Week 3 - Perthes Disease

Question 1

what is perthes disease also known as?

Answer 1

legg calve perthes disease

Question 2

what is perthes disease?

Answer 2

idiopathic osteochondritis of the femoral head

Question 3

who does perthes disease most commonly present in?

Answer 3

boys age 4-9

- particularly very active boys of short stature

Question 4

what happens in perthes disease?

Answer 4

femoral head transiently looses blood supply resulting in necrosis with subsequent abnormal growth

Question 5

what can perthes disease progress to?

Answer 5

femoral head may collapse of fracture
subsequent remodelling will occur which can change the shape of the femoral head and the congruence of the joint
- incongruent joint can lead to early arthritis and possible hip replacement

Question 6

what determines the shape of the femoral head and the congruence of the joint?

Answer 6

age of onset (older = worse prognosis)

amount of collapse

Question 7

how does perthes disease present?

Answer 7

pain
limp
loss of internal rotation
loss of abduction
positive trendellenburg gait
most are unilateral but can be bilateral

Question 8

what can a bilateral perthes disease presentation represent?

Answer 8

underlying skeletal dysplasia

thrombophilia

Question 9

how is perthes disease treated?

Answer 9

no real treatment
regular X rays
avoidance of physical activity

Question 10

what changes can sometimes occur in the femoral head?

Answer 10

can become aspherical, flattened and widened
can sublux (dislocate) requiring osteotomy of the femur or acetabulum

Question 11

what changes can occur in muscles?

Answer 11

lever arm of the abductor muscles is altered resulting in weakness (trendellenburg gait)