OA end stage disease and salvage

Question 1

What are the different treatment options for OA in low motion joints?

Answer 1

• No radiographic changes -> intra-articular medication
• Once radiographic changes present, joints will continue to degenerate
  Options:
  1. Pain relief and work horse
  2. Arthrodese joint (chemical or surgical)

Question 2

What are the low motion joints of the horse limb?

Answer 2

Proximal interphalangeal joint, carpometacarpal joint, tarsometatarsal and distal intertarsal joints

Question 3

what is the principle behind arthrodesis of joints?

Answer 3

• Principle is to destroy the cartilage, induce inflammation and arthrodesis
• Must maintain good analgesia throughout

Question 4

What are the 5 methods that will cause arthrodesis of joints?

Answer 4

• Intra-articular steroids (lasts 1-3 months) (and work the horse)
• Systemic NSAIDs (long term use and toxicity) (and work the horse)
• Neurectomy (disease continues, consequences of loss of sensation, nerve often regrows)
• Chemical arthrodesis for tarsal joints
  
  • 60-80% sound long term with MIA or ethanol1,2 (case selection and contrast studies essential)
• Surgical arthrodesis
  
  • Tarsal joints – drill cartilage (60-80% sound long term) Requires up to 12 months
  • Proximal interphalangeal, metacarpophalangeal and carpometaphalanegal joint – fixation with plate and screws

Question 5

which joint is affected here?

Answer 5

chronic pastern joint arthritis - large osteophyte with new bone formation

Question 6

when should euthanasia be considered for OA?

Answer 6

• Arthrodesis of low motion joints can have a good long term prognosis
• Other joints must be healthy
• Opposite limb must be sound or treatable
• Prognosis for hindlimbs better than forelimbs as bear less weight