Flashcards in Diagnostics Equine Musculoskeletal (Renate) Deck (23):
Waht are the big 7 in orthopaedic disease complexes in horses?
3. Fx (fatigue or impact)
5. Navicular dz
Why are some iaging modalitis chosen over others in horse?
Need for GA - 1% death risk for hroses is a big deal!
What type of image do radiographs produce?
Other names for OA
- arthrosis, DJD
What are osteophytes? What similar structures are seen elsewhere?
> New bone fomation along the 'lip' edges of articular surface (trying to stabilise the joint)
> Inthesiophytes = new bone formation at attachement of a soft tissue structure
Can cartilage be seen on rads?
NO - just see narrowed/widened join space
What is high ringbone?
OA of the pastern joint -> MINIMAL synovial response, straight to swelling d/t palpable bony changes above the coronary band
Outline the stages of pathogeneis assocaited with OA
1. joint effusion (bog spavin in the hock)
- excessive synovial fluid d/t irritation and inflammatio nof the synovial membrane
2. cartilage damage
3. boney damage
How do horses IVDs differ to smallies?
No nucleus pulposus (only fibrous tissue) so dont get disk problems
How are the 3 main stages of damage associated with OA visable on rads?
1. joint effusion and osteophytes
2. articular artilage: narrowed joint space
3. subchondral bone: sclerosis/lucency (lucency worse prognostically as body given up -> lysis)
Wht may narrowing of the joint eventually lead to?
What is surgical ankylosis termed? How is this performed?
- chemical/physical destruction of cartilage
- only possible in low motion joints eg. DIT and IT joints mainly for shock absorption not movement
What is bone spavin?
OA of the DIT and IT joints -> ankylosis
Gol standard diagnostic method for OA?
What is prognosis and tx after dx based on?
> structures affected (high v low motion joints)
> type of disease (1*/2*, traumatic, devlopmental)
> advanced disease? (early v late stage)
How does inflamed synovial fluid appear cf. healthy?
decreased viscosity (MORE watery!!!)
What are corns?
Inflammation of a specific area of hoof wall (dx with hoof testers and hoof knife, easy - shouldnt get to referral stage to be dx wih corns!)
Tx stategies for OA?
- strategic analgesia
- joint supplements
- novel tx concepts
- salvage procedures
- excercise modification/physio
What cause the changes in synovial fluid composition when inflamed?
- PGE2 and MMPs: V proteoglycans, ^ water and ^ collagen breakdown
- IL1 and TNFa
- PG, LT, free radicals and neuropeptides
Where do steroids and NSAIDs act?
> steroids PLA2
- cell membrane phospholipid -> arachadonic acid stage
> NSAIDs COX
- arachadonic acid -> PGs and Thromboxanes
- 5-lipoxygenase pathway -> leukotrienes
pain,swelling and cartilage degradation, heat (inflammation)
Prevention of OA?
- v BCS
- shoeing and correct foot shape
- other things...
Look up aetiology/pathogenesis, clinical signs, imaging signs, Dxx, Dx, Prog and Tx of all the big 7