Perthes Disease

Question 1

Define Perthes Disease

Answer 1

Avascular necrosis of femoral epiphysis from an interruption of blood supply (osteochondritis) → revascularisation and re-ossification over 18-36m

Question 2

What is the epidemiology of Perthes disease

Answer 2

mainly boys (5x)
4-8yo

Question 3

What are the risk factors for Perthes disease

Answer 3

Hyperactivity
Short stature

Question 4

What are the signs and symptoms of Perthes disease

Answer 4

Insidious presentation (>4 weeks)
Limp, hip/knee pain → limb shortening
Stiffness and reduced range of movement
Bilateral in 10-20%

Roll test – pt. supine, roll affected hip internally and externally → guarding or spasm (esp. on internal)

Question 5

What investigations should be done for Perthes disease

Answer 5

X-Ray ± MRI (early stages might not show up, so MRI scan may be needed)
- Widening of joint space
- Decreased femoral head size
- “Increased density of femoral head” →
Femoral head collapse/flattening and fragmentation suggestive of osteonecrosis

Question 6

What is the management for Perthes disease

Answer 6

Simple analgesia for pain management
<6 years: observation (mobilisation and monitoring as healing potentials are good at this age)
- Encourage swimming (to keep the hip joint active in the full range of movements), avoid activities that can lead to any heavy impact on the hip joint e.g. trampolines and bouncy castles.
- Non-surgical containment using splints
>6 years: surgery

<50% of the femoral head is involved: conservative e.g. bed rest and traction

> 50% of the femoral head is involved: plaster cast keeping the hip abducted or osteotomy may be required

Question 7

What are the complications of Perthes disease

Answer 7

premature fusion of growth plates ± osteoarthritis