• Weekend Wellness: Carpal tunnel affects hands, symptoms differ from arthritis

DEAR MAYO CLINIC: I have a job in which I make repetitive movements with my hand, and have had pain and numbness in my hand for years. I assumed it was due to osteoarthritis, which I was diagnosed with 20 years ago. But my doctor thinks it may be carpal tunnel syndrome. Are the two conditions related? How is carpal tunnel syndrome diagnosed?illustration of hand with carpal tunnel

ANSWER: Although carpal tunnel syndrome and osteoarthritis can happen together, the causes of the two conditions are not related. But if you are diagnosed with osteoarthritis and carpal tunnel syndrome, effective treatments are available for both.

When you have arthritis within your hand, the two most common places to get it are the ends of the finger joints and at the base of the thumb. From your description, it sounds like you may have thumb arthritis. Arthritis happens when the cartilage in your joints wears away. Without cartilage to cushion them, the ends of the bones in the joint rub together. That can lead to a variety of symptoms.

The most common symptom of thumb arthritis is pain at the base of the thumb. Other signs and symptoms may include swelling, stiffness and tenderness at the base of your thumb, a lack of strength when you grasp objects, and a decreased range of thumb motion. A diagnosis of thumb arthritis typically involves a review of symptoms, along with an imaging exam, such as an X-ray, that can show the loss of cartilage.

Carpal tunnel syndrome also affects the hand. Its symptoms, however, differ somewhat from those of arthritis. The most common symptoms of carpal tunnel syndrome are numbness and tingling in your thumb and fingers, except the little finger, which carpal tunnel syndrome does typically not affect. The numbness and tingling may be triggered by activity such as holding a phone or driving. These symptoms also are common at night and frequently wake you from sleep.

In its early stages, people who have carpal tunnel syndrome usually are able to relieve the numbness and tingling by shaking their hands. But as the condition gets worse, the symptoms may no longer respond to this technique. Carpal tunnel syndrome can lead to loss of feeling and weakness in your hand, making it hard to pick up or hold objects.

Carpal tunnel syndrome happens as a result of your median nerve becoming pinched or compressed. That nerve runs from your forearm through a passageway in your wrist, called the carpal tunnel, into your hand. The median nerve controls sensation in the palm side of your thumb and fingers, with the exception of your little finger. It also provides nerve signals that move the muscles around the base of your thumb.

Doctors usually can make a diagnosis of carpal tunnel syndrome by reviewing your symptoms and doing a physical exam. During an exam, putting pressure on the median nerve produces the symptoms of carpal tunnel syndrome in people who have the disorder. An electrodiagnostic test may be performed to determine the presence and severity of the median nerve irritation.

If you are diagnosed with carpal tunnel syndrome and thumb arthritis, the two conditions can be treated at the same time. A splint may be useful for carpal tunnel syndrome, as well as arthritis. In some cases, an injection of a corticosteroid medication can relieve symptoms of both conditions. Pain medications often help relieve the discomfort of arthritis, too.

If symptoms persist, surgery can be an option. For carpal tunnel syndrome, most people get long-term relief with surgery that relieves compression of the median nerve by releasing the ligament that is pressing on the nerve. Although surgery can be helpful for thumb arthritis, too, recovery from that surgery tends to be longer. As a result, doctors tend to rely on nonsurgical treatment first before pursuing surgery for thumb arthritis. Sanjeev Kakar, M.D., Orthopedic Surgery, Mayo Clinic, Rochester, Minn.