Guyon’s syndrome in cyclists
I often come across ulnar nerve entrapment at the wrist in cyclists. The nerve is entrapped in the Guyon canal which can be found in the medial internal part of the wrist. At the end of this canal the ulnar nerve branches out. One branch provides innervation of the muscles of the hand and the other branch regulates the sensitivity of the small finger and the ring finger.
The frequency of this injury depends on the position on the bike and whether the hands are on the handlebars for many hours during training or races. The hands are constantly under stress because of vibrations caused by riding over bumpy roads causing contusion, compression and traction of the ulnar nerve. Symptoms are easy to recognize and consist of a sort of loss of sensitivity of the areas which are controlled by the ulnar nerve. The loss of sensitivity often involves the fourth and fifth finger of the hand and can cause hypotrophy of the hypothenar eminence muscles in the inner part of the hand.
This injury is often found in persons who cycle without gloves with good padding. To prevent these problems and this kind of pain it is important to make sure you assume the correct position on your bike. The saddle and handlebars need to be regulated correctly to force the back into a correct position that allows the weight of the body and the stress on the wrists to be offloaded efficiently.
Once this painful pathology manifests itself, it is not difficult to treat. Among the most frequent treatments are the use of anti-inflammatory drugs, laser and ultrasound, or manipulation or similar conservative interventions. Cases that require surgical intervention are rare and can be carried out in a day hospital.