Austin Moore hemiarthroplasty: technical aspects and their effects on outcome, in patients with fractures of the neck of femur.

In order to determine which technical aspects of the Austin Moore hemiarthroplasty procedure affect the outcome, we reviewed 243 patients with a non-pathological intracapsular femoral neck fracture who had, Austin Moore uncemented hemiarthroplasty. The immediate post-operative X-rays were assessed for alignment of the prosthetic stem, calcar seating, length of the neck remnant, leg length discrepancy and size of the head, compared with the contralateral femur. All patients were followed-up for 1 year. Significant pain at 1 year and/or revision of the prosthesis for loosening were considered as unfavourable outcomes. Inadequate calcar seating was significantly associated with pain and revision of the prosthesis (P = 0.04 and 0.01, respectively). Length of the neck remnant was also significantly associated with these two outcomes (P = 0.05 and 0.023, respectively). Difference in head size was associated with pain, but not with loosening (P = 0.01 and 0.08, respectively). The rest of the parameters were not significantly associated with the outcome. We recommend that when inserting an Austin Moore hemiarthroplasty, particular attention must be paid to the seating of the collar of the prosthesis on the calcar and correct choice of head size.