Developmental dysplasia of hip

– How to Treat article “ A GP guide to paediatric orthopaedics” Dec 2019, SCHP notes

= spectrum of conditions where the femoral head has abnormal relationship to acetabulum 🡪 unstable hip

• Associated with DS, neuromuscular conditions eg. Spina bifida, CP
• Physiological laxity of hip in newborns usually resolves after several weeks with normal development of acetabulum

Diagnosis

Clinical examination

1. Hip instability demonstrated with Orotlani maneuver or Barlow maneuver
2. Asymmetry of gluteal creases
3. Asymmetry of limb length, particularly if >3/12 age
4. ↓ hip abduction, partic if >3/12 age
5. Positive Trendelenburg pelvic tilt test & lurch (if walking)

Other: Neuro (movement of all limbs, spasticity, ROM, foot abnormality)

• Physical exam (> 3 months to 1 year)
  • limitations in hip abduction
    • most sensitive test once contractures have begun to occur
    • occurs as laxity resolves and stiffness begins to occur
    • decreased symmetrically in bilateral dislocations
  • leg length discrepancy predominates
• Physical exam (> 1 year – walking child)
  • pelvic obliquity
  • lumbar lordosis: in response to hip contractures resulting from bilateral dislocations in a child of walking age
  • Trendelenburg gait
    • results from abductor insufficiency
  • toe-walking
    • attempt to compensate for the relative shortening of the affected side

• Barlows Manoevre
  • try and dislocate the flexed hip with a postero-lateral movement of the proximal femur  = ‘click of exit’
• Ortolani 
  • Then to feel the movement of the reduction of the dislocated hip back into the acetabulum by moving the femoral head anteriorly whilst the hip is abducted =’click of entry’

Risk factors:

1. Female
2. Breech position after K34
3. Very tight swaddling of lower extremity
4. Oligohydramnios
5. intrauterine packaging deformities
   • plagiocephaly
   • foot deformities
   • torticollis
6. family history of DDH

Other: underlying NM dysfunction

Investigations

USS if < 4-6/12 age

•  predominantly cartilaginous nature of the bones make x-rays an unsuitable means of assessing structure
• All babies with any of RFs or with abnormal hip examination should undergo a hip USS and review by paediatrician/ ortho surgeon

XRay if > 6/12 age

Management

• Non-operative
  • abduction splinting/bracing (Pavlik harness)
    •  if < 6 months old and reducible hip. contraindicated in teratologic hip dislocations and patients with spina bifida or spasticity
  • closed reduction and spica casting
    • 6-18 months old and if failure of Pavlik treatment
• Operative
  • open reduction and spica casting  if >18 months old, open reduction and femoral osteotomy

Possible sequelae (if left untreated)

1. Disability
2. Pain
3. OA
4. Disturbed gait
5. Leg length discrepancy
6. Other: Ipsilateral knee problems, scoliosis, back pain

patient info