特発性大腿骨頭壊死症

OBJECTIVE: This study aimed to systematically review and compare the clinical and radiographic outcomes of different bone defect filler materials following lesion debridement for osteonecrosis of the femoral head (ONFH). Existing evidence on filler materials relies heavily on isolated pairwise comparisons, leaving the optimal reconstruction strategy undefined. Therefore, the current network meta-analysis integrates multiple treatments and diverse clinical endpoints to determine the most effective reconstructive option. With increasing recognition of the importance of intraosseous structural reconstruction, this study sought to provide evidence-based guidance for filler selection in hip-preserving treatment. METHODS: PubMed, MEDLINE, Embase, the Cochrane Library, Web of Science, and Scopus were searched from inception to March 2026. Comparative clinical studies evaluating two or more bone defect filler materials after lesion debridement for ONFH were included. Evidence was synthesized using a Bayesian random-effects network meta-analysis. Methodological quality and risk of bias were assessed using the Cochrane Risk of Bias Tool 2.0 for randomized controlled trials (RCTs) and a modified Newcastle-Ottawa Scale for non-randomized comparative trials (NCTs). RESULTS: After screening 2046 records, 18 eligible studies were included, comprising 10 RCTs and 8 NCTs, with a total of 1176 patients and 1284 hips. Fourteen filler strategies were analyzed, including without graft, allograft, tantalum rods, iliac autograft, artificial bone, fibular autograft, vascularized iliac autograft, vascularized fibular autograft, artificial bone combined with iliac autograft, tantalum rods combined with autograft or allograft, other autografts, other autografts combined with vascularized greater trochanter graft, iliac autograft with screw fixation, and vascularized iliac autograft with screw fixation. Tantalum rods combined with bone graft showed relative advantages in functional recovery and pain relief, as assessed by the Harris Hip Score and Visual Analogue Scale. However, tantalum rods alone were associated with a higher rate of conversion to total hip arthroplasty. Allograft ranked favorably for early functional recovery and necrosis stage maintenance, although no significant differences were observed among interventions for necrosis stage maintenance. Iliac autograft with screw fixation ranked first in preventing radiographic progression. However, without significant pairwise differences, this ranking remains inconclusive. CONCLUSION: Considering postoperative functional recovery, pain relief, and disease progression after lesion debridement, tantalum rods combined with bone graft may provide advantages in early outcomes, but the long-term failure risk of tantalum rods alone should be carefully considered. Allograft and iliac autograft with screw fixation showed favorable profiles in specific outcome domains and may represent balanced options in selected patients. Further high-quality studies with longer follow-up are needed to validate the long-term efficacy of different filler strategies.

Objective: To explore the feasibility and short-term outcomes of the jackknife position transanal-priority intersphincteric space (ISS) dissection combined with the modified Bacon procedure for special types of ultra-low rectal cancer. Methods: A retrospective observational study was performed. Clinical data of 7 patients with ultra-low rectal cancer who underwent transanal-first ISS dissection combined with modified Bacon technique for staged reconstruction at Zhongnan Hospital of Wuhan University between September 2024 and August 2025 were retrospectively analyzed. The patients were aged (58.3±11.2) years with a body mass index of (23.0±2.9) kg/m². Based on preoperative pelvic MRI measurement, the median distance from the inferior tumor margin to the anal verge was 3.0 (2.4, 3.4) cm. Four patients received neoadjuvant chemoradiotherapy and achieved tumor regression. Among the 7 patients, preoperative imaging and digital rectal examination indicated anterior wall tumor involvement (partial or circumferential) in 6 cases, and tumor located at the right posterior wall in 1 case; one patient was complicated with drug-induced osteonecrosis of the femoral head and could not tolerate the conventional lithotomy position. Perioperative parameters and short-term oncological outcomes were analyzed. Results: All seven patients underwent successful laparoscopic surgery without conversion to open surgery or prophylactic stoma creation. The median operative time was 210 (180, 220) minutes, with intraoperative blood loss of 50 (50, 100) ml. Two perioperative complications occurred, both resolved conservatively. All cases achieved negative circumferential margins with a distal margin distance of 1.0 (0.5, 1.3) cm. Median follow-up was 18 (13, 19) months, with one case showing distant metastasis and no recurrence in the remaining patients. Overall, patients reported satisfactory anal function. Conclusion: The combination of the jackknife position transanal-priority ISS dissection and the modified Bacon procedure is a feasible and safe sphincter-preserving strategy for patients with ultra-low rectal cancer characterized by unfavorable tumor location, challenging anatomy, or high anastomotic risk. It serves as an effective supplementary option for managing such complex cases.

OBJECTIVE: To investigate the biomechanical characteristics of the CT-based lateral classification of Japanese Investigation Committee (JIC) type C1 osteonecrosis of the femoral head (ONFH) under different necrotic extents using finite element analysis, and to evaluate the validity of the CT-based lateral classification for assessing the risk of femoral head collapse. METHODS: A finite element model of the hip joint was established based on CT data from a healthy 35-year-old male volunteer. According to the JIC C1 classification criteria, three necrotic extents were defined in the coronal plane: M1 (30%), M2 (50%), and M3 (70%). According to the sagittal location of the necrotic lesion, the femoral head was equally divided into anterior, middle, and posterior regions, and five types of the CT-based lateral classification were defined: type 1, involvement of the anterior region only; type 2, involvement of the anterior and middle regions; type 3, involvement of the anterior, middle, and posterior regions; type 4, involvement of the middle and posterior regions; and type 5, involvement of the posterior region only. A total of 15 finite element models were constructed by combining the three necrotic extents with the five CT-based lateral classification types. Bilateral standing loading was simulated, and the maximum von Mises stress and maximum displacement of the femoral head surface and necrotic region were recorded. RESULTS: Stress concentration was mainly located in the superolateral region of the femoral head directly above the necrotic lesion, consistent with previous studies. Within the same CT-based lateral classification type, increases in necrotic extent from M1 to M3 were associated with significant increases in the maximum von Mises stress and maximum displacement of the femoral head surface, as well as the maximum displacement of the necrotic region. No significant difference was found in the maximum von Mises stress in the necrotic region among M1, M2, and M3 groups ( P>0.05). Except for the differences in the maximum von Mises stress on the femoral head surface between groups M2 and M3, and the differences in the maximum displacement in the necrosis region between groups M1 and M2 ( P>0.05), there were significant differences in the maximum von Mises stress on the femoral head surface, the maximum displacement on the femoral head surface, and the maximum displacement in the necrosis region between other groups ( P<0.05). At the same necrotic extent, the maximum von Mises stress and maximum displacement on the femoral head surface and in the necrosis region were significantly higher in type 3 than in other types; followed by type 2>type 1>type 4>type 5. Among them, there was no significant difference in the maximum von Mises stress on the femoral head surface between types 1 and 4, types 2 and 3, and the maximum displacement on the femoral head surface between types 1 and 2, types 2 and 3, types 4 and 5, as well as the maximum von Mises stress in the necrosis region between types 4 and 5, and the maximum displacement in the necrosis region between types 1 and 2, types 4 and 5, types 2 and 3, and types 4 and 5 ( P>0.05); all other comparisons between different types showed significant differences ( P<0.05). CONCLUSION: Both the location and extent of osteonecrosis affect the biomechanical stability of the femoral head, with lesion location, particularly involvement of the anterior weight-bearing region, exerting a greater influence on stress distribution. The CT-based lateral classification can effectively distinguish biomechanical differences associated with different necrotic locations and may provide a useful reference for evaluating the risk of femoral head collapse and guiding individualized treatment in patients with JIC type C1 ONFH.

BACKGROUND: Avascular necrosis of the femoral head, a known long-term complication following traumatic posterior hip dislocation, can result in femoral head collapse, osteochondral defects, and eventual posttraumatic osteoarthritis. This condition is especially problematic in young, active patients for whom total hip arthroplasty survivorship is a concern. Biologic treatments are therefore preferable to delay or avoid total hip arthroplasty. CASE REPORT: A 16-year-old male developed progressive left hip pain after a posterior dislocation sustained while playing football. The hip was emergently reduced. Imaging (x-ray, computed tomography, and magnetic resonance imaging [MRI]) showed a small depressed cortical fracture on the anterior and superior femoral head. Conservative treatment included protected weight-bearing for 6 weeks, knee immobilization to restrict hip flexion, physical therapy, and a home exercise program. However, symptoms worsened after 5 months of conservative care. Repeat MRI demonstrated avascular necrosis with associated cartilage loss, hip effusion, and femoroacetabular impingement (a cam deformity). Given the patient's young age, persistent symptoms, functional limitations, and radiographic findings, the decision was made to perform surgical intervention. Surgical hip dislocation via an anterolateral approach with a small trochanteric osteotomy (modified Hardinge approach) was used to expose the femoral head while maintaining the remaining blood supply. Fresh femoral head osteochondral allograft transplantation was performed, along with femoral neck osteoplasty to address the cam deformity. CONCLUSION: Osteochondral allograft transplantation is an effective technique to treat osteochondral defects of the femoral head in the setting of avascular necrosis following traumatic hip dislocation. This surgical option restores hip function and may delay or prevent total hip arthroplasty in young, active patients.

UNLABELLED: The classical "vascular occlusion" model does not fully account for osteonecrosis of the femoral head (ONFH). Femoral head collapse may progress despite restored perfusion, and ischemia alone cannot adequately explain steroid-associated ONFH. We propose that ONFH involves disruption of bone-vascular-immune homeostasis, with macrophage immunometabolic reprogramming in response to hypoxic and lipotoxic stress acting as a potential driver of inflammatory repair failure. Among the metabolic mechanisms implicated in ONFH, the strongest disease-specific evidence supports roles for hypoxia, oxidative stress, disordered lipid metabolism, macrophage imbalance, and ferroptosis-associated injury. By contrast, macrophage-specific glycolytic reprogramming, remodeling of the tricarboxylic acid (TCA) cycle, epigenetic fixation, osteomac dysfunction, and cuproptosis remain less well established. Regulated cell death pathways, particularly ferroptosis and pyroptosis, may exacerbate local tissue injury by releasing damage-associated molecular patterns (DAMPs) and inflammatory mediators that disrupt type H vessel-osteogenesis coupling and shift repair toward fibrosis. Establishing causal relationships rather than correlative associations will require lineage-tracing experiments, spatial validation, metabolic flux analyses, and genetic loss-of-function studies in ONFH models. THE TRANSLATIONAL POTENTIAL OF THIS ARTICLE: Viewing ONFH as an immunometabolic disorder identifies experimentally tractable targets beyond conventional anti-inflammatory strategies, including SLC7A11/GPX4-dependent ferroptosis defense, NLRP3 inflammasome signaling, and HIF-1α-associated macrophage metabolic adaptation. Extracellular vesicle- or biomaterial-based delivery systems designed for prolonged local retention should currently be considered experimental platforms for assessing lesion-specific target engagement in early-stage ONFH. Their clinical relevance must be established through ONFH-specific studies evaluating efficacy, safety, biodistribution, manufacturability, and long-term structural outcomes.