Biomechanical Comparison Between Double-Row Repair and Soft Tissue Tenodesis for Treatment of Proximal Rectus Femoris Avulsions.

Background: Some patients with proximal rectus femoris (PRF) avulsions require surgical treatment after failed nonoperative treatment. There is no consensus on the superiority of suture anchor repair with the suture-bridge repair (SBR) technique versus tenodesis repair (TR) for PRF avulsions. Purpose: To compare the failure load and elongation at failure between SBR and TR and to compare the stiffness of these 2 repair techniques versus the native state. Study Design: Controlled laboratory study. Methods: Seven pairs of human cadaveric hemipelvises were dissected to the PRF and sartorius origins. Each specimen underwent preconditioning followed by a distraction test to determine the stiffness of the native specimen. One specimen of each pair received one of the repair methods (SBR or TR), while the other specimen in the pair received the other repair technique. After repair, each specimen underwent preconditioning followed by a pull to failure. The failure load, elongation at failure, stiffness, mode of failure, and stiffness as a percentage of the native state were determined for each repair. Results: The SBR group exhibited a stronger failure load (223 ± 51 N vs 153 ± 32 N for the TR group; P = .0116) and significantly higher stiffness as a percentage from the native state (70.4% ± 19% vs 33.8% ± 15.5% for the TR group; P = .0085). While the stiffness of the repair state in the SBR group (41.5 ± 9.4 N/mm) was not significantly different from that of the native state (66.2 ± 36 N/mm), the stiffness of the repair state in the TR group (20.3 ± 7.5 N/mm) was significantly lower compared with that of the native state (65.4 ± 22.1 N/mm; P < .001) and repair state in the SBR group (41.5 ± 9.4 N/mm; P = .02). The SBR group primarily failed at the repair site (71%), and the TR group primarily failed at the suture-sartorius interface (43%) and at the muscle (29%). Conclusion: SBR and TR specimens were significantly weaker than the native tendon. The stiffness of the SBR was equivalent to that of the native tendon, while TR was significantly less stiff than the native tendon. The SBR was superior to TR in terms of failure load, stiffness, and percentage stiffness from the native state. Clinical Relevance: SBR may be a better surgical option than TR to optimize failure load and stiffness for PRF avulsions.

Biomechanical Comparison of Proximal Hamstring Reconstruction Using Distal Hamstring Graft Versus Fascia Lata Graft for Treatment of Chronic Hamstring Injury.

BACKGROUND: Surgical reconstruction using autografts is often required in treating chronic proximal hamstring injuries where the hamstring has retracted >5 cm. There is a paucity of evidence that evaluates reconstructive procedures using the 2 most popular autografts, distal hamstring and fascia lata. PURPOSE: To (1) compare failure load and elongation at failure between the proximal hamstring tendon reconstruction with distal hamstring and fascia lata grafts and (2) compare the stiffness between these reconstructions and the native state. STUDY DESIGN: Controlled laboratory study. METHODS: Seven pairs of human cadaveric hemipelvises (mean age, 60.4 ± 5.0 years; 6 male, 1 female) with no evidence of previous injury or abnormality were dissected to the proximal hamstring origin. Through use of a dynamic tensile testing system, each specimen underwent preconditioning followed by a distraction test to determine the native specimen stiffness. Each pair of specimens was assigned to undergo proximal hamstring reconstruction with distal hamstring and reconstruction with fascia lata. Each specimen then underwent preconditioning followed by pull to failure. The failure load, elongation at failure, mode of failure, and stiffness were determined for each repair. RESULTS: The distal hamstring group exhibited a greater failure load (mean, 334 ± 108 N; P = .031) and higher stiffness (mean, 47.6 ± 16.0 N/mm; P = .009) compared with the fascia lata group (mean, 179 ± 78 N and 23.0 ± 11.2 N/mm, respectively). Although the stiffness of the repair state in the distal hamstring group (mean, 61.4 ± 13.4 N/mm) was not significantly different from that of the native state (mean, 47.6 ± 16.0 N/mm), the stiffness of the repair state in the fascia lata group (mean, 23.0 ± 11.2 N/mm) was significantly lower than that of the native state (mean, 60.1 ± 17.7 N/mm) (P < .0001). The elongation at failure of the distal hamstring graft group (mean, 33.0 ± 6.6 mm) was not significantly different from that of the fascia lata graft group (mean, 29.2 ± 14.9 mm) (P = .58). The most common modes of failure for the distal hamstring group (29% each) were at the repair site, at the graft-muscle interface, and at the muscle, while the most common modes of failure for the fascia lata graft were at the tendon-graft interface. CONCLUSION: The distal hamstring group achieved higher failure load and stiffness than the fascia lata group, and stiffness of the distal hamstring group was not significantly different from that of the native tendon. Elongation at failure was not different between repair techniques. Although distal hamstring graft failure predominantly occurred in 3 distinct locations, failure of the fascia lata repair occurred predominantly at the tendon-graft interface. These cadaveric results suggest that it may be more clinically appropriate to use distal hamstring versus fascia lata for proximal hamstring reconstruction. CLINICAL RELEVANCE: Our time-zero study suggests that the proximal hamstring reconstruction with distal hamstring could be the preferred surgical treatment for chronic hamstring injury over reconstruction with fascia lata. The failure load of reconstruction with distal hamstring was inferior to that of primary suture anchor, suggesting that rehabilitation after reconstruction should not be more aggressive than the standard postoperative rehabilitation protocol for acute repair.

Surface repair of the femoral head using press-osteochondral autograft transfer.

Aims: Hyaline cartilage has a low capacity for regeneration. Untreated osteochondral lesions of the femoral head can lead to progressive and symptomatic osteoarthritis of the hip. The purpose of this study is to analyze the clinical and radiological long-term outcome of patients treated with osteochondral autograft transfer. To our knowledge, this study represents a series of osteochondral autograft transfer of the hip with the longest follow-up. Methods: We retrospectively evaluated 11 hips in 11 patients who underwent osteochondral autograft transfer in our institution between 1996 and 2012. The mean age at the time of surgery was 28.6 years (8 to 45). Outcome measurement included standardized scores and conventional radiographs. Kaplan-Meier survival curve was used to determine the failure of the procedures, with conversion to total hip arthroplasty (THA) defined as the endpoint. Results: The mean follow-up of patients treated with osteochondral autograft transfer was 18.5 years (9.3 to 24.7). Six patients developed osteoarthritis and had a THA at a mean of 10.3 years (1.1 to 17.3). The cumulative survivorship of the native hips was 91% (95% confidence interval (CI) 74 to 100) at five years, 62% (95% CI 33 to 92) at ten years, and 37% (95% CI 6 to 70) at 20 years. Conclusion: This is the first study analyzing the long-term results of osteochondral autograft transfer of the femoral head. Although most patients underwent conversion to THA in the long term, over half of them survived more than ten years. Osteochondral autograft transfer could be a time-saving procedure for young patients with devastating hip conditions who have virtually no other surgical options. A larger series or a similar matched cohort would be necessary to confirm these results which, in view of the heterogeneity of our series, seems difficult to achieve.

Avascular femoral head necrosis in young gymnasts: a pursuit of aetiology and management.

AIMS: Avascular femoral head necrosis in the context of gymnastics is a rare but serious complication, appearing similar to Perthes' disease but occurring later during adolescence. Based on 3D CT animations, we propose repetitive impact between the main supplying vessels on the posterolateral femoral neck and the posterior acetabular wall in hyperextension and external rotation as a possible cause of direct vascular damage, and subsequent femoral head necrosis in three adolescent female gymnasts we are reporting on. METHODS: Outcome of hip-preserving head reduction osteotomy combined with periacetabular osteotomy was good in one and moderate in the other up to three years after surgery; based on the pronounced hip destruction, the third received initially a total hip arthroplasty. RESULTS: The described pathology is quite devastating, and extensive joint preserving surgery (which has been shown successful in Perthes' cases) was less successful in this patient cohort. CONCLUSION: Supraselective angiography may be helpful to improve pathomechanical understanding and surgical decision making.Cite this article: Bone Jt Open 2022;3(9):666-673.

Lower 1-Year Postoperative Mortality After Acetabular Versus Proximal Femoral Fractures in Elderly Patients.

BACKGROUND: Geriatric acetabular fractures are becoming more common due to demographic changes. Compared with proximal femoral fractures, surgical treatment is more complex and often does not allow full-weight-bearing. The aims of this study were to compare operatively treated acetabular and proximal femoral fractures with regard to (1) cumulative 1-year mortality, (2) perioperative complications, and (3) predictive factors associated with a higher 1-year mortality. METHODS: This institutional review board-approved comparative study included 486 consecutive surgically treated elderly patients (136 acetabular and 350 proximal femoral fractures). After matching, 2 comparable groups of 129 acetabular and 129 proximal femoral fractures were analyzed. Cumulative 1-year mortality was evaluated through Kaplan-Meier survivorship analysis, and perioperative complications were documented and graded. After confirming that the proportionality assumption was met, Cox proportional hazard modeling was conducted to identify factors associated with increased 1-year mortality. RESULTS: The acetabular fracture group had a significantly lower cumulative 1-year mortality before matching (18% compared with 33% for proximal femoral fractures, log-rank p = 0.001) and after matching (18% compared with 36%, log-rank p = 0.005). Nevertheless, it had a significantly higher overall perioperative complication rate (68% compared with 48%, p < 0.001). In our multivariable Cox regression analysis, older age, perioperative blood loss of >1 L, and wheelchair mobilization were associated with lower survival rates after acetabular fracture surgery. Older age and a higher 5-item modified frailty index were associated with a higher 1-year mortality rate after proximal femoral fractures, whereas postoperative full weight-bearing was protective. CONCLUSIONS: Despite the complexity of operative treatment and a higher complication rate after acetabular fractures in the elderly, the 1-year mortality rate is lower than that after operative treatment of proximal femoral fractures, even after adjustment for comorbidities. LEVEL OF EVIDENCE: Therapeutic Level III. See Instructions for Authors for a complete description of levels of evidence.

The New Bern Chondrolabral Classification Is Reliable and Reproducible.

BACKGROUND: Several classification systems have been used to describe early lesions of hip cartilage and the acetabular labrum in young adults with hip pain. Some of them were introduced before the concept of femoroacetabular impingement was proposed. Others were developed for other joints (such as the patellofemoral joint). However, these often demonstrate inadequate reliability, and they do not characterize all possible lesions. Therefore, we developed a novel classification system. QUESTION/PURPOSE: We asked: What is the (1) intraobserver reliability, (2) interobserver reproducibility, and (3) percentage of nonclassifiable lesions of the new classification system for damage to the hip cartilage and labrum compared with six established classification systems for chondral lesions (Beck et al. [4], Konan et al. [10], Outerbridge et al. [14]) and labral lesions (Beck et al. [3], Lage et al. [12], Peters and Erickson [15])? METHODS: We performed a validation study of a new classification system of early chondrolabral degeneration lesions based on intraoperative video documentation taken during surgical hip dislocations for joint-preserving surgery in 57 hips (56 patients) performed by one surgeon with standard video documentation of intraarticular lesions. The exclusion criteria were low-quality videos, inadequate exposure angles, traumatic lesions, and incomplete radiographic documentation. This left 42 hips (41 patients) for the blinded and randomized analysis of six raters, including those with cam-pincer-type femoroacetabular impingement (FAI) (19 hips in 18 patients), isolated cam-type FAI (10 hips), extraarticular FAI due to femoral anteversion (seven hips), isolated pincer-type FAI (two hips), focal avascular necrosis (two hips), localized pigmented villonodular synovitis (one hip), and acetabular dysplasia as a sequelae of Perthes disease (one hip). The raters had various degrees of experience in hip surgery: Three were board-certified orthopaedic fellows and three were orthopaedic residents, in whom we chose to prove the general usability of the classification systems in less experienced readers. Every rater was given the original publication of all existing classification systems and a visual guide of the new Bern classification system. Every rater classified the lesions according the existing classifications (cartilage: Beck et al. [4], Konan et al. [10], and Outerbridge et al. [14]; labrum: Beck et al. [3], Peters and Erickson [15], and Lage et al. [12]) and our new Bern chondrolabral classification system. The intraclass correlation coefficient with 95% confidence interval was used to assess the intraobserver reliability and interobserver reproducibility. The percentage of nonclassifiable lesions was calculated as an absolute number and percentage. RESULTS: The intraobserver intercorrelation coefficients (ICCs) for cartilage lesions were as follows: the Bern classification system (0.68 [95% CI 0.61 to 0.70]), Beck (0.44 [95% CI 0.34 to 0.54]), Konan (0.39 [95% CI 0.29 to 0.49]), and the Outerbridge classification (0.57 [95% CI 0.48 to 0.65]). For labral lesions, the ICCs were as follows: the Bern classification (0.70 [95% CI 0.63 to 0.76]), Peters (0.42 [95% CI 0.31 to 0.51]), Lage (0.26 [95% CI 0.15 to 0.38]), and Beck (0.59 [95% CI 0.51 to 0.67]). The interobserver ICCs for cartilage were as follows: the Bern classification system (0.63 [95% CI 0.51 to 0.75), the Outerbridge (0.14 [95% CI 0.04 to 0.28]), Konan (0.58 [95% CI 0.40 to 0.76]), and Beck (0.52 [95% CI 0.39 to 0.66]). For labral lesions, the ICCs were as follows: the Bern classification (0.61 [95% CI 0.49 to 0.74]), Beck (0.31 [95% CI 0.19 to 0.46]), Peters (0.28 [95% CI 0.16 to 0.44]), and Lage (0.20 [95% CI 0.09 to 0.35]). The percentage of nonclassifiable cartilage lesions was 0% for the Bern, 0.04% for Beck, 17% for Konan, and 25% for the Outerbridge classification. The percentage of nonclassifiable labral lesions was 0% for Bern and Beck, 4% for Peters, and 25% for Lage. CONCLUSION: We have observed some shortcomings with currently used classification systems for hip pathology, and the new classification system we developed seems to have improved the intraobserver reliability compared with the Beck and Konan classifications in cartilage lesions and with the Peters and Lage classifications in labral lesions. The interrater reproducibility of the Bern classification seems to have improved in cartilage lesions compared with the Outerbridge classification and in labral lesions compared with the Beck, Peters, and Lage classifications. The Bern classification identified all present cartilage and labral lesions. It provides a solid clinical basis for accurate descriptions of early degenerative hip lesions independent of etiology, and it is reproducible enough to use in the reporting of clinical research. Further studies need to replicate our findings in the hands of nondevelopers and should focus on the prognostic value of this classification and its utility in guiding surgical indications. LEVEL OF EVIDENCE: Level II, diagnostic study.

The Acetabular Wall Index Is Associated with Long-term Conversion to THA after PAO.

BACKGROUND: Periacetabular osteotomy (PAO) has been shown to be a valuable option for delaying the onset of osteoarthritis in patients with hip dysplasia. Published studies at 30 years of follow-up found that postoperative anterior overcoverage and posterior undercoverage were associated with early conversion to THA. The anterior and posterior wall indices are practical tools for assessing AP coverage on standard AP radiographs of the pelvis pre-, intra-, and postoperatively. However, no study that we know of has evaluated the relationship between the postoperative anterior and posterior wall indices and survivorship free from arthroplasty. QUESTIONS/PURPOSES: In a study including patients after PAO for developmental dysplasia of the hip (DDH), we evaluated whether the acetabular wall index is associated with conversion to THA in the long-term after PAO. We asked: (1) Is an abnormal postoperative anterior wall index associated with conversion to THA after PAO? (2) Is an abnormal postoperative posterior wall index associated with conversion to THA after PAO? (3) Are there other factors associated with joint replacement after PAO? METHODS: This retrospective study involved pooling data of PAO for DDH from two previously published sources. The first series (1984-1987) comprised the very first 75 PAOs for symptomatic DDH performed at the inventor's institution. The second (1997-2000) comprised a series of PAOs for symptomatic DDH completed at the same institution 10 years later. No patient was lost to follow-up. Fifty hips (44 patients) were excluded for predefined reasons (previous surgery, substantial femoral pathomorphologies, poor-quality radiographs), leaving 115 hips (102 patients, mean age 29 ± 11 years, 28% male) for analysis with a mean follow-up of 22 ± 6 years. One observer not involved in patient treatment digitally measured the anterior and posterior wall indices on postoperative AP pelvic radiographs of all patients. All patients were contacted by mail or telephone to confirm any conversion to THA and the timing of that procedure relative to the index procedure. We performed univariate and multivariate Cox regression analyses using conversion to THA as our endpoint to determine whether the anterior and posterior wall indices are associated with prosthetic replacement in the long-term after PAO. Thirty-one percent (36 of 115) of hips were converted to THA within a mean of 15 ± 7 years until failure. The mean follow-up duration of the remaining patients was 22 ± 6 years. RESULTS: A deficient anterior wall index was associated with conversion THA in the long-term after PAO (adjusted hazard ratio 10 [95% CI 3.6 to 27.9]; p < 0.001). Although observed in the univariate analysis, we could not find a multivariate association between the posterior wall index and a higher conversion rate to THA. Grade 0 Tönnis osteoarthritis was associated with joint preservation (adjusted HR 0.2 [95% CI 0.07 to 0.47]; p = 0.005). Tönnis osteoarthritis Grades 2 and 3 were associated with conversion to THA (adjusted HR 2.3 [95% CI 0.9 to 5.7]; p = 0.08). CONCLUSION: A deficient anterior wall index is associated with a decreased survivorship of the native hip in the long-term after PAO. Intraoperatively, in addition to following established radiographical guidelines, the acetabular wall indices should be measured systematically to ascertain optimal acetabular fragment version to increase the likelihood of reconstructive survival after PAO for DDH. LEVEL OF EVIDENCE: Level III, therapeutic study.

Does the Rule of Thirds Adequately Detect Deficient and Excessive Acetabular Coverage?

BACKGROUND: Assessment of AP acetabular coverage is crucial for choosing the right surgery indication and for obtaining a good outcome after hip-preserving surgery. The quantification of anterior and posterior coverage is challenging and requires either other conventional projections, CT, MRI, or special measurement software, which is cumbersome, not widely available and implies additional radiation. We introduce the "rule of thirds" as a promising alternative to provide a more applicable and easy method to detect an excessive or deficient AP coverage. This method attributes the intersection point of the anterior (posterior) wall to thirds of the femoral head radius (diameter), the medial third suggesting deficient and the lateral third excessive coverage. QUESTION/PURPOSE: What is the validity (area under the curve [AUC], sensitivity, specificity, positive/negative likelihood ratios [LR(+)/LR(-)], positive/negative predictive values [PPV, NPV]) for the rule of thirds to detect (1) excessive and (2) deficient anterior and posterior coverages compared with previously established radiographic values of under-/overcoverage using Hip2Norm as the gold standard? METHODS: We retrospectively evaluated all consecutive patients between 2003 and 2015 from our institutional database who were referred to our hospital for hip pain and were potentially eligible for joint-preserving hip surgery. We divided the study group into six specific subgroups based on the respective acetabular pathomorphology to cover the entire range of anterior and posterior femoral coverage (dysplasia, overcoverage, severe overcoverage, excessive acetabular anteversion, acetabular retroversion, total acetabular retroversion). From this patient cohort, 161 hips were randomly selected for analysis. Anterior and posterior coverage was determined with Hip2Norm, a validated computer software program for evaluating acetabular morphology. The anterior and posterior wall indices were measured on standardized AP pelvis radiographs, and the rule of thirds was applied by one observer. RESULTS: The detection of excessive anterior and posterior acetabular wall using the rule of thirds revealed an AUC of 0.945 and 0.933, respectively. Also the detection of a deficient anterior and posterior acetabular wall by applying the rule of thirds revealed an AUC of 0.962 and 0.876, respectively. For both excessive and deficient anterior and posterior acetabular coverage, we found high specificities and PPVs but low sensitivities and NPVs. CONCLUSION: We found a high probability for an excessive (deficient) acetabular wall when this intersection point lies in the lateral (medial) third, which would qualify for surgical correction. On the other hand, if this point is not in the lateral (medial) third, an excessive (deficient) acetabular wall cannot be categorically excluded. Thus, the rule of thirds is very specific but not as sensitive as we had expected. LEVEL OF EVIDENCE: Level II, diagnostic study.