Injury to the median nerve at the elbow may cause symptoms to appear in the forearm, wrist and hand.
Symptoms of a median nerve injury
An injury above the elbow may result in difficulty or even inability to turn the hand over or flex the wrist down. Injuries below this may cause tingling or numbness in the forearm, thumb and the three adjacent fingers. Weakness with gripping and inability to move the thumb across the palm may also be experienced along with wasting of the muscles at the base of the thumb.
Median nerve injury explained
The median nerve can be torn partially or fully or compressed at the elbow. This can be from a fracture or other traumatic injury, or compression from excess fluid build up following an injury.
The median nerve emerges from the neck at the brachial plexus between the 5th cervical (neck) and 1th Thoracic (upper back) vertebrae. It then passes down the arm, past the elbow and splits into branches which serve the thumb and three fingers (missing just the little, pinky finger!).
At the elbow, the nerve passes to the inner side of the joint and so injuries in this area are most at risk of causing median nerve injury. It also runs alongside the brachial artery and so an acute injury to the median nerve may also cause injury to this major blood vessel.
Injuries such as a supracondylar fracture, elbow dislocation or any form of fracture should be examined for damage to the median nerve. Even relatively minor injuries, to the medial ligament for example, may result in median nerve symptoms due to increased pressure on the nerve from bleeding and swelling in the area.
Injuries to the median nerve at the elbow are either lesions - where the nerve is torn either partially or fully, or compressed due to displacement of a fracture or excess fluid following injury. Lesions are more serious, long-term injuries. Compression injuries usually resolve when swelling dissipates or when a displaced fragment of bone is removed.
The most common injury involving the median nerve is Carpal Tunnel Syndrome. However this is caused by a decrease in space at the carpal tunnel in the wrist and so would not occur as a result of an elbow injury. Pronator Teres Syndrome is another entrapment neuropathy of the median nerve, this time as it passes between the two heads of the pronator teres muscle.
As median nerve injuries at the elbow are usually caused by another acute injury, the priority is to treat the initial injury. This may be a fracture or dislocation or a soft tissue injury. But in many cases, treating the offending injury, eases the median nerve symptoms.
Applying ice, compression and elevation to a soft tissue injury will help to reduce swelling, in turn reducing pressure on the median nerve. A displaced fracture at the elbow, which is compressing the median nerve may also be corrected by surgery to remove or realign the fragment, again easing pressure on the nerve.
Median nerve symptoms may clear up very quickly if no long term damage was sustained. However, if the nerve was damaged, the symptoms listed above may be more long-lasting.