Degenerative Joint Disease Flashcards
What is degenerative joint disease?
An end-stage of several different joint diseases
A progressive inflammatory disorder resulting in cartilage degradation.
DJD vs OA?
DJD - Just inflammatory and cartilage changes
OA - Imaging evidence of bone remodelling
What are the types of synoviocytes?
Type A: Modified macrophages
Type B: Metabolically active fibroblasts
What are the characteristics of DJD?
Degeneration of articulate cartilage
Later stages, also bone changes
What common conditions cause DJD?
Trauma Infectious inflammation Non infectious inflammation Developmental disease \+ Dysplasia \+ Angular limb deformity \+ Flexural limb deformity \+ Osteochondrosis
Immune mediated is very rare in the horse
What is the inflammatory pathophysiology of DJD?
Articular cartilage:
Breakdown products and production of matrix metalloproteinases (destructive enzymes) and relase of catabolic cytokines
Synovial membrane:
Prostaglandins, leukotriene and cytokine release
Subchondral bone
Altered load absorption - cartilage damage
Describe the pain perception in cartilage damage…
No pain receptors in cartilage but are present in the joint capsule.
Synovitis and joint distension painful
Exposure of subchondral bone painful
What is the role of soft tissue in cartilage degradation?
Synoviocytes release mediators and enzymes:
MMPs, PG, cytokines
Increased levels of these mediators can be measures in the joint fluid
What may you find on synovial fluid analysis with DJD?
Similar to normal
Only worth check if bacterial involvement
What are the radiographic features of DJD?
New bone deposition
Soft tissues - Effusion, mineralisation
Subchondral bone sclerosis (increased opacity)
What are the treatment goals for DJD?
Pain reduction
Stop inflammation
Chondroprotection
What are the treatment stragegies for DJD?
Weight control Exercise/physio Strategic analgesia Joint supplements Salvage procedures
What are medical treatments for DJD in the large animal?
NSAIDs/ Intra-articular steroids/other analgesia Glycosamineglycans Sodium hyaluronate Supplements: Chondroitin, glucasamine
What are the side effects of intraarticular corticosteroids?
Negative effect on cartilage metabolism and healing:
- Decreased proteoglycan synthesis
Risk of iartogenic joint infection
Laminitis - probably not but people worry
What commona NSAIDs are used in large animal orthopeadics?
Phenylbutazone
Suxibutazone
Meloxicam
Flunixin meglume
