Also known as nerve entrapment, nerve compression occurs when repeated pressure on a nerve over a long period of time results in a breakdown of the blood-nerve barrier. This breakdown causes fluid to leak into the nerve, which leads to swelling, inflammation and scarring.
While many nerve compressions/entrapments go away on their own, some may produce debilitating, lasting symptoms. In these cases, surgical treatment may be considered.
Common Nerve Entrapment Syndromes:
- Carpal tunnel syndrome
Pressure on the median nerve, which runs the length of the arm and passes through the wrist, ending in the hand, can cause carpal tunnel syndrome. Symptoms of carpal tunnel syndrome include hand numbness, tingling and weakness.
- Cubital tunnel syndrome
Cubital tunnel syndrome is caused by increased pressure on the ulnar nerve at the elbow. The ulnar nerve passes through a bump on the bone on the inner portion of the elbow (the medial epicondyle) from the neck down into the hand.
- Tarsal tunnel syndrome
Tarsal tunnel syndrome is a painful condition in the foot caused by compression of the tibial nerve. Possible causes of tarsal tunnel syndrome include diabetes, arthritis, flat feet, fallen arches, enlarged tendons, or swelling from an ankle sprain.
- Thoracic outlet syndrome
A condition that affects nerves in the brachial plexus, and sometimes the adjacent artery and vein too. Symptoms include pain in the shoulder, chest and neck area that often radiates down into the arm and hand, particularly in the last two fingers. Therapy alone can sometimes relieve symptoms; however, cases that do not respond to therapy may require surgery. Possible causes of thoracic outlet syndrome include a congenital problem, disease, or injury (e.g., work-related repetitive strain activity, whiplash from a motor vehicle accident).
- Peroneal neuropathy (foot drop)
Occurs when the peroneal nerve (located in the leg below the knee) is injured or damaged. Injury to the peroneal nerve often leads to pain in the lateral leg or top of the foot, sometimes with tingling and numbness in these areas. As damage progresses, weakness of lifting the toes or ankle can be experienced as "slapping" of the foot when walking. Conditions that can cause a peroneal nerve injury include knee injury, surgery complication, or sometimes simply repetitive activity (e.g., running, prolonged squatting). Initially, this condition may be treated with physical therapy; depending on the cause and extent of injury, nerve decompression surgery may also be recommended.
In severe injuries, as may occur with trauma to the region of the knee, compete "foot drop" may occur where there is inability to lift the toes or foot at the ankle or turn the ankle out. In these cases, nerve grafting, nerve transfers or tendon transfers may be required.