Aims

The aim of this prospective cohort study was to evaluate the effectiveness of the neonatal hip instability screening programme.

A prospective neonatal screening programme for congenital dislocation of the hip is reported. This covered over 20,000 live births including all the babies born in one area, with a virtually complete follow-up. All babies were examined within the first seven days of life and all hips which were dislocated or unstable after four days (1.6%) were splinted. Only two screened cases were "missed" and subsequently detected at 15 and 18 months. No later cases were discovered, and patients between 10 and 20 years of age had apparently remained asymptomatic. The detailed results show that neonatal screening is effective in detecting and preventing a crippling disorder in otherwise normal people. The examination, though brief, is difficult to perform well; it is considered that failure of the method lies with the examiner and not with the tests.

Over a 15-year prospective period, 201 infants with a clinically unstable hip at neonatal screening were subsequently reviewed in a ‘one stop’ clinic where they were assessed clinically and sonographically. Their mean age was 1.62 weeks (95% confidence interval (CI) 1.35 to 1.89). Clinical neonatal hip screening revealed a sensitivity of 62% (mean, 62.6 95%CI 50.9 to 74.3), specificity of 99.8% (mean, 99.8, 95% CI 99.7 to 99.8) and positive predictive value (PPV) of 24% (mean, 26.2, 95% CI 19.3 to 33.0). Static and dynamic sonography for Graf type IV dysplastic hips had a 15-year sensitivity of 77% (mean, 75.8 95% CI 66.9 to 84.6), specificity of 99.8% (mean, 99.8, 95% CI 99.8 to 99.8) and a PPV of 49% (mean, 55.1, 95% CI 41.6 to 68.5). There were 36 infants with an irreducible dislocation of the hip (0.57 per 1000 live births), including six that failed to resolve with neonatal splintage.

Most clinically unstable hips referred to a specialist clinic are female and stabilise spontaneously. Most irreducible dislocations are not identified from this neonatal instability group. There may be a small subgroup of females with instability of the hip which may be at risk of progression to irreducibility despite early treatment in a Pavlik harness.

A controlled study is required to assess the value of neonatal clinical screening programmes.

Cite this article: Bone Joint J 2015;97-B:265-9.

Since September 1964, neonates born in New Plymouth have undergone clinical examination for Neonatal Instability of the Hip (NIH) in a structured clinical screening programme. Forty one thousand, five hundred and sixty three babies were born during the period of this study, of which 1,638 were diagnosed as having unstable hips. Six hundred and thirty three with persisting instability were splinted (1.6%), with five hips failing splintage. In addition, three unsplinted hips progressed to CDH, and there were four late-presenting (walking) cases of CDH, giving an overall failure rate for the programme of 0.29 per 1000 live births, with a late-presenting (walking) CDH incidence of 0.1 per 1000 live births. This study confirms that clinical screening for NIH by experienced orthopaedic examiners significantly lowers the incidence of late-presenting (walking) CDH.

Purpose

There is concern that the positive predictive value (PPV) of neonatal screening for instability may have deteriorated over recent years, this study aims to evaluate this.

The purpose of this study was to audit screening and treatment programmes for Developmental Dysplasia of the Hip (DDH) over a 12-year period from 1989 to 2000 with respect to late presentation and treatment rate and duration.

All babies born in Queen Mary Hospital are clinically screened for DDH by a consultant orthopaedic surgeon. Unstable hips are treated by Pavlik Harness and attend an ultrasound clinic run by an orthopaedic surgeon within 2 weeks. High-risk babies or those with suspected instability can also be referred for ultrasound. Serial ultrasound exams assisted with determining the duration of splintage. Radiographs are taken at 4 to 6 months. Late presenters were identified and analysed.

Over the 12-year period 13 cases of late presenting DDH were identified (0.6 per 1000). Half of these had not been screened. None had ultrasound screening. Our treatment rate was approximately 4 per 1000 live births.

Our screening programme can be improved by increased capture of patients for clinical screening. Ultrasound is a useful tool in managing neonatal hip instability allowing duration of splintage to be tailored to the individual and allows early detection of treatment failure.

The incidence of DDH Varies depending on genetic and ethnic varieties but in Ireland on an average in 3 per 1,000 live births. Current treatment is focused on early diagnosis and congruent reduction of the hip joint. With conservative measures, principally skilful use of the Pavlik harness, the majority of (85%) of dislocated or subluxated hips will be successfully treated. Late diagnosis impacts on the mode of treatment and on the subsequent outcome.

An audit of annual incidence of DDH in North Eastern health board, in Ireland showed a dramatic increase in late diagnosis (> 4 month). There were 4668 live births in 2004 with 17 cases of DDH presenting between the ages of 4 – 36 months during this period. The mean age of presentation was 10 months. Two cases were bilateral. The male: female ratio was 4.6:1. Risk factor analysis showed, only 50% fell in to the high risk group, majority of them had positive family history. Three fourth of them were frank dislocations and all of them required operative intervention. As opposed to early presenters, only 10% needed operative intervention. 30% of the late presenters needed major osteotomies.

We examined the reasons for this extreme high rate of late presenters and argue for the introduction of routine ultrasound screening in this region based on historical high incidence of DDH and the dramatic incidence of delayed diagnosis.

Twins are often considered to be at an increased risk of developmental dysplasia of the hip (DDH); we therefore investigated whether multiple births have a higher incidence of DDH, and if selective ultrasound scanning should be considered for these infants.

We reviewed our records of all live births between 1 January 2004 and 31 December 2008 and included 25 246 single and 990 multiple births.

Multiple births did not have a significantly higher incidence of DDH compared with single births (0.0030 vs 0.0023, p = 0.8939). Of the 990 multiple births, 267 had neonatal ultrasound scans and one case of DDH was diagnosed and treated successfully with a Pavlik harness. There were two late-presenting cases at eight and 14 months of age, neither of whom had risk factors for DDH and consequently had not had a neonatal scan. Whereas selective ultrasound scanning of multiple births would have led to earlier detection and treatment of the late-presenting cases, they did not have a significantly higher incidence of DDH compared with single births.

We conclude that being a twin or triplet in itself is not a risk factor for DDH and that selective ultrasound scanning is not indicated for this population.

Cite this article: Bone Joint J 2013;95-B:132–4.

The treatment of developmental dysplasia of the hip diagnosed after the first year of life remains controversial. A series of 36 children (47 hips), aged between one and 4.9 years underwent gradual closed reduction using the Petit-Morel method. A pelvic osteotomy was required in 43 hips (91.5%). The patients whose hips did not require pelvic osteotomy were among the youngest. The mean age at final follow-up was 16.1 years (11.3 to 32). The mean follow-up was 14.3 years (10 to 30).

At the latest follow-up, 44 hips (93.6%) were graded as excellent or good according to the Severin classification. Closed reduction failed in only two hips (4.3%) which then required open reduction. Mild avascular necrosis was observed in one (2.1%).

The accuracy of the reduction and associated low complication rate justify the use of the Petit-Morel technique as the treatment of choice for developmental dysplasia of the hip in patients aged between one and five years.