Thumb Carpometacarpal Arthroplasty for Advanced Osteoarthritis
Surgery, including interposition arthroplasty, osteotomy, or arthrodesis, is an effective treatment for severe thumb base osteoarthritis and should be considered in patients with marked pain and/or disability when conservative treatments have failed. 1
Evidence Quality and Strength
The EULAR guidelines provide Level III evidence with a strength of recommendation of 68 (95% CI: 56-79), indicating moderate support for surgical intervention. 1 While placebo-controlled RCTs have not been conducted due to methodological and ethical constraints, numerous observational studies support surgery as clinically effective for severe thumb base OA refractory to conventional treatments. 1
A critical caveat: The optimal surgical procedure for thumb base OA remains undetermined, as acknowledged in the EULAR research agenda. 1, 2
Surgical Timing Algorithm
When to Operate:
- Failure of conservative management including activity modification, splinting, topical NSAIDs, oral analgesics (paracetamol up to 4g/day), and exercise regimens 1, 2
- Failure of intra-articular corticosteroid injections for painful flares 1, 2
- Marked pain and/or disability that limits activities of daily living 1, 3
- Advanced radiographic disease (Eaton stages III and IV) 3
Surgical Options and Outcomes
Total Joint Arthroplasty:
- Provides excellent pain relief, improved motion, and strength recovery in advanced disease (Eaton stages III and IV) 3
- At 59-month average follow-up, patients achieved 60° thumb abduction, opposition to small finger base, and 85% pinch strength compared to contralateral side 3
- Best suited for older patients with low activity demands 3
- Complications include implant loosening (rare in one series with only 1/26 cases) 3
Interposition Arthroplasty:
- Burton-Pellegrini procedure (using FCR tendon) provides the best results and fastest recovery (3-6 months stabilization) among soft-tissue techniques 4
- Total trapezium resection superior to partial resection, contributing to better surgical orientation and outcomes 4
- Arthroscopic hemitrapeziectomy with spacer interposition shows excellent short-term results for moderate disease (Eaton stages 2-3), with mean pinch strength returning to 59% of contralateral limb at 1 year 5
ARPE Total Joint Replacement:
- Demonstrates excellent functional results for pain, mobility, and strength with fast recovery (rehabilitation unnecessary) 6
- Most common complications: implant luxation (6/63 cases) and loosening (3/63 cases), both with relatively simple surgical solutions 6
- Preserves option for future trapeziectomy due to minimal metacarpal shortening 6
Common Pitfalls to Avoid
- Do not operate without exhausting conservative measures first, as the treatment algorithm requires stepwise progression through non-pharmacological, pharmacological, and invasive non-surgical options 1, 2
- Avoid total joint arthroplasty in young, high-demand patients where implant longevity is uncertain 3
- Do not perform partial trapezium resection when doing interposition arthroplasty, as total resection yields superior results 4
Evidence Gaps
The EULAR guidelines explicitly identify that the potential benefits of surgery compared with conservative management, and the most appropriate surgical procedure for thumb base OA, remain to be determined. 1, 2 This underscores the need for high-quality comparative effectiveness research, though the existing observational evidence consistently demonstrates clinical benefit across multiple surgical techniques. 1, 7