Legg Calve Perthes

Question 1

What is another name to Legg Calve Perthes?

Answer 1

Avascular necrosis femoral head

Question 2

What is the mechanism behind Legg Calve Perthes?

Answer 2

Hypothosis: Temporary vascular compromise -> necrotic phase -> reparative phase, new bone formation (creeping substition)
Excessive resorption -> loss of subchondral bone, collapse of articular cartilage, OA.
Epiphysis vascularied by circumferential vessels.

Question 3

Cause of Legg Calve Perthes?

Answer 3

Autosomal recessive inherence

Question 4

Breed predisposed to Legg Calve Perthes?

Answer 4

Manchester Terriers
West Highland White Terriers

Question 5

Age presentation?

Answer 5

4-11months

Question 6

Clinical presentation?

Answer 6

Progressive onset
Can be acute

Often severily lame, marked mm atrophy, discomfort on manipulation, crepitus

Question 7

Imaging?

Answer 7

XR - frogled and extended

Lucencies -> femodelling, flattened femoral head. sclerosis, OA

Question 8

Treatment?

Answer 8

Salvage surgery (as conservative treatment will lead to significant OA)