High variability in pelvic orientation in the lateral decubitus position negatively affects acetabular component...

Area of Science:

• Orthopedic Surgery
• Radiology
• Biomedical Engineering

Background:

• Acetabular component malposition is a significant concern in total hip arthroplasty (THA).
• Achieving proper intraoperative pelvic orientation (PPO) is essential for accurate component placement.
• The lateral decubitus position presents unique challenges for maintaining pelvic alignment.

Purpose of the Study:

• To identify factors associated with increased risk of acetabular component malposition in the lateral decubitus position during THA.
• To evaluate the impact of intraoperative pelvic orientation on acetabular abduction.
• To compare the effectiveness of different hip positioning systems in achieving PPO.

Main Methods:

• Retrospective review of 813 X-rays from posterior THA procedures.
• Measurement of pelvic tilt and rotation on preoperative and intraoperative X-rays.
• Assessment of acetabular abduction on postoperative X-rays.

Main Results:

• Proper intraoperative pelvic orientation (PPO) was achieved in 69% of cases.
• Shorter patients were more likely to achieve PPO (1.68m vs 1.72m).
• The Capello or Wixson hip positioner resulted in higher PPO rates (76%) compared to the De Mayo positioner (60%).
• PPO was associated with a higher rate of achieving goal acetabular abduction (88% vs 80%).

Conclusions:

• The use of specific hip positioning systems and patient height are significant factors influencing pelvic malpositioning during THA.
• Improper pelvic positioning negatively impacts acetabular component abduction.
• Optimizing intraoperative pelvic orientation is critical for successful THA outcomes.