What is the average humeral retroversion reproduced during shoulder arthroplasty?

What is the average humeral retroversion reproduced during shoulder arthroplasty?

• A. 20 degrees
• B. 25 degrees
• C. 30 degrees
• D. 40 degrees

Answer: (C)

Reproducing the native twist of the humeral head relative to the shaft is essential for restoring normal shoulder mechanics after arthroplasty. In most people, the humeral head sits retroverted by about 25 to 30 degrees. Clinically, aiming for roughly 30 degrees of retroversion when placing the humeral component gives a good match to average anatomy and supports balanced motion. Too little retroversion can limit external rotation and risk posterior impingement; too much can predispose to instability and abnormal joint kinematics. Therefore, about 30 degrees is the standard target to reproduce the native alignment.

Reproducing the native twist of the humeral head relative to the shaft is essential for restoring normal shoulder mechanics after arthroplasty. In most people, the humeral head sits retroverted by about 25 to 30 degrees. Clinically, aiming for roughly 30 degrees of retroversion when placing the humeral component gives a good match to average anatomy and supports balanced motion. Too little retroversion can limit external rotation and risk posterior impingement; too much can predispose to instability and abnormal joint kinematics. Therefore, about 30 degrees is the standard target to reproduce the native alignment.