Trigger Finger / Thumb

What is Trigger Finger / Thumb?

Stenosing tenosynovitis is the medical name for trigger finger (or thumb). It is a disorder characterized by discomfort or “catching” of a flexor tendon on movement of the finger. Occasionally the digit can present in a locked, flexed position. This is caused by degeneration and tightening of one of the pulleys that guide the flexor tendons resulting poor gliding of the tendon through its tunnel. The tendon usually becomes swollen and forms a nodule and in essence the tendon becomes too tight to pass through the pulley.

What are the causes?

The cause is unknown, but the theories include degeneration of the pulley, causing it to become less yielding and tighter. It is commoner in diabetic patients and patients with rheumatoid arthritis. It tends to occur in patients over the age of 50, however it can present in newborn infants; usually caused by a congenital tightness in the pulley.

What is the Treatment?

If symptoms are mild and the finger is not locked in position, an injection of steroid and local anaesthetic is advised. This acts by dampening down the inflammation and give the tendon more space to move. If the locking is severe, affecting multiple digits, is associated with diabetes or is recurrent, surgery is usually advised. The operation can be performed as a day case under local anaesthetic. It involves a small incision in the palm of the hand, and the tight pulley is divided, allowing the tendon to glide easily.

What are the complications?

The surgery is extremely safe and the success rate is over 95%. The complications are rare (less than 1%) but include stiffness and recurrent triggering, nerve or artery injury and an abnormal pain response.

What is the recovery period?

The operation requires immediate movement to reduce the risk of scarring around the tendon and recurrence. Most patients are back to full activity by 3 weeks.