Minimally invasive intermuscular approach does not improve outcomes in bipolar hemiarthroplasty for femoral neck fracture.

Abstract

Minimally invasive surgery (MIS) can lead to early recovery, but its postoperative effect is short after total hip arthroplasty for osteoarthritis. Because bipolar hemiarthroplasty (BHA) for femoral neck fractures is preferred for elderly patients, early functional recovery may prevent the rapid progression of disuse atrophy, and an MIS surgical approach may improve subsequent hip joint function. MIS-BHA was performed using the direct anterior approach, without muscle or tendon detachment. A total of 83 patients who underwent BHA from April 2007 to February 2009 were assigned to MIS-BHA or conventional BHA. Selection of patients for MIS-BHA was not randomized. Hip joint function was evaluated with the Hospital for Special Surgery (HSS) system at 1 month and 1 year after surgery. There were no significant differences in age, sex, height, weight, body mass index, time from admission to surgery, or preinjury HSS scores between two groups. HSS scores were higher with MIS-BHA (24.2 vs. 20.2; P = 0.01) at 1 month but were similar 1 year after surgery (29.9 vs. 27.2; P = 0.10). The effectiveness of MIS-BHA for femoral neck fracture is limited to the early postoperative period. Therefore, MIS-BHA does not appear to be appropriate for treatment of femoral neck fractures.