From the Research
The average retroversion of the proximal humerus is approximately 21.11 degrees, as measured in a study of 180 Chinese individuals 1. This retroversion refers to the posterior angulation of the humeral head relative to the transepicondylar axis of the distal humerus. The degree of retroversion varies between individuals and can differ between dominant and non-dominant arms. Understanding normal humeral retroversion is clinically significant when evaluating shoulder pathologies, planning surgical interventions such as shoulder arthroplasty, and treating conditions like instability or impingement. Some studies suggest that the ideal retroversion angle for humeral component placement in shoulder arthroplasty may be around 20-30 degrees 2, 3, 4, but the most recent and highest quality study provides a mean retroversion of 21.11 degrees 1. It is essential to consider the individual variation in humeral retroversion to achieve optimal outcomes in shoulder surgery. Key points to consider include: