Thumb splints (orthoses) are the most common first-line treatment for rhizarthrosis. But which type is right for you? This guide covers the evidence on different splint designs, when to wear them, and what to expect.
Types of CMC Splints
Short Opponens Splint (Thumb Spica)
The most commonly prescribed CMC splint. Stabilises the thumb base while allowing finger motion.
- Coverage: Thumb base to just below the MCP joint
- Wrist: Free (not immobilised)
- Evidence: Strong — reduces pain by 30-50% in clinical trials
- Best for: Daytime use during activities
Long Opponens Splint
Extends to immobilise the wrist as well as the thumb CMC joint.
- Coverage: Forearm to thumb tip
- Wrist: Immobilised
- Evidence: Good for acute flares and night use
- Best for: Night splinting, severe flare-ups
Neoprene Thumb Wrap
Soft, flexible support with heat retention. Less rigid than thermoplastic splints.
- Coverage: Thumb base wrap
- Evidence: Moderate — provides proprioceptive feedback and warmth
- Best for: Mild symptoms, sports activities, patient preference for soft splint
Custom vs. Prefabricated
Custom splints are moulded by a hand therapist. Prefabricated are bought off-the-shelf.
- Custom: Better fit, more effective in studies, but requires hand therapy visit
- Prefabricated: Immediately available, lower cost, good for mild cases
- Evidence: Custom splints show 20-30% better outcomes than prefabricated
When to Wear Your Splint
| Activity | Recommendation |
|---|---|
| Opening jars, bottles | Always wear during these activities |
| Writing, typing | If symptomatic — short opponens preferred |
| Cooking, gardening | Recommended — high pinch forces involved |
| Night time | Long opponens splint if night pain present |
| Driving | Thin neoprene wrap if steering wheel grip hurts |
| Exercise/sports | Neoprene wrap for support during activity |
What the Research Shows
- Splinting reduces pain by 30-50% after 3 months of consistent use
- Custom splints outperform prefabricated ones by 20-30% in pain reduction
- Combining splinting with hand therapy exercises gives better results than either alone
- Night splinting is beneficial for patients with morning stiffness
- Minimum recommended wear: 6-8 hours/day for meaningful improvement
- Most patients see improvement within 4-6 weeks of regular use
For more on non-surgical treatments, see our Conservative Treatment Guide.
Medical Disclaimer: Splint type and wearing schedule should be prescribed by your hand therapist or doctor based on your specific condition. This guide is for educational purposes only.