Developmental dysplasia of the hip

Developmental dysplasia of the hip (DDH) is a spectrum of disorders related to abnormal development of the hip at any time during foetal life, infancy or childhood (Clarke and Dowling 2003). It ranges from mild acetabular abnormality and joint laxity to irreducible dislocation of the femoral head. The cause is thought to be multifactorial including heredity with generalized joint laxity and a positive family history; hormonal with increased maternal hormones prior to delivery leading to joint laxity; intrauterine breech position; oligohydramnios (reduced amniotic fluid) during pregnancy and postnatal positioning – babies who are carried with legs swaddled together are more likely to develop DDH. The condition is more common in firstborn babies and females.

Diagnosis is by postnatal screening which includes Barlow’s test of instability and Ortolani’s sign of reduction. The babies should be examined when warm and comfortable, preferably after a feed. Other signs are extra skin creases, shortening of the limb (Galeazzi’s sign), limitation of abduction or differences between sides and limp or waddling gait in older child.