Genetic Predisposition to Developmental Dysplasia of the Hip.

BACKGROUND: The etiopathogenesis of developmental dysplasia of the hip (DDH) has not been clarified. This systematic review evaluated current literature concerning all known chromosomes, loci, genes, and their polymorphisms that have been associated or not with the prevalence and severity of DDH. METHODS: Following the established methodology of Meta-analysis of Observational Studies in Epidemiology guidelines, MEDLINE, EMBASE, and Cochrane Register of Controlled Trials were systematically searched from inception to January 2019. RESULTS: Forty-five studies were finally included. The majority of genetic studies were candidate gene association studies assessing Chinese populations with moderate methodological quality. Among the most frequently studied are the first, third, 12th,17th, and 20th chromosomes. No gene was firmly associated with DDH phenotype. Studies from different populations often report conflicting results on the same single-nucleotide polymorphism (SNP). The SNP rs143384 of GDF5 gene on chromosome 20 demonstrated the most robust relationship with DDH phenotype in association studies. The highest odds of coinheritance in linkage studies have been reported for regions of chromosome 3 and 13. Five SNPs have been associated with the severity of DDH. Animal model studies validating previous human findings provided suggestive evidence of an inducing role of mutations of the GDF5, CX3CR1, and TENM3 genes in DDH etiopathogenesis. CONCLUSION: DDH is a complex disorder with environmental and genetic causes. However, no firm correlation between genotype and DDH phenotype currently exists. Systematic genome evaluation in studies with larger sample size, better methodological quality, and assessment of DDH patients is necessary to clarify the DDH heredity. The role of next-generation sequencing techniques is promising.

Do we need to follow up an early normal ultrasound with a later plain radiograph in children with a family history of developmental dysplasia of the hip?

BACKGROUND: We routinely perform a pelvic radiograph between 6 and 12 months of age for children with a family history of developmental dysplasia of hip (DDH). We conducted this study to determine whether children with a family history of DDH and a normal hip ultrasound after birth require any further radiological follow-up. METHODS: We identified all children referred to our hip-screening clinic in a 3-year period between August 2008 and August 2011 with a family history of DDH and a normal hip ultrasound after birth. A total of 119 patients with a normal hip ultrasound after birth had a pelvic radiograph at a median age of 6.6 months. RESULTS: Six patients had residual dysplasia (acetabular index >30°) on the initial radiograph; five of these had resolved spontaneously by age 12 months, and the remaining patient had a normal radiograph at 21 months of age and was discharged. CONCLUSION: We have found no cases of residual hip dysplasia requiring treatment in children with a family history of DDH and a normal hip ultrasound after birth. We have therefore changed our practice accordingly and no longer routinely followed up such cases. LEVEL OF EVIDENCE: Diagnostic study, Level II.

Pelvic osteotomies in hip dysplasia: why, when and how?

Acetabular dysplasia is a significant problem in the spectrum of developmental dysplasia of hip. In a younger child, positioning the femoral head into the acetabulum helps in reciprocal remodeling of the acetabulum and correction of dysplasia. In an older child, the remodeling potential is limited and often the acetabular dysplasia needs surgical intervention in the form of a pelvic osteotomy. Thus, pelvic osteotomy forms an integral part of surgical management of hip dysplasia. The ultimate goal of these osteotomies is to preclude or postpone the development of osteoarthritis and add more years of life to the native hip. Pelvic osteotomies play a pivotal role in normalizing hip morphology. The choice of pelvic osteotomy depends on the age of a child, the type of dysplasia and the status of the tri-radiate cartilage. Several types of re-directional and reshaping pelvic osteotomies have been described in the literature to improve the stability and restore the anatomy and biomechanics of the dysplastic hip. This article attempts to review the current indications for various pelvic osteotomies with a brief description of their techniques along with the outcomes and complications published thus far. Besides, the guidelines to choose the right pelvic osteotomy are also provided.

Evaluation of Acetabular Development Following Open Reduction of Developmental Dysplasia of Hip in Children After Walking Age.

BACKGROUND AND PURPOSE: The growth and development of the acetabulum in children with developmental dysplasia of hip (DDH) depends upon the extent of concentric reduction. Children in walking age often need open reduction with or without additional osteotomies to obtain congruous, stable reduction. The purpose of this study was to evaluate acetabular development in late diagnosed DDH treated by open reduction with or without femoral osteotomy. METHODS: This is a retrospective study of 29 children (40 hips) with idiopathic DDH, previously untreated managed by open reduction with or without femoral osteotomy. We analyzed preoperative and yearly postoperative radiographs up to 6 years of age for acetabular development by measuring acetabular index. Acetabular remodeling was assessed with a graphical plot of serial mean acetabular index. Those with AI < 30° at outcome measure point of 6 years of patient age were considered to have satisfactory acetabular remodeling. RESULTS: Mean age of surgery was 26.8 months. Open reduction alone was done in 14 hips and open reduction with concurrent femoral osteotomy done in 26 hips. The mean acetabular index pre operatively was 36.6° ± 5.9° which reduced to 29.7° ± 6° at 1-year follow-up and to 26.6° ± 5.9° at 2-year follow-up. 28 out of 40 hips were available for evaluation at outcome measure point of 6 years of age, which showed satisfactory remodeling in 24 hips with mean AI of 22.7° ± 5.7°. Maximum acetabular development was seen at 2 years post-surgery and better remodeling was seen in children operated at less than 2 years of age. 5 hips had changes of avascular necrosis of femoral head. There was no incidence of redislocation/subluxation at latest follow-up. CONCLUSION: Open reduction in late-diagnosed developmental dysplasia of hip has potential for favourable acetabular development. Femoral osteotomy when required along with open reduction may suffice to address acetabular dysplasia found in the initial years of management of DDH.

Influence of experience on intra- and inter-observer reproducibility of the Crowe, Hartofilakidis and modified Cochin classifications.

INTRODUCTION: A previous study demonstrated that the reproducibility of the Crowe (Cr), the Hartofilakidis (Ha) and the modified Cochin (Co) classifications were comparable. However, there were differences with a trend that suggested the influence of experience. Therefore, we performed a prospective study to investigate whether experience influenced the reproducibility of the commonly used developmental dysplasia of the hip (DDH) classifications. HYPOTHESIS: The hypothesis was that the intra- and inter-observer reproducibility scores would be higher in the senior group than the junior group, and particularly for the modified Co classification. METHODS: Four seniors and four residents classified 104 A/P pelvic radiographs (200 hips) two times using the Cr, Ha and Co classification systems. RESULTS: For intra-observer reproducibility, the average weighted concordance coefficients [95% confidence intervals] were for the senior and the junior groups: 92.2 [88.6-95.7] and 92.6 [87.9-97.2] for Cr, 92.1 [88.7-94.6] and 92.0 [87.7-96.3] for Ha, 94.2 [91.8-96.6] and 94.1 [91.5-96.6] for Co. The average weighted Kappa (95% confidence intervals) were 0.8 [0.71-0.88] and 0.79 [0.68-0.89] for Cr, 0.77 [0.74-0.81] and 0.75 [0.62-0.88] for Ha, 0.82 [0.76-0.89] and 0.80 [0.74-0.87] for Co. The junior inter-observer reproducibility multi-rater Kappa (list A:list B) were 0.57:0.50 (Cr), 0.47:0.53 (Ha), 0.42:0.42 (Co). Senior multi-rater Kappa were 0.53:0.49 (Cr), 0.40:0.34 (Ha), 0.40:0.43 (Co). CONCLUSIONS: Contrary to our hypothesis, the experience of the observer did not affect the intra- and inter-observer reproducibility of the three classification systems.

Spica magnetic resonance imaging for determination of abduction angle: initial results and reproducibility assessment.

PURPOSE: Spica magnectic resonance imaging (MRI) is an established technique for postoperative determination of hip reduction in patients treated for developmental dysplasia of the hip (DDH). A hip abduction angle >55° is considered excessive and has been associated with epiphyseal osteonecrosis. Our purpose was to establish objective criteria for measuring hip abduction angles on MRI after hip reduction and spica casting in patients with DDH, and evaluate reproducibility and reliability of angle measurement using these criteria. METHODS: Forty patients with DDH at our institution who underwent spica MRI after hip reduction between 3 April 2008 and 3 March 2015 were identified. Hip abduction angles were measured on proton density axial images as follows. A transverse line was drawn connecting the posterior ischial tuberosities. A second line was drawn medially along the distal femoral diaphysis, and the angle between these two lines was measured; this value was subtracted from 90°, yielding the degree of abduction from midline. Measurements were independently performed by three faculty radiologists, one orthopedist, and one radiology resident. Inter-reader and intra-reader reliability was assessed using intraclass correlation (ICC), with 0 representing no agreement and 1 representing perfect agreement. RESULTS: For inter-reader reliability, the ICC of the five physicians was 0.89 (95 % CI 0.84-0.92). For intra-reader reliability, the ICC of the five physicians ranged from 0.90-0.97 (95 % CI 0.85-0.98). The mean standard deviation of hip abduction angle measurement among readers was 3.6°. CONCLUSION: The proposed hip abduction angle measurement criteria for spica MRI are both reproducible and easy to perform. The high ICC and low standard deviation of independently evaluated hip abduction angles indicates high reproducibility of measurement. This applies to both inter- and intra-reader reliability.

Cementless arthroplasty with a distal femoral shortening for the treatment of Crowe type IV developmental hip dysplasia.

BACKGROUND: Severe developmental dysplasia of the hip is a surgical challenge. The purpose of this study is to describe the cementless arthroplasty with a distal femoral shortening osteotomy for Crowe type IV developmental hip dysplasia and to report the results of this technique. MATERIALS AND METHODS: 12 patients (2 male and 10 female) of Crowe type IV developmental hip dysplasia operated between January 2005 and December 2010 were included in the study. All had undergone cementless arthroplasty with a distal femoral shortening osteotomy. Acetabular cup was placed at the level of the anatomical position in all the hips. The clinical outcomes were assessed and radiographs were reviewed to evaluate treatment effects. RESULTS: The mean followup for the 12 hips was 52 months (range 36-82 months). The mean Harris hip score improved from 41 points (range 28-54) preoperatively to 85 points (range 79-92) at the final followup. The mean length of bone removed was 30 mm (range 25-40 mm). All the osteotomies healed in a mean time of 13 weeks (range 10-16 weeks). There were no neurovascular injuries, pulmonary embolism or no infections. CONCLUSION: Our study suggests that cementless arthroplasty with a distal femoral shortening is a safe and effective procedure for severe developmental dysplasia of the hip.

Evidence-based management of developmental dysplasia of the hip.

Developmental Dysplasia of the Hip (DDH) refers to a spectrum of abnormalities involving the developing hip. These abnormalities range from mild instability to frank dislocation of the joint. It is important to treat the condition effectively in order to encourage the hip to develop normally and produce good long-term results. This article reviews the evidence related to the treatment of DDH. The quality of evidence for DDH management remains low, with little uniformity in terminology and most studies being retrospective in nature. Given this, it is not possible to recommend or reject most treatment modalities based on existing studies.

The incidence of avascular necrosis and the radiographic outcome following medial open reduction in children with developmental dysplasia of the hip: a systematic review.

The incidence of clinically significant avascular necrosis (AVN) following medial open reduction of the dislocated hip in children with developmental dysplasia of the hip (DDH) remains unknown. We performed a systematic review of the literature to identify all clinical studies reporting the results of medial open reduction surgery. A total of 14 papers reporting 734 hips met the inclusion criteria. The mean follow-up was 10.9 years (2 to 28). The rate of clinically significant AVN (types 2 to 4) was 20% (149/734). From these papers 221 hips in 174 children had sufficient information to permit more detailed analysis. The rate of AVN increased with the length of follow-up to 24% at skeletal maturity, with type 2 AVN predominating in hips after five years' follow-up. The presence of AVN resulted in a higher incidence of an unsatisfactory outcome at skeletal maturity (55% vs 20% in hips with no AVN; p < 0.001). A higher rate of AVN was identified when surgery was performed in children aged < 12 months, and when hips were immobilised in ≥ 60° of abduction post-operatively. Multivariate analysis showed that younger age at operation, need for further surgery and post-operative hip abduction of ≥ 60° increased the risk of the development of clinically significant AVN.

Pathogenic risk factors correlation study of developmental dysplasia hip in Shigatse of Tibet / 中华实用儿科临床杂志

Objective To perform the epidemiological analysis of the developmental dysplasia hip(DDH) in Shigatse of Tibet in order to explore the correlation between the onset of DDH with some risk factors such as altitude and take targeted intervention measures to reduce the disability rate of DDH.Methods A total of 5900 children aged 0 to 14 year-old from different altitudes in Shigatse of Tibet were surveyed randomly from June 2013 to June 2014.SPSS 18.0 statistical software was used to analyze the correlation of the onset of DDH with residence altitude,production and living ways,binding method of the lower limbs,delivery situation and genetic factor.Results One hundred and ninety-one DDH cases were screened out,and the average incidence of DDH in Shigatse of Tibet was about 32.4‰,and unilateral was higher than bilateral,fight side(33 cases)∶left side(68 cases) =1.00∶ 2.06.The result of Pearson correlation analysis of the onset of DDH with residence altitude showed that there was significant correlation (r=0.820,P=0.046).The result of Spearman correlation analysis of the onset of DDH with production and living ways showed that there was significant correlation(r=0.530,P =0.048).The result of x2 test analysis of the onset of DDH with binding method of the double lower limbs and breech delivery showed that there was statistical significance (P=0.0017,0.0082).Conclusions The DDH incidence of children living in high altitude areas in Tibet has certain regional characteristics indicating that it has clear correlation with some environmental risk factors such as altitude,methods of the lower limbs binding,production and living ways and breech delivery,especially the bundled package of lower limbs is the main environmental risk factor of DDH.

Treatment with total hip arthroplasty using Zweym?ller system for female Crowe-Ⅲ and Ⅳ developmental dysplasia hip / 中国矫形外科杂志

[Objective] To evaluate the treatment with total hip arthroplasty(THA)using Zweym?ller system for short females with Crowe-Ⅲ and Ⅳ developmental dysplasia hip(DDH).[Method]From January 2004 to December 2006,thirteen THA procedures were performed in 12 female patients with 13 hips.The age of the patients was from 28 to 62 years old(average 51 years).The height was from 1.48 to 1.55 meters.Based on Crowe classification,8 patients with 9 hips were type-Ⅲ,and 4 patients with 4 hips were type-Ⅳ.before surgery,the discrepancy of lower limbs was from 3 cm to 5 cm.All patieds had severe hip pain and dysfunction.The Harris hip score ranged from 35 to 64 points with 40 points on the average.In all procedures the soft tissue was released entirely,the acetabular component was placed in the true acetabulum without femoral osteotomy.[Result]After operation,the legs lengthened from 2 to 5 cm.During the follow-up of 12 to 36 months(average 24 months),no femoral fracture,femoral or sciatic nerve palsy or loosening was detected except one dislocation according to clinical outcomes and X-ray findings.The Harris score was improved from 60 to 95.There was significant difference between before and after operation(P