Cubital Tunnel Syndrome
Compression of the ulnar nerve at the elbow, producing medial elbow pain, ulnar-sided hand paraesthesia, and eventually intrinsic weakness.
Overview
Cubital tunnel syndrome is the second most common upper limb compression neuropathy after carpal tunnel syndrome. The ulnar nerve is vulnerable to compression within the cubital tunnel by the arcuate ligament of Osborne, by traction with elbow flexion, and by dynamic subluxation over the medial epicondyle. Chronic compression leads to intraneural oedema, demyelination, and axonal loss.
Epidemiology
Annual incidence is around 25 per 100,000. Peak age is 40 to 60 years with a male predominance. Occupational and recreational activities that involve prolonged elbow flexion, leaning on the elbow, or repetitive throwing are risk factors.
Symptoms
Paraesthesia in the ulnar one and a half digits, medial elbow pain, and nocturnal symptoms worsened by elbow flexion. Weakness of grip and pinch, clawing of the ring and little fingers, and a positive Froment and Wartenberg sign develop in advanced disease. The elbow flexion and Tinel tests at the cubital tunnel are supportive.