Upper limb: OA

Question 1

What are the general management options in OA hand?

Answer 1

1. Conservative:
   - activity modification
   - splintage/HT
2. Medical
   - NSAIDS topical and systemic
   - steroid injection
   - ? Hylauronic acid injection
   - ? platelet rich plasma (PRP) injection
3. Surgical
   - debridement +/- autologous fat transfer (German experience - not sure how often done in UK)
   - denervation procedures
   - corrective osteotomy
   - fusion
   -arthroplasty

Question 2

Describe the epidemiology, and differential diagnosis for thumb CMCJ OA

Answer 2

• Commonest joint in hand requiring elective surgery for OA
• F>M
• Usually trapeziometacarpal joint but may be pan-trapezial
• Differential: STT joint OA, De Quervains, Radio-carpal OA

Question 3

Do you know any radiological grading system for OA thumb?

Answer 3

Eaton and Littler (I-IV)

I: subtle CMCJ space widening (due to laxity of joint ligaments)
II: slight CMCJ narrowing, sclerosis and cystic changes with osteophytes or loose bodies <2mm
III: advanced CMCJ narrowing, sclerosis and cystic changes with osteophytes or loose bodies >2mm
IV: Arthritic changes in CMCJ as in III but with scaphotrapezial arthritis

Question 4

Describe the pathogenesis of OA

Answer 4

-destruction of articular hyaline cartilage
- adjacent bone is remodelled with osteophyte formation at joint margins
-Sclerosis of periarticular bone is common
-mild synovitis and inflammatory joint effusions are often present
- most OA is idiopathic (primary); secondary OA is predisposed by:
a. joint injury
b. joint instability
c. joint surgery
d. inflammatory arthropathy (ie RA)
e. neuropathic arthropathy (ie Charcot)

Question 5

What are the typical radiological features of OA

Answer 5

• joint space narrowing
• osteophyte formation
• subchondral sclerosis and cyst formation
• deformity

Question 6

Describe the operative management of DIPJ OA

Answer 6

A: Arthodesis
- often arthrodesis through dorsal approach
- bone surfaces prepared by cup and cone of flat-angled resection technique
-options for fixationL
a. k wires
b. Interossesous wires including Tension band wiring
c. lag screws including a Herbet-type screw
d. plates, including bioabsorbable implants
e. Ex fix
-DIPJ fused in 0-20 degrees of flexion based on patient’s needs

B: Debride DIPJ _/- excision of mucous cyst and osteophyte

C: DIPJ joint replacement (silicone)

Question 7

Describe the operative management of PIPJ OA

Answer 7

1. denervation - good for the younger patient
2. Arthrodesis:
   - fusion angle increase from 40 deg in index to 55 deg in little unless specific occupational or recreational requirements
3. Arthroplasty:
   - silicone vs pyrocarbon vs metal
   - complication upto 20%
   - need motivated and compliant patient (patient selection is key)
   - technically demanding procedures

Question 8

Describe the surgical management options for managing thumb CMCJ OA

Answer 8

1. Osteotomy: abduction-extension osteotomy of the 1st MC base aims to offload the palmar surface of the CMCJ (maybe useful for high demand young adults with early disease)
2. Arthrodesis: useful for post-traumatic OA, fixes thumb out of plane of hand. pts should be warned cant do press ups etc.
3. Arthroplasty:
   a. excision arthroplasty - trapeziectomy +/- K wire
   - volar beak ligament reconstruction and tendon interposition (LRTI) using APL, PL or FCR. Various techniques eg. weaving half of FCR around APL and suturing APL over the imbrications
   b. pyrocarbon hemiarthroplasty?

Question 9

What are some of the reasons why trapeziectomy may fail?

Answer 9

1. incomplete removal of the trapezium
2. neuroma of SBRN
3. Collapsing pinch due to MCPJ hyperextension
   - corrected by capsulodesis, sesamoid tenodesis or MCPJ arthodesis
4. missed pan-trapezial OA
   - gives pain on movement of both thumb and wrist
   - pure STT OA gives pain on wrist movement only (treated by excision of distal pole of scaphoid)