Your doctor may ask you questions and conduct one or more of the following tests to determine whether you have carpal tunnel syndrome:
- History of symptoms. Your doctor will review the pattern of your symptoms. For example, because the median nerve doesn’t provide sensation to your little finger, symptoms in that finger may indicate a problem other than carpal tunnel syndrome.
Carpal tunnel syndrome symptoms usually occur while holding a phone or a newspaper or gripping a steering wheel. They also tend to occur at night and may wake you during the night, or you may notice the numbness when you wake up in the morning.
- Physical examination. Your doctor will conduct a physical examination. He or she will test the feeling in your fingers and the strength of the muscles in your hand.
Bending the wrist, tapping on the nerve or simply pressing on the nerve can trigger symptoms in many people.
- X-ray. Some doctors recommend an X-ray of the affected wrist to exclude other causes of wrist pain, such as arthritis or a fracture. However, X-rays are not helpful in making a diagnosis of carpal tunnel syndrome.
- Electromyography. This test measures the tiny electrical discharges produced in muscles. During this test, your doctor inserts a thin-needle electrode into specific muscles to evaluate the electrical activity when muscles contract and rest. This test can identify damage to the muscles controlled by the median nerve, and also may rule out other conditions.
- Nerve conduction study. In a variation of electromyography, two electrodes are taped to your skin. A small shock is passed through the median nerve to see if electrical impulses are slowed in the carpal tunnel. This test may be used to diagnose your condition and rule out other conditions.