Abstract:[Objective] To explore the effectiveness of circumferential reduction technique in treatment of irreducible intertrochanteric fractures of the femur (IRIFF) with lesser trochanter bisection fractures. [Methods] Between January 2020 and December 2022, 18 patients received circumferential reduction and proximal femoral nail fixation for IRIFF with lesser trochanter bisection fracture. The operative duration, blood loss, reduction quality, VAS score and Harris score at 4-week postoperatively and the latest follow-up were recorded and evaluated. [Results] All patients in this group had operation performed successfully with the operative time of (39.7±7.0) min, and the intraoperative blood loss of (124.7±50.0) mL. All patients were followed up for (11.7±2.1) months, one of them underwent revision surgery of hip hemiarthro- plasty due to implant loosening. With time preoperatively, 4 weeks postoperatively and at the latest followup, the VAS score [(6.4±1.1), (2.8±1.5), (0.7±1.1), P＜0.001], Harris score [(37.9±8.3), (71.6±10.8), (92.7±10.3), P 0.001], hip flexion-extension ROM [(5.3±4.4)°, (67.4± 13.0)°, (97.2±13.0)°, P 0.001] were significantly improved. Radiographically, the femoral neck-shaft angle of the affected hip [(76.5±8.2)°, (129.1±4.9)°, (125.1±7.0)°, P 0.001] was significantly increased at 4 months after surgery and the last follow-up compared with those preoperatively. However, the tip-apex distance of the implant remained unchanged at the latest follow-up compared with that 4 weeks after operation (P＞0.05). Of them, 17 patients got primary fracture healing with the healing time of (6.6±1.5) months. [Conclusion] The circumferential reduction technique does effectively reduce irreducible intertrochanteric fracture of the femurfor proximal femoral nail fixation, and achieves satisfactory clinical outcome.