Pinched nerve

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 disrupts the nerve’s function, causing pain, tingling, numbness or weakness.

A pinched nerve can occur at several sites in your body. A herniated disk in your lower spine, for example, may put pressure on a nerve root, causing pain that radiates down the back of your leg. Likewise, a pinched nerve in your wrist can lead to pain and numbness in your hand and fingers (carpal tunnel syndrome).

With rest and other conservative treatments, most people recover from a pinched nerve within a few days or weeks. Sometimes, surgery is needed to relieve pain from a pinched nerve.

CAUSES

A pinched nerve occurs when too much pressure (compression) 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 cause the condition.

In the case of carpal tunnel syndrome, a variety of tissues may be responsible for compression of the carpal tunnel’s median nerve, including swollen tendon sheaths within the tunnel, enlarged bone that narrows the tunnel, or a thickened and degenerated ligament.

A number of conditions may cause tissue to compress a nerve or nerves, including:

  • Injury
  • Poor posture
  • Rheumatoid or wrist arthritis
  • Stress from repetitive work
  • Hobbies or sports activities
  • Obesity

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 usually 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.



SYMPTOMS

Pinched nerve signs and symptoms include:

  • Numbness or decreased sensation in the area supplied by the nerve
  • Sharp, aching or burning pain, which may radiate outward
  • Tingling, “pins and needles” sensations (paresthesia)
  • Muscle weakness in the affected area
  • Frequent feeling that a foot or hand has “fallen asleep”

The problems related to a pinched nerve may be worse when you’re sleeping.

When to see a doctor

See your doctor if the signs and symptoms of a pinched nerve last for several days and don’t respond to self-care measures, such as rest and over-the-counter pain relievers.