Effect of Decubitus Position in Abducting the Hip on Function after Total Hip Replacement Arthroplasty

[Purpose] To show if the decubitus position in abducting the hip affects muscular strength, muscular activities and pain after total hip arthroplasty (THA). [Participants and Methods] The participants were 20 patients undergoing THA. They were assessed preoperatively, on postoperative day 3, and on postoperative day 10. Subjects quiescently abducted the opposite sides of the hip with maximum effort in the supine and prone positions. [Results] Muscular activities of tensor fasciae latae in abducting the hip were lower in the prone position than in the supine position. An interaction was recognized at the start time of gluteus medius activity in walking. On postoperative day 3, this time was later in both the supine and prone positions than preoperatively. On postoperative day 10, this time was earlier in the prone position than in the supine position. [Conclusion] The start time of gluteus medius activity in walking was later after THA than preoperatively, but abducting the hip in the prone position shortened this time more than in the supine position.