Trigger finger is a condition causing pain and difficulty moving a finger. It is also known as stenosing tenosynovitis.
Pathophysiology
The flexor tendons of the fingers pass through several tunnels (sheaths) along the length of the fingers. In trigger finger, there is thickening of the tendon or tightening of the sheath. This prevents the tendon from smoothly moving through the sheath when the finger is flexed and extended, causing pain, stiffness, or catching symptoms.
The most commonly affected part of the sheath is the first annular pulley (A1) at the metacarpophalangeal (MCP) joint.
There may be a nodule on the tendon. When the finger is flexed, the nodule is outside the A1 pulley. As the finger is extended from a flexed position, the tendon nodule can get stuck at the entrance to the A1 pulley. This causes the finger to lock or get stuck in the bent position. It may release suddenly with a painful pop or click.
Risk Factors
Patients more likely to be affected by trigger finger are:
- In their 40s or 50s
- Women (more often than men)
- People with diabetes (more with type 1, but also type 2)
Presentation
The typical presentation is with a troublesome finger, that:
- Is painful and tender (usually around the MCP joint on the palm-side of the hand)
- Does not move smoothly
- Makes a popping or clicking sound
- Gets stuck in a flexed position
Symptoms are typically worse in the morning and improve during the day.
Diagnosis
Trigger finger is a clinical diagnosis based on the history and examination findings.
Management
Management options include:
- Rest and analgesia (a small number resolve spontaneously)
- Splinting
- Steroid injections
- Surgery to release the A1 pulley
Last updated August 2021