Pathophysiology
Rheumatoid arthritis is a systemic immune-mediated inflammatory disease. Persistent synovitis damages cartilage, bone, tendons and stabilising ligaments.
Modern disease-modifying treatment has reduced the frequency of severe classical deformity, but established damage still requires surgical management in selected patients.
Rheumatoid synovitis damages:
- joint cartilage
- capsule
- ligaments
- tendon sheaths
- tendons
- bone
Deformity results from both tissue destruction and chronic imbalance of forces.
Modern disease-modifying therapy has altered the frequency and severity of classic hand deformities, but the principles remain important.
Typical problems
- DRUJ and ulnar-sided wrist destruction
- extensor tenosynovitis and tendon rupture
- carpal collapse and ulnar translocation
- MCP ulnar drift and volar subluxation
- swan-neck or boutonnière deformity
- thumb deformity
- flexor tenosynovitis and carpal tunnel syndrome
Assessment
Before surgery determine:
- pain versus functional deficit
- active inflammatory disease
- tendon continuity
- flexible versus fixed deformity
- adjacent-joint disease
- cervical-spine involvement where clinically relevant
- medical treatment and perioperative immunosuppression plan
Surgical principle
Treat the lesion that threatens function first. A classic example is extensor tenosynovitis with impending tendon rupture.
Operations may include:
- tenosynovectomy
- distal-ulnar procedures
- wrist arthrodesis or selected arthroplasty
- MCP arthroplasty with soft-tissue balancing
- tendon transfer for rupture
- PIP/DIP reconstruction or fusion depending on deformity
- thumb reconstruction tailored to the involved joints
Tendon rupture
Vaughan-Jackson pattern describes sequential ulnar-to-radial extensor tendon rupture associated with attrition around the distal ulna.
EPL rupture and flexor tendon rupture can also occur. Reconstruction often uses tendon transfer because direct repair may not be possible in attritional rupture.
Attrition over prominent distal ulna or inflamed tendon sheath can lead to sequential extensor ruptures. Loss of extension may therefore represent tendon rupture rather than nerve palsy.
A painful swollen tendon sheath can be a warning sign before rupture.
Principle
Surgery should be coordinated with rheumatology and hand therapy. Correcting a deformity without controlling active synovitis or considering the whole kinetic chain gives poor results.
Common deformities
Patterns include:
- ulnar drift at MCP joints
- volar MCP subluxation
- swan-neck deformity
- boutonnière deformity
- caput ulnae and DRUJ pathology
- extensor tendon rupture
- thumb deformity
These should be analysed individually because the operative solution depends on flexibility, joint destruction and tendon integrity.
Examination
Assess:
- disease activity
- flexible versus fixed deformity
- tendon continuity
- passive joint correction
- wrist position
- MCP/PIP/DIP joints
- thumb
- sensation
- cervical-spine symptoms before major surgery in severe rheumatoid disease
Treatment strategy
Coordinate with rheumatology and optimise systemic disease.
Surgical priorities often follow:
- pain
- tendon rupture/risk
- unstable or destructive wrist
- functionally disabling finger deformity
Correcting a distal deformity without addressing a major proximal driver can fail.
Procedures
Depending on pathology:
- synovectomy in selected persistent disease
- tendon repair/transfer
- distal ulna procedures
- wrist fusion or arthroplasty
- MCP arthroplasty
- soft-tissue balancing
- PIP fusion/arthroplasty according to digit and function
FRCS synthesis
The rheumatoid hand should be viewed as a linked kinetic chain. Define the painful or unstable level, tendon status and flexibility before selecting surgery.