In an otherwise healthy adult with de Quervain tenosynovitis, how long should a thumb‑spica splint be worn?

Duration of Thumb Spica Splinting for De Quervain's Tenosynovitis

A thumb spica splint should be worn continuously for a minimum of 3 to 6 weeks, with optimal benefit requiring at least 3 months of consistent use during activities of daily living and at night. 1, 2

Initial Immobilization Phase

• Continuous splint wear for 3–6 weeks is necessary to permit soft-tissue healing and reduce inflammation in the first dorsal compartment. 1
• The splint should be a custom-made thermoplastic or neoprene orthosis that covers both the thumb base and wrist (full thumb spica), as this design provides superior pain relief compared to thumb-only splints. 3, 1
• Splinting for less than 3 months shows no significant clinical benefit; shorter durations are ineffective. 2

Transition to Activity-Based Wear

• After the initial 3–6 week continuous immobilization period, the splint can be transitioned to use primarily during aggravating activities (such as repetitive gripping, lifting, or typing) and continued at night if symptoms persist. 1
• Long-term splint use for at least 3 months is advocated to maintain sustained symptom relief in overuse-related cases. 1, 2

Evidence Supporting Extended Duration

• The European League Against Rheumatism found that custom-made orthoses worn for ≥3 months demonstrated beneficial effects on pain and function, with a pooled effect size of 0.64 and a number-needed-to-treat of 4 for improvement in daily activities. 3, 1
• No improvements are evident with splint use shorter than 3 months; this is a critical threshold for clinical benefit. 3, 2

Adjunctive Measures During Splinting

• Topical NSAIDs (such as diclofenac gel) should be applied as first-line pharmacologic treatment during the splinting period due to their favorable safety profile and moderate effect size. 3, 2
• Activity modification to reduce repetitive thumb loading during the healing phase is essential. 1
• After the initial immobilization phase, hand exercises targeting joint mobility, muscle strength, and thumb-base stability should be initiated. 3, 1
• Local heat application (such as paraffin wax) before exercises may provide additional symptomatic benefit. 1, 2

When to Add Corticosteroid Injection

• If symptoms remain severe after 3 months of appropriate conservative management (including proper splinting duration), intra-articular corticosteroid injection should be considered. 3
• A 2023 network meta-analysis found that adding 3–4 weeks of thumb spica immobilization to corticosteroid injection provided statistically significant short- and mid-term functional benefits (mean difference 10.5 points on Q-DASH at short-term, 9.4 points at mid-term). 4

Common Pitfalls to Avoid

• Do not expect benefit from splints worn for less than 3 months—this is the most common error in splinting for de Quervain's tenosynovitis. 3, 2
• Ensure proper splint fitting to prevent skin breakdown and discomfort, which can reduce compliance. 1
• Monitor for muscle deconditioning with prolonged immobilization and initiate strengthening exercises after the initial healing phase. 1
• Do not continue conservative management indefinitely without reassessment; escalate to corticosteroid injection or surgical consultation if symptoms remain severe after 3 months of appropriate splinting. 3