Trigger Finger (Stenosing Flexor Tenosynovitis)
Stenosing tenosynovitis of the flexor tendon sheath at the <strong>A1 pulley</strong>, causing painful catching or locking of a finger. A common cause of hand pain and disability in adults, peaking in the 5th to 6th decades.
Mechanism and risk
Repetitive gripping causes fibrocartilaginous metaplasia and thickening of the A1 pulley and tendon, so the flexor tendon no longer glides smoothly. Most cases are degenerative or idiopathic.
| Strongly associated | Non-modifiable | Modifiable |
|---|---|---|
| Diabetes (10 to 20% of diabetics, more in insulin-treated), rheumatoid arthritis, gout, hypothyroidism, renal disease | Female sex, age 40 to 60, congenital A1 narrowing | Repetitive gripping (manual trades, racquet sports, musicians), smoking |
Presentation
- Clicking or catching, the hallmark. The finger catches, then snaps through, worst in the morning.
- Locking in flexion, sometimes needing passive extension
- Pain at the A1 pulley (palm, at MCP level)
- Tender palpable nodule (Notta’s node) that moves with the tendon
- Most often the ring finger and thumb, then middle, index, little
| Green grade | Finding |
|---|---|
| I | Pre-triggering, pain only |
| II | Active triggering |
| III | Passive triggering or locking |
| IV | Fixed flexion deformity |
Several digits affected
check for diabetes or inflammatory arthropathy. Secondary trigger finger runs a worse course.
Management
- Activity modification, MCP splint in extension, NSAIDs: mild cases.
- Corticosteroid injection into the tendon sheath: first-line where splinting alone is insufficient. Published series report resolution in about 60 to 90% of cases; a repeat is reasonable after partial response, with lower reported response rates.
- Percutaneous A1 release (needle or ultrasound-guided): minimally invasive option after injection failure.
- Open A1 pulley release: definitive for refractory cases. Performed as a day case under local anaesthesia, with low reported complication rates.
- Treat underlying diabetes. Glycaemic control improves outcomes.
Rule
injection is first-line for most patients, and surgical release is definitive for failures. Diabetic and multi-digit patients respond less reliably, need repeat injections or earlier surgery, and have higher recurrence. Counsel accordingly.
Paediatric note
congenital trigger thumb is a distinct entity, usually presenting in the first year. It often resolves spontaneously. If it persists, surgical release is preferred since injections are less reliable in children.
References
- From diagnosis to rehabilitation of trigger finger, BMC Musculoskelet Disord 2024, doi:10.1186/s12891-024-08192-5
- J Hand Ther 2019, doi:10.1016/j.jht.2017.10.016
- Orthop Clin North Am 2015, doi:10.1016/j.ocl.2015.06.014
Related
Medical disclaimer: this article is general information, not personal medical advice. Always consult a qualified doctor about your own situation.