Abstract: Objective To investigate the efficacy of biological extended stem hemiarthroplasty for elderly patients with unstable intertrochanteric fractures of the femur.Methods A retrospective analysis was conducted on 80 elderly patients with unstable intertrochanteric fractures of the femur treated with biological extended stem hemiarthroplasty from February 2018 to February 2023.The Harris score was used to evaluate the efficacy of hip joint function.Results All 80 cases were followed up for an average follow-up time of 10.3 (6~22) months.After 6 months of surgery,the hip joint function recovered according to Harris score with an average score of 85.6 (72~94).Among them,42 cases were excellent,28 cases were good,and 10 cases were still good,with a good rate of 87.5%．Conclusions The selection of biological extended stem hemiarthroplasty for the treatment of unstable intertrochanteric fractures of the femur in elderly patients has the advantage of fast postoperative recovery,early weight bearing,reduced various complications of long-term bed rest,and achieved good joint function．

Key words: Objective , To investigate the efficacy of biological extended stem hemiarthroplasty for elderly patients with unstable intertrochanteric fractures of the femur.Methods , A retrospective analysis was conducted on 80 elderly patients with unstable intertrochanteric fractures of the femur treated with biological extended stem hemiarthroplasty from February 2018 to February 2023.The Harris score was used to evaluate the efficacy of hip joint function.Results , All 80 cases were followed up for an average follow-up time of 10.3 (6~22) months.After 6 months of surgery,the hip joint function recovered according to Harris score with an average score of 85.6 (72~94).Among them,42 cases were excellent,28 cases were good,and 10 cases were still good,with a good rate of 87.5%．Conclusions , The selection of biological extended stem hemiarthroplasty for the treatment of unstable intertrochanteric fractures of the femur in elderly patients has the advantage of fast postoperative recovery,early weight bearing,reduced various complications of long-term bed rest,and achieved good joint function．