Spectrum
DDH includes:
- acetabular dysplasia with a located hip
- instability/subluxation
- reducible dislocation
- fixed dislocation
It is a developmental spectrum, not simply a congenital dislocation.
Developmental dysplasia of the hip ranges from mild acetabular dysplasia to subluxation and complete dislocation. The hip can change during growth, which is why surveillance and age-specific treatment matter.
Risk factors
- breech presentation
- family history
- female sex
- first-born status
- associated packaging disorders such as torticollis or foot deformity
Risk factors increase suspicion but many affected children have none.
Important associations include:
- breech presentation
- female sex
- family history
- first-born status
- oligohydramnios
- packaging disorders
Risk factors support screening but do not replace examination.
Examination
Infant
- Barlow manoeuvre: tests whether a located hip can be provoked out
- Ortolani manoeuvre: reduces a dislocated but reducible hip
- limited abduction becomes more useful as the child grows
- Galeazzi asymmetry may be present in unilateral disease
Walking child
- limp or Trendelenburg gait
- apparent shortening
- limited abduction
- hyperlordosis/waddling in bilateral dislocation
Imaging
Ultrasound is preferred in early infancy because much of the femoral head is cartilaginous. Radiographs become more useful as ossification progresses.
On radiographs assess:
- Hilgenreiner line
- Perkin line
- Shenton line
- acetabular index
- later, centre-edge relationships where age appropriate
Treatment principles
Goals:
- obtain a concentric reduction
- maintain reduction
- minimise avascular necrosis
- allow acetabular development
Early infancy
A dynamic flexion-abduction harness is first-line for many reducible hips. Failure to achieve and maintain reduction requires prompt change in strategy rather than prolonged ineffective harness treatment.
Older infant
Closed reduction under anaesthesia with arthrography and spica immobilisation may be required.
Open reduction
Indications include irreducibility or inability to maintain a safe concentric closed reduction.
Obstacles can include:
- contracted iliopsoas/adductors
- inverted labrum
- pulvinar tissue
- hypertrophied ligamentum teres
- constricted capsule/transverse acetabular ligament
Femoral shortening/derotation and pelvic osteotomy are added according to age, tension, residual dysplasia and stability.
Complications
- avascular necrosis
- redislocation
- residual acetabular dysplasia
- stiffness
- leg-length inequality
Neonatal examination
The Ortolani manoeuvre attempts to reduce a dislocated but reducible hip. The Barlow manoeuvre assesses whether a located hip can be provoked out of the socket.
With increasing age, these manoeuvres become less useful as soft tissues tighten. Later signs include:
- limited abduction
- leg-length asymmetry
- Galeazzi sign
- asymmetric gait
- increased lumbar lordosis in bilateral disease
Imaging by age
Ultrasound is useful in young infants before the femoral head ossifies sufficiently for radiographs.
Radiographs become more useful later. Important concepts include:
- acetabular index
- Hilgenreiner and Perkin lines
- Shenton line
- femoral-head position and acetabular development
Harness treatment
A flexion-abduction harness can maintain a reducible hip in a position that promotes stable development in selected infants.
It should not be used to force a fixed hip into position. Excessive abduction can endanger the femoral head blood supply.
Failure requires timely reassessment rather than indefinite continuation.
Closed reduction and spica
If harness treatment fails or the child presents later, closed reduction under anaesthesia may be attempted when appropriate. Reduction should be stable and concentric, with careful assessment and spica immobilisation.
Open reduction and osteotomy
Older children or irreducible hips may require:
- open reduction
- femoral shortening/derotation
- pelvic osteotomy
The required procedure depends on age, soft-tissue tightness, femoral version and acetabular deficiency.
Residual dysplasia
A hip can be reduced yet retain acetabular dysplasia. Follow-up through growth is therefore important.
AVN
Avascular necrosis is a major complication of treatment and can result from excessive pressure on the femoral head, forceful reduction or extreme positioning.
FRCS synthesis
Present DDH management by age and reducibility: detect early → obtain a stable concentric reduction → protect blood supply → monitor acetabular development through growth.