Also known as stenosing tenosynovitis, trigger thumb is a condition characterized by clicking, catching, or locking as the tip of the thumb moves from a bent position to straight position. The thumb may become locked in a flexed position. Children develop this condition more often than adults and may display symptoms before 12 months of age.
A trigger finger is a condition that involves the tendons in your digits. As your finger bends, the tendon glides through a series of fitted sheathes called pulleys. When the flexor tendon becomes irritated as it moves through a constricting pulley, the tendon and pulley can thicken and form a nodule, making it harder to slide smoothly. The thumb appears bent, and usually the child can release the thumb with effort. Often, a palpable nodule or bump is felt at the base of the thumb in the palm. Trigger thumbs occur sporadically and are not associated with any genetic disorders. In about 30% of patients, the condition develops in both thumbs.
Trigger thumb may resolve spontaneously in a small number of patients. If the thumb remains locked in a flexed position, treatment is recommended. A trigger finger release is a surgical procedure involving a small incision at the base of the thumb. Next, the constricting, fibrous pulley over the flexor tendon is cut. A bandage is applied for 7-10 days after surgery. The risk of trigger thumb recurrence is very small.