Which motions should be avoided immediately after hip arthroplasty?

• A. Abduction and external rotation
• B. Abduction and internal rotation
• C. Adduction and internal rotation
• D. Flexion beyond 90 degrees

Answer: (C)

After a hip arthroplasty, the joint is vulnerable to dislocation as healing tissues regain stability. Adduction moves the leg toward the midline, and internal rotation turns the thigh inward; when the hip is flexed, this combination places the prosthetic head at high risk of losing its position in the socket. Keeping the hip in neutral with slight abduction and external rotation helps protect the joint, and using an abduction pillow or avoiding crossing the legs reinforces this safety. So, avoiding movements that bring the leg together and twist it inward directly reduces dislocation risk, making adduction and internal rotation the motions to avoid immediately after surgery.