What is the best type of night splint for thumb and wrist osteoarthritis (OA)?

Best Type of Night Splint for Thumb and Wrist Osteoarthritis

A full splint that covers both the thumb base and wrist is the most effective type of night splint for thumb and wrist osteoarthritis, providing superior pain relief and improved daily function compared to splints that only protect the thumb base. 1

Evidence-Based Recommendations for Splinting

First CMC (Thumb Base) Joint OA

• Strong recommendation: Hand orthoses/splints for first carpometacarpal (CMC) joint OA 1
• Full splints (covering both thumb base and wrist) provide more pain relief than half splints (only protecting thumb base)
  • Effect size = 0.64,95% CI 0.02 to 1.26 1
  • Number needed to treat (NNT) for improvement in daily activities = 4 (95% CI 2 to 13) 1

Other Hand Joints OA

• Conditional recommendation: Hand orthoses for OA in other joints of the hand 1

Splint Design Considerations

Biomechanical Principles

• Optimal thumb CMC splints should:
  1. Prevent motion of the first metacarpal in relation to other metacarpals
  2. Prevent tilting (flexion) of the first metacarpal during pinch
  3. Distribute pressure appropriately 2

Types of Splints Available

• Custom-molded splints: Provide better fit and potentially better outcomes
• Prefabricated splints: More readily available but may not fit as precisely
• Material options:
  • Neoprene: Comfortable, provides warmth and compression
  • Rigid materials: Provide more stability but may be less comfortable

Wearing Schedule

• Night use: Recommended for pain relief and to prevent deformity progression
• Long-term adherence: Critical for effectiveness
  • In one study, 86% of patients wore their splint for more than 5 nights per week at 12 months 3
  • Long-term use (12 months) showed significant improvement in pain and function compared to usual care 3

Clinical Effectiveness

Short-term vs. Long-term Benefits

• Short-term effects (1 month): Limited evidence of immediate pain relief 3
• Long-term effects (12 months): Significant improvements in:
  • Pain reduction (between-group difference: -14.3 [95% CI, -23.4 to -5.2]; P = 0.002)
  • Hand function (between-group difference: -6.3 [95% CI, -10.9 to -1.7]; P = 0.008)
  • Patient-perceived disability (between-group difference: -13.1 [95% CI, -21.8 to -4.4]; P = 0.003) 3

Recent Evidence

• A 2020 study showed that prefabricated CMC-MCP immobilization splints significantly improved:
  • Pain
  • Hand function
  • Grip and pinch strength 4

Potential Pitfalls and Considerations

Common Issues to Avoid

1. Improper fit: Ensure the splint properly stabilizes the CMC joint while allowing MCP and wrist motion as appropriate
2. Inadequate wearing time: Encourage consistent nightly use for optimal results
3. Neglecting wrist component: Evidence suggests full splints (including wrist) are more effective than thumb-only splints 1

Patient Evaluation

• Patients may benefit from evaluation by an occupational therapist for proper fitting and instruction 1
• Custom-made orthoses may improve compliance and long-term use compared to prefabricated ones 5

Algorithm for Splint Selection

1. First-line: Full splint covering both thumb base and wrist for first CMC joint OA
2. Alternative: Custom-molded thumb CMC immobilization splint that excludes the thumb MCP and wrist joints if patient cannot tolerate full splint
3. For other hand joints: Consider specific orthoses designed for the affected joint(s)
4. Material selection:
   • Neoprene for comfort and compliance
   • Rigid materials when maximum stability is required

In conclusion, while there are various splint designs available, the evidence most strongly supports the use of a full splint that covers both the thumb base and wrist for patients with thumb and wrist OA, particularly for nighttime use. This approach provides superior pain relief and functional improvement compared to splints that only protect the thumb base.