Analysis of Ultrasound Scan Findings in Neonates with Increased Risk Factors for Developmental Dysplasia of the Hip

Abstract

BACKGROUND Developmental dysplasia of the hip (DDH) refers to an abnormal ratio between femoral head and acetabulum in neonates. There are well known risk factors for DDH like breech presentation, oligohydramnios, and female gender. In addition, clinical detection of a "click" during neonatal hip examination is taken as an indicator of DDH. Ultrasound (US) scan is the best current screening tool to detect DDH. Universally neonatal hips get screened by clinical examination or US scan or both depending on the guidelines practised according to the institution. In Sri Lanka, all neonates get their hips screened by clinical examination and US scan is offered only to the neonates with additional risk factors. OBJECTIVE To analyse US scan abnormalities detected in neonates with increased risk factors for DDH. METHOD Descriptive analysis of the US scan reports and Bed Head Tickets were done using a Performa in 100 neonates detected to have increased risk factors for DDH. RESULTS There were 52 female babies in our study and all were born at term. The indications for hip US scans were breech presentation in 56% and detection of a unilateral 'hip click' in 42%. Out of all requested, only 96 attended for US scan assessment. Thirty one babies were detected to have shallow acetabula during the initial assessment while repeat scan done after 6 weeks showed that only 4 babies needed an orthopaedic referral. Twenty four babies were found to have shallow acetabula and all babies who needed orthopaedic referral were screened ultrasonically due to a Hip 'Click' detected during neonatal check. CONCLUSION In this study, 24 babies were found to have shallow acetabula on US scan of the hips.