Carpal tunnel syndrome occurs when the median nerve, which runs down the inside of your arm from your forearm to the palm of your hand, becomes compressed or pinched where it passes through your wrist.
At the wrist, your median nerve extends through the carpal tunnel, a narrow, rigid passageway of ligaments and bones that protects the nerve. The carpal tunnel also houses the tendons that help you bend and extend your fingers. When these tendons are irritated, swollen, or inflamed the tunnel becomes narrower and compresses the median nerve, causing the symptoms of CTS.
The first signs of CTS typically include intermittent tingling or numbness in your thumb, index, and middle fingers. You may also experience pain or discomfort in your wrist or through the palm of your hand. Common symptoms include:
As CTS worsens, you may experience numbness or tingling in your arm, wrist, hand, or fingers that wakes you up at night and makes you feel as if you need to “shake out” your hand. Left untreated, CTS can cause the muscles at the base of your thumb to waste away.
Women are more likely to develop CTS because, anatomically, they have smaller carpal tunnels. Any injury or condition that affects your wrist, including a bone fracture or arthritis, can also contribute to the development of CTS. Diabetes and other chronic illnesses that are associated with nerve damage can also lead to CTS.
Other significant risk factors include:
Treating CTS as early as possible is important in preventing long-term nerve damage. Initial treatment usually requires you to rest the affected hand for a couple of weeks, avoiding any activities that aggravate your symptoms. This includes wearing a wrist-hand orthotic, or splint, to immobilize your wrist and prevent further damage.
Changing patterns of hand use can also be helpful. Steroid injections may be beneficial if you have a significant amount of swelling around the median nerve, and over-the-counter pain relievers can help with any discomfort.
Severe cases of CTS may require surgery.