2026年6月 保髋进展 JCR Q2

Osteonecrosis of the femoral head (ONFH) is a progressive disorder characterized by regional trabecular bone deterioration that ultimately results in collapse. While elastic property changes in diseased bones are well documented, the contribution of region-specific viscoelastic behavior and its relationship to multiscale microarchitecture and composition remain insufficiently defined. Eighteen femoral heads (mean age: 40.8 ± 7.1 years; 15 males, 3 females; diagnosis: Ficat Stage III/IV) were retrieved during total hip arthroplasty. Patient-matched trabecular cores were harvested from three distinct zones: necrotic (NCZ), sclerotic (SCZ), and healthy (HZ). Bone quality was evaluated using micro-CT, uniaxial compression, nanoindentation, FTIR, and XRD. Viscoelasticity was characterized via stress relaxation and dynamic mechanical analysis (DMA) tests. The NCZ demonstrated microarchitectural decay (bone volume/total volume reduced by 54.54%, p < 0.001) and lower elastic modulus (reduced by 60.25%, p < 0.001) compared to SCZ. DMA revealed that while the NCZ exhibited the lowest storage modulus (E'), it showed a trend toward greater matrix-dominated stress relaxation (~ 25% increase). Conversely, the SCZ exhibited a 60% increase in E' (p < 0.01) but significantly reduced damping and post-yield energy than NCZ, consistent with a stiff yet brittle phenotype. Stress relaxation correlated strongly with mineral/matrix ratio (r = - 0.71) and collagen maturity (r = - 0.64), with collagen spectral markers significantly predicting microscale mechanical properties. ONFH induces profound viscoelastic and structural heterogeneity. This zonal mismatch between the compliant necrotic core and the stiff, brittle sclerotic rim likely promotes stress concentrations, driving structural instability and subchondral failure.

PURPOSE: Patients with femoroacetabular impingement (FAI) can present with abnormal femoral version(FV). Discrepancies were reported for FV Measurement comparing MRI and CT. We assessed difference of FV measurement on MRI and on matched CT.

METHODS: A retrospective IRB-approved comparative study involving 100 hips of symptomatic FAI patients was performed. All patients(100 hips) had hip pain(mean age 28 ± 10 years) and underwent pelvic CT scan and MRI of the same hip. Routine unilateral, multiplanar MRI of the hip was acquired for chondrolabral lesions. Of them, 52 hips(46 patients) underwent hip MRI with standard T1 images, while 48 hips underwent hip MRI with an additional fast MRI with Dixon based images(bilateral T1 Vibe Dixon based images of pelvis and knee) to measure FV. Two readers independently measured FV(Murphy method) on CT and MRI.

RESULTS: Difference of FV decreased significantly(p < 0.001) between CT and MRI with standard images from 4.9 ± 4.5° for Reader 1(7.3 ± 6.7° for Reader 2) to -0.05 ± 1.5°(r = 0.993, p < 0.001)for Reader 1 (0.73 ± 2.95°, r = 0.975, p < 0.001, for Reader 2) with fast Dixon based images.Difference of FV of CT between two readers was 1.9 ± 3.2°(r = 0.969, p < 0.001) and was not significantly different compared to fast MRI with Dixon based images (1.1 ± 4.4°,r = 0.943, p < 0.001).Number of hips with Difference of FV> 5° between CT and MRI were significantly(p < 0.001) reduced from 35 hips (67%,with standard images) to 2 hips (4%, Dixon based images) for reader 1.

CONCLUSION: We changed our clinical practice and use fast MRI with T1 Dixon-based images for FV measurement. This decreased measurement errors in FV and misdiagnosis of FV and could potentially reduce CT scans.

BACKGROUND: Benign intra-articular soft tissue tumors can mimic septic arthritis of the hip (SAH), posing a significant diagnostic challenge. Timely differentiation between these entities is crucial, as SAH requires urgent intervention to prevent adverse outcomes. The present study aims to (1) examine clinical presentations, imaging findings, laboratory results, and histopathological features associated with benign intra-articular soft tissue tumors mimicking SAH and (2) describe diagnostic challenges encountered in treating these patients.

METHODS: A retrospective review identified 23 patients who underwent arthroscopic irrigation and debridement for suspected SAH at a single institution between 2014-2023. Seven patients with negative cultures and intraoperative diagnoses of intra-articular tumors confirmed by histopathology were included in the primary analysis. Clinical presentations, imaging findings, laboratory results, arthroscopic findings, histopathology results, and follow-up data were analyzed. A comparison with the non-tumor cases (n = 16) was performed as a secondary analysis.

RESULTS: The mean age of the tumor group was 25.0 ± 8.1 years and a female predominance (6/7, 85.7%) was observed. All patients presented with acute hip pain, limited range of motion, and elevated C-reactive protein levels (80.0 ± 38.3 mg/L). Three patients presented with fever and three with leukocytosis. Synovial fluid white blood cell counts exceeded 50,000 cells/μL in five patients. Arthroscopy revealed solid tumors in all cases. Tumor necrosis was observed in all cases and tenosynovial giant cell tumor (TGCT) was confirmed histologically in six cases (6/7, 85.7%). Postoperative MRI in four patients showed no tumor recurrence. Compared to the non-tumor group, patients with tumors were significantly younger (p = .016) and had lower preoperative CRP levels (p = .027).

CONCLUSIONS: Differentiating benign intra-articular tumors from SAH remains difficult, particularly among younger and female patient populations with acute presentations of TGCT which, as observed in the present study, may be explained by histopathologic evidence of tumor pedicle torsion and resultant necrosis. MRI can be valuable in identifying intra-articular lesions given that clinical and laboratory findings are frequently equivocal. The proposed diagnostic algorithm offers a framework for identifying cases where preoperative MRI may be beneficial, though it requires validation in larger studies.

PURPOSE: This study aims to establish critical thresholds for preoperative muscle area and width that predict two-year postoperative outcomes and to explore the correlation between baseline muscle area and two-year postoperative recovery in patients undergoing hip arthroscopy for femoroacetabular impingement syndrome (FAIS).

STUDY DESIGN: Retrospective Cohort Study, Level IV.

METHODS: A cohort of 74 patients treated between March 2021 and March 2022 was analyzed. Preoperative MRI measurements were obtained for the cross-sectional area (CSA) and width of the iliopsoas, gluteus maximus, and gluteus medius/minimus muscles. Two years postoperatively, clinical outcomes including the International Hip Outcome Tool-12 (iHOT-12) and the modified Harris Hip Score (mHHS) were assessed. We evaluated correlations between preoperative muscle areas and postoperative outcomes using Pearson correlation coefficients. Multivariate linear regression models were constructed to identify independent associations between muscle CSA/width and postoperative outcomes. Additionally, receiver operating characteristic (ROC) curve analyses were used to explore potential relationships and thresholds between muscle area and the Patient Acceptable Symptom State (PASS) and the Minimal Clinically Important Difference (MCID).

RESULTS: ROC analyses demonstrated that pre-G-med/min width and CSA predicted several two-year endpoints, with notable performance for iHOT-12-PASS (width AUC 0.68, P = 0.0070; CSA AUC 0.66, P = 0.020) and mHHS-PASS (width AUC 0.85, P = 0.0030; CSA AUC 0.80, P = 0.0090); gluteus maximus (width AUC 0.67, P = 0.012; CSA AUC 0.67, P = 0.013) and iliopsoas (width AUC 0.69, P = 0.0060; CSA AUC 0.72, P = 0.0010) can predict iHOT-12-PASS. Correlation analyses revealed small-to-moderate positive relationships between preoperative gluteus medius/minimus width and CSA with postoperative mHHS and iHOT-12 scores. In multivariate models, Pre-G-med/min CSA remained a significant positive predictor of 2-year mHHS (β = 0.33, P = 0.034), while male sex emerged as a significant positive predictor for 2-year iHOT-12 (β = 0.35, P = 0.030 in the cross-sectional area model and β = 0.28, P = 0.049 in the width model).

CONCLUSION: Preoperative widths and cross-sectional areas of the gluteus medius/minimus, gluteus maximus, and iliopsoas muscles may be associated with, and to a limited extent help predict, the clinical outcomes at two years postoperatively in patients with FAIS.

BACKGROUND: Developmental dysplasia of the hip (DDH) contributes to the progression of hip osteoarthritis (OA), particularly in younger individuals. To delay OA development, joint-preserving procedures such as rotational acetabular osteotomy (RAO) improve hip stability by repositioning the acetabulum. Originally introduced by Ninomiya and Tagawa, RAO involves filling the osteotomy gap with autografts or allografts. Since 2013, our institution has transitioned from autografts to allografts. This study compares postoperative outcomes between these graft materials, as no prior studies have directly examined their efficacy.

METHODS: A retrospective analysis of 59 patients (62 hips) who underwent RAO for DDH between June 2006 and June 2022 was conducted. Patients with advanced OA, prior acetabular osteotomy, or inadequate follow-up were excluded. The cohort included 1 male and 58 female patients (mean age, 40.8 years). Clinical outcomes were assessed using the Japanese Orthopaedic Association (JOA) hip score, while radiographic evaluations included center-edge (CE) angle, Sharp angle, acetabular roof obliquity (ARO), acetabular head index, joint space width, and graft thickness. Bone fusion was assessed using Knight's classification, and statistical comparisons were performed between autograft and allograft groups.

RESULTS: Preoperative JOA hip scores were comparable (autograft: 69 ± 14, allograft: 61.9 ± 15.5). At 1 year, both groups demonstrated significant improvement (autograft: 92.3 ± 6.2, allograft: 90.8 ± 6.0). Radiographic evaluations showed improved CE, Sharp angles, and ARO values in both groups, with no significant intergroup differences. Bone fusion progressed similarly, with trabecular reorientation occurring around 25 months. Joint survival rates were 93% at 15 years (autograft) and 100% at 10 years (allograft).

CONCLUSIONS: RAO with autografts and allografts yielded similar favorable outcomes in early-stage hip OA. Both approaches improved hip function and morphology, with high survival rates. The allograft group maintained greater gluteus medius integrity and showed no OA progression after 10 years, suggesting that allografts are a viable, less invasive option. Further research is necessary to assess long-term outcomes and muscle preservation.

Postless hip distraction technique is a novel traction method for hip arthroscopy developed in recent years. Studies have shown that, compared with the traditional post hip distraction technique, it can effectively solve perineal complications, lower the technical threshold of hip arthroscopy, and improve patients' postoperative satisfaction. The standardization of this technique is expected to promote the advancement and popularization of hip arthroscopy. To this end, this Consensus identified 17 questions of the greatest clinical concern that were selected through systematic literature retrieval and evidence quality evaluation, and in combination with clinical practice, using the Grading of Recommendations Assessment, Development and Evaluation (GRADE) system and the Reporting Items for Practice Guidelines in Healthcare (RIGHT), and 20 evidence-based medical recommendations were finally formulated, aiming to improve the standardization and scientific nature of the postless hip distraction technique and provide a basis for improving the quality of patient-centered medical services.

OBJECTIVE: The arthroscopic management of concomitant ischiofemoral impingement (IFI) and femoroacetabular impingement (FAI) frequently necessitates iliopsoas release; however, concerns regarding potential iatrogenic muscle atrophy and strength deficits remain unresolved. Therefore, the purpose of this study was to evaluate the clinical outcomes, volumetric changes, muscle morphology, and objective isokinetic muscle strength in patients undergoing arthroscopic treatment for concomitant IFI and FAI involving iliopsoas release.

METHODS: This retrospective matched-cohort study analyzed patients treated between January 2019 and January 2020. It included 15 female patients (IFI + FAI group) who underwent arthroscopic IFI decompression and iliopsoas release, and 15 propensity-matched patients (Isolated FAI group) treated for FAI alone. At a minimum 2-year follow-up, patient-reported outcomes (PROs) were assessed. Muscle morphology was evaluated on MRI using 3D volumetric reconstruction for muscle volume, and the Goutallier classification was used to assess fatty infiltration at three standardized anatomical levels. Functional recovery was objectively measured using isokinetic hip flexor and extensor strength testing at 60°/s and 180°/s, comparing the involved hip to the uninvolved contralateral side. Statistical analyses included paired t-tests, Mann-Whitney U tests, and Wilcoxon signed-rank tests.

RESULTS: Both groups demonstrated significant improvements in PROs postoperatively (p < 0.001). Volumetric analysis revealed a significant reduction in iliopsoas muscle volume (25.5% decrease) in the IFI + FAI group postoperatively. Despite this volumetric reduction, postoperative MRI demonstrated preservation of muscle quality, as evidenced by low Goutallier grades (Grade < 1) and no significant difference in fatty infiltration compared to the control group (p > 0.05). Functionally, isokinetic testing demonstrated significant deficits in peak flexion torque compared to the healthy contralateral side (p < 0.001). Notably, while outcomes for activities of daily living were satisfactory, a statistically significant difference was observed in the Substantial Clinical Benefit (SCB) achievement rate regarding sports function between the groups.

CONCLUSION: Iliopsoas release resulted in significant strength deficits, but no significant changes in muscle morphology were observed. However, patient-reported outcomes (PROs) showed improvement, with no significant increase in fatty infiltration, suggesting that functional recovery may occur despite structural deficits.

INTRODUCTION: The iliopsoas muscle passes immediately anterior to the hip joint and lies in close proximity to the acetabular labrum at the level of the psoas valley. This anatomical relationship suggests that local muscle morphology may be associated with symptomatic hip pathology. The present study investigated the association between iliopsoas cross-sectional area at the psoas valley, adjacent osseous morphology, and surgically treated symptomatic hip-pathologies.

METHODS: In this retrospective case-control study, 92 adult patients who underwent hip arthroscopy between 2019 and 2024 and had preoperative computed tomography (CT) imaging were compared with 50 age- and sex-matched controls without documented hip pain who had CT scans obtained for non-hip-related indications. Three-dimensional CT reconstructions were used to measure retroinguinal and psoas-valley morphometric parameters, including iliopsoas crosssectional area at the level of the psoas valley. Multivariable logistic regression adjusted for age and body mass index was performed for variables that differed between groups.

RESULTS: The groups did not differ significantly in age, sex, body mass index, or side. The lacuna musculorum ratio was higher in the surgical cohort than in controls (0.5 ± 0.1 vs. 0.4 ± 0.1; p < 0.001). Iliopsoas cross-sectional area at the psoas valley was smaller in the surgical cohort (12.5 ± 3.2 cm2 vs. 13.7 ± 2.8 cm2; p = 0.025). In multivariable analysis, a higher lacuna musculorum ratio (OR:1.094, 95% CI 1.026-1.167; p = 0.006) and a smaller iliopsoas cross-sectional area (OR:0.998, 95% CI 0.996-1.000; p = 0.039) remained associated with membership in the surgically treated cohort.

CONCLUSION: Smaller iliopsoas cross-sectional area at the psoas valley was more often associated with surgically treated hip pathologies. These findings support a possible anatomical relationship between anterior hip soft-tissue morphology and symptomatic hip pathology, but they do not establish a protective causal effect of greater iliopsoas muscle bulk against labral injury.

INTRODUCTION: The aim of this study is to reach consensus and prioritise the most clinically important assessments, diagnostic classifications, and outcome measures by an international panel of experts for Legg-Calve-Perthes disease.

MATERIALS AND METHODS: A three-round modified e-Delphi survey was conducted between April and May 2025. Participants rated the clinical importance of 14 clinical assessments, 26 radiological assessments, eight diagnostic classifications, and 26 outcome measures identified by a scoping review. Consensus was defined as ≥ 75% agreement. In the final round, items in each category were prioritised for overall condition and by specific age groups (< 6 years, 6-8 years, > 8 years).

RESULTS: Thirty-eight health professionals, from nine countries participated in round 1. Thirty-four completed all three rounds, a retention rate of 89.5%. Consensus and prioritisation for clinical use were achieved for 10 clinical assessments, three radiological assessments, three diagnostic classifications, and three outcome measures.

CONCLUSION: Paediatric specialists have reached consensus and prioritised methods to evaluate and diagnose Legg-Calve-Perthes disease in clinical practice. These results represent an important step towards improving continuity of care and the foundation for future development of clinical practice guidelines.

BACKGROUND AND OBJECTIVE: Developmental dysplasia of the hip (DDH) is a common pediatric condition requiring timely surgical intervention in older children. Conventional Pemberton osteotomy, while effective, carries a risk of iatrogenic injury to the triradiate cartilage due to its blind deep-pericapsular trajectory. The modified Pemberton osteotomy (MPO) shifts the osteotomy endpoint to 3-5 mm above the sciatic notch, creating a greenstick hinge above the Y-shaped cartilage to avoid growth-plate damage. This study aimed to evaluate the mid- to long-term efficacy and safety of MPO in children with DDH over a minimum follow-up of 5 years.

MATERIALS AND METHODS: We retrospectively reviewed 55 patients (71 hips) who underwent open reduction combined with MPO between May 2004 and June 2025. Radiographic parameters included acetabular index (AI), central-edge angle (CEA), and Reimer index (RI). Clinical and radiographic outcomes were assessed using McKay criteria and Severin classification, respectively.

RESULTS: The mean follow-up duration was 7.21±1.64 years. The mean AI improved from 39.66 ± 5.46° preoperatively to 12.71 ± 8.37° at final follow-up, demonstrating powerful and stable acetabular remodeling capacity. According to the McKay clinical criteria, highly satisfactory functional outcomes were achieved, with an excellent-good rate of 88.7% (63/71 hips). Radiographic assessment using the Severin classification confirmed excellent joint congruence, yielding an excellent-good rate of 93.0% (66/71 hips). Avascular necrosis (AVN) occurred in 8 hips (11.2%), which is a low and acceptable incidence compared to historical pelvic osteotomies.

CONCLUSION: MPO provides favorable and durable mid- to long-term clinical and radiographic outcomes for DDH in children. By avoiding iatrogenic injury to the triradiate cartilage, MPO offers improved surgical safety compared with conventional Pemberton osteotomy, with an acceptable AVN rate directly attributable to the procedure.

BACKGROUND: Slipped capital femoral epiphysis (SCFE) is the slippage of the proximal femoral epiphysis on the femoral neck through the epiphyseal plate. This condition is generally observed in male, obese patients during pubertal growth spurts, and it can sometimes be associated with endocrine disorders. Despite its significant incidence in the paediatric population, the diagnosis is frequently delayed which leads to significant worsening of the prognosis. We present a case of SCFE in which the diagnosis was delayed due to a series of confounding factors.

CASE PRESENTATION: We present a case of a 16-year-old boy who came to our rheumatology centre due to persistent limp for several months. Previous investigations aimed to exclude orthopaedic, infectious or inflammatory conditions, apparently revealed nothing significant, so he was referred for a rheumatological evaluation. Upon further investigation, a SCFE was identified and treated surgically with the modified Dunn procedure. Additionally, during the evaluation, endocrinological conditions such as insulin resistance and delayed puberty were discovered.

CONCLUSION: This case shows that, even in the presence of a suggestive medical history and clinical picture, a common diagnosis such as SCFE can be delayed. The delay in this diagnosis is correlated with clinical worsening of the patient and the need for more invasive management. Therefore, SCFE should always be considered in an adolescent boy who starts experiencing a limp or pain in the lower limbs, even if poorly localized, especially because the diagnosis can be quickly made with a pelvic x-ray. Furthermore, it is always important to remember that conditions such as SCFE, can be associated with endocrinological comorbidities.

Hip osteoarthritis (HOA) is the most common hip joint disorder, accounting for approximately 27.9% of all cases of osteoarthritis (OA), often leading to total hip replacement (THR). In the last decades, femoroacetabular impingement (FAI) has been addressed as a significant etiological factor in the development of early-onset HOA, especially in young adults with non-dysplastic hips. FAI has been found to cause damage to all joint tissues, cartilage, labrum, and subchondral bone, thus underlining the importance of an early diagnosis and intervention to prevent progression to end-stage disease. This review aims to provide a comprehensive overview of the biochemical, morphological, and cellular alterations occurring in hip joint tissues in the presence of FAI. Understanding the early pathological changes is of crucial importance as they often precede radiographic signs of disease and may serve as valuable biomarkers for early detection and management of FAI and peri-arthritic conditions to delay or prevent the need for THR in younger populations.

Developmental dysplasia of the hip (DDH) causes preventable morbidity when diagnosis is delayed. We review advances that address screening gaps: 3-dimensional (3D) ultrasound for volumetric visualization with retrospective plane selection; artificial intelligence (AI)-assisted 2-dimensional (2D) cine sweeps that add automated quality control and classification for lightly trained operators; and open-source software and datasets that enable external validation and standardization. A pragmatic pathway is universal newborn screening using brief AI-assisted 2D sweeps, with abnormal or indeterminate results referred for confirmatory 3D ultrasound to define dysplasia patterns and guide care. Implementation studies and consensus standards for acquisition and reporting are priorities.

BACKGROUND: Late diagnosis of developmental hip dysplasia (DDH) may warrant either open or closed reduction of the hip. Proximal femoral growth disturbance (PFGD) is a possible complication following these procedures.

METHODS: A systematic search of PubMed, Embase, Web of Science, The Cochrane Library and OrthoSearch from the date of inception of each database through to the 2 February 2025 was performed. The primary outcome of interest was the prevalence of clinically significant PFGD following open or closed reduction after 6 months of age. This was defined as Kalamchi-MacEwen or Bucholz-Ogden Type 2 or above.

RESULTS: The prevalence of clinically significant PFGD in patients undergoing open reduction was 12.47% (95% Confidence interval (CI): 10.39-14.69), whereas the prevalence of clinically significant PFGD in patients undergoing closed reduction was 9.53% (95% CI: 6.91-12.46). Multivariate analysis suggested that mean age at time of reduction was associated with an increase in the prevalence of PFGD in patients undergoing closed reduction (p = 0.022).

CONCLUSION: We described the prevalence of clinically significant PFGD following closed reduction and open reduction. In both open and closed reduction groups, we observed a high relative heterogeneity (I 2), but acceptable absolute heterogeneity (τ 2), and pooled prevalence estimates should be interpreted with caution. Further studies exploring the influence of disease severity and age on treatment method is required to allow reliable comparisons between open and closed reduction.

PROSPERO REGISTRATION NO: CRD420251015622.

PURPOSE: Perthes disease is a rare self-limiting avascular necrosis of the developing proximal capital femoral epiphysis. Identifying methods used to assess, diagnose and determine outcomes is essential to improve consistency in research and clinical care for this patient population.

METHODS: The Preferred Reporting Items for Systematic Reviews and Meta-Analyses extension for scoping reviews was used. Four electronic databases (Scopus, MEDLINE, CINAHL and Embase) were searched with articles included if clinical and radiological assessments were conducted on more than 10 participants, aged 0 to <18 years with Legg-Calvé-Perthes disease post 2004.

RESULTS: From 9145 records, 32 studies were included, identifying 16 clinical assessments, 23 radiological assessments, 10 diagnostic classifications and 22 outcome measures. Overall, 64% of outcome measures identified are not currently validated for children and adolescents.

CONCLUSIONS: Substantial variability in the methods used to assess, diagnose and determine outcomes in children and adolescents with Perthes disease was identified. When coupled with limited use of validated paediatric measures, this inconsistency complicates clinical decision-making, reduces consistency in patient care and prevents comparability across studies. Establishing expert consensus to determine the most appropriate, accurate and child-specific measures is needed to enhance consistency in patient care, enable more robust outcome reporting and strengthen future research in Perthes disease.

SIGNIFICANCE OF STUDY: Significant variation in diagnostic, assessment and outcome measures for Perthes disease underscores the need for validated, child-specific tools to improve clinical decision-making, facilitate comparability across studies and strengthen future research.

LEVEL OF EVIDENCE: Level III, scoping review.

Paediatric hip pain is a common clinical presentation and can be caused by a wide range of aetiologies, many of which are uniquely related to the growing immature skeletal system such as developmental hip dysplasia, Perthes disease and slipped capital femoral epiphysis. However, atypical or referred causes of hip pain often require a broader diagnostic approach beyond the hip joint itself, and can pose diagnostic challenges for clinicians. This article aims to provide a comprehensive review from an imaging perspective, highlighting common pathologies outside the hip that can also present with similar symptoms, including important pelvic, abdominal, and neoplastic pathologies, which are discussed. By expanding the diagnostic spectrum, we aim to improve the accuracy and timeliness of diagnosis and management in children with atypical causes of hip pain.