Bipolar hemiarthroplasty using microarc oxidation-coated cementless stem in patients with unstable intertrochanteric fracture

Abstract

Purpose: Treatment for an unstable intertrochanteric fracture in elderly patients is challenging. Bipolar hemiarthroplasty (HA) using microarc oxidation (MAO) coating has been a treatment option alternative to internal fixation. However, the outcome of bipolar HA using MAO-coated stem in these patients is unknown. Methods: From July 2007 to April 2016, 234 (older than 65 years) patients (234 hips) who were diagnosed as having unstable intertrochanteric fractures were treated with bipolar HA using a fully MAO-coated standard-length rectangular cementless stem. During the arthroplasty, the greater trochanteric and the medial fracture fragments were attached to the stem and fixed with two to three 16-gauge wires. Forty-eight patients (48 hips) died within postoperative 2 years. The remaining 186 patients (186 hips) were followed up for a mean of 4.3 (range 2–10) years. Results: With the exception of 4 patients who died during hospitalization, 176 of 230 ( 76.5%) patients could ambulate independently with or without an assistive device at the time of hospital discharge. Venous thromboembolism occurred in seven patients (3.0%). One hip dislocated due to a fall 1 month after the arthroplasty. Periprosthetic femoral fracture occurred in four patients and periprosthetic acetabular fracture in one patient. One patient had periprosthetic of acute pyelonephritis. There was no focal osteolysis around the femoral stem. Conclusion: The result of cementless HA using MAO-coated stem enabled early ambulation in most (76.5%) of elderly patients with unstable intertrochanteric fractures and the results were encouraging.