Trigger Finger: Limitations and Treatment Algorithm
Trigger finger causes significant functional limitations including clicking, catching, locking of the affected digit, and loss of motion that impairs hand function and activities of daily living, with treatment success rates varying from 66% with splinting to 84% with corticosteroid injection. 1, 2, 3
Primary Functional Limitations
Hand stiffness and loss of finger motion are the most functionally disabling complications that can develop if trigger finger is not properly managed, requiring aggressive intervention to restore function. 4, 5
- Clicking and catching during finger flexion and extension represent the hallmark mechanical limitation 1, 2
- Complete locking of the digit in flexion or extension occurs in severe cases, preventing normal hand use 2
- Pain at the A1 pulley region limits grip strength and hand function 1, 2
- Loss of active range of motion develops progressively, particularly if symptoms persist beyond 6 months 3
- Impaired activities of daily living including gripping, grasping, and fine motor tasks become increasingly difficult 6
Treatment Algorithm Based on Severity and Duration
First-Line Conservative Management
For symptoms less than 6 months with mild to moderate triggering, begin with splinting of the metacarpophalangeal joint at 10-15 degrees of flexion for 6 weeks, which achieves 66% success rate. 3
- Splinting is most effective for single digit involvement and symptoms of less than 6 months duration 3
- Success drops to 50% for thumbs compared to 70% for fingers 3
- Activity modification should accompany splinting to reduce repetitive flexion stress 1
Second-Line: Corticosteroid Injection
If splinting fails or symptoms are moderate to severe, proceed directly to corticosteroid injection (triamcinolone 40mg in 1mL), which achieves 84% success rate. 3, 7
- Inject corticosteroid alone without local anesthetic to minimize injection pain (VAS 2.0 vs 3.5 with lidocaine) 7
- Injection is more effective than splinting (84% vs 66% success) and should be first-line for marked triggering 3
- Predictors of injection failure include symptoms >6 months duration, marked triggering, and multiple digit involvement 3
Surgical Intervention
Proceed to open A1 pulley release when conservative measures fail, particularly after unsuccessful corticosteroid injection. 1, 3
- All 7 patients who failed injection in one study were cured with surgery 3
- Percutaneous A1 pulley release is an alternative surgical option 1
- Excision of flexor digitorum superficialis slip is reserved for persistent triggering after A1 release or persistent flexion contracture 1
Critical Management Principles
Begin active finger motion exercises immediately for all unaffected joints to prevent the most functionally disabling complication: hand stiffness. 4, 5, 8
- Finger motion does not adversely affect healing and is extremely cost-effective 4, 5
- Delayed motion increases risk of stiffness that requires multiple therapy visits or surgical intervention 4, 5
- Transition to aggressive finger and hand motion exercises when immobilization is discontinued 4
Common Pitfalls
Failure to encourage early finger motion in unaffected digits leads to significant stiffness that is very difficult to treat after healing. 4, 5
- Over-immobilization of the entire hand rather than just the affected digit causes unnecessary complications 4
- Delaying treatment beyond 6 months significantly reduces success rates of conservative management 3
- Using lidocaine with corticosteroid injection increases pain without clinical benefit 7
- Treating multiple involved digits or marked triggering with splinting alone has high failure rates 3