To determine the incidence of congenital hip dislocation (CDH) a retrospective study was carried out of cases occurring in a defined population using multiple information sources. Of 138 600 children born in the period 1983-1987, a total of 243 were diagnosed with CDH, defined as those requiring splintage or surgery whose treatment extended beyond 6 months of age. Incidence and estimates of relative risks for pre-disposing factors were determined. The rate was 1.75 cases per 1 000 livebirths. Major risk factors were female gender and breech presentation. The proportions of cases identified before 1, 3 and 6 months of age were 8, 14 and 35%, respectively. Despite using a restrictive definition, we have obtained an incidence rate among the highest reported in any United Kingdom population. Early detection is widely accepted as desirable, but neonatal screening has proved ineffective.

Congenital dislocation of the hip (CDH) affects two children per 1000, with potentially serious consequences. Student health visitors in Northern Ireland learn screening techniques for CDH at a half-day workshop at a regional hospital. In order to evaluate the adequacy of this preparation, 71 qualified health visitors were surveyed to assess their knowledge relating to CDH, their views on the adequacy of the training, and their opinions about referral of positive cases. Knowledge in some areas was poor and preparation was considered too short. Direct referrals of positive cases to orthopaedic clinics, without a general practitioner acting as an intermediary, was a frequently cited desire. Recommendations include extending the training for those involved in CDH screening while ensuring that experienced health visitors, from whom novices learn, are themselves using correct procedures.

To investigate if those responsible for screening for neonatal hip instability are using acceptable manual hip stress tests as described by Ortolani and Barlow. A video camera was used to record the technique of 35 personnel who were responsible for screening. They examined both a baby and a simulator. The study comprised five groups, classified by experience and practice: senior orthopaedic surgeons, senior paediatric staff, junior paediatric staff, nurses, community staff. The seven authors together with six independent expert observers viewed the video and marked the performance with the aid of a specially designed proforma. Although there was some variation between these expert observers, the results showed differences in the scores obtained by the different groups of examiners over all aspects of the test procedure. Video recording for criticalanalysis and feedback is a useful technique in this situation. Overall, the results suggest that testing for neonatal hip instability was inadequate. A variety of hip stress manoeuvres were being performed. The ability of each subject to perform satisfactory tests seemed to depend on their experience and education. More “hands on” training and experience of testing might provide the necessary competency for screening.

Developmental dysplasia of the hip (DDH) is a term used to describe a group of disorders of the neonatal hip in which the head of the femur is unstable or incongruous in relation to the acetabulum. Early detection and treatment of the condition generally results in normal development, whereas late diagnosis has poor success. In Northern Ireland, despite all neonates being manually examined for hip disorders by a medical officer before hospital discharge, there is an unacceptable late diagnostic rate of almost 50% of all cases. To help reduce the number of late presentations, vibration arthrometry, a noninvasive form of screening for DDH, has been used to record hip vibration events during clinical testing. In a comparative study, 300 infants were examined by nurses and medical officers to establish the sensitivity of manual palpation to neonatal hip vibrations detected by the objective detection system. Experienced research nurses detected 86% of the signals; doctors in training detected less than 10%. This suggests that objective, noninvasive screening by vibration arthrometry would detect a higher proportion of vibration events in neonates during the early stages of DDH. More time should be invested in training medical officers and others involved in DDH screening.

Hip dislocation remains the most significant childhood orthopaedic abnormality despite the efforts of neonatal screening, first described in 1910. A new method of enhancing the performance of screening, the Belfast hip screener, is a non-invasive device developed to detect and interpret the vibrations ("clicks" and "clunks") which are emitted as the hips are physically tested. A progress report is presented covering ten years' work from early records made with tape recorders to modern methods of digital signal processing.