The association of dual-mobility total hip arthroplasty with dislocation compared to conventional hip arthroplasty for neck of femur fracture

Introduction Neck of femur fractures are extremely common worldwide and have a mortality rate of 15% at 1 year. Dual-mobility cups (DMCs) have demonstrated a reduction in dislocation and revision rates for elective total hip arthroplasty (THA) but the benefits of DMC use in neck of femur fractures are less clear. The aim of this study was to compare the rate of dislocation between conventional and DMC THA following neck of femur fracture. Materials and methods Data was retrospectively collected for patients who received either DMCs or standard acetabular components for neck of femur fractures at our institution. Patients were excluded if they had less than 2 years follow-up. Dislocation and revision rates were collected for all patients in addition to radiographic analysis to assess for loosening. Results Data was collected for 39 patients with DMCs and 95 patients with conventional THA. Two patients with DMCs suffered a dislocation (5.1%) compared to 7 patients (7.3%) who underwent a conventional THA (p = 0.49). Both patients in the DMC group had additional risk factors for dislocation. One DMC patient required revision surgery for dislocation and one conventional THA patient underwent a revision for aspetic loosening. There were no cases of radiographic loosening in the DMC group. Conclusions Our study showed a trend towards lower dislocation rates in patients treated with a DMC compared to conventional THA. Although there are potential issues associated with DMC implants and cost implications, this study suggests they may be advantageous in patients at high risk for dislocation.