Carpal tunnel syndrome
Carpal tunnel syndrome occurs when the median nerve, which runs from the forearm into the palm of the hand, becomes pressed or squeezed at the wrist. The median nerve controls sensations to the palm side of the thumb and fingers (although not the little finger), as well as impulses to some small muscles in the hand that allow the fingers and thumb to move. The carpal tunnel – a narrow, rigid passageway of ligament and bones at the base of the hand – houses the median nerve and tendons. Sometimes, thickening from irritated tendons or other swelling narrows the tunnel and causes the median nerve to be compressed.
Carpal Tunnel Syndrome – Symptoms
- Numbness or pain in your hand, forearm, or wrist that awakens you at night. (Shaking or moving your fingers may ease this numbness and pain.)
- Occasional tingling, numbness, “pins-and-needles” sensation, or pain. The feeling is similar to your hand “falling asleep.”
- Numbness or pain that gets worse while you are using your hand or wrist. You are most likely to feel it when you grip an object with your hand or bend (flex) your wrist.
- Occasional aching pain in your forearm between your elbow and wrist.
- Stiffness in your fingers when you get up in the morning.
With moderate or severe carpal tunnel symptoms, you may have numbness or reduced strength and grip in your fingers, thumb, or hand. It may be hard to:
- Do simple hand movements, such as brushing your hair or holding a fork. You may accidentally drop objects.
- Pinch an object between your thumb and first finger. (This is called loss of pinch strength.)
- Use your thumb while doing simple tasks such as opening a jar or using a screwdriver. With long-term carpal tunnel syndrome, the thumb muscles can get smaller and weaker (atrophy).
Symptoms most often occur in parts of the hand supplied by the median nerve: the thumb, the index finger, the middle finger, and half of the ring finger. The median nerve doesn’t affect your little finger. So if your little finger is affected, you may not have carpal tunnel syndrome.
Symptoms often occur in both hands, but they are usually worse in one hand than the other. You may first notice symptoms at night. People with carpal tunnel syndrome can usually fall asleep, but pain or numbness may wake them up.
Not all pain in the wrist or hand is caused by carpal tunnel syndrome. There are many other conditions with similar symptoms, such as:
- An injury to the muscles, ligaments, tendons, or bones.
- Nerve problems in the fingers, elbow, or neck.
- Arthritis in the thumb joint or wrist.