa staining. The gene expression of the major hypoxia-induced transcription factor HIF1α and the key osteogenic transcription factor RUNX2 were both elevated under 1% O 2 . Early ( COLA1, MEPE ) and mature ( PHEX, DMP1 and SOST ) osteocyte markers were also upregulated earlier under hypoxic compared to normoxic growth conditions. Thus, culture under low oxygen accelerates key markers of osteocyte differentiation, resulting in a useful human osteocyte-like in vitro cell model within 14 days.
Publisher: Elsevier BV
Date: 03-2016
DOI: 10.1016/J.ACTBIO.2016.01.016
Abstract: Periprosthetic osteolysis (PO) leading to aseptic loosening, is the most common cause of failure of total hip replacement (THR) in the mid- to long-term. Polyethylene (PE) particulates from the wear of prosthesis liners are bioactive and are implicated in the initiation and or progression of osteolysis. Evidence exists that cells of the osteoblast/osteocyte lineage are affected by PE particles and contribute to the catabolic response by promoting osteoclastic bone resorption. In this study, we hypothesised that osteocytes contribute directly to PO by removing bone from their perilacunar matrix. Osteocyte responses to ultra-high molecular weight PE (UHMWPE) particles were examined in vitro in human primary osteocyte-like cultures, in vivo in the mouse calvarial osteolysis model, and in the acetabulum of patients undergoing revision total hip replacement (THR) surgery for PO. Osteocytes exposed to UHMWPE particles showed upregulated expression of catabolic markers, MMP-13, carbonic anhydrase 2 (CA2), cathepsin K (CTSK) and tartrate resistant acid phosphatase (TRAP), with no effect on cell viability, as assessed by Caspase 3 activity. Consistent with this catabolic activity causing perilacunar bone loss, histological analysis of calvarial sections from mice exposed to UHMWPE revealed a significant (p<0.001) increase in osteocyte lacunar area (Lac.Ar) compared to sham-operated animals. Furthermore, acetabular biopsies from patients with PO also showed significantly (p<0.001) increased osteocyte lacunar size in trabecular bone adjacent to PE particles, compared with osteocyte lacunar size in bone from primary THR patients. Together, these findings suggest a previously unrecognised action of UHMWPE wear particles on osteocytes, which directly results in a loss of osteocyte perilacunar bone. This action may exacerbate the indirect pro-osteoclastic action of UHMWPE-affected osteocytes, previously shown to contribute to aseptic loosening of orthopaedic implants. This study addresses the clinical problem of periprosthetic osteolysis, bone loss in response to polyethylene wear particles derived from materials used in orthopaedic implants. Periprosthetic osteolysis has been thought to be due largely to wear particles stimulating the activity of bone resorbing osteoclasts. However, in this study we demonstrate for the first time that polyethylene particles stimulate another type of bone loss, mediated by the direct activity of bone mineral embedded osteocytes, termed osteocytic osteolysis or osteocyte perilacunar remodelling. This study provides new mechanistic insight into wear-particle mediated bone loss and represents a new paradigm for the way in which bone cells, namely osteocytes, the key controlling cell type in bone, react to biomaterials.
Publisher: Springer Science and Business Media LLC
Date: 26-02-2019
Publisher: British Editorial Society of Bone & Joint Surgery
Date: 04-2019
DOI: 10.1302/0301-620X.101B4.BJJ-2018-1240.R1
Abstract: The purpose of this exploratory study was to investigate if the 24-hour activity profile (i.e. waking activities and sleep) objectively measured using wrist-worn accelerometry of patients scheduled for total hip arthroplasty (THA) improves postoperatively. A total of 51 THA patients with a mean age of 64 years (24 to 87) were recruited from a single public hospital. All patients underwent THA using the same surgical approach with the same prosthesis type. The 24-hour activity profiles were captured using wrist-worn accelerometers preoperatively and at 2, 6, 12, and 26 weeks postoperatively. Patient-reported outcomes (Hip Disability and Osteoarthritis Outcome Score (HOOS)) were collected at all timepoints except two weeks postoperatively. Accelerometry data were used to quantify the intensity (sedentary, light, moderate, and vigorous activities) and frequency (bouts) of activity during the day and sleep efficiency. The analysis investigated changes with time and differences between Charnley class. Patients slept or were sedentary for a mean of 19.5 hours/day preoperatively and the 24-hour activity pattern did not improve significantly postoperatively. Outside of sleep, the patients spent their time in sedentary activities for a mean of 620 minutes/day (sd 143) preoperatively and 641 minutes/day (sd 133) six months postoperatively. No significant improvements were observed for light, moderate, and vigorous intensity activities (p = 0.140, p = 0.531, and p = 0.407, respectively). Sleep efficiency was poor ( 85%) at all timepoints. There was no postoperative improvement in sleep efficiency when adjusted for medications (p 0.05). Patient-reported outcome measures showed a significant improvement with time in all domains when compared with preoperative levels. There were no differences with Charnley class at six months postoperatively. However, Charnley class C patients were more sedentary at two weeks postoperatively when compared with Charnley class A patients (p 0.05). There were no further differences between Charnley classifications. This study describes the 24-hour activity profile of THA patients for the first time. Prior to THA, patients in this cohort were inactive and slept poorly. This cohort shows no improvement in 24-hour activity profiles at six months postoperative. Cite this article: Bone Joint J 2019 -B:415–425.
Publisher: Wiley
Date: 13-02-2018
DOI: 10.1002/JOR.23851
Abstract: Traditionally, diaphyseal stems have been utilized to augment the stability of revision total knee replacement (rTKR) implants. More recently metaphyseal augments, such as sleeves, have been introduced to further augment component fixation. The effect of augments such as stems and sleeves have on the primary stability of a rTKR implant is poorly understood, however it has important implications on the complexity, costs and survivorship of the procedure. Finite element analysis was used to investigate the primary stability and strain distribution of various size stems and sleeves used in conjunction with a cementless revision tibial tray. The model was built from computer tomography images of a single healthy tibia obtained from an 81-year-old patient to which an Anderson Orthopaedic Research Institute (AORI) IIA defect was virtually added. The influences of varying body mass index (BMI) and bone modulus were also investigated. Stemless sleeves were found to provided adequate primary implant stability (average implant micro-motion <50 μm) for the studied defect. Addition of a stem did not enhance the primary stability. Furthermore, this study found that varying BMI and bone modulus had a considerable effect on strain distribution but negligible effect on micro-motion in the sleeve area. In conclusion, the addition of diaphyseal stem to a metaphyseal sleeve had little benefit in enhancing the primary stability of tibial trays augmented when simulating reconstructions of AORI IIA tibial defects. Additional studies are required to determine the relative benefit of the diaphyseal stem when using metaphyseal sleeves defects with more extensive bone loss. © 2018 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 36:1876-1886, 2018.
Publisher: Elsevier BV
Date: 11-2018
DOI: 10.1016/J.MEDENGPHY.2018.08.002
Abstract: Visual scoring of damage at taper junctions is the sole method to quantify corrosion in large-scale retrieval studies of failed hip replacement implants. This study introduces an intelligent image analysis-based method that objectively rates corrosion at stem taper of retrieved hip implants according to the well-known Goldberg scoring method. A Support Vector Machine classifier was used that takes in vectors of global and local textural features and assigns scores to the corresponding images. Bayesian optimisation fine-tunes the hyperparameters of the classifier to minimise the cross-validation error.
Publisher: Elsevier BV
Date: 09-2015
DOI: 10.1016/J.MCE.2015.06.021
Abstract: Sclerostin, the SOST gene product, is a negative regulator of bone formation and a positive regulator of bone resorption. In this study, treatment of human primary osteoblasts, including cells differentiated to an osteocyte-like stage, with 1α,25-dihydroxyvitaminD3 (1,25D) resulted in the dose-dependent increased expression of SOST mRNA. A similar effect was observed in human trabecular bone s les cultured ex vivo, and in osteocyte-like cultures of differentiated SAOS2 cells. Treatment of SAOS2 cells with 1,25D resulted in the production and secretion of sclerostin protein. In silico analysis of the human SOST gene revealed a single putative DR3-type vitamin D response element (VDRE) at position -6216 bp upstream of the transcription start site (TSS). This sequence was confirmed to have strong VDRE activity by luciferase reporter assays and electrophoretic mobility shift analysis (EMSA). Sequence substitution in the VDR/RXR half-sites abolished VDRE reporter activity and binding of nuclear proteins. A 6.3 kb fragment of the human proximal SOST promoter demonstrated responsiveness to 1,25D. The addition of the evolutionary conserved region 5 (ECR5), a known bone specific enhancer region, ahead of the 6.3 kb fragment increased basal promoter activity but did not increase 1,25D responsiveness. Site-specific mutagenesis abolished the responsiveness of the 6.3 kb promoter to 1,25D. We conclude that 1,25D is a direct regulator of human SOST gene and sclerostin protein expression, extending the pathways of control of sclerostin expression. At least some of this responsiveness is mediated by the identified classical VDRE however the nature of the transcriptional regulation by 1,25D warrants further investigation.
Publisher: SAGE Publications
Date: 16-05-2016
Abstract: The posterior approach to the hip is the most common extensile approach used, however exposure is limited superiorly by the superior gluteal neurovascular bundle (SGNB). The extra-pelvic course of the SGNB demonstrates variability between in iduals, occasionally located only 1 cm from the acetabular rim. In complex acetabular reconstructions where the application of a reinforcement cage maybe required protecting the SGNB is challenging. The flanges of these cages are designed to sit on the ilium superior to the acetabular rim and to receive screws for fixation. The application of such cages may result in iatrogenic injury to the SGNB by way of forceful retraction or entrapment. We describe a technique that involves exposure and release of the SGNB such that the flanges of cage constructs may be safely applied.
Publisher: Elsevier BV
Date: 06-2015
DOI: 10.1016/J.INJURY.2015.02.019
Abstract: Osteoporotic tibial plateau fractures (TPFs) are difficult to treat with either open reduction internal fixation (ORIF) or acute total knee arthroplasty (TKA). They have high complication rates, poor outcomes and often fail in the short- to mid-term. We investigated the use of impaction bone grafting (IBG) as an adjunct to stabilise the fracture in a cohort of osteoporotic TPFs. Nine consecutive osteoporotic TPFs were surgically stabilised with ORIF augmented with IBG or with IBG alone (one pure depression fracture) using on average allograft from 2 femoral heads/case (range 1-4 heads or 25-100 cm(3)). The median bone mineral density T-score of the patients was -2.9 (-2.5 to -4.5). All patients were mobilised weight-bearing as tolerated immediately after surgery and had regular follow-up to a minimum of 2 years where functional scores were taken and gait was assessed. Fracture reduction was assessed on plain radiographs and computed tomography (CT) scans maintenance of fracture reduction was monitored using plain radiographs, CT and radiostereometric analysis (RSA). Bone graft remodelling was assessed by comparison of immediate post-operative CT scans with scans at a minimum of 1 year. All surgeries were uneventful. All patients progressed to full weight bearing within 6 weeks of surgery and regained a normal gait by 3 months. Seven fractures healed with a cranio-caudal migration of less than 3mm (range 0-2.6mm using RSA and 0-2mm using CT). Two fractures had an isolated posterolateral fragment depression of 13.5mm and 9 mm, respectively, which did not affect the overall joint alignment or clinical outcomes at short-term follow-up. At latest CT follow-up, on average 51% of the graft area (range 36-70%) had remodelled into new host bone. Impaction bone grafting shows promising results as an adjunct to the surgical stabilisation of osteoporotic TPFs. In this case series the technique provided enough fracture stability for patients to mobilise weight-bearing as tolerated immediately after surgery and achieve full weight-bearing by the sixth postoperative week. There was no failure of fixation and 7 of the 9 cases healed with minimal fracture displacement.
Publisher: Ovid Technologies (Wolters Kluwer Health)
Date: 27-05-2021
Abstract: This article was updated on July 19, 2021, because of a previous error. On page 1172, in the Results section entitled “Sedentary Activity,” the sentence that had read “Postoperatively, 32% at 1 year and 14% at 2 years were sedentary for hours per day.” now reads “Postoperatively, 32% at 1 year and 41% at 2 years were sedentary for hours per day.” Despite marked improvements in self-reported pain, perceived functional ability, and gait function following primary total hip arthroplasty (THA), it remains unclear whether these improvements translate into improved physical activity and sleep behaviors. The aim of this study was to determine the change in 24-hour activity profile (waking activities and sleep) and laboratory-based gait function from preoperatively to 2 years following the THA. Fifty-one patients undergoing primary THA at a single public hospital were recruited. All THAs were performed using a posterior surgical approach with the same prosthesis type. A wrist-worn accelerometer was used to capture 24-hour activity profiles preoperatively and at 1 and 2 years postoperatively. Three-dimensional gait analysis was performed to determine changes in temporospatial and kinematic parameters of the hip and pelvis. Patients showed improvements in all temporospatial and kinematic parameters with time. Preoperatively, patients were sedentary or asleep for a mean time (and standard deviation) of 19.5 ± 2.2 hours per day. This remained unchanged up to 2 years postoperatively (19.6 ± 1.3 hours per day). Sleep efficiency remained suboptimal ( %) at all time points and was worse at 2 years (77% ± 10%) compared with preoperatively (84% ± 5%). More than one-quarter of the s le were sedentary for hours per day at 1 year (32%) and 2 years (41%), which was greater than the preoperative percentage (21%). Patients accumulated their activity performing light activities however, patients performed less light activity at 2 years compared with preoperative levels. No significant differences (p = 0.935) were observed for moderate or vigorous activity across time. Together with improvements in self-reported pain and perceived physical function, patients had significantly improved gait function postoperatively. However, despite the opportunity for patients to be more physically active postoperatively, patients were more sedentary, slept worse, and performed less physical activity at 2 years compared with preoperative levels. Therapeutic Level IV . See Instructions for Authors for a complete description of levels of evidence.
Publisher: British Editorial Society of Bone & Joint Surgery
Date: 06-2011
DOI: 10.1302/0301-620X.93B6.26122
Abstract: We investigated the stability of seven Schatzker type II fractures of the lateral tibial plateau treated by subchondral screws and a buttress plate followed by immediate partial weight-bearing. In order to assess the stability of the fracture, weight-bearing inducible displacements of the fracture fragments and their migration over a one-year period were measured by differentially loaded radiostereometric analysis and standard radiostereometric analysis, respectively. The mean inducible craniocaudal fracture fragment displacements measured −0.30 mm (−0.73 to 0.02) at two weeks and 0.00 mm (−0.12 to 0.15) at 52 weeks. All inducible displacements were elastic in nature under all loads at each examination during follow-up. At one year, the mean craniocaudal migration of the fracture fragments was −0.34 mm (−1.64 to 1.51). Using radiostereometric methods, this case series has shown that in the Schatzker type II fractures investigated, internal fixation with subchondral screws and a buttress plate provided adequate stability to allow immediate post-operative partial weight-bearing, without harmful consequences.
Publisher: Ovid Technologies (Wolters Kluwer Health)
Date: 02-2015
Publisher: British Editorial Society of Bone & Joint Surgery
Date: 08-2015
DOI: 10.1302/0301-620X.97B8.34632
Abstract: The outcome of 219 revision total hip arthroplasties (THAs) in 98 male and 121 female patients, using 137 long length and 82 standard length cemented collarless double-taper femoral stems in 211 patients, with a mean age of 72 years (30 to 90) and mean follow-up of six years (two to 18) have been described previously. We have extended the follow-up to a mean of 13 years (8 to 20) in this cohort of patients in which the pre-operative bone deficiency Paprosky grading was IIIA or worse in 79% and 73% of femurs with long and standard stems, respectively. For the long stem revision group, survival to re-revision for aseptic loosening at 14 years was 97% (95% confidence interval (CI) 91 to 100) and in patients aged 70 years, survival was 100%. Two patients (two revisions) were lost to follow-up and 86 patients with 88 revisions had died. Worst-case analysis for survival to re-revision for aseptic loosening at 14 years was 95% (95% CI 89 to 100) and 99% (95% CI 96 to 100) for patients aged 70 years. One additional long stem was classified as loose radiographically but not revised. For the standard stem revision group, survival to re-revision for aseptic loosening at 14 years was 91% (95% CI 83 to 99). No patients were lost to follow-up and 49 patients with 51 hips had died. No additional stems were classified as loose radiographically. Femoral revision using a cemented collarless double-taper stem, particularly with a long length stem, and in patients aged 70 years, continues to yield excellent results up to 20 years post-operatively, including in hips with considerable femoral metaphyseal bone loss. Cite this article: Bone Joint J 2015 -B:1038–45.
Publisher: Elsevier BV
Date: 07-2017
DOI: 10.1016/J.INJURY.2017.04.056
Abstract: Fixation strength of constructs placed across the pubic symphysis after injury is dependent on screw length, maximisation of which requires knowledge of the bony anatomy. The aim of this study was to describe the ideal angle of drilling to achieve maximal safe screw placement within the pubic body. Furthermore, the influences of age and gender on the skeletal topography were investigated. Three hundred CT scans of patients without pelvic injury were analysed to record the angle of the pubic body (APB) with respect to the coronal plane, and the depth of the pubic body (DPB) in the sagittal plane. Mean APB and DPB were 54.69° and 55.35mm, respectively. Females had a significantly higher mean APB than males (57.29° vs. 52.41° p<0.001), whereas males had a significant larger mean DPB (59.13mm vs. 51.03mm p<0.001). Age had no effect on the mean APB. Mean width of the pubic body at the base was 9.38mm. The anatomy of this region is reliable in terms of angles and sizes a drill angle of 55° with respect to the operating table will allow maximal screw length, which should be in the region of 55mm. The mean width of the pubic body should allow for placement of a 3.5 or 4.5mm diameter screw.
Location: Romania
Location: Romania
No related grants have been discovered for Lucian Solomon.