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Congenital Dislocation of the Hip

If congenital dislocation of the hip remains untreated it can cause significant developmental abnormality and dysfunction which may, in some patients, lead to osteoarthritis in early adulthood.
If the pre-discharge examination raises a suspicion of hip dislocation, the newborn should be reviewed again at the age of 2 weeks at a paediatric orthopaedic clinic whose personnel will manage future treatment should it be indicated.
Treatment delay will worsen prognosis.
Clinical examination of the hips must be carried out regularly at the child health clinic. Any instability of the hips and restriction of movement should be recorded on the 6 week and 4 month visits. At walking age, the child should also be observed for a limp.

Hip dislocation is diagnosed in approximately one newborn out of a hundred. In the majority of cases, an unstable hip becomes stable without any intervention during the first two weeks of life.
The risk factors of hip dislocation include female gender, family history of the disorder, breech delivery and developmental abnormalities of the lower extremities.

A gentle examination with warm hands is pain free, and the child will not cry.
Place your thumb and index finger around the child's knee, and your middle finger on the greater trochanter.
With the child lying down flex the knees to 90° and note any length discrepancy of the thighs, test the range of movement (into abduction) and stability of the hips.
Test the stability of each hip separately.
Abduction will reduce a dislocated hip, and the examiner will usually feel a “clunk” as the hip returns to its place (Ortolani +). However, if the acetabulum is abnormally broad, a "clunk" will not necessarily be felt.
An unstable hip in its correct position can be dislocated by applying gentle lateral pressure on the femur with a thumb on the medial aspect (Barlow +). In the absence of other signs, asymmetric inguinal skin folds and clicks during examination have no pathological significance.
Dislocation of the hip will lead within a few months to the shortening of the adductor muscles which will be evident as an abduction deficit. In this case, reduction of the dislocation is not always possible and instability will not be recordable.
When the child reaches walking age, the dislocation will manifest itself as abnormal gait.
A child whose hips show asymmetric or bilateral abduction deficit, and a child with a marked limp, must be referred to a paediatric orthopaedic clinic. The need for imaging investigations is decided by a paediatric orthopaedic surgeon.

Up to the age of 2 weeks, it is possible to reduce and support an unstable hip with the thighs abducted to about 60°-70° abduction and flexed into 90°. The treatment often consists of a von Rosen splint worn for 6-8 weeks.
If the diagnosis is delayed, the time required for immobilisation will be prolonged and closed reduction may no longer be possible.