The ulnar nerve is one that we all become aware of at some point in our lives when we hit our 'funny bone'. Most nerves within the body are protected from being hit like this because they are nestled between muscles and bone, but the ulnar nerve is not.

When we hit the ulnar nerve, we can temporarily trap it beside the large forearm bone (known as the ulna). The symptoms we experience for the 20 to 30 seconds afterwards are almost exactly the same as experienced in ulnar nerve entrapment, although as time goes on and the nerve remains trapped these symptoms become progressively worse. We first experience numbness in our ring and little finger. This is because the ulnar nerve is connected directly to these fingers, with no other nerves serving them. Because the nerve is compressed the signals of sensation the nerve picks up get blocked and cannot travel back to the brain for processing.

Of course, the symptoms of ulnar nerve entrapment largely depend on where the nerve is trapped. This doesn't just happen at the elbow, but can happen anywhere from the brachial plexus (a bundle of nerves in the shoulder) right down to the wrist. When ulnar nerve entrapment happens at the wrists it usually causes the two fingers to curl up; you can simulate this by letting your hand go limp and putting pressure on the underside of your arm, about 3 or four inches below the wrist. The curling is usually indicative of long term damage which may be irreversible, which is why people suffering with ulnar nerve compression of any kind should seek medical attention as soon as they experience numbness in the ring and little finger lasting more than 24 hours.

Treatments for ulnar nerve entrapment are varied. They can go from simply waiting until it eases and avoiding repetitive tasks using that limb, to surgery. Treatment of this condition, however, usually depends entirely upon what has caused the condition in the first place. If it's an abnormality in the wrist, elbow or brachial plexus then physiotherapy or surgery may be required. If, on the other hand it's being caused by thrombosis, alcoholism or diabetes then these need to be treated urgently to stop such drastic physiological changes occurring. Apart from banging the 'funny bone', pregnancy is the only other example of ulnar nerve entrapment that is both temporary and harmless to the individual. Do note that this condition rarely happen by itself and is instead indicative of an underlying problem elsewhere in the body.

Ulnar nerve entrapment itself will not cause any other conditions in the body apart from the death of the nerve and the inability to use the ring finger and little finger of the hand. However, this can severely impair quality of life and anyone who thinks they may be suffering with this condition should visit their doctor as soon as possible. When it comes to dealing with trapped nerves, an early diagnosis gives a much better chance of simple, quick and painless treatment.

Stan Tian

Copyrighted material; do not reprint without permission.

 

View all articles by Stan Tian