Clavicle Fracture X-ray & CT Signs: Shoulder Injury Review

Clavicle fractures are classified by location: group I (midshaft, 80% of fractures), group II (distal third, 15%), and group III (medial third, 5%). Midshaft fractures are further described by Robinson's classification based on displacement and comminution. Distal clavicle fractures are subclassified by Neer type: type I (lateral to CC ligaments, stable), type II (medial to CC ligaments, unstable due to CC ligament disruption), and type III (intra-articular). Plain radiographs with AP and 15° cephalic tilt (Zanca view) for the AC joint are the primary imaging modality. CT adds value for complex fractures, medial physeal injuries in adolescents, and neurovascular evaluation. MRI is reserved for suspected concurrent soft-tissue shoulder injury.

Absolute indications for surgical fixation include open fractures, impending skin perforation, neurovascular compromise, and floating shoulder (concurrent ipsilateral clavicle and scapular neck fractures). Relative indications for operative treatment of displaced midshaft fractures include shortening greater than 15–20 mm, complete displacement (no cortical contact), comminution, and high-demand overhead athletes. Meta-analyses demonstrate higher union rates and faster return to activity with plate fixation compared to nonoperative management for displaced midshaft fractures, at the cost of hardware-related complications requiring plate removal in up to 30% of cases. Unstable Neer type II distal clavicle fractures with CC ligament disruption are reliably treated surgically given high nonunion rates with conservative care.

Nonunion occurs in approximately 1–5% of midshaft fractures treated conservatively, rising to 15% for displaced fractures with significant shortening. Symptomatic nonunion requires surgical debridement, plate fixation, and bone grafting. Malunion with clavicular shortening greater than 15 mm causes scapular protraction, altered glenohumeral biomechanics, and shoulder weakness. Post-traumatic thoracic outlet syndrome can arise from callus formation or malunion compressing the brachial plexus or subclavian vessels, producing neurogenic symptoms in the arm and hand. The axillary nerve and brachial plexus are at risk from fracture displacement or hematoma. Delayed AC joint arthritis may follow distal clavicle fractures that heal in malposition or with intra-articular extension.