The tendons that bend or flex the fingers pass from the forearm into the palm, and out to the fingers. These tendons pass through a series of tunnels, or pulleys, that hold the tendon down along the bones. This prevents ‘bowstringing’, of the tendon, much like the metal eyelets on a fishing rod prevent bowstringing of the fishing line. If the tendon becomes swollen, it can catch, or get stuck as it tries to pass through a pulley (like a knot in the fishing line).
This is typically an ‘overuse’ injury, due to repetitive or frequent squeezing, gripping, or similar activities. Frequently seen Monday morning after a weekend of heavy pruning and gardening.
Pain in the fingers. There is often a sensation of catching, or ‘triggering’ of the involved digit. The finger may actually lock down into the palm, or lock out straight. Symptoms are usually worse in the morning, and improve during the day.
Tenderness along the flexor tendon sheath, especially at the A1 pulley in the palm. A nodule may be felt moving under the pulley, with finger motion. Locking or catching is classic.
Most cases are straightforward. X-rays may be useful to rule out other injuries or disease, such as arthritis.
A trial of a corticosteroid injection into the flexor tendon sheath, and anti-inflammatory medication is often very effective.
A tendon sheath incision, or release of the involved pulley is curative.
At least half of the cases can be cured non-operatively. A tendon sheath incision is performed under local anesthesia, often in an office setting, with a tiny incision.