ORCID Profile
0000-0001-8870-6216
Current Organisation
Hannover Medical School
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Publisher: Ovid Technologies (Wolters Kluwer Health)
Date: 09-2011
Publisher: Ovid Technologies (Wolters Kluwer Health)
Date: 2011
Publisher: Wiley
Date: 04-2011
DOI: 10.1002/JOR.21429
Abstract: Our objectives were to detect factors that influence the accuracy of surgical navigation (magnitude of deformity, plane of deformity, position of the navigation bases) and compare the accuracy of infrared with electromagnetic navigation. Human cadaveric femora were used. A robot connected with a computer moved one of the bony fragments in a desired direction. The bases of the infrared navigation (BrainLab) and the receivers of the electromagnetic device (Fastrak-Pohlemus) were attached to the proximal and distal parts of the bone. For the first part of the study, deformities were classified in eight groups (e.g., 0 to 5(°)). For the second part, the bases were initially placed near the osteotomy and then far away. The mean absolute differences between both navigation system measurements and the robotic angles were significantly affected by the magnitude of angulation with better accuracy for smaller angulations (p < 0.001). The accuracy of infrared navigation was significantly better in the frontal and sagittal plane. Changing the position of the navigation bases near and far away from the deformity apex had no significant effect on the accuracy of infrared navigation however, it influenced the accuracy of electromagnetic navigation in the frontal plane (p < 0.001). In conclusion, the use of infrared navigation systems for corrections of small angulation-deformities in the frontal or sagittal plane provides the most accurate results, irrespectively from the positioning of the navigation bases.
Publisher: Elsevier BV
Date: 10-2014
DOI: 10.1016/J.INJURY.2014.05.039
Abstract: Intraoperative determinations of femoral antetorsion and leg length during fixation of femoral shaft fractures present a challenge. In femoral shaft fracture fixations, a computer-navigation system has shown promise in determining antetorsion and leg length discrepancies. This retrospective cohort study aimed to determine whether the use of computer navigation during femoral nailing procedures reduced postoperative femoral malrotation and leg length discrepancy, as well as the number of revision cases. We also sought to determine whether radiation exposure time was reduced when computer navigation was used. Of 246 patients treated for femoral shaft fractures between 2004 and 2012, we selected those that received postoperative computed tomography for rotation and leg length control. We included 24 patients who received navigation-assisted treatments and 48 who received unassisted treatments, matched for age, sex, and fracture type. All patients were treated by femoral nailing. The groups showed significant differences in the mean (standard deviation (SD) delay before surgery (navigation-assisted vs. unassisted groups: 8.5 ± 3.2 vs. 5.2 ± 5.8 days P<0.05) and surgery times (163.7 ± 43.94 vs. 98.3 ± 28.13 min P<0.001). The groups were significantly different in the mean (SD) radiation exposure time (4.43 ± 1.35 vs. 3.73 ± 1.5 min P=0.042), and were not significantly different in the postoperative femoral antetorsion difference (8.83 ± 5.52° vs. 12.4 ± 9.2° P=0.056), or in the postoperative length discrepancy (0.92 ± 0.75 vs. 0.95 ± 0.94 cm P=0.453). Four (16.7%) navigation-assisted and 15 (31.25%) unassisted surgeries got revision for torsion and/or length corrections. Our results showed that, compared to unassisted femoral surgery, the computer-navigation system did not improve postoperative results or reduce radiation exposure. In the future, improvements in handling and application could facilitate the workflow and may provide better postoperative results. Currently, computer navigation may provide advantages for complicated or sophisticated cases, such as complex three-dimensional deformity corrections. Level III.
Publisher: Springer Science and Business Media LLC
Date: 09-11-2012
DOI: 10.1007/S00402-012-1639-8
Abstract: Patellar dislocation is a common knee injury with mainly lateral dislocations, leading to ruptures of the medial patellofemoral ligament in most of the cases. Even though several prognostic factors for patellofemoral instability have been identified so far, the appropriate therapy for patients with patellar dislocation remains a controversial issue. The purpose of this study was to compare the outcome after conservative or operative treatment in patients after first-time patellar dislocation. This randomized controlled clinical trial was designed multicentric including patients from six German orthopaedic and trauma departments. Twenty patients with a mean age of 24.6 years with first-time traumatic patella dislocation were included and randomized into either a conservative arm or an operative arm. Plain X-ray images of the knee joint (a.p. and lateral view and tangential view of both patellae) were performed in all cases prior to therapy to exclude osteochondral fragments requiring refixation. An MRI was recommended, but not compulsory. Patients were consulted after 6, 12, and 24 months with a questionnaire including the criteria of the Kujala score, recurrent dislocation, and satisfaction. The mean Kujala score of the conservative vs operative treatment group was 78.6 vs 80.3 after 6 months (p = 0.842), 79.9 vs 88.9 after 12 months (p = 0.165), and 81.3 vs 87.5 after 24 months (p = 0.339). Redislocation rate after 24 months was 37.5 % in the conservative group and 16.7 % in the operative group (p = 0.347). Due to the small number of patients that could be included, no significant difference between the groups could be detected. We see a tendency towards better results after operative treatment. Our multicentric prospective randomized controlled trial revealed no significant difference between conservative and operative treatment for patients after first-time traumatic patellar dislocation. However, a tendency towards a better Kujala score and lower redislocation rates for patients with operative treatment was observed. The small number of patients is a limiting factor of the study, leading to results without statistical significance. A meta-analysis including other study's level I data is desirable for the future.
Publisher: Elsevier BV
Date: 11-2012
Publisher: Springer Science and Business Media LLC
Date: 11-05-2011
DOI: 10.1007/S00256-011-1185-4
Abstract: Various methods have been described to define the femoral neck and distal tibial axes based on a single CT image. The most popular are the Hernandez and Weiner methods for defining the femoral neck axis and the Jend, Ulm, and bimalleolar methods for defining the distal tibial axis. The purpose of this study was to calculate the intra- and interobserver reliability of the above methods and to determine intermethod differences. Three physicians separately measured the rotational profile of 44 patients using CT examinations on two different occasions. The average age of patients was 36.3 ± 14.4 years, and there were 25 male and 19 female patients. After completing the first two sessions of measurements, one observer chose certain cuts at the levels of the femoral neck, femoral condylar area, tibial plateau, and distal tibia. The three physicians then repeated all measurements using these CT cuts. The greatest interclass correlation coefficients were achieved with the Hernandez (0.99 intra- and 0.93 interobserver correlations) and bimalleolar methods (0.99 intra- and 0.92 interobserver correlations) for measuring the femoral neck and distal tibia axes, respectively. A statistically significant decrease in the interobserver median absolute differences could be achieved through the use of predefined CT scans only for measurements of the femoral condylar axis and the distal tibial axis using the Ulm method. The bimalleolar axis method underestimated the tibial torsion angle by an average of 4.8° and 13° compared to the Ulm and Jend techniques, respectively. The methods with the greatest inter- and intraobserver reliabilities were the Hernandez and bimalleolar methods for measuring femoral anteversion and tibial torsion, respectively. The high intermethod differences make it difficult to compare measurements made with different methods.
Publisher: Springer Science and Business Media LLC
Date: 30-03-2011
DOI: 10.1007/S00167-011-1482-4
Abstract: The effect of the rotational alignment of lower extremities on the tibiofemoral contact mechanics is not known. This study was designed to measure the contact area and pressure within medial and lateral tibiofemoral compartments following controlled serial rotational deformities through femoral and tibial shafts. Eight lower extremities of fresh frozen cadavers were used. Computed tomography was conducted to measure the rotational profile of the lower extremities. Through a medial parapatellar arthrotomy, pressure sensors were implanted into both tibiofemoral compartments. Femoral and tibial mid-shaft osteotomies were performed and stabilized by non-locked intramedullary nails and external fixators in neutral rotation. The contact area and pressure were measured under axial loading in neutral rotation and following serial malrotations from 40° external to 40° internal malrotation in 10° increments. Contact area was not affected by malrotations. Medial compartment contact pressure rose with external and decreased with internal malrotations whether femoral or tibial (P < 0.0001) while lateral pressure was not affected. When correlated with the cadavers' original rotational profile, decreased femoral neck anteversion was associated with increased medial pressure up to 28.5% at 20° of retroversion while it decreased with increased anteversion. On the other hand, decreased tibial torsion angle was associated with decreased medial pressure up to -32% at 10° of internal torsion and it increased with excessive external torsion. Furthermore, there was a strong positive correlation with the total rotational alignment as measured by the neck malleolar angle. A significant interaction could be detected between the rotational alignment of the lower extremity and medial tibiofemoral compartment contact pressures.
Publisher: Wiley
Date: 28-02-2012
DOI: 10.1002/RCS.1424
Abstract: The purpose of this study is to present a new navigation device for deformity correction surgery and to evaluate its accuracy compared with a conventional electromagnetic navigation system in tracking the orientation of synthetic bony fragments. This system consists of three sensors and software which can be installed on any personal computer. One sensor is mounted about 1 m above the other sensors. The remaining two sensors are fixed to the bone fragments using Schanz screws. Data from all three sensors are computed using the software to estimate the change in position of the sensors. For the first part of the study 118 planned one and two plane deformities in 5° increments were created. For the second part of the study complex random 3-dimensional deformities were created (300 valid measurements). The mean absolute differences between measurements of the electromagnetic and mini-navigator were 1.8 ± 1.9° in the coronal, 1.1 ± 1.1° in the sagittal and 0.8 ± 0.7° in the transverse plane. Absolute differences between mini-navigator and Fastrak measurements were significantly affected by the magnitude of the deformity (P < 0.0001) with better accuracy for lower deformities. We believe that this new technology is appealing, because of its high accuracy and lower planned costs compared with conventional navigation devices.
Publisher: Springer Science and Business Media LLC
Date: 14-02-2014
DOI: 10.1007/S00402-014-1938-3
Abstract: Successful outcome after total knee arthroplasty (TKA) requires precise realignment of the mechanical axis. The intraoperative assessment of the mechanical axis is difficult. Intraoperatively, the effect of weight bearing on the lower limb mechanical axis is ignored. We developed a custom-made mechanical loading device to simulate weight-bearing conditions intraoperatively and analysed its effect on the mechanical axis during TKA. Measurements of the mechanical axis were obtained during 30 consecutive primary TKAs in osteoarthritic patients using image-free knee navigation system. Half body weight was applied intraoperatively using our device to quantify the effect of intraoperative load application on the mechanical axis, thus receiving indirect information about soft tissue balancing. Furthermore, the intraobserver and interobserver reliability of navigated mechanical axis measurement with and without load was determined. Before TKA, mean mechanical axis was 4.0° ± 4.9° without load. Under loading conditions, the mean change of the mechanical axis was 2.1° ± 2.8°. Repetitive measurements of the senior surgeon and junior surgeon revealed a high intraobserver (ICC 0.997) and interobserver reliability (ICC 0.998). The registration of the mechanical axis without and with application of intraoperative loading demonstrated no significant differences during insertion of the trial components (SD 0.29 ± 0.29) and after the definitive component cementation (SD 0.63 ± 0.44). Intraoperative quantification and analysis of the mechanical lower limb axis applying defined axial loading by our custom-made loading apparatus is reliable. Ligament stability was unbalanced before TKA and balanced after TKA. For TKA, intraoperative simulation of weight bearing may be helpful to quantify, control and correct knee stability and its influence of mechanical axis.
Publisher: Springer Science and Business Media LLC
Date: 25-02-2011
DOI: 10.1007/S00113-010-1944-Z
Abstract: Press-fit fixation of hamstring tendon autografts for anterior cruciate ligament reconstruction is an interesting technique because no hardware is necessary. This study compares the biomechanical properties of press-fit fixations to an interference screw fixation. Twenty-eight human cadaveric knees were used for hamstring tendon explantation. An additional bone block was harvested from the tibia. We used 28 porcine femora for graft fixation. Constructs were cyclically stretched and then loaded until failure. Maximum load to failure, stiffness and elongation during failure testing and cyclic loading were investigated. The maximum load to failure was 970±83 N for the press-fit tape fixation (T), 572±151 N for the bone bridge fixation (TS), 544±109 N for the interference screw fixation (I), 402±77 N for the press-fit suture fixation (S) and 290±74 N for the bone block fixation technique (F). The T fixation had a significantly better maximum load to failure compared to all other techniques (p<0.001). This study demonstrates that a tibial press-fit technique which uses an additional bone block has better maximum load to failure results compared to a simple interference screw fixation.
Publisher: Springer Science and Business Media LLC
Date: 15-01-2013
Publisher: Wiley
Date: 23-03-2015
DOI: 10.1002/JOR.22793
Abstract: High tibial osteotomy (HTO) is a commonly used surgical technique for treating moderate osteoarthritis (OA) of the medial compartment of the knee by shifting the center of force towards the lateral compartment. Previous studies have documented the effects of HTO on the biomechanics of the knee. However, the effects of the procedure on the contact pressures within the ankle joint have not been as well described. Seven cadavers underwent an HTO procedure with sequential 5° valgus realignment of the leg up to 15° of correction. An axial force of up to 550 N was applied and the intraarticular pressure was recorded. Minor valgus realignment of the proximal tibia does not significantly alter the biomechanics of the ankle. However, moderate-to-large changes in proximal tibial alignment result in significantly decreased tibiotalar contact surface area and in changes in intraarticular ankle pressures. These findings are clinically relevant, as they provide a biomechanical rationale for the diagnosis and treatment of ankle symptoms in the setting of lower limb malalignment or after alignment correction procedures.
Publisher: Informa UK Limited
Date: 03-2021
DOI: 10.2147/OAEM.S289070
Publisher: Elsevier BV
Date: 02-2011
DOI: 10.1016/J.INJURY.2010.06.016
Abstract: Mechanically activated intramedullary lengthening nails are advantageous over external fixator. However, difficulties with the control of the distraction rate are the main drawbacks, which may in turn cause insufficient bone regenerate. A total of 57 lengthening procedures were performed using intramedullary skeletal kinetic distractor (ISKD) nail in 53 patients (femoral = 45 and tibial = 12). Average length gain was 4.3 ± 1.6 cm. The cause of shortening was post-traumatic (n = 33), congenital (n = 20), post-tumour resection (n = 1), cosmetic femoral lengthening (n = 2) and post-correction of distal femoral varus deformity (n = 1). The desired lengthening was achieved in all patients. The mean follow-up period was 23 ± 12 months. The healing index for patients with normal bone healing was 1.2 ± 0.32 months/cm. Complications in femoral lengthening were superficial wound infection (n = 1), premature consolidation (n = 4) and insufficient bone regenerate (n = 11), while in the tibial lengthening, two developed equinus contractures,one had compartment syndrome following implantation of the nail and one insufficient bone regenerate.Furthermore, nine runaway nails and three non-distracting nails were present in the femoral lengthening.One non-distracting nail responded to manipulation under anaesthesia, one required exchange nailing and accidental acute lengthening of 3 cm took place while manipulating the third nail. Patients with femoral lengthening and those with insufficient regenerate had significantly higher distraction rates (P = 0.006 and 0.003, respectively). Six out of the nine runaway nails developed insufficient bone regenerate. In addition,10.7-mm tibial ISKD nails were found to have lower rates of runaway nails compared with other used diameters. We emphasise the rule of distraction rates above 1.5 mm/day in the development of insufficient bone regenerate. Distraction problems with these nails are mostly due to dysfunction within the ratcheting mechanism, which may be related to the diameter of the nail. New designs for mechanically activated nails with a better control mechanism for the distraction rate are required.
Publisher: Springer Science and Business Media LLC
Date: 22-06-2011
DOI: 10.1007/S00167-011-1584-Z
Abstract: A secure tibial press-fit technique in posterior cruciate ligament reconstructions is an interesting technique because no hardware is necessary. For anterior cruciate ligament (ACL) reconstruction, a few press-fit procedures have been published. Up to the present point, no biomechanical data exist for a tibial press-fit posterior cruciate ligament (PCL) reconstruction. The purpose of this study was to characterize a press-fit procedure for PCL reconstruction that is biomechanically equivalent to an interference screw fixation. Quadriceps and hamstring tendons of 20 human cadavers (age: 49.2 ± 18.5 years) were used. A press-fit fixation with a knot in the semitendinosus tendon (K) and a quadriceps tendon bone block graft (Q) were compared to an interference screw fixation (I) in 30 porcine femora. In each group, nine constructs were cyclically stretched and then loaded until failure. Maximum load to failure, stiffness, and elongation during failure testing and cyclical loading were investigated. The maximum load to failure was 518 ± 157 N (387-650 N) for the (K) group, 558 ± 119 N (466-650 N) for the (I) group, and 620 ± 102 N (541-699 N) for the (Q) group. The stiffness was 55 ± 27 N/mm (18-89 N/mm) for the (K) group, 117 ± 62 N/mm (69-165 N/mm) for the (I) group, and 65 ± 21 N/mm (49-82 N/mm) for the (Q) group. The stiffness of the (I) group was significantly larger (P = 0.01). The elongation during cyclical loading was significantly larger for all groups from the 1st to the 5th cycle compared to the elongation in between the 5th to the 20th cycle (P < 0.03). All techniques exhibited larger elongation during initial loading. Load to failure and stiffness was significantly different between the fixations. The Q fixation showed equal biomechanical properties compared to a pure tendon fixation (I) with an interference screw. All three fixation techniques that were investigated exhibit comparable biomechanical properties. Preconditioning of the constructs is critical. Clinical trials have to investigate the biological effectiveness of these fixation techniques.
Publisher: Elsevier BV
Date: 11-2015
DOI: 10.1016/J.INJURY.2015.05.040
Abstract: Callus distraction of the femur using an intramedullary distractor has several advantages over the use of external fixators. However, difficulty in controlling the mechanical axis during lengthening may cause deformities and knee osteoarthritis. Purpose of the study is to answer the following questions: (1) is lengthening with an intramedullary device associated with a medial or lateral shift of the mechanical axis? (2) Which factors are associated with varisation/valgisation of the mechanical axis during lengthening? We analysed pre-treatment and post-treatment radiographs from 20 patients who underwent unilateral femoral-lengthening procedures using intramedullary distractors. Patients with acute correction of pre-existing deformities or combined ipsilateral femoral and tibial lengthening were excluded. Mechanical axis deviations, osteotomy level, and nail-medullary canal ratio were recorded. Compared to the preoperative axis, the mechanical axis shifted medially in 7 patients (varisation group) and laterally in 13 patients (valgisation group). The groups did not significantly differ regarding preoperative leg length discrepancy (LLD), mechanical axis alignment, LLD-cause and implants used. The nail-medullary canal ratio significantly differed between groups (p<0.001), being 85% in the valgisation group. The distance between the lesser trochanter and the osteotomy site was significantly longer in the valgisation group (58.9±16.3mm, middle third of the femur) compared to the varisation group (40.6±11.4mm, proximal third of the femur p=0.02). The nail-medullary canal ratio should be considered during preoperative planning. To avoid a varisation effect-for ex le, in cases with pre-existing varus alignment-it would be advisable to perform an osteotomy at the middle third of the femur with implantation of a nail that fully covers the medullary canal at the osteotomy site. Level IV, therapeutic study. See Instructions for Authors for a complete description of levels of evidence.
Publisher: Springer Science and Business Media LLC
Date: 28-12-2011
DOI: 10.1007/S00402-011-1452-9
Abstract: There is a large variety of ruptures of tendons and ligaments in trauma surgery. Reliable data about the most appropriate suture technique and suture material for ruptured tendons are sparse. This human cadaveric study compares the biomechanical properties of three suture materials and three suture techniques for semitendinosus tendon repair. Sixty-three human cadaver hamstring tendons underwent tenotomy and repair with either Baseball suture, Kessler suture, or a novel "Hannover" suture, using either PDS 2-0, Ethibond 2-0, or Fiberwire 2-0. Biomechanical analysis included pretensioning the constructs with 2 N for 50 s, then cyclic loading of 500 cycles between 2 and 15 N at 1 Hz in a servohydraulic testing machine with measurement of elongation. After this, ultimate failure load and failure mode analysis was performed. Ruptures repaired by Fiberwire™ as suture material and the Baseball suture technique were able to withstand significantly higher maximum failure loads (72.8 ± 22.0 N, p < 0.001) than the Kessler suture and the Hannover suture, while ruptures repaired by Fiberwire and the Kessler suture technique showed the lowest elongation after cyclic loading (14.6 ± 3.8 mm, p = 0.15). These findings may be of relevance for the future clinical treatment of tendon ruptures. Further in vivo clinical application studies are desirable for the future.
Publisher: Springer Science and Business Media LLC
Date: 11-02-2009
DOI: 10.1007/S00104-009-1671-6
Abstract: Up to 3% of patients receiving unfractioned heparin develop heparin-induced thrombocytopenia (HIT). We report on a polytrauma patient who developed severe HIT with bilateral pulmonary embolism. Lepirudin treatment resulted initially in rapid improvement. Ten days after discharge the patient complained of abdominal pain. A large subcapsular hepatic hematoma was diagnosed, requiring repeat surgery and ending in secondary sclerosing cholangitis. This process can potentially be avoided by regular tests of lepirudin concentration and coagulation.
Publisher: SAGE Publications
Date: 09-12-2015
Abstract: The Latarjet technique is a reliable treatment option for recurrent anterior shoulder instability. However, the complication rate has been reported to be as high as 30%, with 1.6% of patients suffering a nerve injury. The all-arthroscopic Latarjet procedure has been gaining popularity, even as it has introduced its own challenges. Given that the surgeon is not able to palpate the nerves, their localization and protection can be difficult. Additionally, the use of different instruments can lead to distinct nerve injury mechanisms. To describe the anatomic trajectory of the musculocutaneous, axillary, and suprascapular nerves in relation to the arthroscopic Latarjet approach. Using this information, guidance is provided for reducing nerve injuries during instrumentation and screw insertion. Descriptive laboratory study. A total of 50 cadaveric shoulders from 25 whole-body specimens were examined. The specimens were placed in the beach-chair position, and the deltopectoral and dorsal approaches were used to expose the relevant structures. A subscapularis muscle split was performed between the inferior and middle thirds of the tendon. Digital caliper measurements were taken between various points of the trajectories of the nerves and surrounding anatomic landmarks. The location of the nerves relative to the split was recorded. The musculocutaneous nerve lay within the split in 66% of the shoulders (n = 33) it was medial to the split in 28% (n = 14) it was found lateral to split in 2% (n = 1) and it was not identified in 4% of shoulders (n = 2). The mean length of the axillary nerve was 4.0 cm (95% CI, 3.7-4.2) from the exit of the plexus to the quadrangular space. The axillary nerve was found to be within the split in 50% of the shoulders (n = 25) and medial to the split in the remaining 50% (n = 25). The suprascapular nerve at the level of the supraspinatous fossa passed 3.3 cm (95% CI, 3.1-3.5) medial to the superior rim of the posterior glenoid. The nerve curves around the root of the spine at the spinoglenoid notch level, approximating the glenoid rim to a distance of 2.1 cm (95% CI, 2.0-2.2). Finally, the nerve runs medially again before branching out into smaller fibers to innervate the infraspinatus muscle at a distance of 2.9 cm (95% CI, 2.7-3.1) from the inferior glenoid rim. Based on these findings, there is an approximately 2 cm–wide safe zone from the edge of the glenoid rim for the insertion of graft-fixing screws. When performing a subscapularis split in the arthroscopic Latarjet procedure, the risk of injuries to the musculocutaneous and axillary nerves could be reduced by aiming the switching stick inserted through the posterior portal toward the lateral edge of the intended location of the split. Injuries to the suprascapular nerve could be prevented by aiming the graft-fixing screws laterally toward the edge of the glenoid rim. This study clarifies the location of the nerves relevant to the arthroscopic Latarjet technique and provides anatomic information that could help the surgeon reduce the risk of injuries to the musculocutaneous, axillary, and suprascapular nerves.
Publisher: Ovid Technologies (Wolters Kluwer Health)
Date: 05-2010
Publisher: Wiley
Date: 19-10-2012
DOI: 10.1002/RCS.1464
Abstract: Malrotation after femoral nailing is a common problem, yet estimation of the correct rotation during nailing remains a technical challenge. In the current study, a novel technique was developed for determining femoral antetorsion, the anterior cortical angle (ACA) method. The ACA is the angle between a line along the anterior aspect of the femoral neck and the posterior condylar line of the distal femur. The principal advantage of this method is that it facilitates intra-operative assessment of femoral antetorsion by utilizing the positional technology integrated in smartphones. This measurement is directly comparable to measurements made using computed tomography (CT) scans. The objective of the current study was to investigate the possibility and to validate the feasibility and accuracy of the new method and compare the results obtained with the traditional methods of antetorsion estimation via CT and surgical navigation technology. Twelve cadaveric femora were used. Femoral antetorsion was measured with the ACA method, using a smartphone with integrated gyroscope (Apple IPhone, Cupertino, CA, USA) and by a conventional navigated technique (Brainlab, Feldkirchen, Germany). Subsequently, all femora underwent CT scanning to measure their respective antetorsion via the ACA and the method of Jend (1986). Next, a mid-diaphyseal osteotomy was performed and the distal fragment was rotated and were adjusted to 10-15° using ACA by smartphone. All measurements were repeated with this new position of the femoral fragments. Both radiological measurements according ACA and Jend (1986) demonstrated a statistically significant correlation (intact femur, r = 0.773, p = 0.003 after fixation, r = 0.898, p < 0.001). Comparing the measurements derived from the ACA, as analysed on CT images, and that gleaned from the experimental use of the same method with the smartphone, a statistically significant correlation was also demonstrated (intact femur, r = 0.826, p = 0.001 after fixation, r = 0.932, p < 0.001). Comparing the navigation system and the ACA measured by smartphone there was, on intact femora, a fair correlation without statistical significance and after fixation a good correlation with statistical significance (intact femur, r = 0.467, p = 0.126 after fixation, r = 0.869, p = 0.001). The ACA method generated acceptable results and could contribute to improving the results of femoral nailing. The use of this device in a real clinical setting is necessary to truly elucidate its utility.
Publisher: Springer Science and Business Media LLC
Date: 05-05-2013
Publisher: Springer Science and Business Media LLC
Date: 22-07-2010
Publisher: Elsevier BV
Date: 03-2014
DOI: 10.1016/J.INJURY.2013.10.034
Abstract: The aim of this study was to check the feasibility and accuracy of measuring antetorsion during surgery using a mobile image intensifier (IF) with computed tomography (CT) function (ISO-C 3D Siemens, Erlangen, Germany) in comparison to a conventional multi-slice CT scanner (LightSpeed QX/I CT GE Healthcare, VA, USA). A total of 10 intact femora with intact soft tissue of five fresh frozen cadavers were used. After fixation on a surgical table, IF CT scans of the hip and knee were performed at both 190° and 120° of scanning rotation. Afterwards, a conventional CT scan was performed. Antetorsion was calculated according to the method of Jend et al. Analysis of variance (ANOVA) and Lin's concordance correlation coefficient (LCC) were used to test the agreement between the three measurement techniques. There was no significant difference in femoral antetorsion angle measurements between the different techniques (P>0.05). The mean time required to perform a scan using the ISO-C 3D was 9±3 min. The mean time required to measure antetorsion was 8±2 min. We found a high positive correlation between CT-based measurements and measurements performed using both the ISO-C 3D at 190° (LCC=0.99 mean difference=0.02°±1.8°) and the ISO-C 3D at 120° (LCC=0.99 mean difference=0.6°±1.5°), and a high positive correlation was also seen between both ISO-C 3D methods (LCC=0.99 mean difference=0.6°±1.7°). Measuring femoral antetorsion using an intra-operative IF with CT function is a feasible and accurate method. This technique could be used when there is doubt about the antetorsion angle in the operated femur and it could help decrease the need for a separate revision surgery.
Publisher: Elsevier BV
Date: 2013
Publisher: Springer Science and Business Media LLC
Date: 09-06-2010
DOI: 10.1007/S00402-010-1129-9
Abstract: The long-term outcomes following femoral and tibial segment transports are not well documented. Purpose of the study is to compare the complication rates and life quality scores of femoral and tibial transports in order to find what are the complication rates of femoral and tibial monorail bone transports and if they are different? We retrospectively analyzed the medical records of 8 femoral and 14 tibial consecutive segment transports performed with the monorail technique between 2001 and 2008 in our institution. Mean follow-up was 5.1 ± 2.1 years with a minimum follow-up of 2 years. Aetiology of the defects was posttraumatic in all cases. Four femoral (50%) and nine tibial (64%) fractures were open. The Short Form-36 (SF-36) health survey was used to compare the life quality after femoral and tibial bone transports. The Mann-Whiney U test, Fisher exact test, and the Student's two tailed t-test were used for statistical analysis. P ≤ 0.05 was considered to be statistically significant. The tibial transport was associated with higher rates of severe complications and additional procedures (1.5 ± 0.9 vs. 3.4 ± 2.7, p = 0.048). Three patients of the tibial group were utated because of recurrent infections and one developed a complete regenerate insufficiency that was treated with partial diaphyseal tibial replacement. Contrary to that none of patients of the femoral group developed a complete regenerate insufficiency or was utated. Tibial bone transports have a higher rate of complete and incomplete regenerate insufficiency and can more often end in an utation. The authors suggest systematic weekly controls of the CRP value and of the callus formation in patients with posttraumatic tibia bone transports. Further comparative studies comparing the results of bone transports with and without intramedullary implants are necessary.
Publisher: Springer Science and Business Media LLC
Date: 04-09-2012
DOI: 10.1007/S00167-012-2190-4
Abstract: Double-bundle ACL reconstruction has been demonstrated to be at least as effective as single-bundle reconstruction in terms of restoring knee rotational and translational stability. Until now, the influence on knees with hyperextension has not been evaluated. It was the purpose of this study to evaluate whether double-bundle ACL reconstruction restricts extension in hyperextendable knees. Hamstring tendon reconstructions of 10 human cadaveric knees with the ability of hyperextension (age: 48 ± 14 years) were performed as single bundle (SB) on one side and double bundle (DB) on the other side. A surgical navigation system (BrainLab, Germany) was used to assess the kinematics of each knee at the intact and reconstructed state. A difference with regard to the anterior-to-posterior translation (AP) and rotational stability at 30° of knee flexion, 90° of flexion and the hyperextension capability of each specimen was analysed. The difference in AP translation before and after the reconstruction was not significantly different in 30° and 90° of flexion (n.s). Both single- and double-bundle reconstructions restored the preoperative kinematics at 30° and 90° of knee flexion (n.s). The knee extension was 4° ± 1.8° with the intact ACL and 4° ± 1.7° after reconstruction in the SB group (n.s). The knee extension was 5° of hyperextension ± 1.1° with the intact ACL and 0° ± 0.4° after reconstruction in the DB group the limitation of the extension was significantly larger in this group (p = 0.013). Both single- and double-bundle ACL reconstruction techniques are capable of restoring knee anteroposterior and rotational stability. Double-bundle reconstructions significantly reduce knee extension in knees with hyperextension capability. Care must be taken when using double-bundle techniques in patients with knee hyperextension as this procedure may limit the knee extension after double-bundle ACL reconstruction.
Publisher: Springer Science and Business Media LLC
Date: 17-06-2012
DOI: 10.1007/S00113-012-2167-2
Abstract: A secure tibial press fit technique in posterior cruciate ligament reconstructions may be a relevant alternative to common techniques because no hardware is necessary. Up to the present point in time no biomechanical data exist for a tibial press fit posterior cruciate ligament (PCL) reconstruction. This study compares the biomechanical properties of hamstring and quadriceps tendon grafts using a press fit technique with those of an interference screw fixation. Quadriceps and hamstring tendons of 20 human cadavers (age 49.2±18.5 years) were used. A press fit fixation with a knot in the semitendinosus tendon (K) and a quadriceps tendon bone block graft (Q) were compared to an interference screw fixation (I) in 27 porcine tibiae. In each group, nine constructs were cyclically stretched and then loaded until failure. Maximum load to failure, stiffness and elongation during failure testing and cyclical loading were investigated. The maximum load to failure was 518±157 N (387-650 N) for the K group, 558±119 N (466-650 N) for the I group and 620±102 N (541-699 N) for the Q group. The stiffness was 55±27 N/mm (18-89 N/mm) for the K group, 117±62 N/mm (69-165 N/mm) for the I group and 65±21 N/mm (49-82 N/mm) for the Q group. The stiffness of the I group was significantly larger (ANOVA on ranks, P=0.01). The elongation during cyclical loading was significantly larger for all groups from the 1st to the 5th cycle compared to the elongation in between the 5th and the 20th cycle (P<0.03). All techniques exhibited larger elongation during initial loading. Load to failure and stiffness were significantly different between the fixations. The Q fixation showed equal biomechanical properties compared to a pure tendon fixation (I) with an interference screw. The results of group K were inferior. All three investigated fixation techniques exhibit comparable biomechanical properties. Preconditioning of the constructs is critical. Future randomized, clinical trials have to investigate the biological effectiveness of these fixation techniques.
Publisher: Springer Science and Business Media LLC
Date: 04-03-2014
DOI: 10.1007/S00402-014-1964-1
Abstract: Accurate restoration of mechanical alignment is an important factor in reconstructive surgery of the lower extremity. Conventional intraoperative methods, such as using an electrocautery cable, provide only a momentary evaluation of alignment. In this study, we evaluated a novel technique using a laser emitter, which projected the mechanical axis of the lower extremity, providing continuous intraoperative information on alignment. Alignment of 16 cadaver lower extremities was measured using the electrocautery cable method, the laser method, and CT scan as the standard measurement. The mechanical axis was defined by a line from the center of the femoral head to the center of the ankle. For simplifying measurements the intersection with the tibial plateau was ided into percentages from the medial border (0 %) to the lateral border (100 %). For using the laser method a laser emitting and laser catching device was developed, which is positioned and centered on the femoral head and the ankle using an image intensifier. By catching the laser on the knee region the actual mechanical axis is marked. The data demonstrated good correlation of the laser method when compared to the cable method (P = 0.44). Comparison of the average mechanical axis between cable method and CT (P = 0.819) and laser method and CT (P = 0.647) did not show a statistically significant difference. Average radiation time in comparison between cable method and laser method showed a statistically significant difference (P = 0.013), with the laser method requiring more radiation time. Determination of the mechanical axis during surgery remains a difficult clinical problem. Restoration of alignment is an important prognostic factor for surgical outcome. Based on these data, the laser method represents a simple, yet effective tool for continuous intraoperative evaluation of lower extremity alignment.
Publisher: Springer Science and Business Media LLC
Date: 04-11-2014
DOI: 10.1007/S00402-014-2098-1
Abstract: Cranial migration of shoulder hemiarthroplasties due to rotator cuff insufficiency typically requires conversion into a reverse total shoulder arthroplasty. This study was conducted to analyze differences between the height and offset of six implants designed to enable conversion of a hemiarthroplasty into a reverse system. Anteroposterior radiographs of 40 shoulders were taken. An image analyzing software was used to simulate the implantation of the hemiprostheses. Then the implant was dissembled, leaving on the stem within the humeral shaft. Finally, the implantation of a reverse system was simulated using the stem in the same position. Values are reported as ∆-height and ∆-offset ± standard deviation. Significance was assumed for P < 0.05. The least decrease in height was determined for Implantcast with 11.6 ± 3.3 mm, followed by DePuy (16 ± 5.7 mm) and the greatest for Tornier with 33 ± 5.3 mm. No significant differences were found among Exactech, Mathys and Zimmer. The largest offset-deviation was calculated for DePuy (-21.7 ± 3.7 mm) and the smallest for Implantcast (-3.3 ± 2.8 mm) and Tornier (1.5 ± 5.7 mm). Due to the modular stem, the system of Implantcast can be converted in a reverse system with the least changes in height and offset. For the other manufacturers it does not seem possible to convert a hemiprosthesis to a reversed prosthesis without accepting additional tension of the deltoid muscle. Further experimental studies have to analyze the changes in deltoid abduction moments after conversion of a hemi- into a reversed prosthesis.
Publisher: Springer Science and Business Media LLC
Date: 09-05-2012
DOI: 10.1007/S00167-012-2037-Z
Abstract: Patellar dislocation usually occurs to the lateral side, leading to ruptures of the medial patellofemoral ligament (MPFL) in about 90 % of all cases. Reliable prognostic factors for the stability of the patellofemoral joint after MPFL surgery and satisfaction of the patient have not been established as yet. This multicentric study retrospectively included 40 patients with a mean age of 22.4 ± 8.1 years (range 9-48) from 5 German Trauma Departments with first-time traumatic patellar dislocation and operative treatment. Surgery was limited to soft tissue repairs, and a preoperative magnetic resonance imaging (MRI) was performed in all cases. Evaluation of the MRI included sulcus angle, dysplasia of the trochlea, depth and facet asymmetry of the trochlea, Insall-Salvati index, Tibial tuberosity to trochlear groove (TTTG) distance, and rupture patterns of the MPFL. Patients were interrogated after 2 years about recurrent dislocation, satisfaction, and the Kujala score. Trochlea facet asymmetry was significantly lower in patients with redislocation (23.5 ± 18.8) than in patients without redislocation (43.1 ± 16.5, p = 0.03). Patients with a patellar-based rupture were significantly younger (19.5 ± 7.2 years) than patients without patellar-based rupture (25.4 ± 8.1 years, p < 0.02). Patients with femoral-based ruptures were significantly older (25.7 ± 9.2 years) than patients without femoral-based rupture (19.7 ± 6.1 years, p < 0.02), and had a significantly higher TTTG distance (10.2 ± 6.9 vs. 4.5 ± 5.5, p < 0.02). Patients with incomplete ruptures of the MPFL had a significantly lower Insall-Salvati index (1.2 ± 0.2 vs. 1.4 ± 0.2, p = 0.05). The Kujala score in patients with redislocations was significantly lower (81.0 ± 10.5 points) than in patients without redislocation (91.9 ± 9.2 points, p < 0.02). Younger patients more often sustain patellar-based ruptures following first-time traumatic patella dislocation, while older patients more often sustain femoral-based ruptures of the MPFL. Incomplete MPFL ruptures are correlated with lower Insall-Salvati indices. Low trochlear facet asymmetry is correlated with higher rates of redislocation. These results may be of relevance for the operative and postoperative treatment in the future. Prognostic study, Level IV.
Publisher: Springer Science and Business Media LLC
Date: 27-02-2019
DOI: 10.1007/S00167-019-05414-5
Abstract: There is a paucity of evidence regarding mid- to long-term clinical outcomes of arthroscopic repair of humeral avulsion of the glenohumeral ligament (HAGL). This study investigated clinical outcomes, return to sport and the frequency of associated shoulder lesions. Eighteen patients underwent arthroscopic repair of a HAGL lesion between 2008 and 2015. Clinical outcome was evaluated using the Rowe Score, the Quick DASH Score (Q-DASH), the Oxford Shoulder Instability Score (OSIS), the ASES Score and Range of Motion (ROM). Return to sports and associated shoulder lesions were documented. Sixteen patients agreed to complete the shoulder scores and nine patients were available for clinical examination. Median time to follow-up was 59 months (range 16-104). The median Rowe Score and Q-DASH Score improved significantly from 33 to 85 points and 61 to 7 points, respectively (p = 0.001, p = 0.001). The median OSIS and ASES Score were 20 and 91 points. External rotation was significantly reduced compared to the contralateral side (p = 0.011). One recurrent dislocation was reported. No neurologic or vascular complications after surgery were reported. Five out of the nine patients did not return to sports at the same level. Associated shoulder lesions were found in 89% of the cases. Arthroscopic repair of a HAGL lesion is a reliable method to restore shoulder stability with good clinical results. However, limitations in external rotation and a reduction in sporting ability may persist at 59 months follow-up. Concomitant lesions are common. Case series, level IV.
Publisher: Springer Science and Business Media LLC
Date: 21-04-2013
DOI: 10.1007/S00113-013-2376-3
Abstract: Complex ligament injuries can compromise a knee joint and residual conditions comprise stiffness (arthrofibrosis), instability, cartilage damage leading to osteoarthritis and bone deformity. Accurate diagnosis must address the direction and extent of the instability, the severity of any cartilage lesion and an analysis of the axis and bone deformity as well as important cofactors. Therapeutic options are adhesiolysis, ligament reconstruction, cartilage regeneration and axis correction. As a consequence patients mostly profit from the procedure but there is never a return to the functional level that existed before injury.
Publisher: Springer Science and Business Media LLC
Date: 13-01-2018
DOI: 10.1007/S00167-018-4837-2
Abstract: A crucial step of the Latarjet procedure is the fixation of the coracoid process onto the glenoid. Multiple problems associated with the fixation have been described, including lesions of the suprascapular nerve due to prominence of the screw or bicortical drilling. The purpose of the present study was to evaluate whether monocortical fixation, without perforating the posterior glenoid cortex, would provide sufficient graft stability. Coracoid transfer was performed in 14 scapula models (Sawbones Monocortical fixation was a significantly weaker construct than bicortical fixation (median failure load 221 N, interquartile range 211-297 vs. median failure load 423 N, interquartile range 273-497 p = 0.017). Failure was either due to a pullout of the screws from the socket or a fracture of the glenoid. There was no significant difference in the mode of failure between the two groups (n.s.). Monocortical fixation was significantly weaker than bicortical fixation. However, bicortical drilling and overly long screws may jeopardize the suprascapular nerve. Thus, anatomic knowledge about the safe zone at the posterior rim of the glenoid is crucial. Until further research has evaluated, if the inferior stability is clinically relevant, clinicians should be cautious to use a monocortical fixation technique for the coracoid graft.
Publisher: Springer Science and Business Media LLC
Date: 12-08-2014
DOI: 10.1007/S00256-014-1972-9
Abstract: Conventional intraoperative determination of lower limb alignment is essential for orthopedic surgical treatment. Current methods include the cable, alignment rod, and axis board methods. Are there differences in accuracy and reliability? What are the in idual differences in applicability and radiation exposure? Twenty legs from 12 fresh-frozen cadavers were randomly selected. After fixation of the legs, measurements were performed using the cable, alignment rod, and axis board methods. Afterwards, all cadavers were subjected to CT scanning. Intersection of the mechanical leg axis with the tibia plateau was calculated as the percentage of the tibia plateau, beginning at the medial border (0%) and ending at the lateral border (100%). Results are presented as mean ± standard deviation (SD). Compared with CT measurements, differences of the intersection at the tibia plateau were 3.9 ± 8.5% with the cable method, 3.6 ± 7.6% using the alignment rod, and 3.6 ± 9.6% using the axis board. The difference among all measurements was not statistically significant (p = 0.450). The average intersection of the mechanical axis was 43.95 ± 5.15% using the cable method, 43.93 ± 5.49% using the alignment rod, and 43.77 ± 5.92% using the axis board. CT measurements revealed an average intersection of 42.46 ± 5.22%. There was no statistically significant difference among conventional results (p = 0.976). We demonstrated good intraobserver reliability for all three methods (cable method, ICC = 0.97 alignment rod, ICC = 0.95 and axis board, ICC = 0.96). There were no statistically significant differences regarding radiation time (p = 0.349) or dose area product (p = 0.823). All described measurements demonstrated valid measurement of lower limb alignment. With minimal effort, all three methods present a practical and uncomplicated way to control the mechanical axis.
Publisher: Springer Science and Business Media LLC
Date: 06-03-2015
DOI: 10.1007/S00167-015-3553-4
Abstract: Intraoperative fracture of the lateral cortex fractures of the tibia is a potential complication of high tibial osteotomy (HTO), which may result in inadequate rotational alignment of the distal tibia. Our aim was to determine how rotational malalignment of the distal tibial segment distal would affect intraarticular contact pressure distribution in the knee and ankle joints. A medial, L-shaped opening-wedge HTO was performed on seven human lower body specimens. A stainless steel device with integrated load cell was used to axially load the leg. Pressure-sensitive sensors were used to measure intraarticular contact pressures. Intraoperative changes in alignment were monitored in real time using computer navigation. Measurements were performed in the native knee alignment, after 10° and 15° of alignment correction and with the distal tibia fixed at 15° of external rotation. Moderate-to-large alignment changes after medial opening-wedge HTO resulted in a shift in intraarticular contact pressures from the medial compartment of the knee towards the lateral compartment. However, fixation of the distal tibial segment at 15° of external rotation neutralized this intended beneficial effect. In the ankle, external rotation of the distal tibia also caused a reduction in contact pressures and tibiotalar contact area. Malrotation of the distal tibial fragment negates the intended effect of offloading the diseased compartment of the knee, with the contact pressures remaining similar to those of the native knee. Furthermore, malrotation leads to abnormal ankle contact pressures. Care should be taken to ensure appropriate rotational alignment of the distal tibial segment during intraoperative fixation of HTO procedures.
Publisher: Elsevier BV
Date: 11-2011
DOI: 10.1016/J.INJURY.2011.06.004
Abstract: Rotational malalignment is a well-known complication following intramedullary nailing of femoral shaft fractures. The hypothesis of this study is that various modifiable factors, such as position on the surgical table or nailing technique, influence the incidence of torsional abnormalities. For this retrospective study, we analysed the data of 220 consecutive patients with femoral shaft fractures and postoperative torsion-difference computed tomographies (CTs), performed from 2001 to 2009 in our institution. Mean age of the patients was 33±15 years. Average delay to surgery was 8±11 days. The average postoperative neck anteversion difference between both sides was 11±8°. A p value <0.05 was considered to be statistically significant. The average postoperative neck anteversion difference between both sides was not significantly affected from the position of the patient on the surgical table (supine or lateral, p=0.698), the delay till surgery (p=0.989), the nailing technique (antegrade or retrograde, p=0.793 reamed or unreamed, p=0.930), the type of the implant (p=0.885) and the experience of the surgeon (p=0.055). Furthermore, the learning curve regarding this complication was long and not predictable. We could not identify any risk factors that are associated with an increased incidence of torsional deformities, and thus our hypothesis could not be confirmed. The inability to identify such risk factors renders the prevention of this complication particularly problematic. The invention of new techniques for better intra-operative control of the torsion is probably the only solution to further reduce the incidence of postoperative malrotational deformities.
Publisher: Springer Science and Business Media LLC
Date: 30-09-2010
DOI: 10.1007/S00256-010-1039-5
Abstract: A greater understanding of the lower limb geometry is necessary for the correction of lower limb torsional deformities. The purpose of our study was to measure the normal values of knee torsion using CT and to introduce the neck-malleolar angle as an alternative for measuring lower limb torsion. We studied 77 consecutive CT studies performed from 2007 to 2009 in our clinic. In 67 cases, there was evidence of old trauma or surgical intervention to one limb, whereas the contralateral limb was healthy. The remaining 10 patients had no history of trauma or surgical intervention and were available for paired analysis in order to find the normal intrain idual variability. The whole limb, femoral and tibial torsion were measured according to the "Ulm method". Finally, the knee joint rotational angle and the neck-malleolar angle (the angle between the femoral neck axis and the bimalleolar axis) were measured. The average knee joint rotation angle was 2.4 ± 6.4° while the neck-malleolar angle was 13.2 ± 10.2°. Right to left side differences in healthy paired limbs for total limb rotation, knee joint rotation and the neck-malleolar angle were 6.1 ± 4.1°, 3.9 ± 2.8° and 7.5 ± 4.3° respectively. The mean absolute rotational differences between injured and healthy limbs was 14.5 ± 10.1°, whereas the mean absolute neck-malleolar differences amounted to 12.5 ± 9.9° (p = 0.013) indicating that the knee compensates for torsional asymmetries. The neck-malleolar angle takes into consideration the buffering effects of the knee joint in the transverse plane and contributes valuable additional information. Further studies including the long-term results of patients with torsional errors are important.
Publisher: Hindawi Limited
Date: 26-10-2020
DOI: 10.1155/2020/8872419
Abstract: Background. Biomechanical stability assessment of 3 different constructs for proximal fixation of a locking compression plate (LCP) in treating a Worland type C periprosthetic fracture after total shoulder arthroplasty. Methods. 27 Worland type C fractures after shoulder arthroplasty in synthetic humeri were treated with 14-hole LCP that is proximally fixed using the following: (1) 1 × 1.5 mm cerclage wires and 2x unicortical-locking screws, (2) 3 × 1.5 mm cerclage wires, or (3) 2x bicortical-locking attachment plates. Torsional stiffness was assessed by applying an internal rotation moment of 5 Nm and then after unloading the specimen, an external rotation moment of 5 Nm at the same rate was applied. Axial stiffness was assessed by applying a 50 N preload, and then applying a cyclic load of 250 N, then increasing the load by 50 N each time, until a maximum axial load of 2500 N was reached or specimen failure occurred. Results. With regard to internal as well as external rotational stiffness, group 1 showed a mean stiffness of 0.37 Nm/deg and 0.57 Nm/deg, respectively, group 2 had a mean stiffness of 0.51 Nm/deg and 0.39 Nm/deg, respectively, while group 3 had a mean stiffness of 1.34 Nm/deg and 1.31 Nm/deg, respectively. Concerning axial stiffness, group 1 showed an average stiffness of 451.0 N/mm, group 2 had a mean stiffness of 737.5 N/mm, whereas group 3 had a mean stiffness of 715.8 N/mm. Conclusion. Group 3 displayed a significantly higher torsional stiffness while a comparable axial stiffness to group 2.
Publisher: Elsevier BV
Date: 06-2010
Publisher: British Editorial Society of Bone & Joint Surgery
Date: 05-2015
DOI: 10.1302/0301-620X.97B5.35162
Abstract: Unstable pelvic injuries in young children with an immature pelvis have different modes of failure from those in adolescents and adults. We describe the pathoanatomy of unstable pelvic injuries in these children, and the incidence of associated avulsion of the iliac apophysis and fracture of the ipsilateral fifth lumbar transverse process (L5-TP). We retrospectively reviewed the medical records of 33 children with Tile types B and C pelvic injuries admitted between 2007 and 2014 their mean age was 12.6 years (2 to 18) and 12 had an immature pelvis. Those with an immature pelvis commonly sustained symphyseal injuries anteriorly with diastasis, rather than the fractures of the pubic rami seen in adolescents. Posteriorly, transsacral fractures were more commonly encountered in mature children, whereas sacroiliac dislocations and fracture-dislocations were seen in both age groups. Avulsion of the iliac apophysis was identified in eight children, all of whom had an immature pelvis with an intact ipsilateral L5-TP. Young children with an immature pelvis are more susceptible to pubic symphysis and sacroiliac diastasis, whereas bony failures are more common in adolescents. Unstable pelvic injuries in young children are commonly associated with avulsion of the iliac apophysis, particularly with displaced SI joint dislocation and an intact ipsilateral L5-TP. Cite this article: Bone Joint J 2015 97-B:696–704.
Publisher: Springer Science and Business Media LLC
Date: 11-12-2010
DOI: 10.1007/S00113-010-1818-4
Abstract: Acromial fractures are rare but severe complications which can occur during subacromial decompression. We report a case of acromial pseudarthrosis which was discovered belatedly due to persistent pain after several operations. The pseudarthrosis was successfully treated by osteosynthesis with a distal radius plate and implantation of a monocortical bone graft from the iliac crest. Two years after surgery, the fracture has healed and the patient's pain improved significantly. In the constant score the patient achieved postoperatively 58 points compared to 25 points before surgery and 65 points compared to 25 points preoperatively in the subjective shoulder rating system (SSRS). Postoperatively, the patient had a better range of motion with active abduction/adduction of 50/0/25º (30/0/20° preoperatively), outward rotation/inward rotation of 35/0/45º (30/0/30° preoperatively) and anteversion/retroversion of 60/0/35° (35/0/20° preoperatively).
Publisher: Springer Science and Business Media LLC
Date: 06-08-2012
Publisher: Springer Science and Business Media LLC
Date: 25-06-2009
DOI: 10.1007/S00167-009-0835-8
Abstract: The aim of this study was to investigate, to what extent routine preoperative MRI scans could set the indications for knee arthroscopies and reduce the number of diagnostic arthroscopies. For this retrospective cohort study, 1,000 patients who had knee arthroscopies documented in 1994/1995 were compared with 1,000 patients that were treated in 2004/2005. The preoperative diagnoses that gave indications for knee arthroscopy were compared with the intraoperative findings. The congruence of preoperative diagnosis with the intraoperative findings was evaluated comparing both study populations. The number of patients who were referred to orthopaedic trauma surgeons with MRI increased from 24% to 56%. A high congruence of preoperative diagnosis and intraoperative findings was found in 49% in 1994/1995 and 55% in 2004/2005. However, regarding the most important outcome parameter, the number of diagnostic arthroscopies, no improvement was found (3% in both periods). The presented data suggests that MRI scans are not routinely necessary as an indication for knee arthroscopy, as clinical examination and plain radiograph are sufficient. However, MRI scans do allow a more detailed characterization of the expected findings and can therefore be helpful in therapy planning.
Publisher: Springer Science and Business Media LLC
Date: 18-12-2010
DOI: 10.1007/S00256-010-1074-2
Abstract: The purpose of this prospective study was to investigate the practicality, accuracy, and reliability of upright MR imaging as a new radiation-free technique for the measurement of mechanical axis. We used upright MRI in 15 consecutive patients (30 limbs, 44.7 ± 20.6 years old) to measure mechanical axis deviation (MAD), hip-knee-ankle (HKA) angle, leg length, and all remaining angles of the frontal plane alignment according to Paley (mLPFA, mLDTA, mMPTA, mLDTA, JLCA). The measurements were compared to weight bearing full length radiographs, which are considered to be the standard of reference for planning corrective surgery. FDA-approved medical planning software (MediCAD) was used for the above measurements. Intra- and inter-observer reproducibility using mean absolute differences was also calculated for both methods. The correlation coefficient between angles determined with upright MRI and weight bearing full length radiographs was high for mLPFA, mLDTA, mMPTA, mLDTA, and the HKA angle (r > 0.70). Mean interobserver and intraobserver agreements for upright MRI were also very high (r > 0.89). The leg length and the MAD were significantly underestimated by MRI (-3.2 ± 2.2 cm, p < 0.001 and -6.2 ± 4.4 mm, p = 0.006, respectively). With the exception of underestimation of leg length and MAD, upright MR imaging measurements of the frontal plane angles are precise and produce reliable, reproducible results.
Publisher: Springer Science and Business Media LLC
Date: 09-05-2013
DOI: 10.1007/S00113-013-2393-2
Abstract: The incidence of extravasation of contrast medium is reported in the literature to be between 0.2 % and 0.9 %. A rare consequence of this could be compartment syndrome of the affected limb which requires immediate treatment.We report the case of a patient who developed acute compartment syndrome of the forearm after intravenous injection of radiographic contrast medium in a radiovolar vein during a computed tomography (CT) scan for multiple trauma. The clinical symptoms with pain, loss of range of motion and sensitivity functions, measurement of compartment pressure and radiological images confirmed the diagnosis. After emergency dermatofasciotomy of the forearm the full range of motion and sensitivity functions could be restored.
Location: Greece
No related grants have been discovered for Emmanouil Liodakis.