What are the treatment options for thumb pain that occurs with flexion?

Treatment of Thumb Pain with Flexion

For thumb pain occurring with flexion, begin with a custom-made thumb orthosis worn during activities for at least 3 months, combined with topical NSAIDs as first-line pharmacological treatment, and add hand exercises targeting joint mobility and thumb base stability. 1, 2

Initial Conservative Management

Education and Activity Modification

• Provide education on ergonomic principles, activity pacing, and use of assistive devices to every patient, as this foundational approach improves self-management and has demonstrated efficacy in reducing pain and improving function. 2
• Teach joint protection techniques to avoid adverse mechanical factors that exacerbate symptoms during daily activities. 1

Orthotic Intervention

• Prescribe a custom-made thermoplastic long thumb orthosis to be worn during activities of daily living, as evidence shows beneficial effects on pain when used for at least 3 months. 1, 2
• A full splint covering both thumb base and wrist provides more pain relief than a half splint, with a number needed to treat of 4 for improving daily activities. 2
• Long-term use (minimum 3 months) is essential—no improvements are evident with shorter periods of use. 2

Exercise Therapy

• Prescribe hand exercises aimed at improving joint mobility, muscle strength, and thumb base stability, as multiple trials demonstrate beneficial effects on pain, function, joint stiffness, and grip strength. 1, 2
• Exercise regimens should include both range of motion and strengthening exercises tailored to the specific joint involved. 1
• Important caveat: Benefits are not sustained when patients stop exercising, so emphasize long-term adherence. 2

Adjunctive Physical Modalities

• Consider local application of heat (paraffin wax, hot pack) especially before exercise, as this has shown benefit with a strength of recommendation of 77%. 1

Pharmacological Treatment

First-Line Topical Therapy

• Apply topical NSAIDs (such as diclofenac gel) as first-line pharmacological treatment due to their favorable safety profile, particularly in older patients with comorbidities. 1, 2
• Topical diclofenac shows small improvements in pain and function after 8 weeks compared to placebo, with similar pain relief to oral NSAIDs but significantly fewer gastrointestinal side effects. 2
• Topical treatments are preferred over systemic treatments for mild to moderate pain, especially when only a few joints are affected. 1

Oral Analgesics

• If topical therapy is insufficient, consider oral NSAIDs at the lowest effective dose for the shortest duration necessary. 1
• Do not prescribe oral NSAIDs without assessing cardiovascular, gastrointestinal, and renal risk factors, particularly in elderly patients. 2
• In patients with increased gastrointestinal risk, use non-selective NSAIDs plus a gastroprotective agent, or a selective COX-2 inhibitor. 1
• In patients with increased cardiovascular risk, COX-2 inhibitors are contraindicated and non-selective NSAIDs should be used with caution. 1

Alternative Oral Agents

• Chondroitin sulfate may be used for pain relief and improvement in functioning, though effect sizes are small. 1

Second-Line Interventions

Intra-articular Corticosteroid Injection

• Consider intra-articular corticosteroid injection for painful flares, especially in trapeziometacarpal (thumb base) joint osteoarthritis. 1, 2
• This intervention is particularly useful when conservative measures have provided inadequate relief after an appropriate trial period. 2
• One RCT suggests intra-articular hyaluronic acid may be as effective as corticosteroid for pain relief with potentially more prolonged benefit. 2

Surgical Intervention

Indications for Surgery

• Consider surgery for severe thumb base osteoarthritis with marked pain and/or disability when conservative treatments have failed after at least 3 months of appropriate management. 1, 2
• Numerous studies support surgery as clinically effective for refractory symptoms. 2

Surgical Options

• Simple trapeziectomy alone is as effective as combined procedures but with fewer complications. 2
• Interposition arthroplasty, osteotomy, or arthrodesis are effective treatments depending on the specific joint involved and structural abnormalities present. 1

Critical Diagnostic Considerations

Localization of Pathology

• Determine the exact location of thumb involvement, as treatment differs significantly for interphalangeal joint, metacarpophalangeal joint, or thumb base (carpometacarpal) joint pathology. 2
• The pressure-shear test has 98% overall diagnostic accuracy and 99% sensitivity for carpometacarpal osteoarthritis, superior to the commonly used grind maneuver. 3

Imaging

• Obtain radiographic assessment with at least 2 views if trauma or structural abnormality is suspected to evaluate fracture displacement and articular involvement. 2

Common Pitfalls to Avoid

• Do not expect immediate benefit from orthoses—they must be used for at least 3 months to show effectiveness. 2
• Do not rely on acetaminophen alone for thumb pain, as its efficacy is limited compared to NSAIDs. 2
• Do not continue conservative management indefinitely without reassessment—escalate to injections or surgical consultation if symptoms remain severe after 3 months of appropriate conservative treatment. 2
• Ensure orthoses are well-fitted and custom-made, as poorly fitted devices lead to poor compliance and reduced effectiveness. 4
• Re-evaluate patient requirements and response to treatment periodically, particularly when using oral NSAIDs. 1