Use of Dual Mobility Acetabular Component and Anterior Approach in Patients With Displaced Femoral Neck Fracture

Background: Although the antidislocation effect of total hip arthroplasty (THA) via the direct anterior approach (DAA) with dual mobility cup (DMC) for displaced femoral neck fracture (FNF) has already been reported, the clinical result of DMC-DAA-THA for displaced FNF in terms of mortality, complications, and walking ability are still unclear.

Methods: 106 cases with DMC-DAA-THA for displaced FNF were investigated of dislocation; perioperative complications; 3-, 6-, and12-month mortality rate; and pre/early postoperative walking ability. The walking ability was stratified into the following four categories: (1) use of a wheelchair (no walking), (2) walking alongside a support (including walkers designed for the elderly), (3) walking using one stick, and (4) unaided walking.

Results: There was no dislocation withing one-year postoperative. The 3-, 6-, and 12-month mortality rate was 2.8%, 4.7%, and 5.7%. Total complications occurred in 14 cases (14.7%). Although there was no revision surgery, two cases (1.9%) of intraoperative fracture treated without additional fixation, and one case of postoperative fracture was occurred. Among patients with preinjury walking category 2, 3, and 4 (total 94 cases), the number of patients who recovered same walking category at two-week postoperation was 56 cases (59.6%).

Conclusions: Our study demonstrated that DMC-DAA-THA for displaced FNF offered quick recovery of walking ability with no dislocation and low one-year mortality rate. We believe that the combination of early postoperative recovery due to the minimal invasiveness of the DAA and decreased dislocation rate due to increased range of motion by DMC and adequate soft tissue tension by DAA contributed to null dislocation.