Aims. Pain is the most frequent complaint associated with osteonecrosis of the femoral head (ONFH), but the factors contributing to such pain are poorly understood. This study explored diverse demographic, clinical, radiological, psychological, and neurophysiological factors for their potential contribution to pain in patients with ONFH. Methods. This cross-sectional study was carried out according to the “STrengthening the Reporting of OBservational studies in Epidemiology” statement. Data on 19 variables were collected at a single timepoint from 250 patients with ONFH who were treated at our medical centre between July and December 2023 using validated instruments or, in the case of hip pain, a numerical rating scale. Factors associated with pain severity were identified using hierarchical multifactor linear regression. Results. Regression identified the following characteristics as independently associated with higher pain score, after adjustment for potential confounders: Association Research Circulation Osseous classification stage IIIa or IIIb, bone marrow oedema, grade 3 joint effusion, as well as higher scores on pain catastrophizing, anxiety, and central sensitization. The final model explained 69.7% of observed variance in pain scores, of which clinical and radiological factors explained 37%, while psychological and neurophysiological factors explained 24% and demographic factors explained 8.7%. Conclusion. Multidimensional characteristics jointly contribute to the severity of pain associated with ONFH. These findings highlight the need to comprehensively identify potential contributors to pain, and to personalize management and treatment accordingly. Cite this article: Bone Joint Res 2024;13(11):673–681

Aims. The aim of this study was to report the medium-term outcomes of impaction bone allograft and fibular grafting for osteonecrosis of the femoral head (ONFH) and to define the optimal indications. Methods. A total of 67 patients (77 hips) with ONFH were enrolled in a single centre retrospective review. Success of the procedure was assessed using the Harris Hip Score (HHS) and rate of revision to total hip arthroplasty (THA). Risk factors were studied, including age, aetiology, duration of hip pain, as well as two classification systems (Association Research Circulation Osseous (ARCO) and Japanese Investigation Committee (JIC) systems). Results. After a mean follow-up period of 8.61 years (SD 1.45), 81.3% (52/64) of enrolled cases had a good or excellent HHS at latest follow-up (declining to 76.0% (38/50) for those with more than eight years of follow-up). Overall survival was 92.1% at eight years’ follow-up (95% CI 83.2% to 96.4%). A total of 12 hips (19.0%) failed (reoperation or HHS < 70 points) at final follow-up. Rate of success was adversely affected by increasing age, duration of pain, and more severe disease as measured using the ARCO and JIC classifications, but not by aetiology of the ONFH. Conclusion. We report favourable medium-term results of this procedure. Best outcomes can be expected in patients matching the following indications: younger than 40 years; less 12-month hip pain before surgery; femoral head collapse being less than 2 mm; and integrated lateral wall of femoral head. Cite this article: Bone Joint J 2020;102-B(7):838–844

Aims. We compared the clinical outcomes of curved intertrochanteric varus osteotomy (CVO) with bone impaction grafting (BIG) with CVO alone for the treatment of osteonecrosis of the femoral head (ONFH). Methods. This retrospective comparative study included 81 patients with ONFH; 37 patients (40 hips) underwent CVO with BIG (BIG group) and 44 patients (47 hips) underwent CVO alone (CVO group). Patients in the BIG group were followed-up for a mean of 12.2 years (10.0 to 16.5). Patients in the CVO group were followed-up for a mean of 14.5 years (10.0 to 21.0). Assessment parameters included the Harris Hip Score (HHS), Oxford Hip Score (OHS), Japanese Orthopaedic Association Hip-Disease Evaluation Questionnaire (JHEQ), complication rates, and survival rates, with conversion to total hip arthroplasty (THA) and radiological failure as the endpoints. Results. There were no significant differences in preoperative and postoperative HHS or postoperative OHS and JHEQ between the BIG group and the CVO group. Complication rates were comparable between groups. Ten-year survival rates with conversion to THA and radiological failure as the endpoints were not significantly different between groups. Successful CVO (postoperative coverage ratio of more than one-third) exhibited better ten-year survival rates with radiological failure as the endpoint in the BIG group (91.4%) than in the CVO group (77.7%), but this difference was not significant (p = 0.079). Conclusion. Long-term outcomes of CVO with BIG were favourable when proper patient selection and accurate surgery are performed. However, this study did not show improvements in treatment results with the concomitant use of BIG. Cite this article: Bone Joint J 2021;103-B(4):665–671

Objectives. Using a simple classification method, we aimed to estimate the collapse rate due to osteonecrosis of the femoral head (ONFH) in order to develop treatment guidelines for joint-preserving surgeries. Methods. We retrospectively analyzed 505 hips from 310 patients (141 men, 169 women; mean age 45.5 years . (sd. 14.9; 15 to 86)) diagnosed with ONFH and classified them using the Japanese Investigation Committee (JIC) classification. The JIC system includes four visualized types based on the location and size of osteonecrotic lesions on weightbearing surfaces (types A, B, C1, and C2) and the stage of ONFH. The collapse rate due to ONFH was calculated using Kaplan–Meier survival analysis, with radiological collapse/arthroplasty as endpoints. Results. Bilateral cases accounted for 390 hips, while unilateral cases accounted for 115. According to the JIC types, 21 hips were type A, 34 were type B, 173 were type C1, and 277 were type C2. At initial diagnosis, 238/505 hips (47.0%) had already collapsed. Further, the cumulative survival rate was analyzed in 212 precollapsed hips, and the two-year and five-year collapse rates were found to be 0% and 0%, 7.9% and 7.9%, 23.2% and 36.6%, and 57.8% and 84.8% for types A, B, C1, and C2, respectively. Conclusion. Type A ONFH needs no further treatment, but precollapse type C2 ONFH warrants immediate treatment with joint-preserving surgery. Considering the high collapse rate, our study results justify the importance of early diagnosis and intervention in asymptomatic patients with type C2 ONFH. Cite this article: Y. Kuroda, T. Tanaka, T. Miyagawa, T. Kawai, K. Goto, S. Tanaka, S. Matsuda, H. Akiyama. Classification of osteonecrosis of the femoral head: Who should have surgery?. Bone Joint Res 2019;8:451–458. DOI: 10.1302/2046-3758.810.BJR-2019-0022.R1

Aims. Earlier studies dealing with trends in the management of osteonecrosis of the femoral head (ONFH) identified an increasing rate of total hip arthroplasties (THAs) and a decreasing rate of joint-preserving procedures between 1992 and 2008. In an effort to assess new trends in the management of this condition, this study evaluated the annual trends of joint-preserving versus arthroplasties for patients aged < or > 50 years old, and the incidence of specific operative management techniques. Methods. A total of 219,371 patients with ONFH were identified from a nationwide database between 1 January 2009 and 31 December 2015. The mean age was 54 years (18 to 90) and 105,298 (48%) were female. The diagnosis was made using International Classification of Disease, Ninth revision, Clinical Modification (ICD-9-CM) and Tenth Revision, Clinical Modification (ICD-10-CM) procedure codes. The percentage of patients managed using each procedure during each year was calculated and compared between years. The trends in the use of the types of procedure were also evaluated. Results. The rate of joint-preserving procedures was significantly higher in patients aged < 50 years compared with those aged > 50 years (4.93% vs 1.52%; p < 0.001). For the overall cohort, rates of arthroplasty were far greater than those for joint-preserving procedures. THA was the most commonly performed procedure (291,114; 94.03%), while osteotomy (3,598; 1.16%), partial arthroplasty (9,171; 2.96%), core decompression (1,200; 0.39%), and bone graft (3,026; 0.98%) were performed markedly less frequently. The annual percentage of patients managed using a THA (93.56% to 89.52%; p < 0.001), resurfacing (1.22% to 0.19%; p < 0.001), and osteotomy (1.31% to 1.05%; p < 0.001) also decreased during the study period. Conclusion. We found that patients with ONFH have been most commonly managed with non-joint-preserving procedures. Our findings provide valuable insight into the current management of this condition and should increase efforts being made to save the hip joint. Cite this article: Bone Joint J 2020;102-B(7 Supple B):122–128

Aims. The localization of necrotic areas has been reported to impact the prognosis and treatment strategy for osteonecrosis of the femoral head (ONFH). Anteroposterior localization of the necrotic area after a femoral neck fracture (FNF) has not been properly investigated. We hypothesize that the change of the weight loading direction on the femoral head due to residual posterior tilt caused by malunited FNF may affect the location of ONFH. We investigate the relationship between the posterior tilt angle (PTA) and anteroposterior localization of osteonecrosis using lateral hip radiographs. Methods. Patients aged younger than 55 years diagnosed with ONFH after FNF were retrospectively reviewed. Overall, 65 hips (38 males and 27 females; mean age 32.6 years (SD 12.2)) met the inclusion criteria. Patients with stage 1 or 4 ONFH, as per the Association Research Circulation Osseous classification, were excluded. The ratios of anterior and posterior viable areas and necrotic areas of the femoral head to the articular surface were calculated by setting the femoral head centre as the reference point. The PTA was measured using Palm’s method. The association between the PTA and viable or necrotic areas of the femoral head was assessed using Spearman’s rank correlation analysis (median PTA 6.0° (interquartile range 3 to 11.5)). Results. We identified a negative correlation between PTA and anterior viable areas (rho −0.477; p = 0.001), and no correlation between PTA and necrotic (rho 0.229; p = 0.067) or posterior viable areas (rho 0.204; p = 0.132). Conclusion. Our results suggest that residual posterior tilt after FNF could affect the anteroposterior localization of necrosis. Cite this article: Bone Jt Open 2024;5(5):394–400

It has been suggested that transient osteoporosis or the bone marrow oedema syndrome (BMOS) may be the initial phase of osteonecrosis of the femoral head (ONFH) and that there may be a common pathophysiology. In this study, we have assessed the MR images of 200 consecutive patients with ONFH in respect of the BMO pattern in order to test this hypothesis. This pattern was not observed in the early stage of ONFH. The initial abnormal finding detected on the MR images was an abnormal band of intensity at the junction between the necrotic area and the normal bone. Structural damage of the head seems to result in the appearance of the BMO pattern and the development of pain in ONFH. There was no finding to support the existence of a continuum between BMOS and ONFH

Six major and seven minor diagnostic criteria have been developed by the Japanese Investigation Committee for osteonecrosis of the femoral head (ONFH). We have carried out a multicentre study to clarify these. We studied prospectively 277 hips in 222 patients, from six hospitals, who had ONFH and other hip pathology and from whom histological material was available. We identified five criteria with high specificity: 1) collapse of the femoral head without narrowing of the joint space or acetabular abnormality on radiographs, including the crescent sign; 2) demarcating sclerosis in the femoral head without narrowing or acetabular abnormality; 3) a ‘cold-in-hot’ appearance on the bone scan; 4) a low-intensity band on T1-weighted images (band pattern); and 5) evidence of trabecular and marrow necrosis on histological examination. With any combination of two of these criteria, the sensitivity and specificity of the diagnosis were 91% and 99%, respectively

Aims

Successful cell therapy in hip osteonecrosis (ON) may help to avoid ON progression or total hip arthroplasty (THA), but the achieved bone regeneration is unclear. The aim of this study was to evaluate amount and location of bone regeneration obtained after surgical injection of expanded autologous mesenchymal stromal cells from the bone marrow (BM-hMSCs).

Aims

The aim of this study was to evaluate the suitability of the tapered cone stem in total hip arthroplasty (THA) in patients with excessive femoral anteversion and after femoral osteotomy.

Aims

The purpose of this study was to examine whether leg-length discrepancy (LLD) following unilateral total hip arthroplasty (THA) affects the incidence of contralateral head collapse and subsequent THA in patients with bilateral osteonecrosis, and to determine factors associated with subsequent collapse.

The systemic use of steroids and habitual alcohol intake are two major causative factors in the development of idiopathic osteonecrosis of the femoral head (ONFH). To examine any interaction between oral corticosteroid use and alcohol intake on the risk of ONFH, we conducted a hospital-based case-control study of 71 cases with ONFH (mean age 45 years (20 to 79)) and 227 matched controls (mean age 47 years (18 to 79)). Alcohol intake was positively associated with ONFH among all subjects: the adjusted odds ratio (OR) of subjects with ≥ 3032 drink-years was 3.93 (95% confidence interval (CI) 1.18 to 13.1) compared with never-drinkers. When stratified by steroid use, the OR of such drinkers was 11.1 (95% CI 1.30 to 95.5) among those who had never used steroids, but 1.10 (95% CI 0.21 to 4.79) among those who had. When we assessed any interaction based on a two-by-two table of alcohol and steroid use, the OR of those non-drinkers who did use steroids was markedly elevated (OR 31.5) compared with users of neither. However, no further increase in OR was noted for the effect of using both (OR 31.6). We detected neither a multiplicative nor an additive interaction (p for multiplicative interaction 0.19; synergy index 0.95), suggesting that the added effect of alcohol may be trivial compared with the overwhelming effect of steroids in the development of ONFH.

Cite this article: Bone Joint J 2013;95-B:320–5.