Carpal tunnel syndrome is usually diagnosed using:
Medical history. The doctor will ask about any medical problems or illnesses, prior injuries, current symptoms, or daily activities that may be causing your symptoms.
Hand diagram. You may be asked to help fill in a diagram of your hand to show where you have numbness, tingling, or pain.
Physical exam, including comparing the strength of both hands.
If your symptoms are severe, if nonsurgical treatment has not improved symptoms, or if your symptoms aren’t clearly caused by carpal tunnel syndrome, your doctor may recommend:
Nerve testing, which checks the median nerve.
X-rays. These can check for bone problems caused by past injury, arthritis, recently broken or dislocated bones, or tumors. X-rays aren’t used to diagnose carpal tunnel syndrome. But they can be helpful for finding signs of arthritis or an old or new wrist or neck injury that may be adding to your symptoms.
Ultrasound, to look at the size of the median nerve. It is inexpensive, comfortable, and quick. But its use for carpal tunnel syndrome diagnosis is still unproven and fairly uncommon.
MRI. This imaging test can find swelling of the median nerve, narrowing of the carpal tunnel, or problems with circulation of blood through the carpal tunnel.
Blood tests. These are sometimes done to check for a thyroid problem, rheumatoid arthritis, or another medical problem.