Neuropathy, Axillary

The axillary nerve is primarily a motor nerve carrying C5-C6 fibers from the upper trunk of the brachial plexus to supply the deltoid and teres minor muscles. Axillary neuropathy is a complication of shoulder dislocation and manifests as shoulder pain and impaired arm abduction due to deltoid muscle weakness. Axillary neuropathy may occur with brachial plexopathy from any cause including the idiopathic condition known as neuralgic amyotrophy. Electromyography studies help to differentiate axillary neuropathy from other conditions causing shoulder pain and weakness. A frozen shoulder (adhesive capsulitis) may complicate axillary neuropathy due to loss of arm abduction.