osteochondrosis Flashcards
what is ocd
a disturbance in the condral ossification
pathophys of ocd
disturbance of cellular differentiation in growing cartilage
vascular supply in canals btw MC3 and P1 can close and lead to demarcation of a piece of cartilage
result of ocd
resorption or incorporation in joint capsule
steps of ocd
loading –> mechanical insult –> fragmentation in week points
causes of ocd
genetic predisposition
nutrition
biomechanical forces
endocrine cactors
genetic predispositon
look for hereditability index, age
if .24-.25 then can get rid of the problem
if >.24 there is selection
growth rate
genetically predisposed
large, heavy foals - more ocd
increased carbohydrates in the diet
hyperinsulinaemia –> removal of t3 and t4 from circulation which are important for chondrocyte differentiation
healing capacity of ocd
once a lesion appears, a repair process starts immediately
high metabolic activity which naturally declines making repair process harder
lesions that arent repaired develop into articular defects
predilection sites
cervical spine
shoulder
fetlock - saggital ridge of MC/MT III
femoropatellar joint - lateral femoral trochlea
hock - distal intermediate ridge of tibia
clinical forms of ocd
flattening of joint surface
cartilage flaps without rad changes
cartilage flaps free in joint
cartilage with subchondral bone changes
ocd fragments free in joint
diagnosis of ocd
juvenile horses - 4months - 2yrs
joint effusion
lameness
normal synovial fluid
its a degenerative joint disease
conservative treatment of ocd
box rest
controlled exercise
not recommended
surgical treatment of ocd
arthroscopy
advantages of arthroscopy
less tissue trauma
shorter recovery time
less complications
better cosmetics
better prognosis
cause of subchonrdal bone cysts
juvenile horses
tear in weight bearing cartilage
where do cysts occur
inside lining of fibrous tissue, fibrocartilage, necrotic bone
cloaca (communication with joint)
sc
diagnosis of cysts
xray
sctingraphy
predilection sites of cysts
medial femoral condyle
distal MC III/MT III
medial prox radius epiphysis
distal phalanx
scapula
clinical signs of cysts
lame after work
6month - 2yrs
intermittent lamenss
joint effusion not always present
treatment of cysts
steroid injection into cyst
extra articular approach and PTH
enucleation of cyst inside lining
position screw through cyst
defect filled out withTGF-1 and Ca activated thrombin and fibrinogen
OCD vs OC
ocd = degenerative process
oc - is equal to inflammation
