Perthe's disease

Question 1

What is Perthe’s disease?

Answer 1

A degenerative condition which affects the hip joint of children

Question 2

Which ages does Perthe’s disease occur between?

Answer 2

Occurs typically between ages 4 - 8 years

Question 3

What is the pathophysiology of Perthe’s disease?

Answer 3

1. Avascular necrosis of the femoral head specifically the femoral epiphyisis
2. Impaired blood supply to the femoral head causes bone infarction

Question 4

What is the incidence of Perthe’s disease?

Answer 4

1. 5 x more common in boys

2. 10% of cases are bilateral

Question 5

What are the features of Perthe’s disease?

Answer 5

1. Hip pain - develops progressively over a few weeks
2. Limp
3. Stiffness and reduced range of hip movement

Question 6

What does an x ray in Perthe’s disease show?

Answer 6

1. Widening of joint space

2. Decreased femoral head size / flattening

Question 7

How is Perthe’s disease diagnosed?

Answer 7

1. Plain X ray

2. Technetium bone scan / MRI

Question 8

Complications for Perthe’s disease?

Answer 8

1. Osteoarthritis

2. Premature fusion of growth plates

Question 9

What is the staging for Perthe’s disease called?

Answer 9

Catterall staging

Question 10

Stage 1 - Catterall staging

Answer 10

Clinical and histological features only

Question 11

Stage 2 - Catterall staging

Answer 11

1. Sclerosis

2. Preservation of articular surface

Question 12

Stage 3 - Catterall staging

Answer 12

Loss of structural integrity of femoral head

Question 13

Stage 4 - Catterall staging

Answer 13

Loss of acetabular integrity

Question 14

Mx of Perthe’s disease

Answer 14

1. Conservative Mx
   - keep the femoral head within the acetabulum
2. Surgical Mx in severe cases

Early intervention = Better outcomes