Recovery in Hip Range of Motion in Young Flexibility Athletes 1 Year After Periacetabular Osteotomy.

Background: Periacetabular Osteotomy (PAO) is a well-established surgical intervention for the treatment of hip dysplasia. Purpose: Our primary objective was to assess whether a group of young flexibility athletes who underwent PAO for hip dysplasia recovered their pre-operative hip range of motion (ROM) within 1 year of surgery. Our secondary objective was to compare hip ROM recovery between a group of young flexibility athletes and a group of non-flexibility athletes who underwent PAO for hip dysplasia. Results: In our study, 100% of flexibility athletes regained preoperative hip external rotation at 1-year post-operation. This was also the first plane of motion to return to preoperative motion in flexibility athletes. A significantly higher percentage of non-flexibility athletes regained their preoperative hip internal rotation compared to flexibility athletes (100% compared to 54%; P = .02), but not flexion or external rotation at 1-year post-operation. Conclusion: Our findings may help providers to set expectations regarding the recovery of hip ROM in flexibility athletes who undergo PAO for hip dysplasia.Level of Evidence: Level IV.

Comparison of 2D, 3D, and radially reformatted MR images in the detection of labral tears and acetabular cartilage injury in young patients.

OBJECTIVE: The purpose of this study was to compare the utility of two-dimensional high-resolution (2D), 3-dimensional with multiplanar reconstruction (3D MPR), and radially reformatted (RR) MRIs when evaluating the complexities of the hip joint in patients with femoroacetabular impingement (FAI). We hypothesized RR would be superior in detecting labral pathology and 2D would be superior in detecting transition zone and acetabular cartilage injury. MATERIALS AND METHODS: 2D, 3D MPR, and RR MRIs of 33 patients, who later underwent surgical treatment for FAI, were evaluated for sensitivity, specificity, and accuracy. Bland-Altman methods were used to estimate agreement between each method and the gold-standard, arthroscopic visualization of the hip joint, regarding the percentage of the hip joint affected by each injury type. RESULTS: 3D MPR and RR groupings were associated with the highest sensitivity and accuracy for labral injury. 3D MPR demonstrated the smallest bias in assessing the percentage of joint affected by labral injury and was the most accurate in identifying acetabular cartilage injury, whereas RR had the smallest mean difference in assessing the percentage of joint affected by acetabular cartilage injury. 2D was the most accurate in identifying transition zone injuries, while RR was superior in assessing the percentage of the joint affected by transition zone injury. CONCLUSIONS: Our results suggest that including both 3D MPR and RR MRI groupings is favorable for accurate joint visualization and well-informed treatment planning, especially given that labral injury is a main source of pain and dysfunction for FAI patients.

The acetabulum in healed Legg-Calvé-Perthes disease is cranially retroverted and associated with global reduction of femoral head coverage: a matched-cohort study.

To evaluate the acetabular morphology in healed Legg-Calvé-Perthes disease after skeletal maturity using computed tomography (CT) scan and to compare with matched controls. We identified 33 (37 hips) patients with healed Legg-Calvé-Perthes disease and closed triradiate cartilage who underwent pelvic CT scan. Each patient was matched based on sex, age and side to a subject with no history of hip disease who had undergone pelvic CT evaluation because of abdominal pain. Both cohorts had 23 (70%) males and mean age of 16.4-16.5 ± 3.6 years. Two independent readers assessed lateral center-edge angle (LCEA), acetabular inclination angle (IA), acetabular depth-width ratio (ADR), acetabular version 10 mm below the dome (cranial) and at the acetabular center and anterior (AASA) and posterior acetabular sector angles (PASA). All measurements had good to excellent interobserver agreement (intraclass coefficients ≥ 0.87). The hips in the Legg-Calvé-Perthes disease cohort had a smaller mean ± standard deviation (SD) superior, anterior and posterior acetabular coverage as assessed by LCEA (13.2° ± 10.7° versus 28.2° ± 3.4°; P < 0.0001), IA (11.6° ± 6.7° versus 3.5° ± 2.8°; P < 0.0001), AASA (52.4° ± 9.5° versus 59.3° ± 5.0°; P = 0.001) and PASA (79.3° ± 5.9° versus 92.3° ± 5.5°; P < 0.0001) compared with controls. The acetabulum was shallower (ADR 287 ± 45 versus 323 ± 28; P = 0.0002) and the acetabular version was decreased cranially (0.4°±9.2° versus 8.2°±6.8°; P = 0.0002) and at the acetabular center (13.7°±5.1° versus 17.2° ±3.8°; P = 0.004) in Legg-Calvé-Perthes disease hips. After skeletal maturity, hips with healed Legg-Calvé-Perthes disease have shallower and more cranially retroverted acetabula, with globally reduced coverage of the femoral head compared with age-, sex- and side-matched control hips.