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Carpal Tunnel Syndrome

What Is Carpal Tunnel Syndrome?

Carpal tunnel syndrome results when the median nerve at the wrist is compressed by surrounding tissue or excess fluid. The carpal tunnel is the passageway, composed of bone and ligament, through which a major nerve system of the forearm passes into the hand. These nerves control the muscles in this area, as well as the nine tendons that allow your fingers to flex.

The wear and tear of repeated movement thickens the lubricating membrane of the tendons and presses the nerves against the hard bone. This process, call nerve entrapment, can be caused not only by repetitive strain, but also by bone dislocation or fracture, arthritis, and fluid retention—anything that narrows the tunnel and compresses the nerve.

Who Gets Carpal Tunnel Syndrome?

The disorder occurs most often among women between the ages of 30 and 60. The condition is often occupation-related; it develop in people who regularly use vibrating machinery and tools, such as construction workers, carpenters, and dentists, and people who use their wrists repetitively, including anyone who works at a computer for extended periods of time.  People who regularly drive long hours are also susceptible, as are those  who frequently engage in hobbies such as tennis, rowing, knitting, needlepoint, and gardening may also be at an increased risk for carpal tunnel syndrome.


  • Numbness or tingling in hand and wrist area. Symptoms may first occur early in the morning or at night.
  • Pain in the hand, wrist, or arm, may appear suddenly or gradually and often affect both hands.
  • Impaired reflexes.
  • In advanced cases of carpal tunnel syndrome, shrinkage or atrophy of the fleshy area at the base of the thumb may occur.

Causes/Risk Factors

The primary risk factor for carpal tunnel syndrome is a history of another musculoskeletal disorder, as well as long-term repetitive work involving the hands, wrists, and arms. Other risk factors include underlying medical conditions, such as arthritis, diabetes, reduced thyroid gland function (hypothyroidism), hormonal changes due to pregnancy or birth control pills, tendon inflammation, wrist fracture.

What If You Do Nothing?

Milder cases of carpal tunnel syndrome can sometimes disappear without treatment. But usually symptoms will progress and worsen if you do nothing to alleviate the problems. Symptoms may improve with home remedies, such as rest, ice packs, over-the-counter pain relievers, and making ergonomic adjustments, such as repositioning a computer keyboard, to reduce further stress to the hand and wrist. If symptoms persist despite treatment, damage to the median nerve can become more severe and ultimately impair daily function. Before this happens, get medical advice.


  • A health care professional will take a full medical history and conduct a physical examination.
  • Imaging tests, such as x-rays, may be required to view damage to the hands and wrists.
  • A nerve conduction velocity study may be used to monitor the electrical impulses along the median nerve to determine if it is compressed.


  • Rest is often prescribed for milder cases of carpal tunnel syndrome. Elevating the arms above the head using pillows may also reduce swelling.
  • Ice packs applied to the wrist for about 20 minutes may help reduce swelling.
  • Talk to your doctor about stretching and strengthening exercises to strengthen the fingers, hands, wrists, forearms, shoulders and neck and improve blood flow. This may also help prevent further damage to the hand and wrist.
  • Over-the-counter analgesic such as acetaminophen or ibuprofen can be used for pain.
  • A wrist splint that keeps your wrist and fingers in a neutral position may be prescribed to help ward off pain at night; it keeps you from bending your wrist in your sleep. Other devices, such as therapeutic fingerless gloves and wrist trolleys, have not been clinically proven to be effective.
  • Diuretics may be prescribed to reduce fluid accumulation in swollen tissue.
  • Corticosteroids injections can reduce inflammation.
  • If nerve injury or muscle damage progresses, surgery to relieve pressure on the median nerve may prove advisable. Surgery is often successful in restoring full hand function.


  • Don’t flex your wrists. When you bend and twist your wrists at awkward angles, it puts pressure on the median nerve. Keep your wrists straight while doing tasks such as cutting up meat and vegetables, washing dishes or using a hammer.
  • Avoid twisting off lids using only your thumb, index finger and middle finger because it increases pressure in the wrist. Also, lift objects with whole hand—or with both hands—to reduce stress on the wrist. And we’re not just talking about boxes. Don’t overload your hands with shopping bags.
  • Adjust your keyboard. Many of us spend several hours at a computer keyboard. To reduce the risk of carpal tunnel syndrome, be sure your fingers are lower than your wrists when typing. Avoid resting the heels of your hands on the keyboard because it forces your hands to bend backwards. Don’t pound the keys on your keyboard since it aggravates the median nerve in your wrists.
  • Take frequent breaks when engaged in activities requiring repetitive hand motions.
  • Hold your car’s steering wheel gently to reduce pressure on your wrists. Prolonged intense gripping irritates the wrist.
  • If you find that you’re flexing your hands too much, talk to your doctor about the benefits of wearing hand splints at night.

When to Call A Doctor

Call a doctor if symptoms of carpal tunnel syndrome become sufficiently troublesome or begin

to interfere with normal daily activity.

Reviewed by Diane M. Horowitz, M.D., Rheumatologist, North Shore Long Island Jewish Health System, Great Neck, NY. Review provided by VeriMed Healthcare Network.