This syndrome is characterised by irritation of the ulnar nerve as it passes through a tunnel behind the elbow. The ulnar nerve is one the main nerves supplying sensation and strength to the forearm and hand. It passes relatively superficially over the elbow, making it prone to potential compromise at this point. This is the reason why leaning on your elbow for a prolonged period results in pins and needles in your forearm and hand. The nerve actually runs in a little groove just next to the “funny bone”.
Symptoms of compression of this nerve at this point are exactly the sort of symptoms that can happen if you lean on your elbow for too long. They consist of pain or sensory symptoms (numbness or pins and needles) radiating through your forearm and into your hand, particularly the ring and little fingers of your hand.
The reason people can develop compression of this is thickening of fibrous bands across the nerve or problems related to the elbow joint. The symptoms can often mimic compression of nerves higher up in the arm or the neck and this is the other diagnosis that will need to be excluded. Sometimes, the condition can be diagnosed purely from symptoms but carrying out nerve conduction studies will invariably make the diagnosis.
When symptoms are mild, this condition can simply be treated by avoidance of aggravating factors and attention to position of the elbow. However, if pain or sensory symptoms are severe, or if it interferes with the motor function of the nerve (there can be loss of strength or wasting of hand muscles), then surgery should be seriously considered.
The surgery entails decompressing the nerve by dividing the overlying fibrous bands to ensure that the nerve is free of compression. This can usually be successfully done under local anaesthetic and as a day case procedure. The incision is just forward of your “funny bone”. In the vast majority of people who undergo this surgery, it is very effective in relieving the pain and sensory symptoms. In early cases of motor loss, it can even reverse any weakness that has occurred. There is some tenderness around the operation site for a few weeks thereafter but a return to work is usually possible within 2 weeks of surgery.