EPIDEMIOLOGY OF CONGENITAL HIP DISPLACEMENT: PROSPECTIVE ANALYSIS OVER 20 YEARS

Abstract

Purpose: The prognosis of congenital hip displacement basically depends on the time of diagnosis and treatment. Recognising high-risk hips early remains a number one priority. We conducted a prospective study over a 20-year period from 1992 to 2002 to analyse the epidemiology of congenital hip displacement.

Material and methods: The series included 1056 children with congenital hip disease (1491 hips). Epidemiological data, ultrasound and x-ray findings were recorded over 20 years. The objective was to identify risk factors and evaluate the impact of prevention measures.

Results: The sex ratio showed female predominance, 6:1. The left hip was involved 1.8 times more often, with 41% bilateral involvement. Risk factors were major: family history (31%), breech presentation (25%), postural syndrome (12%); or minor: primiparity (54.4%), birth weight > 4 kg (9.2%). One or more major risk factors were found in 60.5% of the children and 30% had at least one minor risk factor. No risk factor was found in 40%. Screening efficacy improved with a rate of diagnosis before 4 months of 59% in 1983 and 96% in 2002. The number of hips discovered after the age of one year was 15% in 1983 and 6% in 2002.

Discussion: The severity of the hip displacement is not influenced by risk factors nor bilateral involvement. Screening has enabled earlier diagnosis with a 37% increase in the rate of identification before the age of four months. This has been made possible by a systematic examination at birth and ultrasonography introduced in 1989.

Conclusion: A regional map showing the paediatrician : maternity : general practitioner distributions is an important tool for screening campaigns. Despite adequate screening 40% of these children do not have any risk factor. Repeated examinations, communication and information exchange between healthcare professionals are the keys to success.