Ulnar nerve dysfunction

Definition

Ulnar nerve dysfunction is a problem with the nerve that travels from the wrist to the shoulder. The condition causes movement or sensation problems in the wrist and hand.

Alternative Names

Causes

Ulnar nerve dysfunction is a common form of peripheral neuropathy. It occurs when there is damage to the ulnar nerve, which travels down the arm. The ulnar nerve is near the surface of the body where it crosses the elbow, so prolonged pressure on the elbow may cause damage. The damage involves the destruction of the covering of the nerve ( myelin sheath) or part of the nerve (axon). This damage slows or prevents nerve signaling.

A problem with one single nerve group (such as the ulnar nerve) is called mononeuropathy. The usual causes are direct injury, prolonged external pressure on the nerve, or compression of the nerve caused by swelling or injury of nearby body structures. Entrapment involves pressure on the nerve where it passes through a narrow structure.

The ulnar nerve is commonly injured at the elbow because of elbow fracture or dislocation. Prolonged pressure on the base of the palm may also cause damage to part of the ulnar nerve. In some cases, no detectable cause can be identified.