Carpal tunnel syndrome is a hand and arm condition caused by a pinched nerve in your wrist that produces numbness, tingling and weakness.
The carpal tunnel is a narrow passageway located on the palm side of your wrist that’s bound by bones and ligaments. This tunnel protects a main (median) nerve to your hand and the tendons that bend your fingers.
In general, anything that crowds irritates or compresses the median nerve in the carpal tunnel space can lead to carpal tunnel syndrome. Factors that can cause or increase your risk of carpal tunnel syndrome include:
- Injury. A wrist fracture or dislocation that alters the space within the carpal tunnel can create pressure on the median nerve.
- Nerve-damaging conditions. Some chronic illnesses, such as diabetes, increase your risk of nerve damage, including damage to the median nerve.
- Inflammatory conditions. Illnesses such as rheumatoid arthritis can affect the tendons in your wrist, exerting pressure on the median nerve.
- Imbalance in body fluids. Fluid retention, common during pregnancy or menopause, may increase the pressure within your carpal tunnel, irritating the median nerve.
- Workplace factors. The scientific evidence is conflicting but it’s possible that working with vibrating tools or performing a job that requires prolonged or repetitive flexing of the wrist may create pressure on or irritate the median nerve.
- Tingling or numbness. You may experience tingling and numbness — especially in your thumb and index, middle or ring fingers, but not in your little finger. This sensation may occur while holding a steering wheel, newspaper, or phone or while sleeping. It may extend from your wrist up to your arm.
- Weakness. You may experience weakness in your hand and find yourself frequently dropping objects. This may be due to the weakening of the thumb’s pinching muscles, which are controlled by the median nerve, or numbness in the hand.
Some people with mild symptoms can ease their discomfort by taking frequent breaks to rest their hands, avoiding activities that worsen symptoms and applying cold packs to reduce swelling.
If self-care techniques don’t offer relief, additional treatment options include wrist splinting, medications, and surgery.
- Wrist splinting. A splint that holds your wrist still while you sleep can help relieve nighttime symptoms of tingling and numbness.
- Nonsteroidal anti-inflammatory drugs (NSAIDs). These medications may help relieve pain associated with carpal tunnel syndrome.
- Corticosteroids. Your doctor may inject your carpal tunnel with a corticosteroid such as cortisone. Corticosteroids decrease inflammation and swelling, which relieves pressure on the median nerve.
- Surgery. The goal of carpal tunnel surgery is to relieve pressure on your median nerve by cutting the ligament that’s pressing on it. During the healing process after the surgery, the ligament tissues gradually grow back together while allowing more room for the nerve than existed before.
Excerpt From: The Mayo Clinic. “Mayo Clinic A to Z Health Guide”.