Definition: chronic irritation of the ulnar nerve with sensory loss in the little finger side of the hand.
Ulnar nerve syndrome is caused by the entrapment of the nerve in the immediate proximity to the elbow joint. Because of its exposed location, the nerve is very prone to damage or entrapment, e.g. by repeated impact or as the result of work requiring the internal part of the elbow to be supported at all times.
The irritation of the nerve causes sensory disorders in the little finger side of the hand including the little finger itself (numbness). At a later date, this can lead to weakening of the intrinsic muscles of the hand, manifest in the inability to spread fingers forcefully or to contract them. This can be measured electrophysiologically by a neurologist.
Treatment of ulnar nerve syndrome
In the very early stages or in cases of very mild symptoms, resting the elbow or changing habitual movement patterns may calm the irritation. However, in most cases changes to the nerve are already so severe that surgical treatment is recommended. In this procedure, the nerve is taken out of the tunnel at the elbow and relocated in front of the epicondyle, thus placing it in a safer region. This type of surgery removes both the entrapment and the chronic irritation, thus establishing the preconditions for recovery of the nerve. In the post-operative period, unpleasant abnormal sensations (dysaesthesia) such as formication disappear quite quickly, but severe sensory disturbances or even muscular atrophies frequently take a very long time to recover. There is no guarantee of complete cure in these cases. As a rule of thumb, it can be assumed that the nerve has a recovery rate of about 1 mm a day from the site of its entrapment to the finger. For this reason, observations have shown that recovery periods for nerve function can take 1 to 2 years.