Traumatic Shoulder Injuries: A Force Mechanism Analysis of Complex Injuries to the Shoulder Girdle and Proximal Humerus

OBJECTIVE: Acute shoulder trauma can result in complex injuries to the bone and soft-tissue structures of the shoulder girdle with the associated risk of development of shoulder girdle instability. Destabilizing injuries to the shoulder girdle and fractures of the proximal humerus can occur in predictable patterns based on the injury mechanism. The objectives of this article are to illustrate the relevant anatomy of the shoulder, use 3D modeling and animation to aid in a mechanistic understanding of some of the most common injury patterns, discuss the most relevant radiologic findings that determine the ultimate treatment approach, and discuss an approach to imaging diagnosis with attention to the common treatment strategies. CONCLUSION: Understanding the force mechanisms responsible for the most common patterns of traumatic shoulder girdle injuries and proximal humeral fractures can improve detection of associated clinically significant secondary injuries, increase the effectiveness of injury classification, and ultimately direct appropriate and timely intervention.