Neuropathic upper extremity pain: A double-crush scenario

Neuropathic upper extremity pain has many causes. Cubital tunnel syndrome is the second most common compressive peripheral neuropathy after carpal tunnel syndrome. Entrapment, or compression, of the ulnar nerve at the elbow classically presents with elbow pain, numbness in the ulnar nerve distribution, and weakness in the hand. C8 radiculopathy and various brachial plexopathies can mimic cubital and carpal tunnel syndromes. Neoplastic brachial plexopathy typically is caused by local extension of a primary or metastatic tumor into the brachial plexus. Double-crush syndrome further complicates neuropathic upper extremity pain. This case report describes a patient with a double-crush lesion involving the ulnar nerve at the elbow and a metastatic mass involving the lower trunk of the brachial plexus. Because of overlapping symptoms and presentations of several upper extremity nerve conditions, clinicians must perform a thorough history and physical examination and understand the sensory and motor innervation of the upper extremity to arrive at a timely and accurate diagnosis.