ObjectivesCirculating exosomes represent novel biomarkers for multiple diseases. In this study, we investigated whether circulating exosome levels could be used as a diagnostic biomarker for steroid-induced osteonecrosis of the femoral head (ONFH).MethodsWe assessed the serum exosome level of 85 patients with steroid-induced ONFH and 115 healthy donors by Nanosight detection. We then assessed the diagnostic accuracy of serum exosomes by receiver operating characteristic curve analysis.ResultsThe circulating exosome level of the ONFH group was significantly lower than that of control group. The area under the curve was 0.72, suggesting that the level of serum exosomes has moderate diagnostic accuracy for steroid-induced ONFH.ConclusionCirculating exosome levels are valuable in the diagnosis of steroid-induced ONFH.Cite this article: H-Y. Zhu, Y-C. Gao, Y. Wang, C-Q. Zhang. Circulating exosome levels in the diagnosis of steroid-induced osteonecrosis of the femoral head. Bone Joint Res 2016;5:276–279. DOI: 10.1302/2046-3758.56.BJR-2015-0014.R1.

Vascular injury is considered an important pathological process during glucocorticoid (GC)-induced osteonecrosis of the femoral head (ONFH). In this study, we tried to investigate whether the endoplasmic reticulum (ER) stress is triggered in the GC-induced endotheliocyte (EC) apoptosis and ONFH. The results showed that a GC upregulated the expression of ER stress-related proteins, and PERK-CHOP signaling played an important role and induced EC apoptosis. The inhibition of PERK by GSK2656157 significantly decreased the GC-induced EC apoptosis in vitro and in vivo, thus protecting a rat model from vascular injury and significantly preventing GC-induced ONFH.

Background: The purpose of this study was to evaluate the long-term efficacy and prognostic factors predicting success of revision surgery with free vascularized fibular grafting (FVFG) for treatment of femoral neck nonunion. Methods: We prospectively enrolled patients who underwent revision surgery with FVFG between January 2001 and January 2013 in a tertiary hospital in China. A total of 98 patients with a minimum 5-year follow-up were included for analysis. The criteria for FVFG failure were conversion to hip arthroplasty, recommendation for a hip arthroplasty, or a Harris hip score of <80 points. Demographic information, the preoperative neck shortening ratio (NSR), the fixation method, and postoperative radiographic parameters including the postoperative NSR and neck-shaft angle (NSA) were recorded for prognostic analysis. Results: At an average of 9.8 ± 3.5 years (range, 3 to 17 years) postoperatively, the overall success rate of this surgical procedure was 77% (75 of 98). The success and failure groups had no significant differences in age, fixation method, interval between initial fixation and revision surgery, or postoperative NSA. The success group had a significantly higher NSR than the failure group both preoperatively (77.8% versus 62.4%, p < 0.001) and postoperatively (87.6% versus 78.4%, p = 0.001). The receiver operating characteristic (ROC) curve analysis revealed an optimal cutoff for preoperative NSR of 60% to predict the outcome. Patients with a preoperative NSR of >60% had a success rate of 91% (68 of 75). Conclusions: Revision surgery with FVFG and internal fixation is an effective and important option for treating nonunion of the femoral neck in young patients without severe preoperative shortening and neck resorption (preoperative NSR of >60%). Level of Evidence: Therapeutic Level IV. See Instructions for Authors for a complete description of levels of evidence.