What is osteochondrosis?
process of abnormal bone and cartilage formation
What is osteochondritis dissecans?
lesions that penetrate the joint surface, creating inflammation and effusion
What is endochondral ossification?
bone and cartilage formation
Describe the pathophysiology of OCD
- failure of blood vessels to penetrate the calcified cartilage
- occlusion of canals
- epiphyseal necrosis
What are the affects of OCD in young animals?
- thickened cartilage
- cyst-like changes
- degeneration of cartilage
- uncalcified cartilage not vascularized
- cracks in pathological cartilage
What are the affects of OCD in adult animals?
- subchondral fibrosis
- fibrocartilage covers the defect
- sclerosis of subchondral bone
- osteophyte formation
What are the possible etiologies of OCD?
- genetics
- nutrition
- trauma
- combination of multiple factors
What are the nutrition factors that can results in OCD?
- low Ca with high P
- excess zinc
- copper deficiency
- vitamin A and D deficiency
- high protein diet
- high caloric intake
What are the clinical signs associated with OCD?
- synovial effusion (primary sign)
- lameness
- decreased range of motion
- pain on manipulation
- bog spavin for tarsal crural joint
What are the diagnostic procedures for OCD?
- radiology
- scintigraphy
- arthroscopy
- NMR
What are the locations of OCD in order of most frequent to less frequent?
- tibiotarsal joint
- stifle
- fetlock
- cervical vertebrae
- shoulder
Where does OCD occur on the tibiotarsal joint?
- distal intermediate ridge of the tibia
- lateral and medial trochlear ridge
- lateral and medial malleolus
Where does OCD occur on the stifle?
- lateral and medial trochlear ridge
- medial femoral condyle
Where does OCD occur on the fetlock?
- sagittal ridge of MC III
- caudal eminence of P1
- P1 of MC III cyst
Where does OCD occur on the shoulder?
humeral head
What are the treatment options for OCD?
- rest is the best tx
- intra-articular medication
- joint supplements or chondrorpotective agents
- arthrotomy or arthroscopy
Aggrecan provides what?
compressive stiffness to articular cartilage
What forms spongiosa?
osteoblasts using calcified columns
