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58 result(s) for "Beitzel, Knut"
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Slope-reducing tibial osteotomy decreases ACL-graft forces and anterior tibial translation under axial load
Purpose Posterior tibial slope (PTS) represents an important risk factor for anterior cruciate ligament (ACL) graft failure, as seen in clinical studies. An anterior closing wedge osteotomy for slope reduction was performed to investigate the effect on ACL-graft forces and femoro-tibial kinematics in an ACL-deficient and ACL-reconstructed knee in a biomechanical setup. Methods Ten cadaveric knees with a relatively high native slope (mean ± SD): (slope 10° ± 1.4°, age 48.2 years ± 5.8) were selected based on prior CT measurements. A 10° anterior closing-wedge osteotomy was fixed with an external fixator in the ACL-deficient and ACL-reconstructed knee (quadruple Semi-T/Gracilis-allograft). Each condition was randomly tested with both the native tibial slope and the post-osteotomy reduced slope. Axial loads (200 N, 400 N), anterior tibial draw (134 N), and combined loads were applied to the tibia while mounted on a free moving and rotating X–Y table. Throughout testing, 3D motion tracking captured anterior tibial translation (ATT) and internal tibial rotation (ITR). Change of forces on the reconstructed ACL-graft (via an attached load-cell) were recorded, as well. Results ATT was significantly decreased after slope reduction in the ACL-deficient knee by 4.3 mm ± 3.6 ( p  < 0.001) at 200 N and 6.2 mm ± 4.3 ( p  < 0.001) at 400N of axial load. An increase of ITR of 2.3° ±2.8 ( p  < 0.001) at 200 N and by 4.0° ±4.1 ( p  < 0.001) at 400 N was observed after the osteotomy. In the ACL-reconstructed knee, ACL-graft forces decreased after slope reduction osteotomy by a mean of 14.7 N ± 9.8 ( p  < 0.001) at 200 N and 33.8 N ± 16.3 ( p  < 0.001) at 400N axial load, which equaled a relative decrease by a mean of 17.0% (SD ± 9.8%), and 33.1% (SD ± 18.1%), respectively. ATT and ITR were not significantly changed in the ACL-reconstructed knee. Testing of a tibial anterior drawing force in the ACL-deficient knee led to a significantly increased ATT by 2.7 mm ± 3.6 ( p  < 0.001) after the osteotomy. The ACL-reconstructed knee did not show a significant change (n.s.) in ATT after the osteotomy. However, ACL-graft forces detected a significant increase by 13.0 N ± 8.3 ( p  < 0.001) after the osteotomy with a tibial anterior drawer force, whereas the additional axial loading reduced this difference due to the osteotomy (5.3 N ± 12.6 (n.s.)). Conclusions Slope-reducing osteotomy decreased anterior tibial translation in the ACL-deficient and ACL-reconstructed knee under axial load, while internal rotation of the tibia increased in the ACL-deficient status after osteotomy. Especially in ACL revision surgery, the osteotomy protects the reconstructed ACL with significantly lower forces on the graft under axial load.
Current concepts in acromioclavicular joint (AC) instability – a proposed treatment algorithm for acute and chronic AC-joint surgery
Background There exists a vast number of surgical treatment options for acromioclavicular (AC) joint injuries, and the current literature has yet to determine an equivocally superior treatment. AC joint repair has a long history and dates back to the beginning of the twentieth century. Main body Since then, over 150 different techniques have been described, covering open and closed techniques. Low grade injuries such as Type I-II according to the modified Rockwood classification should be treated conservatively, while high-grade injuries (types IV-VI) may be indicated for operative treatment. However, controversy exists if operative treatment is superior to nonoperative treatment, especially in grade III injuries, as functional impairment due to scapular dyskinesia or chronic pain remains concerning following non-operative treatment. Patients with a stable AC joint without overriding of the clavicle and without significant scapular dysfunction (Type IIIA) may benefit from non-interventional approaches, in contrast to patients with overriding of the clavicle and therapy-resistant scapular dysfunction (Type IIIB). If these patients are considered non-responders to a conservative approach, an anatomic AC joint reconstruction using a hybrid technique should be considered. In chronic AC joint injuries, surgery is indicated after failed nonoperative treatment of 3 to 6 months. Anatomic AC joint reconstruction techniques along with biologic augmentation (e.g. Hybrid techniques, suture fixation) should be considered for chronic high-grade instabilities, accounting for the lack of intrinsic healing and scar-forming potential of the ligamentous tissue in the chronic setting. However, complication and clinical failure rates remain high, which may be a result of technical failures or persistent horizontal and rotational instability. Conclusion Future research should focus on addressing horizontal and rotational instability, to restore native physiological and biomechanical properties of the AC joint.
High degree of consensus achieved regarding diagnosis and treatment of acromioclavicular joint instability among ESA-ESSKA members
Purpose To develop a consensus on diagnosis and treatment of acromioclavicular joint instability. Methods A consensus process following the modified Delphi technique was conducted. Panel members were selected among the European Shoulder Associates of ESSKA. Five rounds were performed between October 2018 and November 2019. The first round consisted of gathering questions which were then divided into blocks referring to imaging, classifications, surgical approach for acute and chronic cases, conservative treatment. Subsequent rounds consisted of condensation by means of an online questionnaire. Consensus was achieved when ≥ 66.7% of the participants agreed on one answer. Descriptive statistic was used to summarize the data. Results A consensus was reached on the following topics. Imaging: a true anteroposterior or a bilateral Zanca view are sufficient for diagnosis. 93% of the panel agreed on clinical override testing during body cross test to identify horizontal instability. The Rockwood classification, as modified by the ISAKOS statement, was deemed valid. The separation line between acute and chronic cases was set at 3 weeks. The panel agreed on arthroscopically assisted anatomic reconstruction using a suspensory device (86.2%), with no need of a biological augmentation (82.8%) in acute injuries, whereas biological reconstruction of coracoclavicular and acromioclavicular ligaments with tendon graft was suggested in chronic cases. Conservative approach and postoperative care were found similar Conclusion A consensus was found on the main topics of controversy in the management of acromioclavicular joint dislocation. Each step of the diagnostic treatment algorithm was fully investigated and clarified. Level of evidence Level V.
Patient-specific risk factors for repair failure and poor functional outcome after rotator cuff repair - an umbrella review
Purpose Understanding patient-specific factors that influence postoperative outcomes and failure rates following rotator cuff repair is crucial for surgeons to tailor individualized treatments. The purpose of this umbrella review was to identify preoperatively measurable factors that influence the risk of retear and functional outcomes following rotator cuff repair (RCR). Additionally, the study aimed to evaluate the quality of evidence from systematic reviews and meta-analyses to provide a comprehensive understanding of these predictive factors. Methods A systematic search of the MEDLINE database via PubMed was conducted to identify systematic reviews and meta-analyses reporting preoperatively measurable factors affecting functional outcomes and failure rates following arthroscopic rotator cuff repair. The methodological quality of included reviews was assessed using the AMSTAR checklist. Data synthesis summarized key risk factors, quantified study overlap via Corrected Covered Area (CCA), and examined heterogeneity and publication bias when reported in the reviews. Results Twenty-three systematic reviews, including 11 meta-analyses, met the inclusion criteria, yielding a CCA of 0.403, which reflects moderate overlap. The average AMSTAR score was 7.57, indicating moderate methodological quality. However, only a few reviews included analyses of heterogeneity or publication bias, and the evidence presented was often contradictory. Meta-analyses revealed statistically significant associations between higher retear rates and factors such as advanced age, reduced bone mineral density, elevated body mass index, diabetes, shorter acromiohumeral interval, increased critical shoulder angle, involvement of multiple tendons, greater tendon retraction, longer symptom duration, larger tear size, poor tissue quality, and greater distance from the musculotendinous junction to the glenoid. Genetic analyses provided moderate to strong evidence linking healing failure to mutations in the matrix metallopeptidase 3 (MMP3) and Tenascin C (TNC) genes, as well as a single nucleotide polymorphism (SNP) in the Estrogen Related Receptor β (ESRRβ) gene. Improved tendon healing was associated with the upregulation of the growth factor Bone Morphogenetic Protein 5 (BMP5) and increased expression of collagen type III (COL3). High preoperative expectations consistently correlated with better functional outcomes, whereas other psychological factors, such as concerns and fear avoidance, were associated with poorer outcomes. Conclusion Evidence synthesized in this review underscores the importance of patient age, expectations, and the extent of the rotator cuff tear in influencing outcomes following rotator cuff repair. These factors should be carefully considered in treatment planning for patients undergoing rotator cuff repair.
Repair of the entire superior acromioclavicular ligament complex best restores posterior translation and rotational stability
Purpose The acromioclavicular ligament complex (ACLC) is the primary stabilizer against horizontal translation with the superior ACLC providing the main contribution. The purpose of this study was to evaluate the specific regional contributions in the superior half of ACLC, where the surgeon can easily access and repair or reconstruct, for posterior translational and rotational stability. Methods The superior half of ACLC was divided into three regions; Region A (0°–60°): an anterior 1/3 region of the superior half of ACLC, Region B (60°–120°): a superior 1/3 region of the superior half of ACLC, and Region C (120°–180°): a posterior 1/3 region of the superior half of ACLC. Fifteen fresh-frozen cadaveric shoulders were used. Biomechanical testing was performed to evaluate the resistance force against passive posterior translation (10 mm) and the resistance torque against passive posterior rotation (20°) during the following the four conditions. (1) Stability was tested on all specimens in their intact condition ( n  = 15). (2) The ACLC was dissected and stability was tested ( n  = 15). (3) Specimens were randomly divided into three groups by regions of suturing. Stability was tested after suturing Region A, Region B, or Region C ( n  = 5 per group). (4) Stability was tested after suturing additional regions: Region A + B (0°–120°), Region B + C (60°–180°), or Region A + C (0°–60°, 120°–180°, n  = 5 per group). Results The translational force increased after suturing Region A when compared with dissected ACLC ( P  = 0.025). The force after suturing Region A + B was significantly higher compared to the dissected ACLC ( P  < 0.001). The rotational torque increased after suturing Region A or Region B compared with dissected ACLC ( P  = 0.020, P  = 0.045, respectively). The torque after suturing the Region A + C was significantly higher compared to the dissected ACLC ( P  < 0.001). Conclusion The combined Region A + B contributed more to posterior translational stability than Region B + C or Region A + C. In contrast, combined Region A + C contributed more to posterior rotational stability than Region A + B or Region B + C. Based on these findings, surgical techniques restoring the entire superior ACLC are recommended to address both posterior translational and rotational stability of the AC joint.
Knee arthrodesis versus above-the-knee amputation after septic failure of revision total knee arthroplasty: comparison of functional outcome and complication rates
Background After septic failure of total knee arthroplasty (TKA) and multiple revision operations resulting in impaired function, bone and/or soft-tissue damage a reconstruction with a revision arthroplasty might be impossible. Salvage procedures to regain mobility and quality of life are an above-the-knee amputation or knee arthrodesis. The decision process for the patient and surgeon is difficult and data comparing arthrodesis versus amputation in terms of function and quality of life are scarce. The purpose of this study was to analyse and compare the specific complications, functional outcome and quality of life of above-the-knee amputation (AKA) and modular knee-arthrodesis (MKA) after septic failure of total knee arthroplasty. Methods Eighty-one patients treated with MKA and 32 patients treated with AKA after septic failure of TKA between 2003 and 2012 were included in this cohort study. Demographic data, comorbidities, pathogens and complications such as re-infection, implant-failure or revision surgeries were recorded in 55MKA and 20AKA patients. Functional outcome with use of the Lower-Extremity-Functional-Score (LEFS) and the patients reported general health status (SF-12-questionnaire) was recorded after a mean interval of 55 months. Results A major complication occurred in more than one-third of the cases after MKA and AKA, whereas recurrence of infection was with 22% after MKA and 35% after AKA the most common complication. Patients with AKA and MKA showed a comparable functional outcome with a mean LEFS score of 37 and 28 respectively ( p  = 0.181). Correspondingly, a comparable physical quality of life with a mean physical SF-12 of 36 for AKA patients and a mean score of 30 for MKA patients was observed ( p  = 0.080). Notably, ten AKA patients that could be fitted with a microprocessor-controlled-knee-joint demonstrated with a mean LEFS of 56 a significantly better functional outcome than other amputee patients ( p  < 0.01) or MKA patients ( p  < 0.01). Conclusion Naturally, the decision process for the treatment of desolate situations of septic failures following revision knee arthroplasty is depending on various factors. Nevertheless, the amputation should be considered as an option in patients with a good physical and mental condition.
Radiographic alterations in clavicular bone tunnel width following anatomic coracoclavicular ligament reconstruction (ACCR) for chronic acromioclavicular joint injuries
Purpose To evaluate tunnel widening and its relationship in loss of reduction and clinical outcomes in patients undergoing anatomic coracoclavicular ligament reconstruction (ACCR) using free tendon grafts for chronic acromioclavicular (AC) joint injuries. Methods A retrospective chart review was performed on patients undergoing ACCR for type III–VI AC joint injuries between January 2003 and December 2017. For radiographic analysis, pre- and post-operative coracoclavicular distance (CCD) and tunnel width of the medial and lateral clavicular bone tunnel were measured at the earliest (EPO) and latest postoperative follow-up (LPO). To determine the clinical relevance of improvement in clinical outcome score (American Shoulder and Elbow Surgeons score) substantial clinical benefit (SCB), and patient acceptable symptomatic state (PASS) thresholds were used. Results Twenty-four patients with a mean clinical follow-up of 37 ± 35 months (mean age 44.7 ± 13.4) were included in the study. Both the medial (5.6 ± 0.2 mm EPO –6.6 ± 0.7 mm LPO; p  < 0.001) and lateral (5.6 ± 0.5 mm EPO –6.8 ± 1 mm LPO ; p  < 0.001) clavicular bone tunnel showed significant widening from EPO to LPO. There was a significant loss of reduction at LPO (CCD LPO 10.1 ± 4 mm) compared to EPO (CCD EPO : 6.2 ± 3.8 mm) ( p  < 0.001). No significant correlation between loss of reduction and medial ( p  = 0.45; r  = − 0.06) or lateral ( p  = 0.69; r  = − 0.06) tunnel widening was found. Alterations in tunnel width were shown having no influence on clinical outcomes. Conclusion Patients who underwent ACCR using a free tendon graft for the treatment of chronic type III–VI ACJ injuries showed significant clavicular bone tunnel widening during the postoperative course. No correlation between tunnel widening and loss of reduction was shown with radiographic findings having no influence on clinical benefit and satisfaction. Study design Case Series; Level of evidence, IV.
The acutely injured acromioclavicular joint – which imaging modalities should be used for accurate diagnosis? A systematic review
Background The management of acute acromioclavicular (AC) joint injuries depends on the degree of injury diagnosed by the Rockwood classification. Inadequate imaging and not selecting the most helpful imaging protocols can often lead to incorrect diagnosis of the injury. A consensus on a diagnostic imaging protocol for acute AC joint injuries does not currently exist. Therefore we conducted a systematic review of the literature considering three diagnostic parameters for patients with acromioclavicular (AC) joint injuries: 1) Assessment of vertical instability; 2) Assessment of horizontal instability; 3) Benefit of weighted panoramic views. Methods Internet databases were searched in March 2016 using the terms (“AC joint” OR “acromioclavicular joint”) AND (MRI OR MR OR radiograph OR X-ray OR Xray OR ultrasound OR “computer tomography” OR “computed tomography” OR CT). Diagnostic, prospective, retrospective, cohort and cross- sectional studies were included to compare their use of different radiological methods. Case reports, cadaveric studies, and studies concerning chronic AC injuries and clinical outcomes were excluded. Results This search returned 1359 citations of which 1151 were excluded based on title, 116 based on abstract and 75 based on manuscript. 17 studies were included for review and were analyzed for their contributions to the three parameters of interest mentioned above. The inter- and intra-observer reliability for diagnosing vertical instabilities of the clavicle using x-ray alone show a high level of reproducibility while for horizontal instabilities the values were much more variable. In general, digitally measured parameters seem to be more precise and reliable between investigators than visual classification alone. Currently, evidence for the value of weighted views and other additional diagnostic imaging to supplement standard x-rays is controversial. Conclusion To date there is no consensus on a gold standard for diagnostic measures needed to classify acute AC joint injuries. The inter- and intra-observer reliability for diagnosing vertical instabilities of the clavicle using bilateral projections show a high level of reproducibility while for horizontal instabilities the results are much more inconsistent. There is currently no clear consensus on a protocol for image-based diagnosis and classification of acute AC joint injuries, leading to a lack of confidence in reproducibility and reliability.
Osseous valgus alignment and posteromedial ligament complex deficiency lead to increased ACL graft forces
Purpose To biomechanically investigate the influence of osseous valgus alignment, with and without deficiency of the posteromedial ligament complex (PMC), on ACL-graft forces under axial load. Methods ACL reconstruction was performed on ten cadaveric knee joints. A lateral distal femur osteotomy was then done to adjust for three different alignment conditions according to the position, where the axial weight bearing line (WBL) dissected the tibial plateau (% from medial to lateral): 50%, 85% and 115%. Each alignment was tested with the PMC intact, deficient and reconstructed. Axial loads of 400 N were applied in 15° of knee flexion and changes of ACL-graft forces and dynamic valgus angle (DVA) were recorded. Results In the PMC intact state, lateralization of the WBL to 85% and to 115% led to significantly increased ACL graft forces (85%: p  = 0.010; 115%: p  < 0.001) and DVAs (85%: p  = 0.027; 115%: p  = 0.027). Dissection of the PMC led to a significant increase of ACL graft forces and DVAs at 85% and 115% valgus alignment ( p  < 0.001) only. In comparison to valgus aligned knees with additional PMC deficiency, ligament reconstruction alone was able to significantly decrease ACL graft forces ( p  < 0.001) and DVAs ( p  < 0.001). However, alignment correction alone was significantly more effective in reducing ACL graft forces ( p  < 0.001) and DVAs ( p  = 0.010). Conclusion Osseous valgus alignment led to significantly increased forces on ACL grafts under axial joint compression, which was even further enhanced, when the PMC was deficient. In the valgus aligned and PMC deficient knee, correction to a straight leg axis was significantly more effective in decreasing forces on the ACL graft than reconstruction of the PMC. In patients with valgus alignment and combined injuries of the ACL and PMC, a correction osteotomy to a straight leg axis as well as reconstruction of the PMC should be considered to protect the reconstructed ACL.
Repair of the medial patellofemoral ligament with suture tape augmentation leads to similar primary contact pressures and joint kinematics like reconstruction with a tendon graft: a biomechanical comparison
Purpose To compare suture tape-augmented MPFL repair with allograft MPFL reconstruction using patellofemoral contact pressure and joint kinematics to assess the risk of patellofemoral over-constrainment at point zero. Methods A total of ten fresh frozen cadaveric knee specimens were tested in four different conditions of the MPFL: (1) native, (2) cut, (3) reconstructed with tendon graft, and (4) augmented with suture tape. The patellofemoral mean pressure (MP), peak pressure (PP) and contact area (CA) were measured independently for the medial and lateral compartments using pressure-sensitive films. Patellar tilt (PT) and shift (PS) were measured using an optical 3D motion tracking system. Measurements were recorded at 0°, 10°, 20°, 30°, 60° and 90° of flexion. Both the tendon graft and the internal brace were preloaded with 2 N, 5 N, and 10 N. Results There was no significant differences found between surgical methods for medial MP, medial PP, medial CA, lateral MP and PS at any preload or flexion angle. Significant differences were seen for lateral PP at 20° knee flexion and 10 N preload (suture tape vs. reconstruction: 1045.9 ± 168.7 kPa vs. 1003.0 ± 151.9 kPa; p  = 0.016), for lateral CA at 10° knee flexion and 10 N preload (101.4 ± 39.5 mm 2 vs. 108.7 ± 36.6 mm 2 ; p  = 0.040), for PT at 10° knee flexion and 2 N preload (− 1.9 ± 2.5° vs. − 2.5 ± 2.3°; p  = 0.033) and for PT at 0° knee flexion and 10 N preload (− 0.8 ± 2.5° vs. − 1.8 ± 3.1°; p  = 0.040). A preload of 2 N on the suture tape was the closest in restoring the native joint kinematics. Conclusions Suture tape augmentation of the MPFL resulted in similar primary contact pressures and joint kinematics in comparison with MPFL reconstruction using a tendon graft. A pretension of 2 N was found to restore the knee joint closest to normal patellofemoral kinematics.