Developmental Dysplasia of the Hip

Question 1

What is DDH?

Answer 1

Abnormal development of the hip joint - the femoral head is not stable in the acetabulum. Ligaments may also be lax.

Question 2

What are the RFx for DDH?

Answer 2

5Fs predispose to DDH:

• Female
• First born
• FHx
• Frank Breech birth
• leFt hip

Question 3

Hx features DDH?

Answer 3

• Stiff hip joint
• Different leg lengths
• Child may lean to affected side when standing
• Leg may turn outward on affected side

Question 4

What is the Barlow manoeuvre?

Answer 4

Hip is slid OUT of the acetabulum (passive dislocation).

• Hip and knees flexed at 90 degrees then slightly adducted as thigh pushed posteriorly
• Clunk indicates head of femur moving out of acetabulum

Question 5

What is the Ortolani maneuvre?

Answer 5

• Detects hip sliding back into acetabulum i.e. reduction. Confirms Barlow.
• Legs and knees 90”
• Reduce with abduction of hip and pushing thigh anteriorly
• May have palpable, audible clunk as acetabulum relocates

Question 6

What are the limitations to B and O tests?

Answer 6

• If hip dislocated more than 2 weeks not usually reliable.
• Not +ve after 3 months due to soft tissue contractures.
  Limitation of abduction becomes most consistent finding.

Question 7

Signs of DDH after 12m?

Answer 7

• Assymetry of hip abduction
• Positive Trendelenburg gait
• Positive Galeazzi sign

Question 8

What is the Galeazzi sign?

Answer 8

• Difference in knee height when child is supine with hips flexed, knees bent and feet on examining table. Suggests dysplasia.

Question 9

Ix in ?DDH?

Answer 9

• US less than 6m

- XR more than 6m: ossification of femoral head

Question 10

Mx of DDH?

Answer 10

• 0-6mo: Splints = Pavlik Harness
• 6-18m: Closed reduction procedure, Spica cast x2-3m
• 1.5-5/8y: Open reduction surgery, Osteotomy
• Older: leave dislocated

Question 11

What is the purpose of splinting DDH?

Answer 11

Holds joint in correct position so ligaments tighten. Several months until hip is stable of XR normal.

Question 12

What is the indication and purpose of closed reduction procedure?

Answer 12

If splinting doesn’t work; where hip is enlaced. Hip spica plaster cast worn to keep hip in right position.

Question 13

What is the purpose of open reduction surgery?

Answer 13

• Splint and closed reduction not effective or late diagnosis
• Hip spica after op

Question 14

When is osteotomy indicated?

Answer 14

late diagnosis

Question 15

Pathophysiology DDH?

Answer 15

• Abnormal growth of hip

- Ligamentous laxity (?secondary pregnancy hormones promoting maternal pelvic laxity)

Question 16

PEx features of DDH?

Answer 16

• Limited abduction of flexed hip (below 50-60)
• Affected leg shortening = asymmetry in skin folds and gluteal muscles, wide perineum
• Barlow’s +ve
• Ortolani +ve
• Galeazzi sign

Question 17

What is Galeazzi’s sign?

Answer 17

• Knees at unequal heights when hips and knees flexed

- Dislocated hip (i.e. DDH) on side of lower knee