What is the recommended treatment for an overuse injury involving the thumb and index finger?

Treatment for Overuse Injury of the Thumb and Index Finger

Splinting is the recommended first-line treatment for overuse injuries involving the thumb and index finger, with full splints (covering both thumb base and wrist) providing better pain relief than partial splints. 1

Conservative Management Approach

1. Splinting/Bracing

• Full splints that cover both the thumb base and wrist are more effective than partial splints for pain relief (Effect Size = 0.64) 1
• The Number Needed to Treat (NNT) for improvement in daily activities with full splints is 4 1
• Neutral wrist splints should be worn full-time initially to immobilize the affected area 2
• For thumb-specific overuse injuries, splints should be designed to prevent lateral angulation and flexion deformity 1

2. Pain Management

• Topical treatments are preferred over systemic treatments for mild to moderate pain 1
  • Topical NSAIDs are effective for pain relief (Effect Size = 0.77) and as effective as oral NSAIDs but with fewer gastrointestinal side effects 1
  • Topical capsaicin is effective with an NNT of 3 for clinical improvement within 4 weeks 1
• If needed, oral medications:
  • NSAIDs are recommended as first-line treatment 3
  • Acetaminophen (up to 4g daily) can be used if NSAIDs provide inadequate relief 3

3. Rehabilitation Protocol

• Follow a phased approach to rehabilitation 3:

  Phase	Focus	Duration
  Initial	Pain control and protected range of motion	0-4 weeks
  Intermediate	Progressive strengthening exercises	4-8 weeks
  Advanced	Occupation-specific training	8-12 weeks

• Exercise therapy should include:

  • Quadriceps strengthening exercises 3
  • Hip strengthening exercises (combined approach shows better efficacy) 3
  • Manual therapy of the lower quadrant 3

4. Acute Phase Management

• RICE protocol (Rest, Ice, Compression, Elevation) for initial pain and inflammation management 3
• Immediate functional treatment rather than complete immobilization 3
• Begin with pain-free activities and gradually progress to low-load strengthening exercises 3

When to Consider Surgical Intervention

Surgical consultation should be considered if:

• Pain persists despite 3-6 months of well-managed conservative treatment 3
• Functional limitations significantly impact quality of life 3
• Progressive joint degeneration is evident on follow-up imaging 3

Return to Activity Criteria

Return to full activity is permitted when the patient demonstrates:

• Complete resolution of pain during and after activity 3
• Full range of motion compared to the uninjured side 3
• Strength symmetry >90% compared to the uninjured side 3
• Successful completion of activity-specific functional tests 3

Common Pitfalls and Caveats

• Splint fit is crucial: Close follow-up after bracing or splinting is essential to ensure proper fit and use 2
• Don't underestimate the thumb's importance: The thumb accounts for up to 50% of overall hand use, with special functions including opposition, retroposition, palmar abduction, and radial abduction 4
• Consider ergonomic solutions: Decreasing thumb motions and forceful thumb pressures encountered at work can prevent recurrence 4
• Recognize when conservative management is failing: Most overuse injuries respond to conservative management, but chronic or recurrent cases may require surgical intervention 5
• Monitor for specific conditions: Repetitive and/or forceful thumb movements can cause or aggravate stenosing tenosynovitis ("trigger thumb"), de Quervain's tenosynovitis, and carpometacarpal joint arthritis 4

While there is limited high-quality evidence specifically for thumb and index finger overuse injuries, the available guidelines and research support splinting as the primary intervention, with a comprehensive approach that includes appropriate pain management and rehabilitation protocols.