Dynamic stability during walking following unilateral total hip arthroplasty.

The purpose of this study was to examine dynamic stability, defined as the vertical projection of the center of mass (COM) to the base of support (BOS) mediolaterally during walking in 16 healthy and 16 unilateral total hip arthroplasty (THA) persons. There was a significant effect of side for double limb support (DLS) for the healthy group and between groups but not significant for single limb support. The dynamic stability pattern for the THA group was to hold the COM in the midline during a longer DLS phase demonstrating a different motor control strategy compared to healthy adults.