TITLE:
Do Femoral Neck and Stem Anteversion Affect Final Femur Rotation and Pelvic Positioning after Total Hip Arthroplasty?
AUTHORS:
Norio Imai, Tomoyuki Ito, Yasuhito Takahashi, Yoji Horigome, Ken Suda, Dai Miyasaka, Naoto Endo
KEYWORDS:
Anterior Pelvic Plane; Posterior Condylar Axis; Rotation; Total Hip Arthroplasty
JOURNAL NAME:
Open Journal of Orthopedics,
Vol.3 No.3,
July
12,
2013
ABSTRACT: In this study, we have investigated the rotation of the pre-operative and post-operative femur, and stem anteversion to prevent impingement and dislocation. We studied 126 patients who had undergone primary total hip arthroplasty (THA) for the treatment of osteoarthritis. We compared preoperative tilt of anterior pelvic plane (APP), posterior condylar axis of the femur (PCA) relative to APP (APP-PCA) with those of postoperative ones in supine position. There was a moderate correlation between the preand post-operative APP-PCA values (r = 0.71). The postoperative APP-PCA decreased by approximately 6°. However, there was poor correlation between the stem anteversion and the postoperative APP-PCA (r = －0.27). A greater reduction in APP-PCA was observed among patients who exhibited greater external rotation of femur compared to those who showed less external rotation in supine position before THA. We also observed that the post-operative rotation of the femur was dependent on the pre-operative rotation of the femur while it was independent of the stem anteversion.