View source for Physeal Dysplasia with Slipped Capital Femoral Epiphysis

*Slipped capital femoral epiphysis seen in dogs, foals and calves 
*Associated with severe trauma
*Pigs – manifestation of [[Joints Developmental - Pathology#Osteochondrosis|osteochondrosis]] with only minimal trauma required
*Most common type of physeal fracture in small animals and the proximal femur is the most common site
*In horses, physeal dysplasia is synonymus with [[Physitis|physitis]]


'''More about Physeal dysplasia'''


*Also seen in the coypu with minimal trauma
*Femoral head physes contribute 30-40% of longitudinal growth of the femur in small animals
*Slipped epiphysis -> Salter-Harris type I where only the physis is involved 
**Most common type of physeal fracture in small animals and the proximal femur is the most common site
**In traumatic cases, the fracture crosses through mutiple zones of the physis, with chondrocytes maintaining their linear arrangement on both sides of the fracture site for 1-4d following trauma
*Slipped capital femoral epiphysis – seen in humans, mainly adolescent boys, autosominal dominant with variable penetrance


In cats:
*'''[Physeal dysplasia with slipped capital femoral epiphysis in 13 cats. Craig LE. Vet Path (2001) 38 92-7]'''
**Age 12-21months
**90%  males
**Often obese, lots of Siamese cats
**Normal growth plates close at 7-9mths so these physes should have been closed
**Histology – physeal dysplasia with persistence of an open, disorganized growth plate
***Wide physis, necrotic cartilage at the cleavage site
***Irregular clusters of chondrocytes separated by abundant chondroid matrix. Similar lesions in femoral neck.
**No necrosis of the femoral head, although there is usually a small areas of peripheral attachment at the perichondral fibrocartilagenous complex – could provide some vacularization **The ligamentum teres provides no blood supply to the femoral head
**Clusters of chondrocytes present on either side of the cleavage site
**Differs from [[Joints Developmental - Pathology#Osteochondrosis|osteochondrosis]] by:
***More diffuse affecting the whole physis (in OC – focal failure of endochondral ossification)
***Chondrocytes are arranged in disorganized clusters rather than parallel rows 
***The cat breeds have not been selected for rapid growth
**Insulin may have a role to play – most of the cats were obese....Similar deal to horse osteochondrosis



[[Category:Bones - Degenerative Pathology]]