Cause of damage to the median nerve

The median nerve is a nerve that contains nerve fibers from the spinal cord segments C6 to Th1. It originates from the brachial plexus, a nerve plexus in the neck. If the nerve is damaged relatively high up in its course, the hand of oath occurs.

The cause of nerve paralysis can be in the area of the upper arm, e.g.B. in case of a humerus fracture (fracture of the humerus). Damage can also occur during sleep due to pressure from the humerus on the nerves.

This also applies to the area of the elbow. Traumatic causes such as fractures or cuts also play a role here. The median nerve can also be damaged in its further course along the forearm through the carpal tunnel.

In this case, however, the oath hand is no longer needed, because the nerve is already dividing at the forearm into a motor and sensitive branch. Only the sensitive branch passes through the carpal tunnel. Therefore, damage in the area of the forearm does not lead to a failure of the flexors of the thumb, index and middle finger. In this case, fist closure is possible without any problems.

The diagnosis of an oath hand

The diagnosis can be made relatively easily on the basis of various criteria. On the one hand, it is important to ask for some points (anamnesis): a hand of oath is always accompanied by sensitivity disorders. In addition to the hand of oath, there are other clinical signs that can be checked during the physical examination.

The bottle sign, for example, is positive. If a muscle on the thumb fails, a round vessel can no longer be completely enclosed. Also, pressing the fingertips of the thumb and little finger together usually does not work properly. In addition, there is always the apparative diagnostics like electroneurography and electromyography.

Is there evidence of damage to the median nerve in its course?
Are there any injuries or fractures in the area of the upper extremity?
Are there accompanying symptoms?