Anatomical variability of the shoulder region: morphological insights and clinical relevance

Abstract

The shoulder represents one of the most anatomically complex and mobile joints in the human body, requiring a deep understanding of its normal structure and numerous anatomical variants for safe and effective surgical intervention. While frequently considered as normal, these entities yield a significant clinical and imaging relevance. This paper aims to synthesize current knowledge on common and rare anatomical variants of the shoulder joint, with a focus on the glenoid labrum (such as sublabral recess, sublabral foramen, and Buford complex), posttraumatic labral lesions (Superior Labrum from Anterior to Posterior tear, Bankart lesion), acromial morphology, and acromial ossification anomalies. The analysis relied on systematic cadaveric dissections, imaging studies, and clinical correlations and aims to provide a comprehensive overview of structural deviations that may influence diagnosis, surgical planning, and treatment outcomes. In this paper, we will highlight key anatomical variants, their imaging features and clinical relevance. Differential diagnosis is addressed, alongside the relevance of these variants in the context of magnetic resonance imaging and arthroscopy. The results emphasize the necessity of a strong knowledge of these entities in avoiding wrong imaging interpretation and optimizing surgical planning. This study underlines the importance of recognizing and understanding anatomical variants not as anomalies, but as clinically significant features that should be anticipated and addressed, particularly in orthopedic surgery, sports medicine, and anatomical education.