The use of dual-mobility components in total hip arthroplasty.

Dual-mobility hip components provide for an additional articular surface, with the goal of improving range of motion, jump distance (ie, vertical or inferior head displacement required for dislocation), and stability of the total hip arthroplasty. A large polyethylene head articulates with a polished metal acetabular component, and an additional smaller metal head is snap-fit within the polyethylene. New components have recently been released for use in North America. Although these devices are routinely used in some European centers for primary hip arthroplasty, their greatest utility may be to manage recurrent dislocation in the setting of revision hip arthroplasty. Several small retrospective series have shown satisfactory results for this indication at short- to midterm follow-up. Polyethylene wear and intraprosthetic dislocation are concerns, as is the lack of long-term data. Caution is thus advised in the routine use of dual-mobility components in primary and revision total hip arthroplasty.