CT of Acute Shoulder Girdle Fractures in Adults: Biomechanics, Classification, and Management.

The shoulder girdle, which includes the clavicle, scapula, and proximal humerus, forms a dynamic scaffold for seamless motion and load transfer to the axial skeleton. CT with multiplanar reformatted and volume-rendered images allows precise characterization, measurement, and injury classification and is particularly useful for complex high-energy disruptions encountered in trauma centers. The spectrum of shoulder girdle injuries spans clavicle fractures, acromioclavicular joint separations, floating shoulder patterns, glenohumeral fracture-dislocations, glenoid fossa fractures, proximal humerus fractures, and scapulothoracic dissociations. Most fractures are treated conservatively with sling immobilization, and absolute surgical indications are limited to open and impending open fractures or neurovascular compromise. However, since injury severity correlates with instability, chronic pain, and functional impairment, high-grade disruptions may warrant surgical intervention when specific criteria are met. Classification systems-such as the Neer, Rockwood, and Ideberg-Goss frameworks-combined with measurements including the glenopolar angle, glenoid index, glenoid track, and metaphyseal head extension inform the surgical risk-benefit calculus and help determine optimal surgical techniques and exposures. Radiologists can provide intuitive, salient reports and add value to surgical treatment planning discussions by synthesizing biomechanical first principles, grading systems, and key measurement parameters to arrive at the most feasible and likely surgical treatment options. ©RSNA, 2025 Supplemental material is available for this article.