RA- MCP JOINT

Question 1

4 main MCPJ deformities in RA

Answer 1

1. Volar subluxation of extensor tendons = caused by attenuation of radial sagittal bands
2. Ulnar drift
3. Volar subluxation
   - caused by volar-ulnar subluxation of extensor tendons
4. Pronation

Question 2

3 main factors to consider in management of MPJ deformity in RA

Answer 2

1. Acuity
2. Correctability
3. Arthritis

Question 3

Surgical options for MPJ deformity in RA

Answer 3

Joint preserving vs. sacrificing or soft-tissue vs. bony

1. MPJ synovectomy + release of ulnar intrinsics + extensor tendon centralisation
2. Arthroplasty = Swanson silicone arthroplasty
3. Arthrodesis

Question 4

Arthroplasty for MPJ pathology in RA:
Advantages
Disadvantages
Indications
Contraindications
Technique

Answer 4

1. Advantages
   - good pain relief (80-90%)
   - preservation of motion = 40deg
2. Disadvantages
   - technically challenging
   - complications = approach (wound, infection), arthroplasty (fracture, loosening, subsidence, silicone synovitis), other (recurrence of deformity)
3. Indications
   - active high-demand patients
   - end-stage arthritis
4. Contraindications
   - active infection
   - poor soft-tissues
   - fixed deformity/ instability/ poor bone stock
5. Technique
   - 10-year survival = 80-90%
   - silicone synovitis not an issue at MPJ

Question 5

Arthrodesis for MPJ pathology in RA:
Advantages
Disadvantages
Indications
Contraindications
Technique

Answer 5

1. Advantages
   - technically easier than arthroplasty
   - good pain relief
2. Disadvantages
   - slower recovery = immobilisation
   - complications = approach (wound, infection), arthrodesis (incorrect position, nonunion)
3. Indications
   - elderly low-demand patients
   - end-stage arthritis
   - deformity/ instability/ poor bone or soft-tissues
4. Contraindications
   - active infection
5. Technique
   - Position of arthrodesis varies by digit
   - 40 to 25deg from LF to IF
   - Fixation with headless compression screw/ plate/ TBW