OCD Flashcards
What are the two steps to the formation of osteochondrosis?
(Failure of vascular invasion of the cartilage template and then there is not enough blood supply for that cartilage to then ossify into bone so it’s a failure of vascular invasion followed by a failure of ossification)
Horses with OCD are typically slow growing and small/rapidly growing and large (choose).
(Rapidly growing and large)
An excess/deficiency (choose) in energy provided through diet is strongly implicated as a cause of OCD.
(Excess)
An imbalance in what two trace minerals is thought to be a possible cause of OCD?
(Too little copper or too much zinc)
Do subchondral bone cysts occur in areas of gliding or weight bearing?
(Weight bearing, dissecans lesions occur in gliding areas)
What are two reasons you should not use steroids in cases of OCD?
(It can cause ossification of structures that should not be ossified and you don’t want steroids in the joint if you happen to need to go to surgery)
(T/F) A joint with OCD will always have effusion.
(F, most will but some will not especially joints closer to the body)
Flexion/extension (choose) of a joint with OCD will worsen lameness.
(Flexion, due to the effusion usually present and putting further pressure on the joint capsule)
Why may there still be lameness present after blocking a joint with a subchondral bone cyst?
(Because the block can’t block out the bone pain associated with SBCs)
What are two reasons to not immediately jump to surgical correction of OCD/SBC in foals?
(One → they may be able to heal it themselves with time, make sure to monitor/document/radiograph through 18 months of age to ensure proper healing; two → foal bone is much softer than adult bone and that can make discerning the border between normal bone and bone with malacia more difficult)
Debrided OCD beds heal with what type of cartilage?
(Fibrocartilage, not the normal hyaline cartilage found in joints)
What is the minimum amount of time a horse needs to be stall rested post OCD surgery?
(60 days, no turnout, then gradual return to work)
Why is the rehabilitation period longer for subchondral bone cysts corrected by surgery compared to OCD?
(Because SBCs are related to weight bearing surfaces whereas OCD are gliding surfaces)
What main pathology being present along with an OCD lesion or SBC decreases the prognosis?
(Osteoarthritis)
Bilateral OCD lesions occur in about 50% of cases, so you should take radiographs of the contralateral joint. You take a radiograph of a contralateral joint and do not see any changes, can you stop there?
(No, if only the cartilage is sheared off, you will not be able to tell if there is an OCD lesion, further testing (flexion tests, IA blocks, etc.) is warranted especially if lameness noted on contralateral limb)
