2026年5月 保髋进展 JCR Q2

OBJECTIVE: Osteonecrosis of the femoral head (ONFH) is a common disabling hip disorder with an annually increasing incidence due to factors such as corticosteroid administration. Core decompression is an effective surgical intervention for early-stage ONFH, and robot-assisted technology can enhance the accuracy and minimally invasiveness of this procedure. However, its clinical efficacy requires comprehensive evaluation with high-quality evidence. This study aimed to assess the clinical efficacy and safety of robot-assisted core decompression (RACD) in the treatment of ONFH.

METHODS: We systematically searched Chinese and English databases up to December 1, 2025, for case series, cohort studies, and randomized controlled trials (RCTs) on RACD for ONFH. The primary outcome was the femoral head collapse rate; secondary outcomes included the Harris Hip Score (HHS), Visual Analogue Scale (VAS) score, and postoperative complications. Meta-analysis was performed using fixed-effects or random-effects models, with subgroup and sensitivity analyses conducted to verify results.

RESULTS: A total of 12 studies were included (1 RCT, 9 cohort studies, 2 case series), involving 325 patients. Meta-analysis showed that the overall femoral head collapse rate after robot-assisted core decompression was 9% (95% CI: 7%-13%). In the subgroup of ARCO Stage II patients with follow-up > 1 year, the femoral head collapse rate was 12% (95% CI: 8%-17%). The mean postoperative improvement in HHS was 17.38 points (95% CI: 14.40-20.37), and the mean postoperative improvement in VAS score was 2.75 points (95% CI: 2.01-3.50). No complications such as infection or neurovascular injury were reported in any of the studies that reported complications (n = 7, 222 patients in total). Sensitivity analysis indicated that the results were robust. Egger's test suggested potential publication bias for HHS, VAS, and femoral head collapse rate; however, the adjusted effect sizes still supported clinical benefit. Given the high heterogeneity, the adjusted effect sizes should be interpreted with caution.

CONCLUSION: Available evidence supports the effectiveness of robot-assisted core decompression in the treatment of early-stage ONFH. RACD yields functional improvement and pain relief in patients with ONFH, with acceptable short-to-medium-term safety. Current evidence, however, are insufficient to confirm that RACD yields superior hip preservation efficacy compared with MCD. Further direct, high-quality comparative studies are required to determine and quantify the benefits of RACD compared to MCD.

TRIAL REGISTRATION: PROSPERO (CRD420251266114).

BACKGROUND: Hip displacement is a major cause of pain and reduced quality of life in non-ambulatory children with spastic cerebral palsy. Reconstructive hip surgery aims to restore stable femoral head containment, improve comfort, and facilitate daily care. This study evaluated short-term radiographic and caregiver-reported outcomes after reconstructive hip surgery in non-ambulatory children with spastic cerebral palsy, including exploratory subgroup analyses of varus derotational osteotomy (VDRO) alone and VDRO combined with Dega pelvic osteotomy, and the 12-month redislocation rate.

METHODS: This prospective cohort study included 40 non-ambulatory children with spastic cerebral palsy (50 hips; mean age 6.54 ± 1.07 years). Procedure selection was based on preoperative radiographic findings and intraoperative hip stability. Thirteen hips underwent VDRO alone, and 37 hips underwent VDRO combined with Dega pelvic osteotomy for acetabular dysplasia (acetabular index > 25°) or intraoperative posterolateral instability. Primary aim was to measure migration percentage and acetabular index preoperatively and during 12-months follow-up. Secondary aim was to assess 12-month redislocation rate and caregiver-reported quality of life using the Caregiver Priorities and Child Health Index of Life with Disabilities (CPCHILD) questionnaire at baseline and 12 months. Analyses used generalized estimating equation models (GEE) to account for bilateral hips and repeated measures.

RESULTS: In the overall cohort, migration percentage improved from 88.12 to 20.64 and acetabular index from 30.65 to 25.01 at 12 months (both p < 0.001). In exploratory subgroup analyses, 12-month migration percentage decreased from 70.83 to 33.15 after VDRO alone and from 93.94 to 15.99 after VDRO + Dega. Redislocation occurred in 8 of 50 hips (16.0%) overall, including 46.2% after VDRO alone and 5.4% after VDRO + Dega. CPCHILD total scores improved significantly in both groups, with no significant between-group difference in change.

CONCLUSIONS: Reconstructive hip surgery was associated with short-term radiographic improvement and improved caregiver-reported outcomes in this cohort of non-ambulatory children with spastic cerebral palsy. Although 12-month redislocation was lower after VDRO + Dega, the non-randomized design, baseline imbalance, and short follow-up limit comparative inference.

BACKGROUND: The aim of this study was to evaluate clinical and treatment-related factors associated with advanced-stage femoral head avascular necrosis (AVN) (Ficat stage III-IV) in patients who developed osteonecrosis following COVID-19 infection, based on long-term follow-up data.

METHODS: This single-center retrospective cohort study included patients diagnosed with femoral head AVN after confirmed COVID-19 infection who had at least five years of clinical and radiological follow-up. Demographic characteristics, comorbidities, clinical severity of COVID-19, duration of hospitalization, intensive care unit (ICU) requirement, type and duration of systemic corticosteroid therapy, and duration of antiviral treatment were recorded. AVN was staged according to the Ficat and Arlet classification. Patients were divided into early-stage (stage I-II) and advanced-stage (stage III-IV) groups. Independent predictors of advanced-stage AVN were evaluated using logistic regression analysis. Receiver operating characteristic (ROC) analysis was performed to determine the discriminatory ability of antiviral treatment duration for advanced-stage disease. Time to osteonecrosis was defined as the interval between confirmed RT-PCR diagnosis of COVID-19 and first MRI confirmation of femoral head AVN.

RESULTS: A total of 40 patients were included. Advanced-stage AVN was significantly associated with longer hospitalization duration, prolonged corticosteroid use, extended antiviral treatment, and the presence of hypertension. Multivariable logistic regression analysis identified hypertension, hospitalization duration, steroid treatment duration, and antiviral treatment duration as independent risk factors for advanced-stage AVN. ROC analysis demonstrated that an antiviral treatment duration ≥ 9.5 days showed excellent discriminatory performance for advanced-stage AVN (AUC = 0.950). These results reflect associations within a selected cohort of patients with post-COVID AVN and do not imply a direct causal relationship. However, this finding should be interpreted with caution due to the limited sample size and should be considered exploratory rather than definitive.

CONCLUSIONS: In patients who develop femoral head AVN following COVID-19 infection, disease progression appears closely related to the clinical severity of COVID-19 and overall treatment burden. Patients with severe COVID-19 requiring prolonged hospitalization and extended treatment exposure should be carefully monitored for progression to advanced-stage AVN. The identified cut-off value should be considered hypothesis-generating rather than definitive.

PURPOSE: To introduce the delamination width and delamination length for the quantitative description of the delamination between cartilage on MRI, and to determine the diagnostic value for acetabular cartilage delamination (ACD).

METHODS: Data between January 2018 to December 2020 was reviewed. Patients diagnosed femoroacetabular impingement syndrome (FAIS) and underwent hip arthroscopy were included. Exclusion criteria were prior hip surgery and concomitant hip conditions. The delamination width and delamination length were measured at the coronal slice on magnetic resonance imaging (MRI) where the low-signal area on the fat-saturated proton density (FSPD) sequence was most apparent between the cartilage. The delamination width was measured along the direction of the radial line originating from the center of the femoral head. The delamination length was measured as the curve across the endpoints of delamination. The receiver operating characteristic (ROC) curve analysis was performed to evaluate the diagnostic value of these measurements.

RESULTS: A total of 176 patients were included, with 69 (39.2%) patients diagnosed with ACD under arthroscopy. Patients with ACD demonstrated significant larger delamination width and delamination length compared to patients without ACD (all with P < 0.001). The area under curve (AUC) for delamination width and length predicting ACD was 0.8677 (95% CI: 0.8113 to 0.9240) and 0.8113 (95% CI: 0.7528 to 0.8698), respectively. The cut off value of delamination width was 0.95 mm, with the sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV) to be 89.9%, 74.8%, 70.0%, and 91.9%, respectively. The cut off value of delamination length was 2.80 mm, with the sensitivity, specificity, PPV, and NPV to be 43.0%, 94.2%, 90.2%, and 48.4%, respectively. Male sex and BMI were positively associated with delamination width and delamination length (all with P < 0.05).

CONCLUSION: The delamination width and delamination length demonstrated good diagnostic value for ACD. Male sex and BMI were positively associated with these measurements. ACD may occur when the delamination width exceeds 0.95 mm and delamination length exceeds 2.80 mm in patients with FAIS.

LEVEL OF EVIDENCE: Level III. Cohort study.

BACKGROUND: Femoroacetabular impingement syndrome (FAIS) is a movement-related disorder and causing hip and/or groin pain in young active adults. Movement patterns in individuals with FAIS may be modifiable through conservative management. Identifying biomechanical differences between cohorts with asymptomatic cam morphology (FAIM) and FAIS could reveal relevant treatment targets. This study compared lower limb kinematics and kinetics between FAIS, FAIM, and healthy controls during double- (DLS) and single-leg squats (SLS).

METHODS: Whole-body motion and ground reaction forces were synchronously recorded during five DLS and five SLS. Joint angles, moments, and spatiotemporal parameters (mean squat velocity and maximum squat depth) were compared between groups using a one-way repeated measures ANOVA with statistical parametric mapping (SPM).

RESULTS: During DLS, there were no differences in hip or knee kinematics, or hip, knee, or ankle moments. The FAIM group had less ankle dorsiflexion than controls during both descent and ascent (P < .01). During SLS, the FAIM group had greater hip flexion than the FAIS group (P < .01), and the FAIS group had greater external hip rotation than controls (P < .01) and a greater hip abduction moment than the FAIM group (P < .01).

CONCLUSION: The greater demands of SLS may require those with FAIS to perform it differently to those without symptoms, regardless of the presence of cam morphology. Given all groups squatted to a similar depth, hip biomechanics - including flexion, rotation, and abduction moments - may be a more relevant target for rehabilitation.

BACKGROUND: Long-term prospective data on periacetabular osteotomy (PAO) from Middle Eastern populations are limited. This study evaluated ≥ seven year clinical, functional, and radiographic outcomes following PAO and identified predictors of survivorship.

METHODS: Thirty-six consecutive patients (34.6 ± 7.2 years; 78% female) undergoing PAO (2014-2018) were prospectively followed. Inclusion required symptomatic dysplasia with Tönnis 0-2. Outcomes included HHS, WOMAC, HOS, SF-36, radiographic parameters (LCEA, AI), complications, and THA conversion. Reliability, multivariate regression, and Kaplan-Meier analyses were performed.

RESULTS: At 7.8 ± 1.2 years, HHS improved from 63.5 ± 11.2 to 89.6 ± 7.8 (p < 0.001). LCEA increased from 16.2 ± 4.3° to 31.8 ± 3.9° and AI decreased from 22.8 ± 5.1° to 7.2 ± 3.6°. ICC for measurements was 0.92. Complications occurred in 16.7% (mostly minor). THA conversion was 5.6%, both with preoperative Tönnis 2 and correction < 12°. Magnitude of LCEA correction independently predicted HHS improvement (β = 0.41, p < 0.01).

CONCLUSIONS: PAO achieved durable correction and sustained functional improvement with low THA conversion at mid- to long-term follow-up. Preoperative cartilage status and adequacy of correction are key determinants of outcome.

To quantify the three-dimensional shift of the femoral head after periacetabular osteotomy and to identify the relevant morphological factors. This retrospective study included 26 patients (30 hips) who underwent periacetabular osteotomy at a single institution. Pre- and postoperative supine and standing anteroposterior two-dimensional images and pelvic computed tomography scans were obtained. Using three-dimensional-to-two-dimensional model-image registration techniques, we quantified acetabular and femoral head center shifts in both the supine and standing positions along three axes based on the anterior pelvic plane. Correlations between femoral head shift and pre- and postoperative hip morphological parameters on standardized supine radiographs were examined. In the supine position, the femoral head center shifted significantly (5.0 ± 2.3 mm), with medial (-1.5 ± 3.8 mm) and posterior (-1.8 ± 3.5 mm) displacement. Similarly, in standing, the femoral head center shifted significantly (4.8 ± 2.4 mm), with medial (-1.5 ± 3.8 mm) and posterior (-1.4 ± 3.6 mm) displacement. Lower preoperative anterior wall index was correlated with greater medial shift (r = 0.37, p = 0.04) and less posterior shift (r = -0.40, p = 0.03). Periacetabular osteotomy was associated with measurable three-dimensional reorientation of the hip center in both supine and standing positions. Lower preoperative anterior wall index was correlated with greater medial shift and less posterior shift, although the effect sizes were modest. These findings suggest that hip center shift after periacetabular osteotomy is a secondary effect of multiplanar acetabular reorientation and that three-dimensional assessment may provide information beyond conventional two-dimensional evaluation, particularly for anteroposterior changes.

Understanding factors associated with early hip osteoarthritis (OA) in young active adults may facilitate hip OA prevention. We investigated the cross-sectional association between hip contact force (HCF) during walking and cartilage defect severity, accounting for cam morphology size (alpha angle), hip pain severity, sex, age, and walking speed, in football players with hip/groin pain. One hundred and twenty-one football players (18-50 years; 26 women) with > 6-month hip/groin pain and no radiographic OA underwent MRI and a Dunn 45° radiograph. Outcome: Scoring Hip Osteoarthritis with MRI (SHOMRI) score for cartilage defect severity (0-20), categorized into three SHOMRI groups: (a) SHOMRI = 0; (b) SHOMRI = 1-3; and (c) SHOMRI = 4+. Movement and ground force data were captured whilst participants walked at their self-selected pace. Musculoskeletal modeling was used to calculate HCF for one stride cycle. The exposure variable was HCF impulse (body weight times seconds [BW.s]). Differences in HCF impulse based on SHOMRI group (for the most symptomatic hip) were assessed using linear models, controlling for alpha angle, sex, age, walking speed, hip pain, and contralateral hip pain status. Resultant HCF impulse was significantly higher for participants in the 0 versus 4+ SHOMRI group (mean difference; 95%CI: 0.142BW.s; 0.028-0.256 for swing and 0.106BW.s; 0.029-0.184 for stance) and 0 versus 1-3 SHOMRI group (0.071 BW.s; 0.016-0.125 for swing). Participants with more severe cartilage defects walked with lower hip joint loading, and other variables (e.g., alpha angle size, hip pain severity, age) contributed little to this relationship. Hip joint under-loading could be a possible target for hip OA prevention.

BACKGROUND: Osteonecrosis of the femoral head (ONFH) remains a challenging condition in orthopaedics1. Free vascularized fibular grafting (FVFG) theoretically has the potential to restore blood supply to the femoral head and enhance mechanical stability within the femoral head. This method has shown promising clinical outcomes in hip preservation. Previous studies have utilized the anterolateral approach to the hip for this surgical procedure. Here, we report a minimally invasive technique utilizing the direct anterior approach for debridement and bone grafting, requiring a shorter fibular graft and simplifying the procedure. This method holds potential as an effective treatment option for early to mid-stage femoral head necrosis2.

DESCRIPTION: This technique integrates the procurement of the fibula and its implantation into the femoral head via a direct anterior approach. The fibular pedicle is harvested, along with its nutrient peroneal vessels. The lateral circumflex femoral vessels are then exposed. Subsequently, an anterior capsulotomy and a cortical trough are created along the femoral neck. The necrotic region is extirpated and substituted with the fibular pedicle and cancellous bone from the femoral neck. Finally, an anastomosis is formed between the peroneal vessels of the transplanted fibula and the ascending branches of the lateral circumflex femoral vessels3.

ALTERNATIVES: Nonoperative alternatives for the treatment of ONFH include lifestyle changes like weight control, restriction of weight-bearing activities, and alcohol cessation, alongside pharmaceutical interventions that include antilipemic agents, anticoagulants, vasodilators, and bisphosphonates. Physical therapy methods such as electromagnetic stimulation, extracorporeal shock-wave therapy, and hyperbaric oxygen may also be employed. The surgical approaches to this condition cover a wide array of operations, including core decompression, precursor cell implantation, nonstructural bone grafting, nonvascularized bone grafting, vascularized iliac bone flap transfer, transtrochanteric rotational osteotomy, and porous metal implantation4.

RATIONALE: FVFG theoretically not only provides potential mechanical support for the necrotic femoral head, which may help prevent collapse, but also has the potential to improve the internal circulation of the femoral head and thus provide a favorable environment for osteoblast activity and contribute to bone induction and formation5. It is hypothesized that FVFG targets the pathological mechanism of femoral head necrosis to potentially impede disease progression. For patients <50 years old, FVFG is suitable for treating Association Research Circulation Osseous (ARCO) stage-II ONFH before collapse. For patients <30 years old, FVFG can be utilized to protect the femoral head, even if it has collapsed as ARCO stage III6. In light of the need to obtain the vascularized fibular graft, potential complications may include abnormal skin sensation in the lower leg, leg weakness, and ankle pain or weakness3.

EXPECTED OUTCOMES: On the basis of existing research4, FVFG is regarded as a therapeutic option for ONFH. Some reports have provided evidence that FVFG is more effective than nonoperative treatment or core decompression without grafting-although a direct comparison with core decompression augmented with cellular therapies in a prospective trial is lacking5,7-9. FVFG also carries the benefit of improving blood supply to the femoral head5. In our prior investigation published in 20133, we presented the comprehensive outcomes of FVFG as a treatment strategy for ONFH. The follow-up ranged from 3 to 10 years, with an average of 5.0 years. Only 4.0% of patients (20 of 407) subsequently underwent total hip arthroplasty (THA). On average, patient Harris hip scores increased from 65.0 to 86.9. In another study of 854 patients (1,206 hips) published in 202410, 275 hips (22.8%) had hip failure at a median follow-up of 110.3 months (interquartile range [IQR], 29.3 to 137.8 months; range, 3 to 214 months). Of these, 143 hips underwent THA and an additional 132 hips were considered to require a future THA. The median time to hip failure was 68.2 months (IQR, 14.9 to 120.4 months) after FVFG. Kaplan-Meier survival analysis showed that, overall, the estimated survival time was 165.5 months, estimated cumulative survival rate was 79.2% (95% confidence interval [CI], 77.1% to 81.3%), and estimated annual hazard rate was 1.9% (95% CI, 1.7% to 2.1%). Among 1,161 hips with complete records, mean Harris hip scores improved from 70.1 ± 16.4 points before FVFG to 80.9 ± 14.0 points at the time of the latest follow-up (p < 0.001). When compared with other surgical techniques, FVFG exhibits distinct benefits because of its periosteal blood supply and strong structural support, although comparisons with cellular therapies have not been performed8.

IMPORTANT TIPS: To safeguard the arcuate artery, it is advisable to sever the fibula with a muscle cuff measuring approximately 1 to 2 cm in length.The length of the fibula should be adjusted according to the surgical method utilized for the hip. Retain the fibula along with the peroneal arteriovenous vessels on the corresponding side, ensuring the preservation of the peroneal vessels to the greatest extent possible.To maintain ankle joint stability, it is necessary for the distal end of the fibula to be positioned at a minimum distance of 8 cm from the ankle joint following its removal.Prior to preparing the free fibula, it is important to carefully examine the side walls of the main vessels for any notable leakage. If leakage is detected, prompt repair should be performed.The period of weight-bearing should be established on the basis of postoperative radiographic follow-up in order to prevent weight-bearing too early, which can result in femoral head collapse and failure of the head preservation therapy.

ACRONYMS AND ABBREVIATIONS: CD = core decompressionCT = computed tomographyARCO = Association Research Circulation OsseousMRI = magnetic resonance imaging.

A 20-yr-old male patient presented with right hip pain and positive Flexion-Adduction-Internal-Rotation test. He underwent routine magnetic resonance imaging (MRI), followed by computed tomography (CT), and repeated contrast-enhanced MRI of the right hip to confirm the diagnosis. MRI showed a well-defined lesion at the right anterior femoral head-neck junction causing a loss of the femoral head-neck offset and an elevated alpha angle of 69 degrees. Notably, the lesion does not follow bone marrow signal on all sequences, as seen in typical bony cam lesions. The lesion is also beyond the cortical margins of the femur and does not appear as a bony bump. The lesion is of soft tissue attenuation on CT scan with associated subtle sclerosis in the adjacent bone. There was also tear of the anterior-superior acetabular labrum. Overall findings are supportive of soft cam lesion. The patient underwent right hip arthroscopy, labrum repair, soft tissue femoral cam resection, and capsule repair. Intraoperative image showed thickening of the femoral neck soft tissue, which was resected. Soft or nonossified cam lesion is likely an underrecognized entity with only few published literature. The etiology of conventional bony cam lesion in adolescents is uncertain, with Siebenrock et al. proposing epiphyseal extension in response to rigorous activities as a mechanism. Youngman et al. proposed that soft cam lesion may be a precursor to bony cam lesion in young patients, or its own entity, although this requires further research. Youngman et al. further classified soft cam lesion into thickened perichondral ring, periosteal thickening, or cartilaginous epiphyseal extension based on relationship to the physis and femoral neck. Unlike bony cam lesions, soft cam lesions can be occult on radiograph or CT; a radiographic Dunn view will not show an elevated alpha angle hence MRI is required for diagnosis. Given the paucity of published literature, our case serves as a good visual vignette on the spectrum of appearances across multiple MRI sequences, CT, and arthroscopy. Our case also demonstrated subtle bone sclerosis on CT adjacent to the soft cam lesion, a feature that was not previously described; we propose that this sclerosis may be reactive change to repetitive stress. Awareness of soft cam lesion is important to avoid missing the diagnosis of femoroacetabular impingement or to misdiagnosis it as neoplastic in nature.

OBJECTIVE: Femoroacetabular impingement syndrome (FAIS) is a prevalent cause of hip pain, characterized by distinctive motion patterns. However, the impact of surgical intervention on squatting biomechanics remains underexplored. This review aims to evaluate the effects of surgical treatment on biomechanical outcomes during squatting in patients with FAIS.

DATA SOURCES: A comprehensive search was conducted across multiple databases following PRISMA guidelines (Prospero registration number CRD42023473974). Data of longitudinal, prospective/retrospective cohorts, case-control, and clinical trial studies with 3-dimensional motion analysis describing kinematics and/or kinetics for any joint during squatting in patients with FAIS comparing presurgical to postsurgical biomechanical data on the same patients were included. Quality assessment was performed using MINORS criteria. Both qualitative and quantitative analyses were performed.

MAIN RESULTS: Six studies met the inclusion criteria for qualitative review and 5 were suitable for meta-analysis. The overall quality of the studies was moderate based on MINORS criteria. The postsurgical motion analysis was performed between 6 and 32 months postoperatively. Although most studies reported no significant changes in kinematic or kinetic variables postsurgery, individual studies reported specific increases in squat depth, pelvic sagittal range of motion, anterior pelvic tilt, hip and knee flexion, and ankle dorsiflexion angles. Meta-analysis revealed no significant differences in the kinematic parameters analyzed.

CONCLUSIONS: These findings underscore the multifaceted nature of FAIS, suggesting that bone deformities alone do not account for the biomechanical limitations observed during squatting in these patients. This highlights the need for further biomechanical investigations.

LEVEL OF EVIDENCE: Systematic Review of Level II-III studies.