Avascular- Perthe's

Question 1

Def.

Answer 1

• Avascular necrosis of femoral capital epiphysis before growth plate closure.
• Usually self-limiting & resolving ~ 2-8 years.

Question 2

Age & View

Answer 2

• Ages 3-12yo -> peak between 5-7

* Importance of frog-leg view to assess alignment of femoral head against neck -> should be symmetrical and complete

Question 3

Radiol Fx.

Answer 3

• Hot bone scan.
• Soft tissue swelling
• increased medial joint cavity width
• smaller obturator foramen
• reduced femoral head size
• lucent clefts across epiphysis
• Metaphysis widened and shorted
• cysts with uncalcified growth plate,
• widened lucent physis.

N.B.

• Positive Klein’s Line!!
• Crescent Fracture Sign

Question 4

4 Stages

Answer 4

1. Asymmetrical
2. Fragmentation (d/t resorption rather than outright destruction)
3. Reparative
4. Healed (+- Deformity)

Question 5

Deformities

Answer 5

1. mushroom cap deformity of femoral epiphysis
   
   2. Coxa magna (large hip)
   3. Coxa varus
   4. Sagging rope sign (of femoral intertrochanteric line)