Abstract:[Objective] To investigate the clinical efficacy of proximal femoral osteotomy combined with Steel pelvic osteotomy in thetreatment of severe Legg-Calvé-Perthes disease (LCPD). [Methods] A retrospective study was conducted on 38 patients who received surgi-cal treatments for severe LCPD in our hospitals from January 2013 to June 2021. According to doctor-patient communication, 17 patientswere treated with simple proximal femoral varus osteotomy (the femoral group), while the other 21 patients were treated with proximal femoralvarus osteotomy combined with Steel pelvic osteotomy (the combined group). The perioperative period, follow-up and imaging data of the twogroups were compared. [Results] The femoral group proved significantly less than the combined group in terms of operation time, incisionlength, intraoperative blood loss, postoperative drainage volume and hospital stay (P＜0.05). All patients in both groups were followed up for(33.0±9.6) months in a mean, and the femoral group resumed ambulation [(73.5±3.5) days vs (79.9±5.1) days, P＜0.05] and the full weightbearingactivity [(108.9±6.8) days vs (119.4±8.6) days, P＜0.05] significantly earlier than the combined group. Compared with those preopera-tively, the Harris score, hip flexion-extension range of motion (ROM) and internal-external rotation ROM significantly increased in bothgroups at the latest follow-up (P＜0.05), which proved not statistically significant between the two groups at any time points accordingly (P＞0.05). Radiographically, the acetabular index (AI), lateral center edge angle (LCEA), femoral head extrusion index (FHEI) and Sharp anglesignificantly improved at the last follow-up compared with those before surgery in both groups (P＜0.05). Although there was no statistical sig-nificance in the above radiographic parameters between the two groups before surgery (P＞0.05), the combined group was significantly superi-or to the femoral group in terms of AI [(11.3±2.0)° vs (16.7±1.7)°, P＜0.05], LCEA [(33.4±2.1)° vs (25.2±2.8)°, P＜0.05], FHEI [(12.2±3.3)%vs (17.8±3.0)%, P＜0.05], Sharp angle [(27.9±4.4)° vs (35.4±3.1)°, P＜0.05], whereas there was no statistical significance in Stulberg classifi-cation between the two groups (P＞0.05). [Conclusion] Compared with the femoral osteotomy alone, the femoral varus osteotomy combined with Steel pelvic osteotomy does achieve better femoral head containment that facilitate the recovery of femoral head, despite of greater surgi-cal trauma.