LA MS 7: LA OCD Flashcards
OCD PP
Failure of endochondral ossification
Vascular Failure
Cartilage gets traumatized while soft so doesn’t turn into bone
Loss of vasculature before have opportunity to turn it into bone
Implicated etiologies for vascular failure
Genetics
Growth rate - linked
Nutrition: low copper, excess zinc or energy
Gender: questionable
Exercise: excess likely involved - more important in propagation than development
All linked together –> genetically predisposed to grow lrg and fast, fed more, large foals have increased trauma to growth cartilage
Exercise and OCD
OCD fragment there - during exercise can wobble –> see CS
Doesn’t mean that exercise caused the OCD!!!
- -didn’t form because started training too young
- -Training led to OCD fragment becoming wobbly and dislodging
CS
Articularepiphseal growth cartilage
Physis
Remodeling, closure of growth plate
Physeal OC
“Physitis, epiphysitis” - growing pains
Most commonly dx’d in distal radius during growth spurt of lrg, fast-growing foals
Uncertain link to OC
Physeal OC CS
Variable Lameness Enlarged physes, tender to palp Look sore Nobly knees Holding the leg up
Physeal OC Dx
Rads - wide, irregular physes, metaphyseal flaring
Physeal OC Tx
NSAIDS, rest - avoid running
None
Self-limiting dz
Good prognosis
Articularepiphseal Complex OC - CS
Synovitis --+/- Lameness --eventually lead to O Lameness --increased after work/flexion Synovitis +/- Lameness typically dramatic w/ free fragments - not necessarily related to prognosis
Synovitis
Tibiotarsal jt effusion “bog spavin”
FP jt effusion “gonitis”
Most Freq OC Lesions - femoropatellar
Lateral trochlear ridge
Patella
Most freq OC locations - hock
Distal intermediate ridge of the tibia
Lat and med trochlear ridges of talus
Medial malleolus
Most freq OCD locations - shoulder
NIGHTMARE
Humerus
Glenoid
Mostly go undx’d until too late because not on people’s lists and shoulder RADS difficult to obtain
–prog terrible if have issues on both sides of the jt
Most freq OC locations - MC/MTphalangeal
Sagittal ridge
Condyles of MCIII and MTIII
Other OCD Locations
Cervical vertebrate - Wobbler’s (OCD in neck facets of C2, C3, and C4)
Tx OC Lesions
Single or multiple fragments
Standard of care: take out fragment, debride bed so that don’t get recurrent jt filling, and fill with graft or MSCs
Lesions that are prob not OC
Medial femoral condyle cysts
Axial palmar/plantar prox phalanx fragments aka PP1
Medial Femoral Condyle Subchondral Bone Cysts
Horses 1-8yrs (DT trauma in younger horses)
QH predisposed - conformational predisposition
Medial Femoral Condyle Subchondral Bone Cysts CS
Effusion
Variable severe lameness - can come and go because has a ball valve. When ball valve closes, synovitis resolves
–pain DT synovitis
Can be pos to flexion tests
PP1 Fragments
Occur at insertion of short distal sesamoidean ligament on P1
–avulsion fracture
–no histologic evidence of retained cartilage
Occurs with greatest freq in STB
Clean articular break (vs OCDs which have a crumbly, brown sugar retention of cartilage)
Tx PP1 Fragments
Fix
Remove
Leave alone
Arthroscopy - frag removal and lesion debridement
PP1 Prognosis
Age of horse
Age of lesions
Extent of lesion
Pretense of OA on RADS or intraop
OCD In cattle
Surgical tx necessary for long term success
Clinicially manifests in 1 jt
Stifle > tarsi > carpi > shoulder > digit
Majority have concurrent OA at time of dx
