Flexor tendons of the fingers or thumb enter a close-fitting tunnel in the palm at the base of the digit, known as the tendon sheath, or pulley mechanism. At this point, swelling of the tendon or tightness of the sheath can prevent free movement of the tendon. Most commonly this results in snapping or locking; the finger may become stuck in flexion and need to be forcibly straightened again, or the tendon become completely stuck either with the finger fully flexed, or unable to flex. Sometimes the condition comes and goes, but more often it persists once it has started to occur. Mild triggering may be alleviated by a steroid injection, but if this fails, or the degree of triggering or locking is more severe, surgical release is indicated and is generally very successful. The operation can be performed under local anaesthetic without admission to hospital, and involves a short scar in a crease in the palm, through which the first part of the pulley mechanism is enlarged by dividing part of it.
Trigger finger may be associated with other medical conditions such as diabetes and rheumatoid arthritis, and the implications of these need to be considered during treatment.
Simple trigger finger release is healed and function should be recovered within about three weeks of the operation.