For a 73‑year‑old with activity‑related carpometacarpal joint pain likely due to overuse (e.g., typing), is a thumb‑spica splint beneficial and what duration (hours per day and total weeks) should it be worn?

Thumb Splinting for Overuse-Related Carpometacarpal Pain

Yes, a thumb spica splint is beneficial for this patient's overuse-related thumb carpometacarpal joint pain and should be worn continuously for 3-6 weeks, with consideration for nighttime-only use thereafter if symptoms persist. 1, 2, 3

Evidence for Splint Effectiveness

Splinting provides significant pain relief and functional improvement for thumb base osteoarthritis. The EULAR guidelines specifically recommend splints for thumb base OA, with evidence showing that full splints (covering both thumb base and wrist) provide superior pain relief compared to half splints that only protect the thumb base (effect size 0.64, NNT = 4 for daily activity improvement). 1

Research demonstrates that carpometacarpal splinting:

• Relieves basal thumb pain by approximately 50% 4
• Improves pinch strength and intrinsic muscle activity 4
• Reduces pain, stiffness, and improves hand function scores significantly compared to no splinting 5
• Increases both grip and pinch strength measurements 5

Specific Wearing Schedule

Initial immobilization period: Wear the splint continuously for 3-6 weeks minimum to allow adequate soft tissue healing and reduce inflammation. 2, 6

After initial period:

• If symptoms improve significantly, transition to wearing the splint primarily during aggravating activities (such as typing) and at night 3
• Custom-made thermoplastic or neoprene orthoses used for at least 3 months show beneficial effects on pain and function 3
• Long-term use is advocated for sustained symptom relief 3

Type of Splint

A full thumb spica splint that includes wrist immobilization is superior to thumb-only splints for pain relief and functional improvement. 1, 7 The splint should be custom-made or well-fitted, as poorly fitted orthoses lead to poor compliance and treatment failure. 3

Adjunctive Treatments

Combine splinting with:

• Topical NSAIDs as first-line pharmacological treatment due to favorable safety profile 1, 3
• Hand exercises to improve joint mobility, muscle strength, and thumb base stability after the initial immobilization period 3
• Activity modification to reduce repetitive loading during the healing phase 1
• Local heat application (such as paraffin wax) before exercises may provide additional benefit 1

Expected Outcomes

Early-stage disease responds best to conservative treatment. In one prospective study, patients with Eaton stage 1 disease achieved an average of 23 months of relief with injection and 3 weeks of splinting, while more advanced stages showed variable results. 6 Prefabricated carpometacarpal-metacarpophalangeal immobilization splints demonstrate significant improvements in pain scores, function scores, and strength measurements after 6 weeks of use. 5

Important Caveats

Monitor for potential adverse effects of prolonged immobilization:

• Muscle deconditioning from excessive immobilization 1
• Skin breakdown from poorly fitted splints 1
• Increased compensatory movement patterns 1

Re-evaluate at 6 weeks: If no improvement occurs by 6 weeks, long-term relief is unlikely with splinting alone, and surgical consultation should be considered. 6 However, given this patient's overuse etiology rather than advanced osteoarthritis, conservative management with splinting combined with activity modification should be highly effective.