2025年05月 保髋进展 JCR Q2

BACKGROUND: Tapered fluted stems are an excellent solution for revision hip arthroplasty following periprosthetic fractures. However, existing implant designs differ in terms of the number of splines, taper angle, and cross-sectional design, and there is a lack of knowledge on the biomechanical effect of these design variations. Therefore, the objective of this study was to compare the primary stability of two representative stem designs and the extent and distribution of stem-bone contact in a periprosthetic fracture model. It was hypothesized that a greater number of splines would lead to greater stability. METHODS: There were six pairs of cadaver femora included and underwent computed tomography imaging for templating. An extended trochanteric osteotomy was created and then reduced using three cerclage cables. Subsequently, one femur in each pair was implanted with 1 of 2 commercial designs of tapered fluted stems. During specimen preparation, the position and orientation of the reamer and the stems were measured by laser scanning, allowing measurement of stem-bone contact. Subsequently, each specimen was subjected to 1,000 cycles of biomechanical loading tests, and stem-bone motion was measured using a motion capture system. RESULTS: The average subsidence of the two stems after loading was 313 ± 138 and 181 ± 113 μm (P > 0.05). The largest micromotion during each loading-unloading cycle was observed in the first cycle for both stems, and it remained constant in the subsequent cycles. There was more anterior stem-bone contact than posterior region in both stems, and the average contact area was comparable (1,546 ± 533 and 1,525 ± 587 mm CONCLUSIONS: Different geometric designs did not lead to significant changes in the extent and distribution of stem-bone contact, and both stems demonstrated similar primary stability under the loads tested in this study.

PURPOSE: Borderline hip dysplasia (BhD) may be associated with insufficient acetabular coverage. Thus, we investigated potential differences in acetabular anatomical measurements derived from computerised tomography (CT) that characterise BhD compared with healthy controls. METHODS: BhD patients (lateral centre edge angle [LCEA] between 18° and 25°) and healthy controls (LCEA between 25° and 40°) underwent anteroposterior pelvic X-ray and CT scans to study the Wiberg and Tönnis angle, the extrusion and Fear indices, notch width and depth, anterior and posterior wall heights, anterior and posterior articular surfaces, articular circumference, the ratio between the anterior articular surface and the articular circumference, the ratio between the posterior articular surface and the articular circumference, and the ratio between the notch width and the articular circumference. Independent two-tailed RESULTS: Twenty-three BhD patients (aged 31.5 ± 8.3 years and LCEA 21.6° ± 4.0°) and thirty-one healthy controls (aged 34.1 ± 8.0 years and LCEA 33.7° ± 5.5°) were included. The CT features most sensitive for detecting BhD were the anterior acetabular surface ( CONCLUSIONS: CT characterisation showed insufficient acetabular coverage in BhD patients along the superior axis (lower Wiberg angle, and increased Tönnis angle and extrusion index), anterior axis (lower anterior acetabular surface and anteroposterior acetabular surface ratio, and increased posterior acetabular ratio), and inferior axis (increased acetabular notch width). These structural alterations suggest that periacetabular osteotomy may address persistent pathological deformation and stress on soft tissues and cartilage-bone structures more effectively. LEVEL OF EVIDENCE: Diagnostic III.

PURPOSE: This study evaluates the effects of hip capsule repair and cam lesion excision on capsular healing by assessing biomechanical strength and histological integrity in an in vivo rabbit model. METHODS: An in vivo rabbit model with 80 rabbits was used, where capsulotomy was performed on the right hip of each subject. The rabbits were assigned into four groups: Group 1 (capsulotomy without repair), Group 2 (capsulotomy with capsule repair), Group 3 (capsulotomy + cam resection without repair), Group 4 (capsulotomy + cam resection + capsule repair). Each group was stratified into 4-week and 8-week follow-up subgroups. Biomechanical testing assessed maximum tensile strength, while histological evaluation included semiquantitative grading of collagen arrangement, inflammatory response, osteogenesis, and angiogenesis. RESULTS: Histological analysis revealed superior healing in the capsule repair + cam resection group (Group 4) compared to the unrepaired capsulotomy group (Group 1) ( CONCLUSION: Our findings indicate that cam resection, particularly when combined with capsule repair, significantly improves biomechanical strength and enhances the healing process of the capsule. These findings offer practical guidance for optimising surgical strategies to enhance patient outcomes and long-term joint function. LEVEL OF EVIDENCE: Level III, experimental therapeutic study (prospective and controlled).

BACKGROUND: Iliopsoas impingement after total hip replacement is an uncommon, but well recognised cause of residual groin pain. The primary aim of this study was to review patient outcomes following arthroscopic iliopsoas release. Secondary outcome was to determine the incidence of postoperative instability and review the literature on this complication. METHODS: A retrospective cohort study of all arthroscopic THR iliopsoas release procedures performed from 2012 until 2022 was undertaken. All patients had completed a minimum of 12 months of conservative treatment and had undergone a preoperative ultrasound-guided diagnostic steroid injection.Postoperatively, patients were classified into 3 categories at their 12-month clinical review: complete relief of symptoms; incomplete relief of symptoms but significant improvement; and no/minimal benefit. Any complications were documented and reviewed. RESULTS: 30 patients were included (31 hips); there were 14 males and 16 females. Mean age was 53.4 (range 34-77) years. 21 patients had a THR, 7 patients had a hip resurfacing, 1 patient had bilateral hip resurfacings and underwent bilateral release, and 1 patient had a revision THR. 2 patients were lost to follow-up, leaving 29 hips for inclusion in the study. Patients underwent arthroscopic release a median of 48 months following primary THR (range 12-180 months). At 12-month follow-up, 13 patients (44.8%) had complete relief of symptoms, 9 patients (31.0%) had incomplete relief of symptoms but significant improvement, and 7 patients (24.1) had no improvement.3 patients (10.3%) had frank anterior dislocation of their THR in the early postoperative period. CONCLUSIONS: The majority of patients with persistent iliopsoas tendinitis following hip arthroplasty had significant improvement in symptoms with arthroscopic iliopsoas release. However, the series highlights the potential for postoperative instability and we would advise caution with regards to excessive capsular resectio