Definition
A pinched nerve occurs when too much pressure is applied to a nerve by surrounding tissues — such as bones, cartilage, muscles or tendons. This pressure (compression) disrupts the nerve's function, causing pain, tingling, numbness or weakness in the affected area.
A pinched nerve can occur anywhere in your body. For example, a herniated disk in your lower spine may put pressure on a nerve root, causing pain that radiates down the back of your leg (sciatica). Another common type of pinched nerve is the median nerve in the carpal tunnel in your wrist; compression of that nerve can lead to pain and numbness in your hand and fingers (carpal tunnel syndrome). These are just two common examples of pinched nerves; many other nerves can be pinched — including those in your neck, shoulder, elbow and other areas.
With rest and other conservative treatments, most people recover from a pinched nerve within a few days or weeks. In some cases, however, surgery is necessary.
Causes
A pinched nerve occurs when too much pressure is applied to a nerve by surrounding tissues. In some cases, this tissue might be bone or cartilage — such as in the case of a herniated spinal disk that compresses a nerve root. In other cases, muscle or tendons may be the culprits. In the case of carpal tunnel syndrome, a variety of tissues may be responsible for compression of the carpal tunnel's median nerve, including swelling of tendon sheaths within the tunnel, narrowing of the tunnel by bone enlargement, or thickening and degeneration of a ligament.
A number of conditions may cause these tissues to compress a nerve or nerves. Injury, poor posture, osteoarthritis, stress from repetitive job, hobby or sports activities, and obesity are common causes of nerve pressure.
This pressure causes inflammation of the nerve and disrupts the nerve's function. If a nerve is pinched for only a short time, there's typically no permanent damage. Once the pressure is relieved, nerve function returns to normal. However, if the pressure continues, chronic pain and permanent nerve damage can occur.
Risk factors
The following factors may increase your risk of experiencing a pinched nerve:
Posture. Poor posture adds pressure to your spine and nerves.
Osteoarthritis. Nerves can become pinched in the bone spurs caused by osteoarthritis.
Overuse. Jobs or hobbies that require repetitive hand, wrist or shoulder movements, such as assembly line work, increase your likelihood of a pinched nerve.
Obesity. Excess weight can add pressure to nerves.
Heredity. Some people appear to be genetically predisposed to conditions that lead to pinched nerves.
Tests and diagnosis Nerve conduction study. Patch-style electrodes are placed on your skin to stimulate the nerve with a mild electrical impulse. You will feel a sensation like an electric shock, which may be uncomfortable. Test results tell your doctor whether you have a damaged nerve. This test may also be called a nerve conduction velocity test.
Electromyography. This test measures the electrical discharges produced in muscles. During the test, a thin needle electrode is placed into the muscle to record electrical activity. You will be asked to rest and contract the muscle, such as by bending your arm. You may feel pain when the needle is inserted, and your muscle may be sore for a few days after the test. Test results tell your doctor if there's damage to the nerves leading to the muscle.
Rarely, doctors use magnetic resonance imaging (MRI) to confirm the diagnosis. MRI is a technique that uses a magnetic field and radio waves to create cross-sectional images of your head and body.
Treatments and drugs
The most frequently recommended treatment for pinched nerve is rest for the affected area. Your doctor will ask you to stop any activities that cause or aggravate the compression.
Depending on the location of the pinched nerve, you may need a splint or brace to immobilize the area. If you have carpal tunnel syndrome, your doctor may recommend wearing a splint at night as well as during the day because wrists flex and extend frequently during sleep.
Physical therapy
A physical therapist can teach you exercises that strengthen and stretch the muscles in the affected area in order to relieve pressure on the nerve. He or she may also recommend modifications to activities that aggravate the nerve.
Medications
Nonsteroidal anti-inflammatory drugs (NSAIDs) such as ibuprofen (Advil, Motrin, others) and naproxen (Aleve, Naprosyn) can help relieve pain and alleviate inflammation around the nerve. Your doctor may recommend a prescription-strength NSAID if your pain is severe.
Corticosteroid injections into the affected area can help minimize pain and inflammation.
Surgery
If the pinched nerve doesn't improve after several weeks to a few months with conservative treatments, surgery to take pressure off the nerve may be necessary. The type of surgery varies depending on the location of the pinched nerve. Surgery may entail removing bone spurs or a herniated disk in the spine, for example, or severing the carpal ligament to allow more room for the nerve to pass through the wrist.
Prevention
The following measures may help you prevent a pinched nerve:
Maintain good posture.
Incorporate strength and flexibility exercises into your regular exercise program.
Limit repetitive activities, and take frequent breaks when engaging in these activities.
Maintain a healthy weight.
