Efficacy and safety of robot-assisted core decompression for osteonecrosis of the femoral head: a meta-analysis of single-arm studies

Abstract 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).