Background Intra-articular injections containing a corticosteroid are used frequently, and periprosthetic joint infection is a serious complication after total joint arthroplasty. There is debate regarding whether intraarticular corticosteroid injections before arthroplasty increase periprosthetic joint infection after surgery. Questions/purposes (1) Does a previous intra-articular corticosteroid injection increase the odds of infection after subsequent hip or knee arthroplasty? (2) Does this risk vary based on how soon before the arthroplasty (such as less than 3 months before surgery) the injection is administered?Methods Using the PubMed, Embase, Cochrane Library, and Web of Science databases from inception to July 2021, we searched for comparative studies in English on patients who received intra-articular corticosteroid injections before arthroplasty and that tracked the frequency of infection after arthroplasty. We extracted data on the risk of infection after subsequent joint arthroplasty. The keywords included "corticosteroid," "steroid," "arthroplasty," "knee replacement," and "hip replacement." Eleven retrospective, comparative studies from four countries were included, of which 10 reported the specific diagnosis criteria and oneThe institution of one or more of the authors (QZ) has received, during the study period, funding from the Natural Science Foundation of Guangdong (2015A030313353). The institution of one or more of the authors (CZ) has received, during the study period, funding from the Research Project of Innovating to Strengthen the First Hospital of Guangzhou University of Chinese Medicine (2019IIT06). Each author certifies that there are no funding or commercial associations (consultancies, stock ownership, equity interest, patent/licensing arrangements, etc.) that might pose a conflict of interest in connection with the submitted article related to the author or any immediate family members. All ICMJE Conflict of Interest Forms for authors and Clinical Orthopaedics and Related Research® editors and board members are on file with the publication and can be viewed on request.

Purpose Our research developed a novel approach to quantitatively evaluate the boundary of necrotic lesions in osteonecrosis of the femoral head (ONFH) and to explore its diagnostic value in predicting bone collapse of the femoral head. Methods A retrospective cross-sectional study was conducted in our institution, and 146 hips (121 cases) identified as ONFH were recruited. The anterior and lateral boundaries of each enrolled subject were measured in standard anteroposterior (AP) view and frog-leg (FL) view of plain radiographic images, the intact rate of which was then calculated and presented as the anteroposterior view intact ratio (APIR) and frog-leg view intact ratio (FLIR), respectively. Univariate and multivariate logistic regression analyses were performed to identify risk factors for collapse. A receiver operating characteristic (ROC) curve analysis was performed to determine the sensitivity, specificity and cutoff value of the APIR and FLIR. A Kaplan-Meier (K-M) analysis was applied to calculate the survival rate of the femoral head, and bone collapse of the femoral head was regarded as the endpoint. Results Femoral head collapse was observed in 61 hips during the follow-up period. Patients with or without femoral head collapse were categorized into the collapse group and non-collapse group, respectively. The mean follow-up time was 3.7 years (2-9) for the collapse group and 7.7 years (5-20) for the non-collapse group. Univariate and multivariate logistic regression analysis and ROC analysis showed that APIR (< 25.61%) and FLIR (< 24.43%) were significantly associated with femoral head collapse. The K-M survival curves indicated that the overall survival rate of APIR (≥ 25.61%) was 94.8% at 7.5 years and 76.6% at 10 years, while that of FLIR (≥ 24.43%) was 87.3% at 7.5 years and ten years. ConclusionThe present study demonstrates that APIR and FLIR are of high diagnostic value in the early and middle stages of ONFH. APIR and FLIR can be used to predict the occurrence of femoral head collapse in patients with JIC classification types B and C1. The measurement of these two parameters in plain radiography images may contribute to the selection of a proper hip preservation strategy. Keywords Osteonecrosis of the femoral head • Collapse • Anteroposterior view intact ratio • Frog-leg view intact ratioYinuo Fan and Jiahao Zhang contributed equally to this work.

Objective: Core decompression bone grafting usually is used hip-preserving approach for osteonecrosis of femoral head (ONFH). Platelet-rich plasma (PRP) is an adjuvant therapy, combined with core decompression bone grafting for ONFH. However, it remains controversial. Therefore, its efficacy was systematically evaluated and meta-analysis in this study.Methods: Literature on core decompression bone grafting for ONFH was retrieved in CNKI, Wan Fang, PubMed, Embase, Cochrane Library and Web of Science from inception to March 2021. Review Manager 5.3 software and Stata 12.0 software were used for data synthesis.Results: A total of 10 RCTs were included. The results showed at final follow-up that, Harris hip score was significantly difference in the treatment group, adjuvant therapy with PRP (group A) better than the control group (group B), MD=7.53 [95%CI (5.29,9.77)]，P < 0.00001. There was MD=-0.71[95%CI (-0.96, -0.46)], P < 0.00001, of visual analog scale (VAS) of hip pain between the two groups. The excellent and good rate of function of hip was 1.42-fold higher in group A than that in group B, RR=1.42, 95%CI (1.25,1.62), P<0.00001. The progression and total hip arthroplasty were showed improvements, RR=0.37,95%CI (0.21,0.65), P=0.0006 and RR=0.39,95%CI (0.18,0.85), P=0.02, respectively. Begg's and Egger's tests did not indicate publication bias.Conclusion: It was shown that the use of PRP combined with core decompression bone grafting improved the symptoms better than core decompression bone grafting only, and might delay progression and total hip arthroplasty. However, as the study’s limitations, it needed to be fully verified by more large-sample multicenter prospective clinical studies.

Purposes The purpose of this study was to investigate the predictive effect exerted by composite indices of femoral neck strength (compressive strength index (CSI), bending strength index (BSI) and impact strength index (ISI) on the femoral head collapse in steroid-associated ONFH patients. Methods Nonoperative steroid-associated osteonecrosis of the femoral head (ONFH) patients from 2017 to 2019 were selected. The patients fell into the collapsed group and the non-collapsed group according to whether the femoral head collapsed. CSI, BSI and ISI were calculated. Moreover, bone turnover markers were measured. The statistical analysis was conducted on the predictive effects of composite indices of femoral neck strength and bone turnover index on ONFH collapse. Results A total of 62 patients were included. The mean CSI, BSI and ISI were significantly lower in the collapsed group than those in the non-collapsed group (P < 0.05). CSI, ISI,t-P1NP and β-CTx were suggested as the protective risk factors for the femoral head collapse in ONFH patients. The ISI area under the curve values was 0. 878.The mean survival time of the hips of patients with ISI greater than 0.435 was greater (P < 0.05) than that of patients with ISI less than 0.435. Conclusion The composite indices of femoral neck strength can predict steroid-associated ONFH femoral head collapse more effectively than the bone turnover markers. The ISI value of 0.435 is a potential cut-off value, lower than this value can predict the early collapse of steroid-associated ONFH.

Background Traditional observational studies have found an increased risk of internal knee derangement (IKD) associated with higher body mass index (BMI). Here, we hypothesized that BMI and the risk of IKD have a causal relationship, and that high BMI is more likely to suffer from IKD. Method By reading the results of previous studies, we can assume that high BMI can increase the risk of IKD. The instrumental variables of BMI were obtained from the GIANT GWAS meta-analysis, which included approximately 700,000 individuals of European descent (n = 681,275). The IKD genetic data from IEU database, comprising 16,380,251 SNPs of European population. We performed MR analysis mainly by inverse-variance weighted (IVW), MR-Egger, Weighted median. In order to test the robustness of the correlation, we further conducted sensitivity analysis through Cochran’s Q test, MR-Egger intercept test and leave-one-out analysis. Results Genetic predisposition to higher BMI by 1 SD (SD = 4.8kg/m2) was associated with 49% higher risk of IKD (OR = 1.491; [95%CI: 1.373–1.619]; p = 1.932e-21༜0.05). Sensitivity analysis was consistent with causal interpretation, which shows that there is unlikely to be a major bias in genetic pleiotropy. Conclusions Our findings indicated that high BMI predicted by genes exerts a causal effect on increasing the risk of IKD. Further research is required to unravel the mechanism of BMI in IKD prevention.