Developmental dysplasia of the hip. A population-based comparison of ultrasound and clinical findings

Clinical and ultrasound findings were compared in 3613 newborns examined for developmental dysplasia of the hip (DDH) within 48 hours of delivery. Clinical and sonographic hip stability was described as stable, borderline unstable, dislocatable or dislocated, and the morphology on ultrasound as normal, immature or dysplastic. Persistent clinical or sonographic dislocatability or dislocation. major dysplasia or minor dysplasia combined with an unstable femoral head were indications for early treatment. A total of 123 (3.4%) infants were subjected to early treatment. of which 55 (45%) fulfilled the criteria for treatment on both clinical and ultrasound examinations, 52 (42%) were treated on the basis of ultrasound findings alone, and 16 (13%) on the basis of clinical findings alone. Thirty percent of the infants with clinically dislocated or dislocatable hips were judged to have stable or just borderline unstable hips on the first clinical examination. Of 486 (13.5%) infants with sonographically immature or minor dysplastic but stable hips, 472 (97%) normalized spontaneously, while treatment was initiated in 14 (3%) of them at 1-3 months of age because of lack of sonographic improvement. Only one infant presented with late DDH during an observation period of 3 years. Accepting sonographic dysplasia as a criterion for early splinting may result in a treatment rate which is almost twice the rate based on clinical criteria, but late dislocation may be virtually eliminated.     

Developmental dysplasia of the hip in South Australia in 1991: Prevalence and risk factors

To determine the prevalence of developmental dysplasia of the hip (DDH) in South Australia (SA) in 1991, the proportion of cases detected in the neonatal period and the perinatal risk factors for DDH.

Methodology:

Cases of DDH born in SA in 1991 were identified from multiple sources and their clinical data linked to perinatal data provided by midwives; five controls per case were obtained randomly from SA livebirths without congenital abnormalities and adjusted odds ratios (OR) for potential risk factors obtained by logistic regression analysis. South Australia perinatal data were also used to estimate numbers of births with perinatal risk factors for targeted screening.

Results:

Two hundred and six cases of isolated DDH were identified, giving a prevalence of 10.5 per 1000 births. Of these, 173 (84%) had been detected in the neonatal period. The perinatal risk factors for DDH were identified as breech presentation (OR 9.65), female babies (OR 4.04), first births (OR 1.91) and maternal age of 25 years or more (OR 1.53). Screening breech and firstborn female babies (23% of births) would yield approximately 51% of cases of DDH.

Conclusions:

Isolated DDH had a prevalence of 10.5 per 1000 births and 84% of cases had been detected in the neonatal period in SA. Repeated screening during infancy of 'at risk' groups of babies is recommended.     

Screening for developmental dysplasia of the hip: Results of a 7-year follow-up study

BACKGROUND: Screening for developmental dysplasia of the hip (DDH) is widely recommended for all infants to prevent disability from late diagnosis of dislocation of the hip. The present study evaluates the results of screening for developmental dislocation of hip in a clinic in Turkey over the course of 7 years. METHODS: Hospital records of 5798 infants who were examined regularly until walking age at Gazi University well child clinics between January 1995 and December 2001 were reviewed. Infants with known risk factors for DDH such as breech presentation, family history of DDH or swaddling, and of infants with physical examination findings suggestive of DDH, were referred to orthopedic surgeons for diagnosis. Based on this final diagnosis, sensitivity, specificity, positive and negative predictive values of risk factors and physical examination findings were calculated. RESULTS: Of the 5798 infants, risk factors were detected in the medical history of 111 infants, and in 14 infants a musculoskeletal deformity was detected. In 606 infants the physical examination findings were suggestive of DDH. Ten patients were subsequently diagnosed with DDH. The sensitivity, specificity, positive predictive value and negative predictive values of having a risk factor for DDH in history were 10.0%, 98.1%, 0.9%, 99.8%, and having abnormal hip examination findings were 100.0%, 88.9%, 1.6% and 100.0%, respectively. CONCLUSIONS: A careful history and physical examination is the cornerstone of DDH screening. Serial hip examinations performed during health examination visits provide an opportunity to identify DDH cases. The sensitivity of risk factors in history and physical examination findings together is high enough to be accepted as a screening tool.     

Successful screening for neonatal hip instability in Australia

OBJECTIVE: Australian screening programmes for congenital dislocation of the hip (CDH) are characterized by lower neonatal hip instability (NHI) detection rates than more successful international programmes. Through creating a quality, accountable clinical screening programme for NHI detection, the present study aimed to establish the true incidence of NHI in Australian babies and to eliminate 'late diagnosed' CDH. METHODS: Doctors responsible for routine neonatal care were made accountable for NHI detection and examined 5166 consecutive live births in the first days of life between 1989 and 2000. Techniques for clinical NHI detection were taught, and doctors practised with teaching-mannequins. Paediatricians clinically determined true positive NHI cases and managed them for a 12-month period. Peer review of NHI detection rates was introduced to encourage accountability. Surveillance for 'late diagnosed' CDH occurred regularly through a variety of methods. RESULTS: One hundred babies with NHI were detected (19.4 per 1000): 77% were female; 26% were breech presentation, 25% had a family history of hip instability; and all received some form of splinting. Follow up for 85% of these babies at 12 months revealed no significant complications. Extensive searching has revealed no baby with 'late diagnosed' CDH from the study population in 12 years. One baby commenced treatment late (at 4 months) because of a failure of process following early NHI detection. CONCLUSIONS: The true incidence of NHI in Australia is > or =19 per 1000 births. Successful clinical CDH screening programmes using primary care doctors can be created and might eliminate 'late diagnosed' CDH.     

Perinatal risk factors for developmental dysplasia of the hip

AIMS—To identify perinatal risk factors for developmental dysplasia of the hip (DDH) and define the risk for each factor.METHODS—In this case control study, using logistic regression analysis, all 1127 cases of isolated DDH live born in South Australia in 1986-93 and notified to the South Australian Birth Defects Register were included; controls comprised 150 130 live births in South Australia during the same period without any notified congenital abnormalities.RESULTS—Breech presentation, oligohydramnios, female sex and primiparity were confirmed as risk factors for DDH. Significant findings were an increased risk for vaginal delivery over caesarean section for breech presentation (as well as an increased risk for emergency section over elective section), high birthweight (?4000 g), postmaturity and older maternal age; multiple births and preterm births had a reduced risk. There was no increased risk for caesarean section in the absence of breech presentation. For breech presentation, the risk of DDH was estimated to be at least 2.7% for girls and 0.8% for boys; a combination of factors increased the risk.CONCLUSIONS—It is suggested that the risk factors identified be used as indications for repeat screening at 6 weeks of age and whenever possible in infancy. Other indications are family history and associated abnormalities.     

Value of limited hip abduction in developmental dysplasia of the hip

BACKGROUND: Developmental dysplasia of the hip (DDH) continues to be missed by routine physical examination in up to 50% of cases. Ultrasound (US) supplementation is the best method of screening for DDH, but the resources required should not be underestimated. Limited abduction of the hip (LHA) in an infant triggers suspicion, and often an urge to treat, in most orthopaedic surgeons and pediatricians alike. This study aimed to document the value of unilateral LHA in the diagnosis and decision making of DDH, and the correlation between LHA and US. METHODS: In total, 464 infants referred from the pediatrics clinic with LHA, aged between 30 and 120 days, were included in the study. RESULTS: Physical examination revealed LHA in 186 (41%) infants, 26 of which were unilateral and 160 were bilateral. US examination showed that 13 (8.1%) patients in the bilateral LHA group and 18 (69.2) patients in the unilateral LHA group, had DDH (total number 31, 7%). CONCLUSION: Unilateral limitation of hip abduction was found to be a sensitive sign for developmental hip dysplasia, but US could be defined once again as the best golden standard before initiating treatment.     

Differences in risk factors between early and late diagnosed developmental dysplasia of the hip

BACKGROUND: Developmental dysplasia of the hip (DDH) is common, affecting 7.3 per 1000 births in South Australia. Clinical screening programmes exist to identify the condition early to gain the maximum benefit from early treatment. Although these screening programmes are effective, there are still cases that are missed. Previous research has highlighted key risk factors in the development of DDH. OBJECTIVE: To compare the risk factors of cases of DDH identified late with those that were diagnosed early. METHODS: A total of 1281 children with DDH born in 1988-1996 were identified from the South Australian Birth Defects Register. Hospital records of those who had surgery for DDH within 5 years of life were examined for diagnosis details. Twenty seven (2.1%) had been diagnosed at or after 3 months of age and were considered the late DDH cases (a prevalence of 0.15 per 1000 live births). Various factors were compared with early diagnosed DDH cases. RESULTS: Female sex, vertex presentation, normal delivery, rural birth, and discharge from hospital less than 4 days after birth all significantly increased the risk of late diagnosis of DDH. CONCLUSIONS: The results show differences in the risk factors for early and late diagnosed DDH. Some known risk factors for DDH are in fact protective for late diagnosis. These results highlight the need for broad newborn population screening and continued vigilance and training in screening programmes.     

发育性髋关节发育不良儿童髋臼形态学病理分型的探讨

目的通过三维CT分析髋臼形态学的病理改变,为临床选择合适的骨盆截骨方式提供参考。方法选择101例发育性髋关节发育不良儿童,共129个髋关节。术前行髋关节螺旋CT扫描并通过Mimics 10.01软件进行三维重建,根据以往参考文献分型,结合病例观察,提出髋臼形态学病理分型。结果分为六型:Ⅰ型为轻度发育不良,占31.8%。Ⅱ型为髋臼前上缺损,占17.1%。Ⅲ型为中上缺损,占32.6%。Ⅳ型为全缺损,占10.8%。Ⅴ型为假臼,占5.4%。Ⅵ型为三角型髋臼,占2.3%。结论髋臼形态学新的病理分型有助于对发育性髋关节发育不良儿童病理改变的认识。通过三维CT了解髋臼的不同形态学改变,能为临床选择合适的骨盆截骨方式提供参考。     

Neonatal hip instability: results and experiences from ten years of screening with the anterior-dynamic ultrasound method

AIM: To record the results and experiences from a 10-y screening period with the anterior-dynamic ultrasound method for detecting neonatal hip instability. METHODS: An ultrasonographic improvement of the Palmén/Barlow test was used. The screening programme included 22,047 newborns. Decisions about treatment were made solely on the ultrasound result. RESULTS: It was found that 175 infants (7.9/1000) had at least one unstable hip--dislocated or dislocatable. Dislocated hips were found in 1.1/1000. Dislocatable hips were found in 6.8/1000 but only 1.1/1000 needed treatment. The total frequency of treatment was 2.2/1000. All cases but one were diagnosed before discharge from the maternity ward. The rate of surgery was 0.1/1000 newborns. Girls were more affected than boys, by a ratio of 3:1. Among the affected hips 64.4% were a left hip. CONCLUSION: Neonatal hip instability is always present at birth and can be diagnosed immediately after birth. We have no indications that instability can appear at a later stage. The anterior-dynamic ultrasound screening programme is an efficient tool to diagnose neonatal hip instability and to decide when to begin treatment.     

Management of neonatal hip instability and dysplasia

The diagnosis and treatment of neonatal hip instability and dysplasia is controversial. Different countries have different algorithms and guidelines on which hips should be screened or treated. German speaking countries have introduced universal ultra sound hip screening programmes resulting in relatively high splintage rates in certain centres. Some Scandinavian centres have organised selective screening programmes with serial ultrasound observation of hip instabilities, leading to comparatively low splintage rates. Though most experts would treat clinical hip instability (confirmed by ultrasound evaluation), the natural history and epidemiology of dysplasia is less well understood. The treatment regimes for neonatal dysplasia are varied with wide differences in the rates of splintage. 'Late' dislocation may be secondary to prenatal dislocation (teratogenic), neonatal hip instability or to persistent major dysplasia of the hip. The term 'missed' dislocation should not be used as this suggests negligence on the part of the examiner, when this may not be the case. Which splint to use (rigid or dynamic), at what age, and for how long, are questions currently unresolved as no proper controlled trials have been undertaken. However, a sensible treatment algorithm can be advocated. Complications secondary to splintage are rare, though nerve damage, avascular necrosis of the hip, redislocation and skin problems have been described.     

髋发育不良数字声波技术的早期筛查价值

目的：开发一种非侵入性数字声波技术，反映髋关节的结构特征，用于新生儿髋发育不良的早期筛查，方法：应用包括有刺激系统、传导系统和带有双通道数字过滤程序数据分析系统的数字声波技术，测量分析了90例正常新生儿两侧髋关节声波信号相关性（CF）和声强差异（D），并初步对16例1－60岁月婴幼儿进行相应测量，并对正常组进行比较。结果：在160－315Hz范围，两侧髋关节声波信号相关性；正常组CF＞0．94，髋发育不良组中有6例CF＜0．8，声强差异；正常组D＜2dB；髋发育不良组均明显大于正常，差异有显著性意义（P＜0．001）。统计学处理还表明，以声强差异2dB为临界点，灵敏可以达到100％。结论：该声波技术提供了一个用数字客观评估髋关节声波信号的实用方法，可于新生儿髋发育不良的早期筛查。     

Treatment and prevention of hip dysplasia in infants and young children

The diagnosis and treatment of developmental dysplasia of the hip in the infant are uniform, with consensus that diagnostic ultrasound and Pavlik harness management are standard procedures. Sequential procedures for failed early treatment, residual dysplasia and late diagnosis are dependent on the age and the severity of the dysplasia.     

Ultrasonographic evaluation of breech presentation as a risk factor for hip dysplasia

In order to gain more information of breech position as a risk factor for congenital hip dysplasia or dislocation, the hips of 408 newborns delivered in the breech position were examined by ultrasound. Clinical examination was performed by both experienced paediatricians and orthopaedic surgeons. The infants were re-examined by ultrasound at 2–3 months of age. Twenty-five newborns (6.1%) had neonatal hip instability. Breech presentation as a risk factor was confirmed, with first borns, breech position with extended knees, and high birthweight as special high-risk groups. Ultrasound showed subluxation in most of the unstable hips. The main benefit of using ultrasound was that direct visualization permitted more reliable evaluation, especially when the clinical findings were uncertain. Normal ultrasound findings in false positive and uncertain Ortolani tests reduced the frequency of unnecessary treatment. Because ultrasound was used in follow-up, the need of radiography was reduced. There were no late-detected cases of hip dysplasia or dislocation, indicating that routine follow-up is not necessary in breech infants with normal hips at birth, provided that the neonatal screening is optimal.     

Whole genome SNP genotyping in a family segregating developmental dysplasia of the hip detected runs of homozygosity on chromosomes 15q13.3 and 19p13.2

Developmental dysplasia of the hip (DDH) is one of the most prevalent developmental orthopedic diseases worldwide. DDH is a spectrum of anatomical abnormalities of the hip joint and is characterized by premature arthritis in later life. Sporadic cases have been reported more frequently; however, some studies have reported families segregating DDH. Studies have suggested that the genetic factors play a significant role in the development of DDH. In order to detect genetic defect underlying DDH, we performed Sanger sequencing of all DDH associated genes, whole genome SNP genotyping and exome sequencing in a Saudi family with four individuals having DDH. Sanger sequencing of all known genes did not identify any pathogenic variant. Genotype data analysis using HomozygosityMapper identified shared homozygous regions on chromosome 15q13.3 and chromosome 19p13.2 flanked by rs17228178‐rs1534200 and rs466123‐rs2112461, respectively. These data were also analyzed by cnvpartition software for identification of DDH associated copy number variations (CNV). A shared copy number gain of approximately 15 kb on chr6p21.32 (chr6:33 053 906–33 069 893) was discovered in all affected individuals. Partial gain of this region has also been found in unaffected sibling of this family. Exome data did not reveal any candidate sequence variant. Whole genome sequencing is required to identify deep intronic variants in the shared homozygous regions. Identification of genetic variants involved in pathogenesis of DDH may open up interesting perspectives into the function of the gene(s) in hip joint development.     

Screening for hip abnormality in the neonate

Clinical screening policies for the detection of hip instability or dysplasia of the hip vary internationally. There is general agreement in the Western world that at birth all hip joints should be clinically assessed by the Ortolani and Barlow tests. Currently, there is no consistency regarding who should undertake the examination, the results being worse when inexperienced personnel are used. These clinical tests have poor sensitivity and should be regarded as surveillance, not screening methods. Since the 1980s ultrasonographic assessment of the hip has become a valuable diagnostic tool. However there is continuing controversy on whether this imaging method should be used universally or selectively for 'at risk' and clinically unstable hip joints. Universal ultrasonographic evaluation may result in over-treatment and selective screening may be no better than the best clinical screening programs in reducing the incidence of 'late' irreducible dislocation of the hip. It is generally accepted that all clinically unstable hips should be imaged by ultrasound by static and dynamic methods in order to confirm the diagnosis and to monitor treatment.