Rheumatoid Foot

• 17% of RA pts have symptoms in feet first.  Eventually 85% woth l,ong-standing RA have at least minor forefoot involvement
• synovitis

RA Anatomy

• forefoot involvement (most common) leads to claw toe deformities with hallux valgus
• midfoot less involved
• hindfoot usually valgus due to disruption of the talocalcaneal interosseous ligament(has a synovial covering)
• typical deformity= hindfoot valgus, midfoo-forefoot abduction and collapse of medial longitudinal arch. 

RA Treatment

• hip/knee deformities should be treated first
• Non-op=extra-depth shoes with deep toe box and padded heal counters.  Marked hindfoot valgus may require locked or limited motion AFO with a valgus correction T-strap
• End-stage rheumatoid forefoot deformities are best treated with a hallux metatarsophalangeal fusion and lesser metatarsal head resection.  This provides a stable medial column, decompression of the forefoot, and acceptable and predictable long-term results.  Forefoot amputation provides similar success, but is not generally accepted socially. (Hamalainen M, Raunio P: Long-term follow-up of rheumatoid forefoot surgery.  Clin Orthop 1997;340:34-38)
• Steroid injection is appropriate for metatarsophalangeal synovitis. 
• Shortening metatarsal osteotomies may be an option if the metatarsophalangeal joints are salvageable and not eroded.
• Hindfoot deformity=triple arthrodesis c TAL or TAA

RA References

• Clayton ML, Leidholt JD: Clark W: Arthroplasty of rheumatoid metatarsophalangeal joints: An outcome study.  Clin Orthop 1997;340:48-57.