Analysis of implants for metastatic bone tumors of the proximal femur: A retrospective study.

Abstract

To investigate the relationship between surgical techniques used in our hospital to treat metastatic bone tumors of the proximal femur and activity level and prognosis of patients and whether the location of the tumor is considered when selecting surgical techniques. We retrospectively reviewed 82 patients with metastatic bone tumors of the proximal femur who underwent intramedullary nail fixation (IMN), bipolar hip arthroplasty (BHP) or modular megaprosthesis (MMP) in our hospital from 2007 to 2020. We measured the distance from the center of femoral head to the proximal (x) and distal (y) end of the of tumor, using preoperative computed tomography images to determine the location of metastasis. We also measured revised Katagiri score at the time of fracture, postoperative ISOLS/MSTS (functional outcome) scores, and overall survival. The value of x was significantly different among the three groups. The value of y showed a significant difference between the IMN and BHP groups and the BHP and MMP groups. The functional outcome score was significantly lower in the IMN group. The survival rate of the patient tended to be higher in the BHP and MMP groups than in the IMN group 1 year postoperatively. IMN was favored when the distance from the center of femoral head to the proximal end of the tumor was ≥15mm. In the case of prosthetic replacement, BHP was chosen if the distance from the center of femoral head to the distal end of the tumor was ≤70mm. BHP and MMP were preferred over IMN functionally.