Ulnar nerve damage is damage to or dysfunction of the ulnar nerve, the long nerve in the arm that extends from the shoulder to the wrist. The ulnar nerve is susceptible to damage because it is close to the body’s surface, running along the exterior of the arm across the elbow. The ulnar nerve signals movement and sensation in the hand, supplying the fourth and fifth fingers.
To better understand the impact that the ulnar nerve can have on the entire arm, consider what happens when you hit your elbow on a hard surface. The funny bone, as it is sometimes called, is the place on your elbow where the ulnar nerve crosses and direct impact causes the arm to momentarily tingle painfully. When this happens, it is only mild acute trauma to the ulnar nerve, but serious impact or abuse can cause similar, yet chronic symptoms.
Damage to a single nerve or nerve group, such as the ulnar nerve, is referred to as mononeuropathy. Ulnar nerve damage can be the result of direct injury to the nerve or compression of the nerve caused by swelling, inflammation, or long-term pressure. The nerve damage may be immediate if there is trauma or injury such as a fracture or dislocation of the elbow, but often happens over time due to compression.
Symptoms of ulnar nerve damage or dysfunction include pain in the arm, especially the shoulder, tingling or numbness of the fourth and fifth finger, and weakness or loss of coordination in the hand. In some cases, ulnar nerve dysfunction occurs simultaneously with carpal tunnel syndrome and in cases of severe nerve damage the hand may appear deformed or claw-like.
Ulnar nerve damage is typically diagnosed by physical examination and review of symptoms as well as electromyography (EMG) and imaging tests. In mild to moderate cases, anti-inflammatory drug therapy, corticosteroid injections, and night splinting may relieve all symptoms. If symptoms do not improve or worsen, surgery to relieve pressure on the nerve may be required. Ulnar nerve transposition or anterior transposition of the ulnar nerve is an outpatient surgical procedure that repositions the nerve to relieve pressure and prevent permanent ulnar nerve damage.
Suspected damage or dysfunction of the ulnar nerve should be examined by an orthopedic doctor specializing in hand surgery. If the damage or injury is mild or moderate, the problem is likely to improve with non-surgical treatment. If left untreated, permanent nerve damage can occur, which could lead to permanent mobility and coordination problems.