The joint at the base of the thumb (carpometacarpal joint) is like a saddle, and allows a lot of motion of the thumb at that joint. If the cartilage coating the ends of the bones wears out, bone starts to rub against bone, and arthritis results.
Generally a ‘wear and tear’ phenomenon, with a genetic or family predisposition. More common in women. May be a late result of earlier trauma.
Pain deep in the base of the thumb, relieved with rest, and worsened with pinching, squeezing, and gripping activities. Opening jars, door handles, and turning keys are problematic.
Tenderness at the carpometacarpal joint of the thumb. There may be deformity present, and loss of motion.
History, physical examination, and x-rays are usually diagnostic.
Splinting, anti-inflammatory medication, and rest may reduce symptoms. A corticosteroid injection can provide relief for a while, but will not repair the joint. Thumb splints are effective, but poorly tolerated due to restriction of thumb motion. Physical therapy is contraindicated, as it tends to irritate things.
A joint replacement, or thumb basal joint arthroplasty.
Most patients can be managed non-operatively, but surgical reconstruction is very effective for pain relief, strength, and motion. About four weeks of casting are required after surgery, and up to several months of hand therapy.