Floating Shoulder Injury Resulting in Delayed Onset of Infraclavicular Brachial Plexus Palsy.

As the brachial plexus traverses the costoclavicular space, it is susceptible to compression by pathologies affecting the clavicle. Clavicle nonunions with hypertrophic callus may cause a delayed onset of brachial plexus palsy. We present a rare case of a floating shoulder injury causing medial and posterior cord brachial plexus palsy two months after initial injury. After the diagnosis was established, the patient was treated successfully with expeditious brachial plexus decompression, callus excision, and rigid osteosynthesis, with healing of the clavicle nonunion and scapular fracture, and recovery of sensory and motor deficits.