Hip arthrography in the assessment of children with developmental dysplasia of the hip and Perthes' disease

In our unit, children with developmental dysplasia of the hip or Perthes' disease, for whom an operation is considered, undergo examination under anaesthetic and a hip arthrogram. This prospective study assessed whether the arthrogram modified treatment and analysed the reliability of its interpretation. All children undergoing a hip arthrogram for developmental dysplasia of the hip and Perthes' disease over a 12-month period were included. Treatment plans before and after the arthrogram were compared for each of the three children's consultants. The preoperative and arthrographic appearances were blindly reviewed to monitor reproducibility. Twenty-one patients with developmental dysplasia of the hip and 19 with Perthes' disease were included. The treatment plan was modified in 12 of the 21 (57.1%) patients with developmental dysplasia of the hip as a consequence of the arthrogram and six of the 19 patients (31.6%) with Perthes' disease. Intraobserver consultant agreement was high but interobserver agreement was only moderate. Static and dynamic arthrography helps decision-making in patients with developmental dysplasia of the hip and Perthes' disease.     

Magnetic resonance arthrography of labral disorders in hips with dysplasia and impingement

Despite the fact that classic studies on osteoarthritis of the hip have shown the periphery of the hip to be prone to degeneration, it was not until recently that an abnormal acetabular labrum has been associated with osteoarthritis. This study was designed to determine whether magnetic resonance arthrography can show differences in disorders of the labrum (tears, size, ganglion formation) expected in symptomatic patients with developmental dysplasia of the hip and anterior femoroacetabular impingement. Fourteen patients in each group were evaluated preoperatively not only clinically but also with conventional radiographs and magnetic resonance arthrographs. In both conditions, disorders of the labrum localized identically with a predilection to the anterosuperior quadrant of the acetabulum. Labral tears were observed in nine hips of each group. The labrum was enlarged in 12 hips with dysplasia but in none of the hips with impingement. Ganglion formation in the periacetabular area was seen in 10 hips with dysplasia and three hips with impingement. These findings provide evidence that the anterosuperior acetabulum represents the initial fatiguing site of the hip under both conditions. Based on these data, the size of the labrum and the presence of soft tissue ganglia seem to be good predictors for the presence of developmental dysplasia, whereas the presence of tears did not differentiate between conditions. The capability of magnetic resonance arthrography to show these differences in labral disorders suggests this method is a helpful diagnostic tool that can aid in defining the most appropriate treatment strategy.     

发育性髋关节发育不良髋臼形态变化的MRI分析

目的通过MRI定量分析,探讨发育性髋关节发育不良(DDH)患者髋臼形态的病理变化特点。方法笔者自2011-05—2015-03对53例(106髋)发育性髋关节发育不良患者进行MRI扫描检查,选取69髋为试验组,选取30例(30髋)双侧髋关节完全正常儿童为对照组,测量对照组及试验组髋关节的骨性髋臼指数(BAI)、软骨髋臼指数(CAI)、前骨性髋臼指数(ABAI)、前软骨性髋臼指数(ACAI)、后骨性髋臼指数(PBAI)、后软骨性髋臼指数(PCAI)、骨性髋臼前倾角(BAAV)、软骨性髋臼前倾角(CAAV),分析年龄与髋关节MRI测量指数的相关性、各组间MRI测量指数的差异及相关性特点。结果对照组年龄与BAI(r=-0.715)、CAI(r=-0.597)存在负相关;试验组BAI、CAI、ABAI、ACAI、BAAV、CAAV与对照组比较差异有统计学意义(P0.05),其中BAI、CAI在试验组亚组中Ⅱ度、Ⅲ度与Ⅰ度之间差异有统计学意义(P0.05),ABAI仅在试验组亚组Ⅰ度与Ⅲ度之间差异有统计学意义(P0.05),ACAI、BAAV与CAAV在试验组诸亚组之间差异无统计学意义;试验组(r=0.384)及对照组(r=0.551)的BAI与CAI之间存在正相关。结论 MRI可以有效评价髋臼形态改变;髋臼软骨相对年龄变化更为稳定,评价髋关节形态更为准确;DDH患者髋臼骨性及软骨性缺损主要位于髋臼外上缘及前缘,软骨性改变与骨性改变相关而非完全同步。     

Magnetic resonance tomography and arthrography of the hip joint

Plain film radiographs represent the imaging of choice for the initial evaluation of pathologies of the hip. However, many lesions of the joint itself and surrounding soft tissues are often not visualized by conventional radiographs. Magnetic resonance imaging (MRI) demonstrates most of these pathologies with high sensitivity and specificity. For further assessment of intra-articular lesions such as labral tears, hyaline cartilage lesions, rupture of the ligamentum teres, and loose bodies, direct MR arthrography after intra-articular administration of contrast medium may be indicated. This article summarizes the technical aspects and the most important indications for MRI and MR arthrography of the hip in correlation with typical imaging findings of the most frequent pathologies.     

Magnetic resonance arthrography

For decades, fluoroscopic arthrography was the only method available to image a joint with contrast enhancement. Advances in CT led to the natural development of CT arthrography. Development of MRI and its capability for multiplanar imaging led to direct magnetic resonance arthrography (MRA). This technique has been performed since 1987 and has surpassed CT arthrography in popularity in the United States. Indirect MRA developed subsequently to offer a less invasive alternative. This article presents an overview of direct MRA and addresses joint-specific issues regarding direct MRA. An overview of indirect MRA also is provided.     

Concordance between hip ultrasonography and hip arthrography in the assessment of developmental dysplasia of the hip.

Controversy exists regarding the possibility of predicting hip reducibility in the congenitally dislocated hip, with arthrography still regarded as the gold standard in this situation. This study aims at assessing the degree of concordance between ultrasonography and arthrography in the detection of anatomic elements obstructing hip reduction. Forty-nine hips were studied both by ultrasonography and arthrography. Three anatomic sources of obstruction to reduction were assessed in each hip: ligamentum teres hypertrophy, inverted labrum, and the presence of soft tissue in the acetabulum. For each variable, congruence between ultrasound and arthrography was measured by kappa analysis. Values > 0.40 expressed sufficient concordance, and they were detected with regard to inverted labrum and the presence of soft tissue in the acetabulum. The results of this study suggest that ultrasonography may be considered a reliable technique for the prediction of the main causes of obstruction in the congenitally dislocated hip, such as inverted labrum and soft tissue in the acetabulum.     

Seasonal variation in children with developmental dysplasia of the hip

Background

It has been postulated that developmental dysplasia of the hip (DDH) is more frequent in infants born in the winter months. It was the purpose of this study to ascertain if there was any seasonal variation in DDH at the author’s institution and compare/contrast our results with those in the literature using rigorous mathematical fitting.

Methods

All children with DDH treated at the author’s institution from 1993 to 2012 were identified. The month of birth was recorded and temporal variation was analyzed using cosinor analysis. Similar data from the literature was analyzed.

Results

There were 424 children (363 girls, 61 boys). An additional 22,936 children were added from the literature for a total of 23,360. Pearson’s Chi-square test demonstrated a non-uniform distribution in the month of birth for both our 424 children as well as the combined literature series in both the Northern and Southern hemispheres. Cosinor analysis of the 424 children demonstrated double peaks in mid-March and mid-October. For the entire 23,360 children, no seasonal variation was observed in 2,205 (9.4 %), a single winter peak in 16,425 (70.3 %), a single summer peak in 1,280 (5.5 %), and double peaks in the spring and autumn in 3,450 (14.8 %).

Conclusions

This study partly supports the hypothesis of tight clothing/cold temperature as one factor in the etiology of DDH with the tighter clothing/swaddling increasing the risk of DDH. However ~20 % of the DDH births demonstrated a non-winter peak. The single summer and double spring/autumn peaks, as well as in those series where no seasonal variation was noted, refutes the cold winter clothing hypothesis. Perhaps these different patterns in seasonal variation represent the heterogeneity of the genetic factors in DDH interacting with external factors (temperature and clothing) and internal factors (metabolic). Further study will be required to understand these different patterns in DDH seasonal variation.

Level of evidence

IV—case series.     

Magnetic resonance imaging evaluation of surgical management in developmental dysplasia of the hip in childhood.

Magnetic resonance imaging (MRI) was performed on 73 hips in 59 children aged 3 to 16 months after surgical reduction of developmental dislocation of the hip. Twenty-seven hips in 22 children had repeat MRI 6 weeks after reduction, and 20 hips in 16 patients had further MRI at least 1 year later. Only 38% of hips appeared concentrically reduced on the initial MRI scan, but this increased to 90% by 1 year later, without intervention. The authors measured coronal plane acetabular index and transverse plane anterior, posterior, and axial acetabular indices, as well as acetabular version and anteversion. Persistent difference could be shown in the coronal plane acetabular index between the dysplastic and normal sides for the cartilaginous anlage and the bony model of the acetabulum in scans performed at least 1 year after reduction. However, 40% of cartilaginous coronal plane acetabular indices fell within the "normal" range at 1 year. No other parameters could be shown to be persistently different.     

Magnetic resonance imaging in congenital dysplasia of the hip

This study was designed to determine the usefulness of magnetic resonance imaging (MRI) in managing congenital hip dysplasia and dislocation. We compared various hip parameters using bony and cartilaginous landmarks. MRI determined that the bony acetabular index (AI) accurately reflects the cartilaginous AI. Bony acetabular indices greater than 30 degrees indicated hip dysplasia, subluxation, or dislocation. MRI demonstrates qualitative information not available on plain films; however, it does not provide further quantitative data, so we do not recommend its routine use in the evaluation of congenital hip dysplasia. The true benefit of MRI may be its ability to identify a group of patients with bone dysplasia but normal cartilaginous growth potential.     

Prevalence of developmental dysplasia of the hip in children with clubfoot

Purpose

The relationship between congenital talipes equinovarus (CTEV) and developmental dysplasia of the hip (DDH) remains uncertain. The role of routine hip screening in children with CTEV is debated. A recent study has found a high incidence of DDH in patients with CTEV. The aim of our study was to determine the true prevalence of radiographic hip dysplasia and identify the need for routine hip screening in patients treated for CTEV.

Methods

From a single centre database of 165 children consisting of 260 CTEV, a prospective radiological prevalence study of 101 children was performed over a period of 3 months. A single anterior-posterior pelvic radiograph was performed at a minimum age of 5 months. The DDH was determined by a single senior investigator based on the age-adjusted acetabular index (AI) as described by Tonnis.

Results

There were no dislocations or subluxations. According to the age-adjusted AI, 16 children had ‘light’ dysplasia and one child had ‘severe’ dysplasia. The child with severe dysplasia was known to have DDH and had already undergone treatment. The 16 children with light dysplasia did not require any form of treatment.

Conclusion

Out of one hundred and one children with CTEV, only one had DDH requiring treatment. This is consistent with the majority of the literature supporting the premise that there is no true association between CTEV and DDH. We, therefore, feel that routine hip screening for children with CTEV is not supported by current evidence and cannot be recommended.     

Assessing the risk of asymptomatic dysplasia in parents of children with developmental hip dysplasia

ObjectiveThe aim of this study was to investigate whether being the parents of children with developmental hip dysplasia (DDH) is a risk factor for asymptomatic dysplasia.MethodsAsymptomatic parents of children who were diagnosed with DDH were assessed for presence of dysplasia by examining their anteroposterior pelvis radiographs at the neutral position. Eighty-six hips of 43 participants were included in the study group and 98 hips of 49 participants were included in the control group. Presence of hip dysplasia over the anteroposterior pelvis radiographs was analyzed for Wiberg's angle, acetabular index of the weight-bearing zone (the Tönnis angle), acetabular depth/width index, femoral head coverage ratio (FHCR) and femoral neck/shaft angle.ResultsThe mean acetabular depth/width ratio was 44.3% in the study group and 53.5% in the control group. And, the mean FHCR was 80% in the study group and 82% in the control group. There was a statistically significant difference between the two groups in terms of mean acetabular depth/width ratio (p < 0.05) and FHCR (p < 0.05). In addition, 21 participants in the study group and 2 in the control group had a pathological acetabular depth/width ratio. And, the number of participants with a pathological FHCR was 22 in the study group and 13 in the control group. A statistically significant difference was found between the two groups regarding the number of pathological measurements of acetabular depth/width ratio (p < 0.05) and FHCR (p < 0.05).ConclusionHaving a parent with DDH is a definitive risk factor for the development of hip dysplasia in childhood. In addition, being a parent of a child with DDH is a risk factor for asymptomatic dysplasia. These parents should be screened by roentgenogram.Level of EvidenceLevel III, Diagnostic Study.     

Magnetic resonance arthrography versus arthroscopy in the evaluation of articular hip pathology

In this study, we compared magnetic resonance arthrography results with hip arthroscopy findings to assess the diagnostic value of this imaging technique in evaluating acetabular labral tears and concurrent articular hip pathology. One hundred one consecutive patients (102 hips) with a clinical diagnosis of acetabular labral tear were assessed using magnetic resonance arthrography and had hip arthroscopy after failing to improve with nonoperative treatment. Magnetic resonance arthrography detected 71 of 93 (76%) acetabular labral tears (92 patients) with five false positive studies in five patients (4.9%). Articular cartilage findings diagnosed by magnetic resonance arthrography were confirmed by arthroscopy in 64 hips in 64 patients (62.7%). With respect to labral pathology, magnetic resonance arthrography showed a sensitivity of 71%, specificity of 44% positive predictive value of 93%, negative predictive value of 13%, and accuracy of 69%. With respect to articular cartilage pathology, magnetic resonance arthrography had a sensitivity of 47%, specificity of 89%, positive predictive value of 84%, negative predictive value of 59%, and accuracy of 67%. Although magnetic resonance arthrography is an excellent positive predictor in diagnosing acetabular labral tears and articular cartilage abnormalities, it has limited sensitivity. A negative imaging study does not exclude important intra-articular pathology that can be identified and treated arthroscopically.     

大龄儿童发育性髋关节脱位的手术治疗

目的 总结不同手术方法治疗大龄儿童发育性髋关节脱位的疗效.方法 1985年至2005年期间分别采用Salter截骨术、Pemberton截骨术和髋臼造盖成形术治疗6～15岁发育性髋关节脱位患儿56例(62髋).结果 31例(33髋)获平均8.5年(2.5～15年)随访,根据周永德疗效评定标准,优17髋、良11髋、中2髋、差3髋,总优良率为85%.Salter骨盆截骨术组优良率为87%;Pemberton截骨术组优良率为83%,1例股骨头坏死;髋臼造盖成形术组优良率为85%,1例股骨头坏死,1例严重髋关节僵硬;同时行股骨粗隆下截骨的22例(23髋)中无一例发生股骨头坏死和术后脱位.结论 正确选择术式是大龄儿童发育性髋关节脱位获得良好疗效的关键,术式的选择主要根据病理变化和年龄.股骨粗隆下截骨能有效降低头臼压力,减少股骨头坏死和再脱位发生率.     

Magnetic resonance imaging analysis of hip joint development in patients with diastrophic dysplasia

The authors used magnetic resonance imaging to evaluate the hip joint in patients with diastrophic dysplasia. T1- and T2-weighted images were obtained from 35 patients (25 female patients, 10 male patients) of different ages (1-39 years). The status of the joint and paraarticular soft tissues was evaluated. Hip joint congruity was good, although the joint was usually deformed. The thickness of the joint cartilage was diminished and signs of early osteoarthritis, including bone cysts and local edema, were common. The ligamentum teres was visible in only 24% of patients, suggesting abnormality of the ligamentous structures. Epiphyses were flattened or absent in all young patients. Of the 17 visible epiphyses, 7 showed avascular necrosis, indicated as a decrease in signal intensity in both T1- and T2-weighted images. It seems that proximal femoral epiphysis fails to bear normal weight pressure.     

Micro-CT软骨成像监测发育性髋关节发育不良大鼠髋关节软骨早期退变的应用价值

目的应用micro-CT监测发育性髋关节发育不良（DDH）大鼠髋关节软骨早期退变并建立相应影像与组织病理改变之间的联系。方法建立新生Wistar大鼠DDH动物模型（n=20）,设正常对照组（n=12）,于生后10天、4周、6周和8周获取两组髋关节标本,分别行基于造影剂Hexabrix320的micro-CT髋关节软骨成像及组织学蕃红O染色检测,计算股骨头软骨层造影剂浓聚度和石蜡切片蕃红O染色光密度值（OD）以反映软骨基质硫酸糖胺聚糖（sGAG）的含量,采用t-Test,单因素方差分析,LSD-t检验和一般线性回归对数据结果进行统计学分析。结果各时间点的模型组动物关节囊均较对照组明显增厚,伴不同程度的髋关节脱位,生后4周出现髋臼变浅,6周和8周时股骨头变扁,髋臼上方形成假臼;模型组和对照组股骨头软骨层的micro-CT造影剂浓聚度均随时间推移进行性升高（模型组：F=94.265,P〈0.01;对照组：F=108.168,P〈0.01）,但模型组造影剂浓聚度从6到8周时仍显著升高（P〈0.05）,而对照组后两时间点间的差异无统计学意义（P〉0.05）;各时间点模型组的造影剂浓聚度均明显高于对照组（10d：t=5.043;4周：t=5.899;6周：t=5.137;8周：t=9.781,所有P〈0.01）;蕃红O染色OD值与micro-CT造影剂浓聚度变化趋势相反,且二者呈显著负相关（r=-0.867,P〈0.01）。结论 micro-CT软骨成像技术能反映髋关节软骨的退变程度,可发现DDH髋关节软骨的早期退变。     

Dynamic magnetic resonance guided treatment of developmental dysplasia of the hip

This study demonstrates the feasibility and advantages of near real-time, multiplanar, dynamic magnetic resonance image-assisted treatment of patients with developmental dysplasia of the hip. Pathoanatomy and dynamic blocks to reduction are visualized with anatomic clarity not otherwise possible. Continuous imaging allows accurate assessment and maintenance of optimum positioning throughout the casting procedure. Patient charges for this new technique are less than standard methods of treatment, and the child receives no ionizing radiation.     

不同年龄组大龄发育性髋关节脱位患儿手术疗效的临床研究

[目的]探讨不同年龄组大龄发育性髋关节脱位(developmental dysplasia of the hip,DDH)患儿的手术治疗效果。[方法]2006年11月~2014年6月采用髋关节切开复位,骨盆Pemberton、Dega髋臼成形或三联截骨,股骨旋转短缩截骨结合内收肌切断等手术一期治疗大龄儿童DDH 91例(104髋),按年龄情况将患儿分为两组:低龄组(<10岁):61例(70髋),年龄6~9.8岁,平均7.9岁。高龄组(≥10岁):30例(34髋),年龄10~15岁,平均12.5岁。[结果]91例术后均获得随访,随访时间2~8年,根据Severin影像学评价标准,低龄组:Pemberton术后优良率91.43%,Dega术后优良率85.71%,骨盆三联截骨术后优良率85.71%;高龄组:Pemberton术后优良率58.33%,Dega术后优良率50.00%,骨盆三联截骨术后优良率40.00%。根据Mckay临床评价标准,低龄组:Pemberton术后优良率88.57%,Dega术后优良率85.71%,骨盆三联截骨术后优良率85.71%;高龄组:Pemberton术后优良率58.33%,Dega术后优良率41.67%,骨盆三联截骨术后优良率40.00%。[结论]本研究针对6岁以上大龄DDH患儿的手术疗效进行随访,发现大龄DDH是可以选择性的通过手术治疗的,同时通过比较两组患儿手术疗效的差异,发现低龄组的术后临床及影像学优良率均高于高龄组,提示DDH患儿需要早期手术改善头臼覆盖关系,才有可能获得较好的临床效果。     

Pemberton osteotomy for developmental dysplasia of the hip in older children

The authors reviewed the results of the Pemberton osteotomy as treatment of developmental dysplasia of the hip in 17 hips treated after 7 years of age. Twelve hips required one or more concomitant surgical procedures. The average age at the time of the osteotomy was 9.3 years, and the average follow-up was 9.4 years. Using modified McKay's clinical criteria, 14 hips were classified as excellent or good. Using Severin's radiographic classification, 13 hips met class I-II criteria. Two patients who preoperatively showed Kalamchi and MacEwen's group IV severe avascular necrosis, plus two patients whose necessary acetabular coverage was not achieved by the Pemberton osteotomy without femoral varus osteotomy, were found to meet Severin's class III-IV criteria. Pemberton osteotomy can be an effective procedure for older children in whom progressive acetabular development is not expected, although this osteotomy may have to be combined with other operative procedures.