Mid-term results after ultrasound-monitored treatment of developmental dysplasia of the hips: to what extent can a physiological development be expected?

The purpose of this study was to evaluate the radiological outcome after ultrasound-monitored treatment of developmental dysplasia of the hip at the age of 3 years. We retrospectively reviewed the findings of the second radiographic follow-up of 72 consecutive infants (mean age 31.3 months) with residual developmental dysplasia of the hip. Statistical analysis showed significant regression of acetabular index. Nevertheless, nine hips in seven children showed substantial residual dysplasia. Although remodelling of the acetabulum can be expected, there remains a risk of residual dysplasia. For this reason, radiographic follow-up of every once treated hip as well as the initially physiological contralateral hip is necessary.