The thumb is generally considered to be the most important single digit in the hand. This joint is very near the wrist and under the fleshy part of the thumb. It is subjected to an unusual amount of stress, as the thumb must be strong enough to counteract the force of four fingers put together. The joint is held in position by the contours of its surface and by the ligaments and muscles surrounding the joint.
Arthritis is a common term meaning inflammation of a joint.
Symptoms of arthritis in the base of the thumb are pain and swelling about the thumb and wrist, particularly with grasp and pinch. When the doctor examines the joint, an attempt is made to determine accurately whether the patient's pain symptoms are due to an arthritis in the thumb basal joint. Tests to determine loosening of the joint as well as the smoothness of the cartilage surfaces are performed. X-rays taken of the joint in various positions help the physician determine the severity of the disease. Treatment of the condition depends upon the symptoms and stage of the disease.