A normal screening ultrasound does not provide complete reassurance in infants at risk of hip dysplasia; further follow-up is required

Screening of Developmental Dysplasia of the Hip in Europe: A Systematic Review

BACKGROUND

Developmental dysplasia of the hip (DDH) is a prevalent orthopaedic disorder in children, and screening methods vary across regions due to local health policies. The purpose of this review is to systematise the different ultrasound screening strategies for detecting DDH in newborns in Europe.

METHODS

Eligible studies from the PubMed, Embase, and Scopus databases, published between 1 January 2018 and 18 March 2023, were included. The inclusion criteria specified a European origin, a focus on newborn human patients, and information on ultrasound for DDH detection.

RESULTS

In total, 45 studies were included, covering 18 countries. Among them, six nations (Austria, Bosnia and Herzegovina, Poland, Slovenia, the Czech Republic, and Germany) perform universal ultrasound screening. The timing of the first ultrasound varies, with Austria and the Czech Republic within the 1st week, Bosnia and Herzegovina on the day of birth, Poland between 1 and 12 weeks, and Germany before the 6th week. The Graf method is the most popular ultrasound technique used.

CONCLUSIONS

There is no consensus on the optimal DDH detection approach in Europe. Varied screening methods stem from epidemiological, cultural, and economic differences among countries.

Prediction of Late Dysplasia Based on Ultrasound and Plain X-Ray at 6 Months

BACKGROUND

Developmental dysplasia of the hip represents a spectrum of deformity. Residual dysplasia at 2 years of age is associated with an increased risk for osteoarthritis and functional limitations. We compared the prognostic value of 6-month imaging modalities and aimed to identify optimal diagnostic metrics for the prediction of residual dysplasia.

METHODS

After IRB approval, patients who underwent Pavlik treatment between 2009 and 2018 with 2-year follow-up were identified. Sonographs [ultrasound (US)] and radiographs (x-ray) were obtained at 6-month and 2-year-old visits. Dysplasia at 2 years was defined as an acetabular index (AI) >24 degrees. Receiver operating characteristic curves were constructed to quantitatively compare the prognostic ability of US and x-ray-based measures at 6 months. Youden's index [(YI) (values range from 0 (poor test) to 1 (perfect test)] was used to evaluate existing cutoffs at 6 months of age (normal measurements: alpha angle (AA) ≥60 degrees, femoral head coverage (FHC) ≥50%, and AI <30 degrees) relative to newly proposed limits.

RESULTS

Fifty-nine patients were included, of which 28.8% of patients (95% CI: 17.3 to 40.4%) had acetabular dysplasia at 2 years. After adjusting for sex, AA [Area under the Curve (AUC): 80] and AI (AUC: 79) at 6 months of age were better tests than FHC (AUC: 0.77). Current diagnostic cutoffs for AA (YI: 0.08), AI (YI: 0.0), and FHC (YI: 0.06) at 6 months had poor ability to predict dysplasia at 2 years. A composite test of all measures based on proposed cutoffs (AA ≥73 degrees, FHC > 62% and AI ≤24 degrees) was a better predictor of dysplasia at 2 years (Youden's index (YI): 0.63) than any single metric.

CONCLUSIONS

The rate of residual dysplasia remains concerning. The 6-month x-ray and US both play a role in the ongoing management of the developmental dysplasia of the hip. The prediction of dysplasia is maximized when all metrics are considered collectively. Existing parameters were not accurate; We recommend the following cutoffs: AA ≥73 degrees, FHC > 62%, and AI ≤24 degrees. These cutoffs must be validated.

LEVEL OF EVIDENCE

Prognostic Level II.