Pinched Nerves
About pinched nerves
Pinched nerves involve damage or disruption to a nerve or group of nerves. This impairs the nerve’s function, causing symptoms such as tingling, burning pain, numbness or weakness. Many pinched nerves are a form of radiculopathy, which is a disorder of the spinal nerve roots, but they can occur elsewhere, such as carpal tunnel syndrome in the wrist.
In some cases, the damage of a pinched nerve results from nearby tissue applying too much pressure on a nerve. Constriction or stretching can also cause a pinched nerve.
Nerves are a network of “wires” throughout the body that carry information to and from the brain and spinal cord. Pinched nerves often involve pressure from a ligament or a tendon on a bone. Nerves can also be compressed by other structures, such as a herniated disc or a tumor.
Injury to a nerve can slow or stop signals from traveling to and from the brain and spinal cord. This often causes weakness of muscles, and some patients may lose feeling in the injured area or experience burning or “pins and needles” sensations (paresthesia).
Pinched nerves that last for a short period of time usually cause no permanent damage. However, an untreated pinched nerve can result in permanent damage and may result in permanent weakness and chronic pain.
Risk factors and potential causes of pinched nerves
Pinched nerves often occur when a nerve is compressed between a ligament or tendon and a bone. Overuse of certain parts of the body can cause a pinched nerve. For instance, long periods working on an assembly line, at a keyboard or at other repetitive tasks can cause a repetitive stress injury. A familiar, minor example of a pinched nerve is a foot or arm “falling asleep” because of temporary pressure on a nerve serving the affected limb.
Conditions associated with pinched nerves include:
- Carpal tunnel syndrome. Compression of the median nerve in the carpal tunnel of the wrist. Hand and wrist pain, numbness and tingling typically result.
- Tennis elbow (lateral epicondylitis). An injury to the outer elbow that affects the area where the tendons of the forearm muscles attach to the bony prominence on the outside of the elbow. Pain can also spread into the forearm and wrist.
- Golfer elbow (medial epicondylitis). Like tennis elbow, this is a form of tendinitis caused by overuse but affects the inner elbow.
- Ulnar nerve entrapment. Compression of the ulnar nerve in the arm, most often in the cubital tunnel of the elbow (cubital tunnel syndrome). Injury of the ulnar nerve may be due to sudden or repetitive trauma.
- Subscapular nerve entrapment. Shoulder pain caused by impingement of the subscapular nerve.
- Tarsal tunnel syndrome. Foot pain caused by impingement of the tibial nerve.
- Sciatica. Can result when a herniated disc in the lower spine presses on a nerve root, causing pain that radiates down the back of the leg.
- Compression of a spinal nerve. Restriction of nerves as they leave the spine. This compression can be due to spinal stenosis (narrowing of space inside the spinal column), to bone spurs formed from spinal arthritis or to a ruptured disc.
- Peripheral neuropathy. A disease or degenerative state of the nerves. Failure to treat pinched nerves may result in chronic neuropathy.
- Tumor. Malignant (cancer) or benign tumors can compress nerves.
- Use of crutches. These can constrict nerves in the axillary (armpit) region.
- Scar tissue resulting from previous surgery.
- Excessive swelling in soft tissues (e.g., after injury). Rarely, this can cause pressure on a nerve.
Signs and symptoms of pinched nerves
Pinched nerves often cause the sensation of a hand or foot “falling asleep,” which is often described as numbness, tingling or “pins and needles” sensations (paresthesia). Other typical symptoms include:
- Pain
- Muscle weakness
- Muscle spasms
- Gait disturbances
Diagnosis and treatment of pinched nerves
Diagnosis of a pinched nerve begins with a medical history and a physical examination. Imaging and nerve tests may help reveal the nature of the compression on the nerve.
These tests include:
- X-rays. Use low doses of radiation to produce images on film or fluorescent screens.
- CAT scan (computed axial tomography). Uses multiple x–rays to create cross–sectional images of the body.
- MRI (magnetic resonance imaging). Uses powerful magnets to produce images on a computer screen and film.
- Electromyography (EMG). The most important diagnostic test for a pinched nerve, where individual nerves and muscles are assessed with electrodes placed on the skin or thin needles inserted into muscle.
Treatment of pinched nerves is focused on freeing the nerve from compression. Rest is the chief treatment, with the goal of shrinking the swollen tissue around the nerve. Medications such as corticosteroids may also be used to alleviate inflammation and Pain. Injection of steroids around the swollen nerve is a very common treatment done by pain specialists. Acupuncture may be used to treat some pinched nerves. Most pinched nerves resolve within a few days or weeks.
In some cases, surgery may be necessary. For example, it can remove scar tissue that may have built up around the nerve due to chronic swelling and tenderness. Spinal surgery can remove an intervertebral disc or bone spurs pressing on the nerve, and carpal tunnel release can relieve pressure on the median nerve of the wrist.
Other treatments may include:
- Avoiding activities that cause symptoms.
- Physical therapy, manipulation therapy or occupational therapy.
- Splints, braces or other types of support.
- Modalities (physical agents) such as thermotherapy to reduce pain. However, impairment of sensation may rule out use of thermal treatments because of risks such as burns.
Questions for your doctor on pinched nerves
Preparing questions in advance can help patients to have more meaningful discussions with their physicians regarding their conditions. Patients may wish to ask their doctor the following questions about pinched nerves:
- What is a pinched nerve? How can I recognize one?
- What else might be causing my symptoms?
- Which of my conditions are associated with pinched nerves?
- What tests might I need to reveal a pinched nerve?
- What do my test results show? What exactly is causing my pinched nerve?
- Can medications and rest relieve my pinched nerve? Can exercise or physical therapy help me?
- Can a splint or other device give me relief?
- Can the underlying cause of my pinched nerve be addressed?
- Could I need surgery if conservative treatments fail?
- What could happen if I leave a pinched nerve untreated?