ORCID Profile
0000-0002-9413-0871
Current Organisations
University of Sydney
,
Royal North Shore Hospital
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Publisher: Elsevier BV
Date: 12-2008
DOI: 10.1016/J.ARTH.2007.10.020
Abstract: The most common cause of long-term failure of total hip arthroplasty is osteolysis and aseptic loosening secondary to wear debris. Combinations of hard materials such as ceramic-on-ceramic generate smaller volumes of particulate wear debris than traditional combinations such as metal-on-polyethylene. We describe 2 cases where osteolysis arose in hips with third-generation alumina ceramic-on-ceramic couplings. Periarticular tissue in both cases contained titanium wear debris due to impingement of the neck of the titanium femoral component against the rim of the titanium shell and ceramic debris from edge loading wear (stripe wear) of the ceramic. It is not clear whether the titanium debris, the ceramic debris, or both caused the osteolysis. These cases illustrate that the risk of osteolysis persists, even with third-generation alumina ceramics.
Publisher: SAGE Publications
Date: 02-11-2022
DOI: 10.1177/15563316211051727
Abstract: Background: Incorrect acetabular component positioning in total hip arthroplasty (THA) has been associated with poor outcomes. Computer-assisted hip arthroplasty increases accuracy and consistency of cup positioning compared to conventional methods. Traditional navigation units have been associated with problems such as bulkiness of equipment and reproducibility of anatomical landmarks, particularly in obese patients or the lateral position. Purpose: We sought to evaluate the accuracy of a novel miniature inertial measurement system, the Navbit Sprint navigation device (Navbit, Sydney, Australia), to navigate acetabular component positioning in both the supine and lateral decubitus positions. We also aimed to validate a new method of patient registration that does not require acquisition of anatomical landmarks for navigation. Methods: We performed THA in a cadaveric study in supine and lateral positions using Navbit navigation to record cup position and compared mean scores from 3 Navbit devices for each cup position on post-implantation CT scans. Results: A total of 11 cups (5 supine and 6 lateral) were available for comparison. A difference of 2.34° in the supine direct anterior approach when assessing acetabular version was deemed to be statistically but not clinically significant. There was no statistically significant difference between CT and navigation measurements of cup position in the lateral position. Conclusion: This cadaveric study suggests that a novel inertial-based navigation tool is accurate for cup positioning in THA in the supine and lateral positions. Furthermore, it validates a novel registration method that does not require the identification of anatomical landmarks.
Publisher: SAGE Publications
Date: 09-09-2020
Abstract: Total hip arthroplasty (THA) in patients younger than 50 years poses significant challenges including postoperative limitations of activity and higher failure rates. Sub-par outcomes of hip resurfacing arthroplasty (HRA) in registries remain controversial due to multiple confounders. Favourable HRA results in some studies are often regarded as irreproducible. The aim of this study is to analyse HRA outcomes in a large international cohort. We compiled a database of 11,382 HRA patients ⩽50 years from an international group of 27 experienced HRA centres from 13 countries. 18 different metal-on-metal (MoM) HRA designs were included with a mean follow-up of 7.6 years. Outcomes were implant survivorship, revision rates, causes for revision, clinical scores and metal ion levels. Outcomes were compared between genders, sizes, implant types and pre-operative diagnoses. Overall cumulative Kaplan-Meier survivorship was 88.9% at 22 years (95% CI: 88.3–89.5%). 2 HRA designs (DePuy Articular Surface Replacement (ASR), and Corin Cormet Hip Resurfacing System (CORMET)) led to inferior results while all others yielded similar survivorships. Excluding ASR and CORMET, implant survivorship in 11,063 cases was 95% at 10 years and 90% at 22 years. In men, implant survivorship was excellent: 99% at 10 years and 92.5% at 21 years. In females, implant survivorship was 90% at 10 years and 81.3% at 22 years. The overall revision rate was 3.6% with most common reasons for revision being implant loosening and adverse local tissue reactions. The best survivorship was found in patients with osteoarthritis (95% CI, 92.1–93.3% at 22 years), the poorest was among dysplastic hips (78.3% 95% CI, 76.5–80.1% at 20 years, p 0.001). Comparable revision rates demonstrated here may mitigate some concerns for safety and longevity of MoM HRA implants. Higher demands for activity and functionality in younger patients make HRA a potential alternative to THA.
Publisher: Ovid Technologies (Wolters Kluwer Health)
Date: 18-06-2021
Abstract: The use of computer navigation has been shown to produce more accurate cup positioning when compared with non-navigated total hip arthroplasty (THA), but so far there is only limited evidence to show its effect on clinical outcomes. The present study analyzed data from the Australian Orthopaedic Association National Joint Replacement Registry to assess the impact of computer navigation on the rates of all-cause revision and revision for dislocation following THA. Data for all non-navigated and navigated primary THAs performed for osteoarthritis in Australia from January 1, 2009, to December 31, 2019, were examined to assess the rate of revision. We analyzed the effects of navigation on rate, reason, and type of revision. Hazard ratios (HRs) from Cox proportional hazard models, adjusted for age, sex, and head size, were utilized. Because of known prosthesis-specific differences in outcomes, we performed a further analysis of the 5 acetabular and femoral component combinations most commonly used with navigation. Computer navigation was utilized in 6,912 primary THAs for osteoarthritis, with the use of navigation increasing from 1.9% in 2009 to 4.4% of all primary THAs performed in 2019. There was no difference in the rate of all-cause revision between navigated and non-navigated THAs looking at the entire group. There was a lower rate of revision for dislocation in the navigation THA cohort. The cumulative percent revision for dislocation at 10 years was 0.4% (95% confidence interval [CI], 0.2% to 0.6%) for navigated compared with 0.8% (95% CI, 0.8% to 0.9%) for non-navigated THAs (HR adjusted for age, sex, and head size, 0.46 95% CI, 0.29 to 0.74 p = 0.002). In the 5 component combinations most commonly used with navigation, the rate of all-cause revision was significantly lower when these components were navigated compared with non-navigated. The cumulative percent revision at 10 years for these 5 prostheses combined was 2.4% (95% CI, 1.6% to 3.4%) for navigated compared with 4.2% (95% CI, 4.0% to 4.5%) for non-navigated THAs (HR, 0.64 95% CI, 0.48 to 0.86 p = 0.003). This study showed that the use of computer navigation was associated with a reduced rate of revision for dislocation following THA. Furthermore, in the component combinations most commonly used with navigation there was also a reduction in the rate of all-cause revision. Therapeutic Level III . See Instructions for Authors for a complete description of levels of evidence.
Publisher: Elsevier BV
Date: 05-2021
Publisher: Elsevier BV
Date: 08-2007
DOI: 10.1016/J.ARTH.2006.09.010
Abstract: We performed 33 cementless total hip arthroplasties for arthritis in 27 patients with an established diagnosis of Paget's disease on the acetabular or femoral side of the hip. There were 3 revisions. One stem for aseptic loosening at 55 months, and 2 stems after periprosthetic fractures at 9 and 70 months. Twenty-three cases were available for follow-up at an average of 6.7 years (range, 2-14 years). Harris hip score improved from 56/100 preoperatively (16-98/100) to 90/100 postoperatively (78-100/100). All surviving components were radiographically bone ingrown. Based on our findings, it appears that a cementless total hip arthroplasty can have a good outcome in Paget's disease.
Publisher: Elsevier BV
Date: 12-2012
Publisher: British Editorial Society of Bone & Joint Surgery
Date: 09-2007
DOI: 10.1302/0301-620X.89B9.19282
Abstract: We studied 33 third generation, alumina ceramic-on-ceramic bearings retrieved from cementless total hip replacements after more than six months in situ. Wear volume was measured with a Roundtest machine, and acetabular orientation from the anteroposterior pelvic radiograph. The overall median early wear rate was 0.1 mm 3 /yr for the femoral heads, and 0.04 mm 3 /yr for the acetabular liners. We then excluded hips where the components had migrated. In this stable subgroup of 22 bearings, those with an acetabular anteversion of 15° (seven femoral heads) had a median femoral head wear rate of 1.2 mm 3 /yr, compared with 0 mm 3 /yr for those with an anteversion of ≥15° (15 femoral heads, p 0.001). Even under edge loading, wear volumes with ceramic-on-ceramic bearings are small in comparison to other bearing materials. Low acetabular anteversion is associated with greater wear.
Publisher: British Editorial Society of Bone & Joint Surgery
Date: 06-2014
DOI: 10.1302/0301-620X.96B6.33381
Abstract: We report on 397 consecutive revision total hip replacements in 371 patients with a mean clinical and radiological follow-up of 12.9 years (10 to 17.7). The mean age at surgery was 69 years (37 to 93). A total of 28 patients (8%) underwent further revision, including 16 (4%) femoral components. In all 223 patients (56%, 233 hips) died without further revision and 20 patients (5%, 20 hips) were lost to follow-up. Of the remaining patients, 209 (221 hips) were available for clinical assessment and 194 (205 hips) for radiological review at mean follow-up of 12.9 years (10 to 17.7). The mean Harris Hip Score improved from 58.7 (11 to 92) points to 80.7 (21 to 100) (p 0.001) and the mean Merle d’Aubigné and Postel hip scores at final follow-up were 4.9 (2 to 6), 4.5 (2 to 6) and 4.3 (2 to 6), respectively for pain, mobility and function. Radiographs showed no lucencies around 186 (90.7%) femoral stems with stable bony ingrowth seen in 199 stems (97%). The survival of the S-ROM femoral stem at 15 years with revision for any reason as the endpoint was 90.5% (95% confidence interval (CI) 85.7 to 93.8) and with revision for aseptic loosening as the endpoint 99.3% (95% CI 97.2 to 99.8). We have shown excellent long-term survivorship and good clinical outcome of a cementless hydroxyapatite proximally-coated modular femoral stem in revision hip surgery. Cite this article: Bone Joint J 2014 -B:730–6.
Publisher: Elsevier BV
Date: 02-2006
DOI: 10.1016/J.ARTH.2005.04.029
Abstract: This study examines the early clinical and radiographic results of the first 216 cases of a cementless fixed bearing tibial tray without screw holes in 191 patients. We hypothesize that stable fixation can be achieved without the use of screws. There were 16 cases lost to follow-up, leaving 200 cases with known outcome. The Hospital for Special Surgery knee scores improved from an average preoperative score of 54/100 to 82/100 postoperatively. Three patients had incomplete radiolucent lines involving the medial aspect of the tibial tray. All of the tibial components reviewed radiographically were bone ingrown. We conclude that the tray provides excellent primary stability, allowing early bone ingrowth, free from osteolysis and with good clinical outcomes. All of the tibial components were bone ingrown by radiographic criteria.
Publisher: Elsevier BV
Date: 06-2004
DOI: 10.1016/J.ARTH.2003.09.018
Abstract: Alumina ceramic-on-ceramic bearings perform exceptionally well under standard hip simulator conditions, but in vivo some retrieved bearings have shown an unusual stripe pattern of wear. We studied 16 bearings retrieved from a series of 1,588 cementless hip arthroplasties with third generation alumina ceramic-on-ceramic bearings to characterize the mechanism of stripe wear formation. None of these bearings were retrieved for bearing failure. The average wear volume was 0.4 mm(3) per year in the heads and 0.3 mm(3) per year in the liners. Mapping of wear stripes on the heads and liners showed that the majority do not occur with normal walking instead they probably occur with edge loading when the hip is flexed, such as with rising from a chair or with climbing a high step.
Publisher: Elsevier BV
Date: 12-2017
Publisher: Springer Science and Business Media LLC
Date: 29-05-2010
Publisher: Elsevier BV
Date: 02-2007
Publisher: Elsevier BV
Date: 09-2018
Publisher: Elsevier BV
Date: 03-2022
DOI: 10.1016/J.ARTH.2021.11.028
Abstract: Alumina ceramic-on-ceramic bearings are used in total hip arthroplasty (THA) because of their wear-resistant and inert properties. In this study, we assessed the clinical and radiographic outcomes of patients undergoing primary cementless ceramic-on-ceramic THA at a minimum follow-up of 20 years. A series of 301 consecutive primary THAs in 283 patients were assessed. Clinically, patients were assessed with the modified Harris Hip Score (HHS) and pain questionnaires. Anteroposterior radiographs of the pelvis and lateral radiographs of the hip were used to radiologically assess the implant. Patients were classified as lost to follow-up if they could not be contacted on multiple occasions or did not wish to participate further in this study. At twenty years after operation, 60 patients had died of a cause unrelated to surgery, 16 had experienced complications requiring reoperation, and 100 hips had both clinical assessments and radiographs at a minimum of 20 years of follow-up. The average HHS improved from 56.1 (range: 17-89) before THA to 92.5 (range: 63-100) at the latest follow-up. The classification of the HHS was good or excellent in 96.4% of patients. Only 1.8% of patients still had moderate residual pain at the thigh or groin. Radiographically, all patients demonstrated bony ingrowth but no clinical symptoms of loosening. The overall survival rate of the implants was 94.2% at 20 years with revision for any reason as the end point. Long-Term follow-up in our series showed excellent implant survival, excellent functional outcomes, and minimal late complications. There was no significant radiographic evidence of failure at a minimum of 20 years after THA. Therapeutic Level IV.
Publisher: AME Publishing Company
Date: 04-2020
Publisher: Ovid Technologies (Wolters Kluwer Health)
Date: 14-05-2020
Abstract: This article was updated on September 4, 2020, because of a previous error. On page 1211, in the author affiliation section, “W.L. Walter, MBBS, PhD 3 ” now reads “W.L. Walter, MBBS, PhD 3,4 ,” the affiliation for Dr. Van Onsem that had read “ 3 Specialist Orthopedic Group, The Mater Clinic, North Sydney, New South Wales, Australia” now reads “ 3 Royal North Shore Hospital, St. Leonards, New South Wales, Australia,” and the affiliation for Dr. Walter that had read “ 3 Specialist Orthopedic Group, The Mater Clinic, North Sydney, New South Wales, Australia” now reads “ 3 Royal North Shore Hospital, St. Leonards, New South Wales, Australia” and “ 4 University of Sydney, Sydney, New South Wales, Australia.” An erratum has been published: J Bone Joint Surg Am. 2020 Oct 7 (19):e113 » As we resume elective surgical procedures, it is important to understand what practices and protocols should be altered or implemented in order to minimize the risk of pathogen transfer during the severe acute respiratory syndrome (SARS)-CoV-2 pandemic. » Each hospital and health system should consider their unique situation in terms of SARS-CoV-2 prevalence, staffing capabilities, personal protection equipment supply, and so on when determining how and when to implement these recommendations. » All patients should be screened for SARS-CoV-2 by means of a thorough history and physical examination, as well as reverse transcription-polymerase chain reaction (RT-PCR) testing whenever possible, prior to undergoing elective surgery. » Patients who are currently infected with coronavirus disease 2019 (COVID-19) should not undergo elective surgery. » These guidelines are based on the available scientific evidence, albeit scant. The recommendations have been reviewed and voted on by the expert delegates who produced this document.
Publisher: Elsevier BV
Date: 2010
DOI: 10.1016/J.ARTH.2008.09.023
Abstract: This study reexamines the clinical and radiologic results of the first 216 cases of a cementless fixed-bearing tibial tray without screw holes in 191 patients at 7.6-year follow-up (range, 5-10 years). Mean Hospital for Special Surgery scores improved from 54/100 preoperatively to 84/100 postoperatively. Four tibial baseplates were revised. Five polyethylene inserts were revised. The overall reoperation rate was 12%. Four percent of tibial baseplates had incomplete nonprogressive radiolucent lines involving 1 or 2 of 10 defined zones. Overall tibial osteolysis rate was 4.1%. All tibial components were stable by radiographic technique. We conclude that this tibial tray provides reliable stability without the use of screws at medium-term follow-up. The polyethylene failure rate is a concern.
Publisher: British Editorial Society of Bone & Joint Surgery
Date: 2019
DOI: 10.1302/0301-620X.101B1.BJJ-2018-0434.R1
Abstract: Between 15% and 20% of patients remain dissatisfied following total knee arthroplasty (TKA). The SAIPH knee system (MatOrtho, Surrey, United Kingdom) is a medial ball and socket TKA that has been designed to replicate native knee kinematics in order to maximize the range of movement, stability, and function. This system is being progressively introduced in a stepwise fashion, with this study reporting the mid-term clinical and radiological outcomes. A retrospective review was undertaken of the first 100 consecutive patients with five-year follow-up following SAIPH TKA performed by the senior authors. The data that were collected included the demographics of the patients, clinical findings, the rate of intraoperative ligamentous release, patient-reported outcome measures (PROMS), radiological assessment, complications, and all-cause revision. Revision data were cross-checked with a national registry. A total of 100 TKAs in 92 patients were included. Three patients died (three TKAs) and a further two TKAs were revised. Of the remaining 95 TKAs, five-year follow-up data were available for 81 TKAs (85%) in 87 patients. There were significant improvements in all PROMs and high satisfaction. The mean ROM at final follow-up was from 0° (full extension) to 124° flexion. There were seven major complications (7%): one infection, two deep vein thromboses, one cerebrovascular event, and two patients with stiffness requiring a manipulation under anaesthesia. Two patients required a lateral retinacular release to optimize patellar tracking in valgus knees no additional ligament releases were performed in any patient. Radiological analysis demonstrated no evidence of implant-related complications. These results demonstrate satisfactory clinical and radiological outcomes at five years following a medial ball and socket TKA. The complication and revision rates are consistent with those previously reported for patients undergoing TKA. These results demonstrate the safety and efficacy of the SAIPH Knee TKA system and support its wider use.
Publisher: British Editorial Society of Bone & Joint Surgery
Date: 11-2009
DOI: 10.1302/0301-620X.91B11.22100
Abstract: Dislocation is a common reason for revision following total hip replacement. This study investigated the relationship between the bearing surface and the risk of revision due to dislocation. It was based on 110 239 primary total hip replacements with a diagnosis of osteoarthritis collected by the Australian Orthopaedic Association National Joint Replacement Registry between September 1999 and December 2007. A total of 862 (0.78%) were revised because of dislocation. Ceramic-on-ceramic bearing surfaces had a lower risk of requiring revision due to dislocation than did metal-on-polyethylene and ceramic-on-polyethylene surfaces, with a follow-up of up to seven years. However, ceramic-on-ceramic implants were more likely to have larger prosthetic heads and to have been implanted in younger patients. The size of the head of the femoral component and age are known to be independent predictors of dislocation. Therefore, the outcomes were stratified by the size of the head and age. There is a significantly higher rate of revision for dislocation in ceramic-on-ceramic bearing surfaces than in metal-on-polyethylene implants when smaller sizes (≤ 28 mm) of the head were used in younger patients ( 65 years) (hazard ratio = 1.53, p = 0.041) and also with larger ( 28 mm) and in older patients (≥ 65 years) (hazard ratio = 1.73, p = 0.016).
Publisher: British Editorial Society of Bone & Joint Surgery
Date: 08-2009
DOI: 10.1302/0301-620X.91B8.22129
Abstract: We evaluated 535 consecutive primary cementless total knee replacements (TKR). The mean follow-up was 9.2 years (0.3 to 12.9) and information on implant survival was available for all patients. Patients were ided into two groups: 153 obese patients (BMI ≥ 30) and 382 non-obese (BMI 30). A case-matched study was performed on the clinical and radiological outcome, comparing 50 knees in each group. We found significantly lower mean improvements in the clinical score (p = 0.044) and lower post-operative total clinical scores in the obese group (p = 0.041). There was no difference in the rate of radiological osteolysis or lucent lines, and no difference in alignment. Log rank test for survival showed no significant differences between the groups (p = 0.167), with a ten-year survival rate of 96.4% (95% confidence interval (CI) 92 to 99) in the obese and 98% (95% CI 96 to 99) in the non-obese. The mid-term survival of TKR in the obese and the non-obese are comparable, but obesity appears to have a negative effect on the clinical outcome. However, good results and high patient satisfaction are still to be expected, and it would seem unreasonable to deny patients a TKR simply on the basis of a BMI indicating obesity.
Publisher: Elsevier BV
Date: 06-2013
DOI: 10.1016/J.ARTH.2012.10.025
Abstract: We present a technique of single posterior longitudinal slot femorotomy. This technique allows the expansion of the metaphyseal-diaphyseal region of the proximal femur facilitating extraction of proximally coated uncemented femoral components while leaving the metaphysis and diaphysis intact. Since 1996 we have performed this technique in 18 revision total hip arthroplasties in 15 patients who had x-ray appearance of bony in-growth/on-growth and where found to have solidly ingrown stems at revision surgery. All were revised to a metaphyseally fitting uncemented stem. At mean follow-up of 122.4 months, there were significant improvements in both pain and function. All revised stems achieved stable boney fixation. There were no complications due to this technique. No patient developed a limp or thigh pain postoperatively. There have been no re-revisions of the stem. With appropriate patient selection, this is a simple, reliable, and extensile technique is useful to assist in the extraction of uncemented proximally coated femoral components whether hydroxyapatite-coated or not.
Publisher: Wiley
Date: 20-06-2017
DOI: 10.1002/JOR.23589
Publisher: Elsevier BV
Date: 03-2014
Publisher: Elsevier BV
Date: 05-2013
Publisher: Elsevier BV
Date: 05-2021
Publisher: American Medical Association (AMA)
Date: 09-06-2023
DOI: 10.1001/JAMANETWORKOPEN.2023.17838
Abstract: Ischemic heart disease remains the leading cause of mortality following hip and knee arthroplasty. Due to its antiplatelet and cardioprotective properties, aspirin has been proposed as an agent that could reduce mortality when used as venous thromboembolism (VTE) prophylaxis following these procedures. To compare aspirin with enoxaparin in reducing 90-day mortality for patients undergoing hip or knee arthroplasty procedures. This study was a planned secondary analysis of the CRISTAL cluster randomized, crossover, registry-nested trial performed across 31 participating hospitals in Australia between April 20, 2019, and December 18, 2020. The aim of the CRISTAL trial was to determine whether aspirin was noninferior to enoxaparin in preventing symptomatic VTE following hip or knee arthroplasty. The primary study restricted the analysis to patients undergoing total hip or knee arthroplasty for a diagnosis of osteoarthritis only. This study includes all adult patients (aged ≥18 years) undergoing any hip or knee arthroplasty procedure at participating sites during the course of the trial. Data were analyzed from June 1 to September 6, 2021. Hospitals were randomized to administer all patients oral aspirin (100 mg daily) or subcutaneous enoxaparin (40 mg daily) for 35 days after hip arthroplasty and 14 days after knee arthroplasty procedures. The primary outcome was mortality within 90 days. The between-group difference in mortality was estimated using cluster summary methods. A total of 23 458 patients from 31 hospitals were included, with 14 156 patients allocated to aspirin (median [IQR] age, 69 [62-77] years 7984 [56.4%] female) and 9302 patients allocated to enoxaparin (median [IQR] age, 70 [62-77] years 5277 [56.7%] female). The mortality rate within 90 days of surgery was 1.67% in the aspirin group and 1.53% in the enoxaparin group (estimated difference, 0.04% 95% CI, −0.05%-0.42%). For the subgroup of 21 148 patients with a nonfracture diagnosis, the mortality rate was 0.49% in the aspirin group and 0.41% in the enoxaparin group (estimated difference, 0.05% 95% CI, −0.67% to 0.76%). In this secondary analysis of a cluster randomized trial comparing aspirin with enoxaparin following hip or knee arthroplasty, there was no significant between-group difference in mortality within 90 days when either drug was used for VTE prophylaxis. anzctr.org.au Identifier: ACTRN12618001879257
Publisher: British Editorial Society of Bone & Joint Surgery
Date: 07-2012
DOI: 10.1302/0301-620X.94B7.29115
Abstract: We analysed 54 alumina ceramic-on-ceramic bearings from total hip replacements retrieved at one centre after a mean duration of 3.5 years (0.2 to 10.6) in situ. These implants were obtained from 54 patients (16 men and 38 women) with a mean age of 67 years (33 to 88) who underwent revision for a variety of reasons. Posterior edge loading was found in the majority of these retrievals (32 out of 54). Anterosuperior edge loading occurred less often but produced a higher rate of wear. Stripe wear on the femoral heads had a median volumetric wear rate of 0.2 mm 3 /year (0 to 7.2). The wear volume on the femoral heads corresponded to the width of edge wear on the matching liner. Anteversion of the acetabular component was found to be a more important determinant than inclination for wear in ceramic bearings. Posterior edge loading may be considered to be a normal occurrence in ceramic-on-ceramic bearings, with minimal clinical consequences. Edge loading should be defined as either anterosuperior or posterior, as each edge loading mechanism may result in different clinical implications.
Publisher: Elsevier
Date: 2009
Publisher: British Editorial Society of Bone & Joint Surgery
Date: 04-2010
DOI: 10.1302/0301-620X.92B4.22967
Abstract: The survivorship of contemporary resurfacing arthroplasty of the hip using metal-on-metal bearings is better than that of first generation designs, but short-term failures still occur. The most common reasons for failure are fracture of the femoral neck, loosening of the component, osteonecrosis of the femoral head, reaction to metal debris and malpositioning of the component. In 2008 the Australian National Joint Registry reported an inverse relationship between the size of the head component and the risk of revision in resurfacing hip arthroplasty. Hips with a femoral component size of ≤ 44 mm have a fivefold increased risk of revision than those with femoral components of ≥ 55 mm irrespective of gender. We have reviewed the literature to explore this observation and to identify possible reasons including the design of the implant, loading of the femoral neck, the orientation of the component, the production of wear debris and the effects of metal ions, penetration of cement and vascularity of the femoral head. Our conclusion is that although multifactorial, the most important contributors to failure in resurfacing arthroplasty of the hip are likely to be the design and geometry of the component and the orientation of the acetabular component.
Publisher: British Editorial Society of Bone & Joint Surgery
Date: 12-2013
DOI: 10.1302/0301-620X.95B12.30917
Abstract: We report the clinical and radiological outcomes of a series of contemporary cementless ceramic-on-ceramic total hip replacements (THRs) at ten years in patients aged ≤ 55 years of age. Pre- and post-operative activity levels are described. A total of 120 consecutive ceramic cementless THRs were performed at a single centre in 110 patients from 1997 to 1999. The mean age of the patients at operation was 45 years (20 to 55). At ten years, four patients had died and six were lost to follow-up, comprising ten hips. The mean post-operative Harris hip score was 94.7 (55 to 100). Radiological analysis was undertaken in 90 available THRs of the surviving 106 hips at final review: all had evidence of stable bony ingrowth, with no cases of osteolysis. Wear was undetectable. There were four revisions. The survival for both components with revision for any cause as an endpoint was 96.5% (95% confidence interval 94.5 to 98.7). The mean modified University of California, Los Angeles activity level rose from a mean of 6.4 (4 to 10) pre-operatively to 9.0 (6 to 10) at the ten-year post-operative period. Alumina ceramic-on-ceramic bearings in cementless primary THR in this series have resulted in good clinical and radiological outcomes with undetectable rates of wear and excellent function in the demanding younger patient group at ten years. Cite this article: Bone Joint J 2013 -B:1603–9.
Publisher: Elsevier BV
Date: 02-2006
DOI: 10.1016/J.ARTH.2005.03.044
Abstract: This article presents 6-year mean (2-12-year) clinical and radiographic follow-up of 62 proximally porous-coated modular S-ROM femoral revisions. These patients come from 106 consecutive cases in 97 patients performed by one surgeon between 1987 and 1992 without structural allograft (femoral bone loss was Paprosky types 1-3B). In the 99 cases with known outcome, there were 7 postoperative complications: 2 dislocations (2%), 2 deep infections (2%), 2 periprosthetic femoral fractures (2%), and 1 transient sciatic nerve palsy (1%). There was only 1 revision of the index surgery for a problem related to the stem (dislocation). Of the 62 stems, 59 (95%) with complete follow-up were ingrown, 2 (3%) were loose, and 1 had stable fibrous fixation. This represents a mechanical failure rate of 5%. Stems greater than 16 mm in diameter were more likely to show stress shielding (P = .009) and not to be ingrown (P = .0006).
Publisher: Elsevier BV
Date: 09-2000
Publisher: SAGE Publications
Date: 28-09-2022
DOI: 10.1177/15563316211034850
Abstract: Despite growing evidence supporting the evaluation, classification, and treatment of acetabular bone loss in revision hip replacement, advancements have not been systematically incorporated into a single document, and therefore, a comprehensive review of the treatment of severe acetabular bone loss is needed. The Stavros Niarchos Foundation Complex Joint Reconstruction Center at Hospital for Special Surgery held an Acetabular Bone Loss Symposium on June 21, 2019, to answer the following questions: What are the trends, emerging technologies, and areas of future research related to the evaluation and management of acetabular bone loss in revision hip replacement? What constitutes the optimal workup and management strategies for acetabular bone loss? The 36 international experts convened were ided into groups, each assigned to discuss 1 of 4 topics: (1) preoperative planning and postoperative assessment (2) implant selection, management of osteolysis, and management of massive bone loss (3) the treatment challenges of pelvic discontinuity, periprosthetic joint infection, instability, and poor bone biology and (4) the principles of reconstruction and classification of acetabular bone loss. Each group came to consensus, when possible, based on an extensive literature review. This document provides an overview of these 4 areas, the consensus each group arrived at, and directions for future research.
Publisher: Elsevier BV
Date: 09-2014
DOI: 10.1016/J.ARTH.2014.04.033
Abstract: 1420 primary cementless THRs with a minimum follow-up of 10-years were stratified according to BMI: non-obese (BMI<30kg/m(2)) and obese (BMI≥30kg/m(2)). Median age at surgery was younger in obese patients (P<0.001). We case-matched 82 THRs in obese patients with 162 THRs in non-obese patients. No difference between groups was found in improvement in HHS (P=0.668), satisfaction with surgery (P=0.644), range of movement, prosthesis orientation, or radiological loosening. The obese cohort was further separated into those with a BMI below and above 35. No difference was found between groups in improvement in HHS, satisfaction with surgery, component orientation, or radiological loosening. There was no difference in the incidence of post-operative complications between obese and non-obese patients. After 10-years, the results of THR are not compromised by obesity.
Publisher: Elsevier BV
Date: 06-2007
DOI: 10.1016/J.ARTH.2006.06.018
Abstract: Audible squeaking in total hip replacements with ceramic-on-ceramic bearings is a rare problem. Acetabular component orientation was compared for 17 squeaking hips and 17 matched controls. Ninety-four percent of control hips were in a range of 25 degrees +/- 10 degrees anteversion and 45 degrees +/- 10 degrees inclination, but only 35% of squeaking hips were in this range (P = .0003). Eight hips squeak with bending. Four hips squeak with walking, and 5 hips squeak after prolonged periods of walking. Hips that squeaked with walking had acetabular components that were more anteverted (40 degrees ) than hips that squeaked with bending (19 degrees ) (P = .001) or prolonged walking (18 degrees ) (P = .020). The hips started squeaking after an average of 14 months. Patients with squeaking hips were younger, heavier, and taller than patients with silent hips.
Publisher: Springer-Verlag
Date: 2005
Publisher: Elsevier BV
Date: 09-2017
DOI: 10.1016/J.ARTH.2017.04.037
Abstract: Dislocation is a leading cause of revision after primary total hip arthroplasty (THA). Although more common in the first few years after the procedure, dislocation can occur at any time. This study investigated the difference in late dislocation in ceramic-on-ceramic (CoC) bearings compared with metal-on-polyethylene and ceramic-on-polyethylene bearings in THA. Data were used from the Australian Orthopaedic Association National Joint Replacement Registry, and the cumulative percent revision for dislocation was estimated using the Kaplan-Meier method for the different bearing surfaces. There were 192,275 THAs included in the study with 101,915 metal-on-cross-linked polyethylene (MoXLPE), 30,256 ceramic-on-cross-linked polyethylene (CoXLPE), and 60,104 CoC. The cumulative percent revision for dislocation at 13 years for MoXLPE, CoXLPE, and CoC groups was 1.2 (95% confidence interval [CI], 1.1-1.3), 1.0 (95% CI, 0.7-1.4), and 0.9 (95% CI, 0.8-1.1), respectively. There was an increased risk of revision for dislocation for MoXLPE compared with CoXLPE and CoC. When stratified for head size, there was no difference in the risk of revision for dislocation between MoXLPE, CoXLPE, and CoC in the 28- and 32-mm head sizes. With a head size of 36 mm, MoXLPE had a higher rate of dislocation compared with other materials. Bearing surface has little impact on revision for dislocation.
Publisher: Wiley
Date: 07-10-2015
DOI: 10.1111/ANS.12868
Abstract: Metal-on-metal (MoM) hip resurfacings have been associated with the potential development of metallic debris and its associated pathology. Serum cobalt and chromium levels are a reliable surrogate marker of wear rates in MoM bearings. The aim of the study was to examine the trend in serum metal ion levels in the initial 2-year post-operative period following implantation of the minimally invasive total conservative hip MoM hip resurfacing and to determine whether head size, acetabular component orientation, clinical outcome scores or post-operative range of movement would affect these levels. In this prospective cohort study, serum cobalt and chromium ion levels were measured pre- and post-operatively in 25 patients who underwent minimally invasive total conservative hip MoM hip resurfacing. The results were correlated with acetabular component orientation, head size, outcome scores and post-operative range of movement. The mean serum cobalt and chromium levels at 2 years were 1.2 ppb (0.4-4.4 ppb) and 2.1 ppb (0.7-5.7 ppb). The mean cup inclination was 43° (30°-60°) and anteversion was 18° (1°-47°). There was no clear relationship between serum ions and acetabular component orientation, outcome scores or range of movement. Patients with a head size ≤52 mm had significantly higher metal ion levels (cobalt P = 0.02, chromium P = 0.045). Our preliminary results show all patients had cobalt and chromium levels below those indicating a high-risk implant, suggesting successful early outcome from minimally invasive total conservative hip resurfacing surgery.
Publisher: Elsevier BV
Date: 02-2006
DOI: 10.1016/J.ARTH.2005.06.010
Abstract: Single-stage bilateral total hip arthroplasty can be performed with a completely new sterile setup for the second side or with the same instruments for both sides. The latter could theoretically lead to a higher prevalence of infection in the second side. We retrospectively determined the prevalence of deep infection during the first postoperative year in 271 consecutive patients operated on with different sterile setups (group 1) and 289 patients operated on with the same setup (group 2). There was one deep infection affecting the first side of a patient in group 1. In group 2, there were no deep infections (P is approximately 1.0) and one developed a superficial infection on the second side requiring readmission and intravenous antibiotics. Given the very low prevalence of deep infection of the first and second side (0.2% and 0%, respectively), it would be necessary to analyze more than 2,300 patients in each group to achieve statistical significance. Based on this experience, the use of the same set of instruments for the second side in the operating conditions described in this study appears safe.
Publisher: Ovid Technologies (Wolters Kluwer Health)
Date: 06-2010
DOI: 10.5435/00124635-201006000-00004
Abstract: The incidence of squeaking in hip replacement varies for ceramic-on-ceramic and metal-on-metal bearings, and the implications are not fully understood. Contributing factors may include component malposition, edge loading, impingement, third-body particles, and loss of lubrication. However, squeaking is multifactorial, requiring a certain combination of interaction among patient, surgical, and implant factors. When squeaking is infrequent and function is not impaired, patients should avoid activities that precipitate the squeaking. Surgery is recommended for persistent or troublesome squeaking, severe malpositioning of components, failure of the implants (including fracture), impingement and subluxation, and pain. If necessary, the bearing can be changed during surgery to another ceramic-on-ceramic or to a ceramic-on-polyethylene bearing.
Publisher: Elsevier BV
Date: 03-2019
DOI: 10.1016/J.KNEE.2019.01.008
Abstract: Femoral rotational asymmetry (FRA) is the difference in rotational alignment between the trochlear groove and posterior condyles. We hypothesize that FRA increases as the tibial plateau becomes more varus due to internal rotation of the posterior condyles and external rotation of the trochlear groove to ensure a vertical trochlear groove at 90 Seventy lower limb Computed Tomography (CT) scans were reviewed by two examiners. Comparisons were made between both the sulcus line (SL) and posterior condylar line (PCL) relative to the surgical epicondylar axis (SEA). Femoral and tibial coronal alignment were measured on CT scanograms and 3D reconstructions. Correlation analysis was performed to identify associations between FRA, SL and PCL and the coronal alignment of the tibia and femur. The mean FRA was +2.9° (SL externally rotated to PCL) (-2.4° to +7.7°, SD 2.2 Native femora are frequently rotationally asymmetrical. As the tibial plateau becomes increasingly varus there is an increase in external rotation of the SL and internal rotation of the PCL. The effect is to maintain a more vertical trochlear groove during flexion in the presence of a varus tibia.
Publisher: Elsevier BV
Date: 05-2014
DOI: 10.1016/J.ARTH.2013.10.015
Abstract: We present a long-term follow-up report of 33 cementless total hip arthroplasties in 27 patients who have an established diagnosis of Paget's disease. The medium term results of this series were reported in 2007 (Lusty et al. Journal of Arthroplasty. 2007 :692). Fourteen cases were available for follow-up at an average of 12.3 years (range 10-17). Harris Hip scores improved from 56/100 preoperatively (16-98/100) to 83/100 post operatively (72-90/100). All surviving components were radiographically ingrown. Based on these findings, cementless total hip arthroplasty has a good long-term outcome in Paget's disease.
Publisher: Springer Science and Business Media LLC
Date: 19-08-2015
DOI: 10.1007/S00264-014-2491-Y
Abstract: The aim of this study is to describe the influence of sitting and standing posture on sagittal pelvic inclination in total hip replacement patients to assist with correct acetabular component positioning. Lateral radiographs of the pelvis and lumbar spine in sitting and standing positions were extracted. Pelvic tilt was measured using the vertical inclination of a line from the anterior superior iliac spine (ASIS) to pubic tubercle. Sacral inclination, Cobb angle of the lumbar spine and hip flexion were recorded. Sixty patients were identified with a mean age of 63. Men were more likely to flex the lumbar spine in sitting (p = 0.004) 80° of hip flexion is required for seated posture. Stiff hips required compensatory pelvic flexion and lumbar flexion in sitting. There is a linear relationship between hip flexion and pelvic tilt, hip flexion and lumbar lordosis. Pelvic orientation is determined by lumbar and hip stiffness. This impacts on acetabular version.
Publisher: Springer Science and Business Media LLC
Date: 16-09-2023
DOI: 10.1007/S00264-022-05570-3
Abstract: The ability of kinematic alignment (KA) to consistently restore trochlea anatomy in total knee arthroplasty (TKA) is unknown despite recreation of constitutional anatomy being its rationale for use. The purpose of this study was to assess if alignment choice in TKA effects the ability to restore the native trochlea groove. One hundred and twenty-two consecutive patients undergoing robotic-assisted TKA using the MAKO image-based robotic platform had simulated femoral components placed according to kinematic, mechanical and functional alignment principals. Implant position and trochlea restoration between groups were compared. Restoration was assessed by shift (medial–lateral) and depth relative to the native groove from three consistent points full extension (0°), mid-flexion (30°–40°) and deep flexion (70°–80°). Three hundred and sixty-six alignment options were analysed. Femoral alignment was significantly different between groups. Of KA, 13.1% compared to 3.3% of FA plans were outside safe coronal boundaries. The trochlear groove was translated the most by MA compared to KA and FA (full extension, MA 7.84 ± 1.99 mm lateral to the native groove, KA 6.40 ± 2.43 mm and FA 6.88 ± 1.74 mm, p ≤ 0.001). In full extension, FA most closely restored the trochlear groove depth in all three positions of flexion. Alignment philosophy led to significant differences in trochlea groove recreation. A kinematically placed femoral component led to positioning considered unsafe in over 13% of cases. A functionally placed femoral component most closely restored trochlea depth in all three positions of flexion.
Publisher: Elsevier BV
Date: 04-2004
Publisher: Ovid Technologies (Wolters Kluwer Health)
Date: 03-2022
Publisher: British Editorial Society of Bone & Joint Surgery
Date: 04-2011
DOI: 10.1302/0301-620X.93B4.25707
Abstract: We investigated factors that were thought to be associated with an increased incidence of squeaking of ceramic-on-ceramic total hip replacements. Between June 1997 and December 2008 the three senior authors implanted 2406 primary total hip replacements with a ceramic-on-ceramic bearing surface. The mean follow-up was 10.6 years. The diagnosis was primary osteoarthritis in each case, and no patient had undergone previous surgery to the hip. We identified 74 squeaking hips (73 patients) giving an incidence of 3.1% at a mean follow-up of 9.5 years (4.1 to 13.3). Taller, heavier and younger patients were significantly more likely to have hips that squeaked. Squeaking hips had a significantly higher range of post-operative internal (p = 0.001) and external rotation (p = 0.003) compared with silent hips. Patients with squeaking hips had significantly higher activity levels (p = 0.009). A squeaking hip was not associated with a significant difference in patient satisfaction (p = 0.24) or Harris hip score (p = 0.34). Four implant position factors enabled good prediction of squeaking. These were high acetabular component inclination, high femoral offset, lateralisation of the hip centre and either high or low acetabular component anteversion. This is the largest study to date to examine patient factors and implant position factors that predispose to squeaking of a ceramic-on-ceramic hip. The results suggest that factors which increase the mechanical forces across the hip joint and factors which increase the risk of neck-to-rim impingement, and therefore edge-loading, are those that predispose to squeaking.
Publisher: SAGE Publications
Date: 07-09-2012
Publisher: Elsevier BV
Date: 04-2013
DOI: 10.1016/J.ARTH.2012.07.032
Abstract: The use of large diameter metal bearing total hip arthroplasty (THA) and hip resurfacing arthroplasty (HRA) increased in popularity in the last decade. More recent literature has highlighted the effect of head size in patient outcomes. Data was obtained from the Australian Orthopaedic Association National Joint Replacement Registry (AOA-NJRR) to evaluate the Birmingham (MoM) bearing surface when used with THA and HRA. There is no difference in the overall rate of revision between the THA and HRA but head size has a significant effect on revision rate. The data show that small diameter metal bearings in HRA (below 50mm) have a higher rate of revision than large diameter metal bearings in HRA (equal to and above 50mm) (P<.001). Conversely the large diameter metal bearings in THA have a higher rate of revision than the small diameter metal bearings in THA (P=.027). The revision rate for large diameter HRA compared to small diameter THA is not significantly different P=.670. We recommend caution when choosing either a large diameter (≥50mm) metal on metal THA or small diameter (<50mm) HRA.
Publisher: Springer Science and Business Media LLC
Date: 16-04-2020
Publisher: Ovid Technologies (Wolters Kluwer Health)
Date: 07-12-2011
DOI: 10.2106/JBJS.J.01206
Publisher: Springer Science and Business Media LLC
Date: 08-08-2013
Publisher: SAGE Publications
Date: 26-11-2023
DOI: 10.1177/15563316221136128
Abstract: Background: Pelvic tilt (PT) is described as the pelvic orientation along the transverse axis, yet 4 PT definitions were established based on radiographic landmarks: anterior pelvic plane (PT a ), the center of femoral heads to sacral plate (PT m ), pelvic outlet (PT h ), and sacral slope (SS). These landmarks quantify a similar concept, yet understanding of their relationships is lacking, and their differences are sometimes ignored. Purpose: This study aimed to examine the correlations and differences of PT definitions for education and research purposes. Methods: This study reviewed 105 sagittal pelvic radiographs of patients (68 men and 37 women) awaiting hip surgery at a single clinic. Hip hardware and spine pathologies were examined for subgroup analysis. Two observers annotated 4 PTs in a gender-dependent manner and repeated it after 6 months. The linear regression model and intraclass correlation coefficient (ICC) were applied with a 95% confidence interval. Results: The SS showed no correlation to the other 3 PT definitions, except for females in the hip hardware subgroup (n = 17). PT m demonstrated very strong linear correlation to PT h ( r 0.9) under the linear model PT m = 0.951 × PT h – 68.284. Conclusion: The PT m and PT h can be calculated from each other under a simple linear regression equation, which enables comparisons between them. SS presented poor correlations to the other PT parameters, except for the female subgroup with hip implant that required further analysis PT a -related comparisons showed high anatomical variations between patients.
Publisher: British Editorial Society of Bone & Joint Surgery
Date: 11-2014
DOI: 10.1302/0301-620X.96B11.33698
Abstract: We describe the clinical and radiological results of cementless primary total hip replacement (THR) in 25 patients (18 women and seven men 30 THRs) with severe developmental dysplasia of the hip (DDH). Their mean age at surgery was 47 years (23 to 89). In all, 21 hips had Crowe type III dysplasia and nine had Crowe type IV. Cementless acetabular components with standard polyethylene liners were introduced as close to the level of the true acetabulum as possible. The modular cementless S-ROM femoral component was used with a low resection of the femoral neck. A total of 21 patients (25 THRs) were available for review at a mean follow-up of 18.7 years (15.8 to 21.8). The mean modified Harris hip score improved from 46 points pre-operatively to 90 at final follow up (p 0.001). A total of 15 patients (17 THRs 57%) underwent revision of the acetabular component at a mean of 14.6 years (7 to 20.8), all for osteolysis. Two patients (two THRs) had symptomatic loosening. No patient underwent femoral revision. Survival with revision of either component for any indication was 81% at 15 years (95% CI 60.1 to 92.3), with 21 patients at risk. This technique may reduce the need for femoral osteotomy in severe DDH, while providing a good long-term functional result. Cite this article: Bone Joint J 2014 -B:1449–54.
Publisher: British Editorial Society of Bone & Joint Surgery
Date: 02-2014
DOI: 10.1302/0301-620X.96B2.32784
Abstract: Squeaking arising from a ceramic-on-ceramic (CoC) total hip replacement (THR) may cause patient concern and in some cases causes patients to seek revision surgery. We performed a meta-analysis to determine the incidence of squeaking and the incidence of revision surgery for squeaking. A total of 43 studies including 16 828 CoC THR that reported squeaking, or revision for squeaking, were entered into the analysis. The incidence of squeaking was 4.2% and the incidence of revision for squeaking was 0.2%. The incidence of squeaking in patients receiving the Accolade femoral stem was 8.3%, and the incidence of revision for squeaking in these patients was 1.3%. Cite this article: Bone Joint J 2014 -B:181–7.
Publisher: Elsevier BV
Date: 12-2017
Publisher: Ovid Technologies (Wolters Kluwer Health)
Date: 18-04-2023
Publisher: Elsevier BV
Date: 12-2017
Publisher: Elsevier BV
Date: 02-2007
DOI: 10.1016/J.ARTH.2006.05.034
Abstract: The causes of pain after total hip arthroplasty are multiple. We present a series of 15 patients (16 cases) who presented with pain related to the iliopsoas tendon. All patients had previously undergone cementless hip arthroplasty and presented with similar symptoms and clinical signs. Surgery was carried out after failure of conservative measures. Release of the iliopsoas tendon from the lesser trochanter gave good symptomatic relief in all except one patient who required reposition of acetabular prosthesis, with the average Harris Hip Score improving from 58 (range, 44-70) to 91 (range, 78-95) postoperatively. This relatively uncommon condition should be considered in the differential diagnosis of all patients who present with groin pain after total hip arthroplasty. Surgical release of the iliopsoas tendon can give excellent results in these patients.
Publisher: British Editorial Society of Bone & Joint Surgery
Date: 09-2016
DOI: 10.1302/2046-3758.59.2000507
Abstract: This study aimed to characterise and qualitatively grade the severity of the corrosion particles released into the hip joint following taper corrosion. The 26 cases examined were CoC/ABG Modular (n = 13) and ASR/SROM (n = 13). Blood serum metal ion levels were collected before and after revision surgery. The haematoxylin and eosin tissue sections were graded on the presence of fibrin exudates, necrosis, inflammatory cells and corrosion products. The corrosion products were identified based on visible observation and graded on abundance. Two independent observers blinded to the clinical patient findings scored all cases. Elemental analysis was performed on corrosion products within tissue sections. X-Ray diffraction was used to identify crystalline structures present in taper debris. The CoC/ABG Modular patients had a mean age of 64.6 years (49.4 to 76.5) and ASR/SROM patients had a mean age of 58.2 years (33.3 to 85.6). The mean time in situ for CoC/ABG was 4.9 years (2 to 6.4) and ASR/SROM was 6.1 years (2.5 to 8.1). The blood serum metal ion concentrations reduced following revision surgery with the exception of Cr levels within CoC/ABG. The grading of tissue sections showed that the macrophage response and metal debris were significantly higher for the ASR/SROM patients (p 0.001). The brown/red particles were significantly higher for ASR/SROM (p 0.001). The taper debris contained traces of titanium oxide, chromium oxide and aluminium nitride. This study characterised and qualitatively graded the severity of the corrosion particles released into the hip joint from tapers that had corrosion damage. Cite this article: S. Munir, R. A. Oliver, B. Zicat, W. L. Walter, W. K. Walter, W. R. Walsh. The histological and elemental characterisation of corrosion particles from taper junctions. Bone Joint Res 2016 :370–378. DOI: 10.1302/2046-3758.59.2000507.
Publisher: Elsevier BV
Date: 04-2018
DOI: 10.1016/J.ARTH.2017.11.044
Abstract: Squeaking is an on-going complication with a variable incidence of 0.5%-20.7%. The mechanism of squeaking has not been understood completely and is most likely multifactorial in nature. Previously, we have reported on a squeaking rate of 7.3% at 2 years. Our current results show a substantial increase in the squeaking incidence from 7.3% to 17.4% with the DeltaMotion articulation at the 5-year follow-up. Two hundred six total hip arthroplasties with a large ceramic-on-ceramic bearing were performed on 195 patients by 2 senior authors. The minimum duration of follow-up was 5 years (range 5-6.2). The mean Harris Hip Score remained stable at 91.7 at 5 years compared to 92 after 2 years. However, we observed an increase in the squeaking rate from 7.3% after 2 years to 17.4% after 5 years. As in previous studies, we did not find significant differences between the silent and squeaking group in relation to age, height, weight, and femoral head diameter. In contrast, others reported no significant differences regarding range of motion and gender between the silent and the squeaking hip group at 2 years of follow-up, whereas at 5 years, the squeaking group showed a significantly higher combined range of motion and a higher relative risk of squeaking in women compared to the silent group. While large diameter ceramic bearings may produce squeaking, especially in female patients, our mid-term clinical results of a large ceramic-on-ceramic bearing in total hip arthroplasty are encouraging. Nevertheless, long-term follow-up is recommended.
Publisher: SAGE Publications
Date: 04-2015
Abstract: Intra-operative peri-prosthetic femoral fractures are a significant concern in total hip arthroplasty and can occur at any time during surgery, with the highest incidence during implant insertion. This study combines subject-specific finite element analysis modeling with an optical tracking system to characterize the resultant strain in the bone and results of impaction during total hip replacement surgery. The use of ABG II femoral stem (Stryker Orthopaedics, Mahwah, NJ, USA) in the model yielded the following results. Hammer velocity was measured experimentally using a three-dimensional optical tracking system and these data were input into the finite element analysis model so that intra-operative loading scenario could be simulated. A quasi-static explicit simulation and a dynamic loading step using two implant–bone interface friction (0.1 and 0.4 friction coefficients) states were simulated. The maximum swing velocity of a mallet was experimentally measured at 1.5 m/s and occurred just before impaction of the hammer with implant introducer. Two friction states resulted in different results with the lower friction coefficient generating higher strains in the anterior regions of the model and higher displacement of the implant with respect to the femur when compared to the high friction state.
Publisher: Elsevier BV
Date: 06-2010
Publisher: Medical Journals Sweden AB
Date: 08-2013
Publisher: SAGE Publications
Date: 07-2014
Abstract: We reviewed 380 hip resurfacings cases between December 1999 and Dec 2012. 11 cases (2.89%) squeaked postoperatively. Mean follow-up was 88.6 months (19-130 months). Mean time to squeak was 11.3 months (3-22 months). Ten (91%) cases were male and nine (81%) cases had a Birmingham hip resurfacing. Cases were matched for age, gender, BMI and implant to three controls. Radiographs were analysed using EBRA (Einzel-Bild-Roentgen-Analysis, University of Innsbruck, Austria) software to evaluate cup orientation. There was no significant difference between the mean inclination angle of the cups (p = 0.26) or the mean anteversion angle (p = 0.29). There was no difference in serum cobalt (p = 0.20) or serum chromium (p = 0.45) levels at latest follow-up. Three of the 11 (27.3%) cases had revision surgery at a mean follow-up of 101 months (72-117 months). Squeaking was not influenced by patient demographic parameters and resolved in all cases that did not undergo revision surgery. Males with a resurfacing head size mm had significantly increased odds of squeaking when compared to controls (odds ratio = 26.6 95% CI = 1.2-573.3 p .05). Based on our findings, we do not recommend that squeaking on its own should be an indication for revision of hip resurfacing components.
Publisher: Ovid Technologies (Wolters Kluwer Health)
Date: 16-03-2021
Publisher: Elsevier BV
Date: 12-2005
DOI: 10.1016/J.ARTH.2005.03.039
Abstract: The pumping of fluid and polyethylene wear debris from the joint space to the retroacetabular bone is implicated in the pathogenesis of osteolysis. Three possible mechanisms for this pumping: pressure gradients, diaphragm pumping, and piston pumping were studied in vitro in a laboratory model. The simulated activities of rising from a chair and climbing stairs produced high-pressure gradients and high angles of loading that could pump fluid through the apical hole to the retroacetabular bone. A noncongruent liner acted as a diaphragm pump, producing pressures 6 times higher than that seen with a congruent liner. Pistoning motion of the liner produced pressures 8 times higher than when no pistoning occurs. These pumping mechanisms could be mitigated by the use of acetabular components without holes.
Publisher: Ovid Technologies (Wolters Kluwer Health)
Date: 09-2010
Publisher: EDP Sciences
Date: 2023
Abstract: Background : Navigation in total hip arthroplasty has been shown to improve acetabular positioning and can decrease the incidence of mal-positioned acetabular components. This study aimed to assess two surgical guidance systems by comparing intra-operative measurements of acetabular component inclination and anteversion with a post-operative CT scan. Methods : We prospectively collected intra-operative navigation data from 102 hips receiving conventional THA or hip resurfacing arthroplasty through either a direct anterior or posterior approach. Two guidance systems were used simultaneously: an inertial navigation system (INS) and an optical navigation system (ONS). Acetabular component anteversion and inclination were measured on a post-operative CT. Results : The average age of the patients was 64 years (range: 24–92) and the average BMI was 27 kg/m 2 (range 19–38). 52% had hip surgery through an anterior approach. 98% of the INS measurements and 88% of the ONS measurements were within 10° of the CT measurements. The mean (and standard deviation) of the absolute difference between the postoperative CT and the intra-operative measurements for inclination and anteversion were 3.0° (2.8) and 4.5° (3.2) respectively for the ONS, along with 2.1° (2.3) and 2.4° (2.1) respectively for the INS. There was a significantly lower mean absolute difference to CT for the INS when compared to ONS in both anteversions ( p 0.001) and inclination ( p = 0.02). Conclusions : We found that both inertial and optical navigation systems allowed for adequate acetabular positioning as measured on postoperative CT, and thus provide reliable intraoperative feedback for optimal acetabular component placement. Level of Evidence: Therapeutic Level II.
Publisher: Elsevier BV
Date: 10-2007
DOI: 10.1016/J.ARTH.2007.05.021
Abstract: In the last 10 years, resurfacing hip arthroplasty has become a popular option again for treating hip disorders in younger, active patients in some parts of the world. We report the Australian experience with this operation based on the Australian National Joint Replacement Registry and the literature available on the Australian experience in Resurfacing.
Publisher: Wiley
Date: 12-03-2014
DOI: 10.1002/JOR.22588
Publisher: Wiley
Date: 15-10-2015
DOI: 10.1002/JOR.22741
Abstract: Modular hip implants allows for the adjustment of leg length, offset, and the ability to remove the head for acetabular exposure during primary and revision surgery. The design of the Morse taper facilitates the intimate contact of the conical trunnion of the femoral stem (male component), with the conical bore of the femoral head (female component). Orthopaedic trunnion tapers are not standardized and vary in length, taper angle, and base dimension. Variations in the design and surface characteristics of the trunnion, will directly reflect on the interface at the taper junction and can influence the likelihood of subsequent wear, corrosion and longevity of the implant. The effect of surface topography of trunnions on commercially available hip stems has not yet been considered as a possible contributing factor in the corrosion observed at taper junctions. In this study we analyzed the surface topography and surface roughness of randomly selected commercially available femoral hip stem trunnions to obtain a greater insight into their surface characteristics.
Publisher: Baishideng Publishing Group Inc.
Date: 2015
Publisher: British Editorial Society of Bone & Joint Surgery
Date: 12-2011
DOI: 10.1302/0301-620X.93B12.27529
Abstract: This multicentre study analysed 12 alumina ceramic-on-ceramic components retrieved from squeaking total hip replacements after a mean of 23 months in situ (11 to 61). The rates and patterns of wear seen in these squeaking hips were compared with those seen in matched controls using retrieval data from 33 ‘silent’ hip replacements with similar ceramic bearings. All 12 bearings showed evidence characteristic of edge-loading wear. The median rate of volumetric wear was 3.4 mm 3 /year for the acetabular component, 2.9 mm 3 /year on the femoral heads and 6.3 mm 3 /year for head and insert combined. This was up to 45 times greater than that of previously reported silent ceramic-on-ceramic retrievals. The rate of wear seen in ceramic components revised for squeaking hips appears to be much greater than in that seen in retrievals from ‘silent’ hips.
Publisher: Elsevier BV
Date: 07-2020
Publisher: Elsevier BV
Date: 05-2004
Publisher: Elsevier BV
Date: 09-2006
Publisher: Ovid Technologies (Wolters Kluwer Health)
Date: 11-2008
DOI: 10.2106/JBJS.H.00867
Publisher: British Editorial Society of Bone & Joint Surgery
Date: 2023
DOI: 10.1302/2633-1462.41.BJO-2022-0147.R1
Abstract: Iliopsoas impingement occurs in 4% to 30% of patients after undergoing total hip arthroplasty (THA). Despite a relatively high incidence, there are few attempts at modelling impingement between the iliopsoas and acetabular component, and no attempts at modelling this in a representative cohort of subjects. The purpose of this study was to develop a novel computational model for quantifying the impingement between the iliopsoas and acetabular component and validate its utility in a case-controlled investigation. This was a retrospective cohort study of patients who underwent THA surgery that included 23 symptomatic patients diagnosed with iliopsoas tendonitis, and 23 patients not diagnosed with iliopsoas tendonitis. All patients received postoperative CT imaging, postoperative standing radiography, and had minimum six months’ follow-up. 3D models of each patient’s prosthetic and bony anatomy were generated, landmarked, and simulated in a novel iliopsoas impingement detection model in supine and standing pelvic positions. Logistic regression models were implemented to determine if the probability of pain could be significantly predicted. Receiver operating characteristic curves were generated to determine the model’s sensitivity, specificity, and area under the curve (AUC). Highly significant differences between the symptomatic and asymptomatic cohorts were observed for iliopsoas impingement. Logistic regression models determined that the impingement values significantly predicted the probability of groin pain. The simulation had a sensitivity of 74%, specificity of 100%, and an AUC of 0.86. We developed a computational model that can quantify iliopsoas impingement and verified its accuracy in a case-controlled investigation. This tool has the potential to be used preoperatively, to guide decisions about optimal cup placement, and postoperatively, to assist in the diagnosis of iliopsoas tendonitis. Cite this article: Bone Jt Open 2023 (1):3–12.
Publisher: SAGE Publications
Date: 2005
Publisher: Elsevier BV
Date: 02-2015
DOI: 10.1016/J.ARTH.2014.09.010
Abstract: We analyzed the results of 206 consecutive total hip arthroplasties performed using large diameter ceramic-on-ceramic bearings. At an average follow-up of 28months, the mean Harris Hip Score improved from 54 to 92. Fifteen (7.3%) hips were noted to squeak. There was no significant difference between silent and squeaking hips with regards to age, weight, height, BMI, range of movement, femoral head diameter, leg length, and offset or center of rotation. No correlation was present between incidence of squeaking and increasing cup inclination and anteversion. 5.2% of cups orientated within Lewinnek's safe zone squeaked. No hips required revision for squeaking. While large diameter ceramic bearings may produce squeaking, our early results of surgery using large head ceramic bearings are encouraging. However, long-term follow-up is required.
Publisher: Elsevier BV
Date: 09-2013
Publisher: Elsevier BV
Date: 06-2015
DOI: 10.1016/J.MEDENGPHY.2015.03.012
Abstract: Subject-specific finite element (FE) modeling methodology could predict peri-prosthetic femoral fracture (PFF) for cementless hip arthoplasty in the early postoperative period. This study develops methodology for subject-specific finite element modeling by using the element deactivation technique to simulate bone failure and validate with experimental testing, thereby predicting peri-prosthetic femoral fracture in the early postoperative period. Material assignments for biphasic and triphasic models were undertaken. Failure modeling with the element deactivation feature available in ABAQUS 6.9 was used to simulate a crack initiation and propagation in the bony tissue based upon a threshold of fracture strain. The crack mode for the biphasic models was very similar to the experimental testing crack mode, with a similar shape and path of the crack. The fracture load is sensitive to the friction coefficient at the implant-bony interface. The development of a novel technique to simulate bone failure by element deactivation of subject-specific finite element models could aid prediction of fracture load in addition to fracture risk characterization for PFF.
Publisher: Elsevier BV
Date: 20-11-190728635
Publisher: Springer Science and Business Media LLC
Date: 05-11-2008
Publisher: Elsevier BV
Date: 12-2011
Publisher: Elsevier BV
Date: 06-2008
Publisher: Ovid Technologies (Wolters Kluwer Health)
Date: 2012
DOI: 10.2106/JBJS.J.00331
Publisher: Wiley
Date: 10-1996
DOI: 10.5694/J.1326-5377.1996.TB138587.X
Abstract: Screening for atlantoaxial (C1-2) instability in children with Down syndrome before their participation in sport is called into serious question. Despite the lack of clear supporting data to justify screening, it has been widely recommended and enforced by some sporting organisations for several decades. Experience in New South Wales during the past 25 years strongly suggests that routine screening should be discontinued, and the existing literature supports this move.
Publisher: Elsevier BV
Date: 03-2021
Publisher: British Editorial Society of Bone & Joint Surgery
Date: 02-2012
DOI: 10.1302/0301-620X.94B2.27247
Abstract: We report a case of a male patient presenting with bilateral painful but apparently well-positioned and -fixed large-diameter metal-on-metal hip replacements four years post-operatively. Multiple imaging modes revealed a thick-walled, cystic expansile mass in communication with the hip joint (a pseudotumour). Implant retrieval analysis and tissue culture eliminated high bearing wear or infection as causes for the soft-tissue reaction, but noted marked corrosion of the modular neck taper adaptor and corrosion products in the tissues. Therefore, we believe corrosion products from the taper caused by mismatch of the implant components led to pseudotumour formation requiring revision.
Publisher: Elsevier BV
Date: 03-2010
Publisher: British Editorial Society of Bone & Joint Surgery
Date: 10-2009
DOI: 10.1302/0301-620X.91B10.22544
Abstract: The outcome of total hip replacement (THR) is potentially affected by the body mass index (BMI) of the patient. We studied the outcome of 2026 consecutive primary cementless THRs performed for osteoarthritis. The mean follow-up was 6.3 years (0 to 11.71) and no patient was lost to follow-up for survival analysis. The patients were ided into two groups according to their BMI as follows: non-obese (BMI 30 kg/m 2 ) and obese (BMI ≥ 30 kg/m 2 ). The obese patient undergoing surgery was found to be significantly younger (p 0.001). The log-rank test for equality of survival showed no difference in the mid-term survival (p = 0.552) with an estimated survival at 11 years of 95.2% (95% CI 92.5 to 98.0) in the non-obese and 96.7% (95% CI 94.9 to 98.5) in the obese groups. The clinical and radiological outcome was determined in a case-matched study performed on 134 obese in iduals closely matched with 134 non-obese controls. The non-obese group was found to have a significantly higher post-operative Harris hip score (p 0.001) and an increased range of movement, but overall satisfaction with surgery was comparable with that of the obese patients. Radiological analysis of the acetabular and femoral components showed no significant differences with regard to radiolucent lines, osteolysis, ingrowth of the femoral component, the acetabular inclination angle or alignment of the femoral component. Our results suggest that the survival of cementless THR is not adversely affected by obesity. Obese patients can therefore be counselled that despite a lower clinical score, they should expect to be satisfied with the result of their THR with a mid-term survival rate equivalent to that of non-obese patients.
Publisher: American Medical Association (AMA)
Date: 23-08-2022
Abstract: There remains a lack of randomized trials investigating aspirin monotherapy for symptomatic venous thromboembolism (VTE) prophylaxis following total hip arthroplasty (THA) or total knee arthroplasty (TKA). To determine whether aspirin was noninferior to enoxaparin in preventing symptomatic VTE after THA or TKA. Cluster-randomized, crossover, registry-nested trial across 31 hospitals in Australia. Clusters were hospitals performing greater than 250 THA or TKA procedures annually. Patients (aged ≥18 years) undergoing hip or knee arthroplasty procedures were enrolled at each hospital. Patients receiving preoperative anticoagulation or who had a medical contraindication to either study drug were excluded. A total of 9711 eligible patients were enrolled (5675 in the aspirin group and 4036 in the enoxaparin group) between April 20, 2019, and December 18, 2020. Final follow-up occurred on August 14, 2021. Hospitals were randomized to administer aspirin (100 mg/d) or enoxaparin (40 mg/d) for 35 days after THA and for 14 days after TKA. Crossover occurred after the patient enrollment target had been met for the first group. All 31 hospitals were initially randomized and 16 crossed over prior to trial cessation. The primary outcome was symptomatic VTE within 90 days, including pulmonary embolism and deep venous thrombosis (DVT) (above or below the knee). The noninferiority margin was 1%. Six secondary outcomes are reported, including death and major bleeding within 90 days. Analyses were performed by randomization group. Enrollment was stopped after an interim analysis determined the stopping rule was met, with 9711 patients (median age, 68 years 56.8% female) of the prespecified 15 562 enrolled (62%). Of these, 9203 (95%) completed the trial. Within 90 days of surgery, symptomatic VTE occurred in 256 patients, including pulmonary embolism (79 cases), above-knee DVT (18 cases), and below-knee DVT (174 cases). The symptomatic VTE rate in the aspirin group was 3.45% and in the enoxaparin group was 1.82% (estimated difference, 1.97% 95% CI, 0.54%-3.41%). This failed to meet the criterion for noninferiority for aspirin and was significantly superior for enoxaparin ( P = .007). Of 6 secondary outcomes, none were significantly better in the enoxaparin group compared with the aspirin group. Among patients undergoing hip or knee arthroplasty for osteoarthritis, aspirin compared with enoxaparin resulted in a significantly higher rate of symptomatic VTE within 90 days, defined as below- or above-knee DVT or pulmonary embolism. These findings may be informed by a cost-effectiveness analysis. ANZCTR Identifier: ACTRN12618001879257
Publisher: Ovid Technologies (Wolters Kluwer Health)
Date: 12-2007
DOI: 10.2106/JBJS.F.01466
Publisher: Elsevier BV
Date: 12-2013
Publisher: SAGE Publications
Date: 04-2009
DOI: 10.1177/112070000901900207
Abstract: Fifteen patients (16 hips) with an ankylosed hip joint for a mean of 36 years (3.5 to 65), had their hips converted to a cementless Total Hip Replacement (THR). They were followed-up for a median of 10.75 years (5.0 to 19) with none lost to follow-up. All patients showed improved mobility and function post-operatively. The Harris Hip Score improved from 70 (SEM 3.4) to 83 post-operatively (SEM 4.4), which was statistically significant (p 0.05). There was one acetabular cup revision at 5 years post implantation for aseptic loosening. All other femoral and acetabular components remained clinically and radiographically well fixed. We conclude that a previously ankylosed hip can be effectively converted to a cementless total hip replacement with good long term results.
Publisher: Informa UK Limited
Date: 2022
DOI: 10.2147/MDER.S339669
Publisher: BMJ
Date: 20-05-2014
Publisher: British Editorial Society of Bone & Joint Surgery
Date: 06-2012
DOI: 10.1302/0301-620X.94B6.28801
Abstract: This systematic review of the literature summarises the clinical experience with ceramic-on-ceramic hip bearings over the past 40 years and discusses the concerns that exist in relation to the bearing combination. Loosening, fracture, liner chipping on insertion, liner canting and dissociation, edge-loading and squeaking have all been reported, and the relationship between these issues and implant design and surgical technique is investigated. New design concepts are introduced and analysed with respect to previous clinical experience.
Publisher: Elsevier BV
Date: 02-2004
DOI: 10.1016/J.ARTH.2003.10.005
Abstract: Ten patients who were scheduled for revision for pelvic osteolysis were studied. All had bone-ingrown metal-backed cups with holes and polyethylene liners. Pressures were measured in the osteolytic lesion and in the hip joint while applying cyclic forces across the artificial joint. In 4 cases with lesions that were fully contained by bone, loading of the hip produced a pressure wave in the osteolytic lesion. Cyclic forces, such as those that occur in normal gait, can act on the polyethylene liner, the metal shell, and the supporting bone to pump fluid in the retroacetabular osteolytic lesion. This pumping action may contribute to the pathogenesis of osteolysis by the mechanisms of fluid pressure, fluid flow, or the transportation of wear particles.
Publisher: Elsevier BV
Date: 03-2020
DOI: 10.1016/J.ARTH.2019.10.020
Abstract: Joint stability is one of the goals of any joint replacement. The contribution of prosthesis design to sagittal stability in total knee arthroplasty (TKA) has emerged as an area of interest. The purpose of this study was to evaluate the sagittal stability of four prosthesis types and determine the effect on patient reported outcome measures (PROMs). A matched-cohort cross-sectional study was performed on 60 patients after TKA at 1-year follow-up. Three surgeons performed 10 medially stabilized (MS) TKA and 10 non-MS TKA. Sagittal stability was assessed by a blinded observer using a KT-1000 arthrometer, Lachman's test, and the anterior drawer test. PROMs (Oxford, Knee Injury and Osteoarthritis Outcome Score, Western Ontario and McMaster Universities Osteoarthritis Index, Forgotten joint score) and visual analog scale assessed function and satisfaction. MS TKA had significantly decreased translation on KT-1000 and improved stability compared with non-MS TKA (P < .05). Increased PROMs were demonstrated in the MS TKA group compared with the non-MS TKA group (P < .05). When ided based on objective stability, regardless of the prosthesis type, patients with a stable knee had superior PROMs (P < .05), particularly in sport-related questions. The MS TKA had significantly greater sagittal stability, improved PROMs, and satisfaction compared with non-MS TKA. Independent of prosthesis design, patients with greater sagittal stability demonstrated improved PROMs.
Publisher: Ovid Technologies (Wolters Kluwer Health)
Date: 19-03-2014
DOI: 10.2106/JBJS.L.01625
No related grants have been discovered for Bill Walter.