Developmental dysplasia of the hip practice guideline: technical report. Committee on Quality Improvement, and Subcommittee on Developmental Dysplasia of the Hip

Lost in research translation: Female athletes are not male athletes, especially at the hip

Altered shape of the proximal femur (cam morphology) or acetabulum (pincer morphology) is indicative of femoroacetabular impingement, which can result in hip pain and osteoarthritis of the hip. As mechanical load during growth affects the resulting bone shape, there is strong evidence in males that cam morphology develops during skeletal growth while physes are open, rather than as an adaptation after growth plates are closed (skeletal maturity). This adaptation is particularly evident in athletes who participate at elite levels prior to skeletal maturity. The research providing this evidence, however, has primarily focused on male athletes. Despite the lack of inclusion in the research, females consistently comprise two thirds of the clinical and surgical populations with structural hip pain or pathology. Knowledge gained from male-dominated cohorts may not appropriately transfer to female athletes, especially at the hip. This perspectives article briefly reviews differences between females and males in femoral and acetabular structure, hormones, timing of puberty/maturation, hypermobility, activity level and movement control-factors which affect hip structure development and loading. Without female-focused research, the application of research findings from male athletes to female athletes may lead to ineffective or even inappropriate recommendations and treatments. Thus, there is a critical need for investment in research to promote life-long hip health for females.

Why all newborn hip screening programs have same results-a mini review

All newborns are screened for developmental dysplasia of the hip (DDH), but countries have varying screening practices. The aim of this narrative mini review is to discuss the controversies of the screening and why it seems that all screening programs are likely to have same outcome. Different screening strategies are discussed alongside with other factors influencing DDH in this review. Universal ultrasound (US) has been praised as it finds more immature hips than clinical examination, but it has not been proven to reduce the rates of late-detected DDH or surgical management. Universal US screening increases initial treatment rates, while selective US and clinical screening have similar outcomes regarding late detection rates than universal US. This can be explained by the extrinsic factor affecting the development of the hip joint after birth and thus initial screening during the early weeks cannot find these cases.  Conclusion: It seems that DDH screening strategies have strengths and limitations without notable differences in the most severe outcomes (late-detected cases requiring operative treatment). Thus, it is important to acknowledge that the used screening policy is a combination of values and available resources rather than a decision based on clear evidence.

Ultrasonography in the evaluation of various factors of developmental dysplasia of the hip in infants: Results from a retrospective study in a large hospital of northwest China

BACKGROUND

The occurrence and development of developmental dysplasia of the hip (DDH) are related to a variety of factors, which have been reported in the literature, but the literature does not mention factors related to the severity of DDH. The purpose of this study is to analyze the related factors of the occurrence and severity of DDH in combination with the Graf ultrasonic diagnostic classification.

METHODS

This study was a monocentric retrospective study describing the factors associated with DDH in a large hospital of northwest China. A total of 3046 infants (6092 hips) within 6 months after birth using the Graf method were admitted to our department between 2014 and 2018. We analyzed data of DDH. After reviewing medical charts and diagnostic examination results, we assessed whether factors such as ethnicity, gender, gestational age, birth weight, diagnosis age, maternal age, mode of delivery, fetal presentation, amniotic fluid volume and birth order, had any effect on development of hip.

RESULT

① Analysis showed that DDH mostly occurs in female and left hip joint, related to intrauterine fetal presentation, amniotic fluid volume, gestational age, mode of delivery, prenatal weight, and diagnosis age after birth, and the occurrence of DDH is also related to maternal age (All P＜0.05). Ethnicity and first born showed have no obvious correlation with DDH incidence (p = 0.718, 0.147, respectively). ② The strongest correlation was found with amniotic fluid, followed by birth weight. ③ The severity of DDH was correlated with ethnicity, births, prenatal weight, gestational age, diagnosis age and maternal age (All P＜0.05, respectively). ④ There were significant differences in treatment methods, duration and prognosis among different types of DDH.

CONCLUSIONS

The occurrence and development of DDH are related to a variety of factors. Ultrasound examination can provide an early assessment of the hip development status of infants and may play an important role in establishing an early clinical diagnosis treatment and monitoring and prognosis.

Incidence of risk factors in developmental dysplasia of the hip: a retrospective study on 18,954 cases

BACKGROUND

DDH is 1 of the most important causes of childhood disability. A diagnosis of instability can be made in the neonatal period via the Ortolani and Barlow manoeuvres. However, clinical examination, although highly specific, has poor sensitivity as compared to ultrasound. There is controversy between the necessity of universal screening for dysplasia of all newborns or selective screening reserved for those with clinical signs of instability or known risk factors of DDH.

AIM

To analyse the risk factors of congenital hip dysplasia in a consecutive case series of children referred for diagnosis and treatment of DDH.

MATERIALS AND METHODS

This was a cross-sectional study on infants consecutively examined between January 2000 and December 2019 at the Marino Ortolani Centre in Ferrara, Italy. The first 3 types on Graf's classification were considered physiological (1A, 1B, 2A+), while the last 6 pathological (2A-, 2B, 2C, 2D, 3, 4).

RESULTS

18,954 infants met the inclusion criteria and were therefore considered eligible for the study. Of these 18,954 infants, 56% (n = 10,629) were females and 44% (n = 8325) were males. According to Graf classification, 34.9% (n = 6621) were 1A, 52.7% (n = 9999) were 1B, 4.0% (n = 753) were 2A+, 2.5% (n = 478) were 2A-, 1.5% (n = 284) were 2B, 1% (n = 196) were 2C, 1.3% (n = 243) were 2D, 1% (n = 193) were 3 and 1.0% (n = 187) were 4. The most significant risk factor was the female gender (OR 5.36; 95% CI, 4.63-6.20) followed by a family history (OR 2.35; 95% CI, 2.08-2.65), then skeletal pathologies (OR 2.04; 95% CI, 1.21-3.42), oligohydramnios (OR 1.75; 95% CI, 1.44-2.13), and finally breech presentation (OR 1.42: 95% CI, 1.27-1.60).

CONCLUSIONS

Based on our data, family history, musculoskeletal disease, oligohydramnios and breech presentation are the main risk factors for DDH development, as is the female sex.

Incidence, Prevalence, Risk Factors, and Clinical Treatment for Children with Developmental Dysplasia of the Hip in Saudi Arabia. A Systematic Review

BACKGROUND

Developmental dysplasia of the hip (DDH) leads to pain, joint instability, and early degenerative joint disease. Incidence, prevalence, and management strategies of DDH have been well-documented in several countries, but not in Saudi Arabia.

OBJECTIVE

We synthesized the current evidence regarding incidence, prevalence, risk factors, and clinical treatment for children with DDH in Saudi Arabia.

METHODS

We searched 3 databases to locate studies. Studies that included children with DDH in Saudi Arabia; reported either incidence rate, prevalence, risk factors, and/or clinical practice; and were available in English or Arabic were included. We excluded reviews, case studies, or animal studies. Two independent authors reviewed potential studies and assessed study's quality.

RESULTS

Our search yielded 67 potential studies, of which 16 studies were included (total DDH sample = 3,127; age range = 2.5 to 86.4 months). Three studies reported incidence rates ranging from 3.1 to 4.9 per 1000 births, and 3 studies reported prevalence ranging from 6 to 78%. Nine studies reported that female sex, breech position, family history, and age less than 3 years were risk factors associated with DDH. Four studies reported that brace applications and closed reduction were conservative treatments, and 9 studies reported that open hip reduction, adductor tenotomy, and/or pelvic osteotomy were surgical approaches to treat DDH.

CONCLUSIONS

In Saudi Arabia, the Incidence and prevalence rates of DDH are 3.1 to 4.9 per 1,000 births, and 6-78%, respectively (differ from what has been reported in other countries), but the risk factors of DDH in Saudi Arabia appear to be similar in comparison to other countries (female, breech presentation, family history of DDH).

Developmental dysplasia of the hip and ultrasound reading by pediatric orthopedic surgeons: a pilot study

Ultrasound is an imaging modality utilized for early detection and follow-up of developmental dysplasia of the hip (DDH) in infants. Traditionally, pediatric orthopedic surgeons have relied on radiologists to perform ultrasound examinations and interpret the imaging. Today, however, many orthopedic surgeons are performing and interpreting ultrasound themselves. The purpose of this paper was to evaluate the reliability of pediatric orthopedic surgeons in interpreting ultrasound imaging of infant hips. This was a prospective observational pilot study. After reading an instructional handout about the Graf method of hip ultrasonography, eight pediatric orthopedic surgeons measured 28 hip ultrasound images to determine the alpha angle and percent femoral head coverage. On the basis of cited intraclass correlation coefficient cutoff values, interrater reliability was found to be 'good' for percent femoral head coverage and 'fair' for alpha angle. These findings are equivalent to findings of similar studies using radiologists as examiners. Pediatric orthopedic surgeons can interpret ultrasound exams for diagnosing DDH.

Costs of abduction treatment in developmental dysplasia of the hip. Analysis of 900 patients

BACKGROUND

Developmental dysplasia of the hip (DDH) is a disorder of hip development that leads to dysplasia, subluxation, or total hip dislocation. Early detection of DDH is important, and early initiation of abduction treatment is key to successful correction of the hip joint. However, mild forms of DDH, including hip instability without complete dislocation, have good spontaneous healing potential, and a watchful waiting strategy in mild DDH has been found to be safe. In this study, we aimed to evaluate the cost differences between different treatment strategies for DDH.

MATERIAL AND METHODS

Data were collected retrospectively from the medical records of all children diagnosed with diagnosis and treatment of DDH in Tampere University hospital between 1998 and 2018. In total, 948 patients were included in the study. Patients who underwent casting or operative treatment (n = 48) were excluded from the analysis. All Ortolani positive children were subjected to early abduction treatment. Children with Ortolani negative DDH were subjected to either watchful waiting or early abduction treatment, based on the clinicians' decision. The regression model estimates for the number of clinical visits with and without ultrasound examination were assessed together with cost reports from Tampere University Hospital for the calculation of savings per patient in spontaneous recovery.

RESULTS

Alpha angles at one month of age (p < 0.001) and treatment method (p < 0.001) affected the number of clinical visits and ultrasound examinations during the treatment follow-up. A low alpha angle predicted closer follow-up, and children with spontaneous recovery had lower numbers of clinical visits and ultrasound examinations than children in abduction treatment. Spontaneous recovery was found to result in approximately 375€/patient savings compared to successful abduction treatment.

CONCLUSION

With correct patient selection, a watchful waiting strategy is cost-effective in treating mild developmental dysplasia of the hip, considering the high percentage of spontaneous recovery.

[Hip dysplasia]

BACKGROUND

Hip dysplasia is one of the most common malformations in childhood and has a significant impact on the further life of those affected. A distinction must be made between congenital and the much rarer acquired dysplasia. Early diagnosis and therapy are pivotal for further development of patients.

OBJECTIVES

The paper gives an overview of current radiological possibilities of diagnosis with focus on congenital hip dysplasia supplemented by insights into therapeutic options.

MATERIALS AND METHODS

Basic and review papers were analyzed.

RESULTS

Clinical examination of the newborn has low sensitivity and specificity in the diagnosis of hip dysplasia. The introduction of Graf ultrasound screening has significantly improved the early detection of dysplastic hips. With the help of sonography, but also magnetic resonance imaging (MRI), the shape of the acetabulum and the position of the femoral head in the socket can be precisely and quickly determined, while X‑ray examinations have their place especially in the context of follow-up examinations after treatment from the age of 1 year and in the diagnosis of secondary dysplasia. Therapeutic options range from spreading treatment to open reduction with fixation in the newborn as well as conversion osteotomy in older children.

CONCLUSION

Early detection of hip dysplasia is critical to the course of treatment. The right choice of examination method and correct performance are essential for further treatment.

Acetabular Rim Disorders: Epidemiology, Etiology, Management, and Outcomes

» Anatomic disorders of the acetabular rim are a common, correctable source of hip pain in younger patients.» Some common conditions of involving abnormal acetabular rim morphology include developmental dysplasia of the hip, pincer-type femoroacetabular impingement, acetabular protrusion, and acetabular retroversion.» Treatment option for these conditions were historically limited to open osteotomy and osteoplasty procedures; however, there is increasing use of arthroscopic intervention for these patients.» Arthroscopic intervention has demonstrated short-term success in a variety of focal acetabular rim disorders; however, further research is needed to determine the long-term outcomes of these procedures and their utility in more global pathology.

Evaluation of mechanistic serum and urine biomarkers for secondary osteoarthritis associated with developmental dysplasia of the hip

Objective

Determine measurable differences for mechanistic urine and serum biomarkers in patients with developmental dysplasia of the hip (DDH) prior to, and following, secondary hip osteoarthritis (OA) when compared to controls.

Design

Urine and serum were collected from individuals with developmental dysplasia of the hip (n = 39), prior to (Pre-OA DDH, n = 32) and following diagnosis of secondary hip OA (Post-OA DDH, n = 7), age-matched Pre-OA controls (n = 35), and age-matched Post-OA controls (n = 12). Samples were analyzed for protein biomarkers with potential for differentiation of hip status through a Mann-Whitney U test with a Benjamini-Hochberg correction.

Results

Several interleukin and degradation related proteins were found to be differentially expressed when comparing DDH-related hip status prior to and following diagnosis of hip OA. In addition, MCP-1 and TIMP-1 were significantly different between younger and older patients in the control cohorts.

Conclusion

These results provide initial evidence for serum and urine protein biomarkers that define clinically relevant stages of symptomatic DDH and its progression to secondary hip osteoarthritis categorized by known mechanisms of disease.

Level of evidence

III.

Analysis of the results of hip ultrasonography in 48 666 infants and efficacy studies of conservative treatment

PURPOSE

This study aimed to investigate the detection rate of developmental dysplasia of the hip (DDH) by ultrasound. To obtain the distribution characteristics of the different types (I-IV) and the role of ultrasound in the evaluation of infants with DDH (type IIc and above) receiving conservative treatment.

METHODS

A retrospective analysis was performed. The chi-square test was used for comparisons between count-data groups. Two-sided tests were used for all analyses. The results of ultrasound follow-up after conservative treatment are described.

RESULTS

Among the 48 666 infants examined, the detection rates were as follows: type I, 95.42%; IIa, 3.18%; IIb, 0.91%; IIc, 0.22%; D, 0.01%; III, 0.14%; and IV, 0.12%. There were 4456 hips with IIa and above, more left (54.65%) than right (45.35%) hips, and more females (82.60%) than males (17.40%). The detection rate of type IIa and above was 4.58%, and that of type IIb and above was 1.40%. After the treatment, the α value increased, and β value decreased. The cure rate of the less-than-42-days group was higher than that of the other groups.

CONCLUSION

The ultrasound detection rate of DDH is high. DDH was more likely to occur on the left side and in females. It is recommended that the infants should be treated within 42 days.

Radiographic markers of hip dysplasia in young adults: predictive effect of factors in early life

ABSTRAC

BACKGROUND AND OBJECTIVES: Acetabular dysplasia in young adults occurs, despite screening for developmental hip dysplasia (DDH) in the neonatal period. We aimed to examine how early life factors predict radiographic measurements of acetabular dysplasia at 18-19 years of age.

METHODS

From a previous randomized trial (n = 12,014; 1988-90) evaluating the role of hip ultrasound in newborn screening of DDH, 4469 participants (2193 males) were invited to a follow-up 18 years later (2007-09), of which 2370 (53% attendance; 932 males) met. We examined associations between early life factors and four radiographic measurements for acetabular dysplasia at skeletal maturity. Hierarchical regressions, with addition of variables observed/measured consecutively in time, were analyzed using mixed effects models considering hip as the unit in the analyses. The study is approved by the Regional Ethics Committee.

RESULTS

In total, 2340 participants (921 boys), mean age 18.7 years, (SD 0.6) had hip radiographs performed at follow-up and were included. Early life factors significantly predicting radiographic acetabular dysplasia at age 18-19-years included female gender, breech, low acetabular inclination (alpha) angle and sonographic instability, abduction treatment, as well as the velocity of growth during childhood. A positive family history of DDH was not associated with acetabular dysplasia at skeletal maturity.

CONCLUSION

The acetabular inclination (alpha) angle as measured on ultrasound at birth turned out to be a significant predictor of dysplasia at 18-19 years of age. The discordant role of a positive family history in early versus adult hip dysplasia is intriguing, warranting further studies on the genetic mechanisms of DDH.

Prediction of Late Dysplasia Based on Ultrasound and Plain X-Ray at 6 Months

BACKGROUND

Developmental dysplasia of the hip represents a spectrum of deformity. Residual dysplasia at 2 years of age is associated with an increased risk for osteoarthritis and functional limitations. We compared the prognostic value of 6-month imaging modalities and aimed to identify optimal diagnostic metrics for the prediction of residual dysplasia.

METHODS

After IRB approval, patients who underwent Pavlik treatment between 2009 and 2018 with 2-year follow-up were identified. Sonographs [ultrasound (US)] and radiographs (x-ray) were obtained at 6-month and 2-year-old visits. Dysplasia at 2 years was defined as an acetabular index (AI) >24 degrees. Receiver operating characteristic curves were constructed to quantitatively compare the prognostic ability of US and x-ray-based measures at 6 months. Youden's index [(YI) (values range from 0 (poor test) to 1 (perfect test)] was used to evaluate existing cutoffs at 6 months of age (normal measurements: alpha angle (AA) ≥60 degrees, femoral head coverage (FHC) ≥50%, and AI <30 degrees) relative to newly proposed limits.

RESULTS

Fifty-nine patients were included, of which 28.8% of patients (95% CI: 17.3 to 40.4%) had acetabular dysplasia at 2 years. After adjusting for sex, AA [Area under the Curve (AUC): 80] and AI (AUC: 79) at 6 months of age were better tests than FHC (AUC: 0.77). Current diagnostic cutoffs for AA (YI: 0.08), AI (YI: 0.0), and FHC (YI: 0.06) at 6 months had poor ability to predict dysplasia at 2 years. A composite test of all measures based on proposed cutoffs (AA ≥73 degrees, FHC > 62% and AI ≤24 degrees) was a better predictor of dysplasia at 2 years (Youden's index (YI): 0.63) than any single metric.

CONCLUSIONS

The rate of residual dysplasia remains concerning. The 6-month x-ray and US both play a role in the ongoing management of the developmental dysplasia of the hip. The prediction of dysplasia is maximized when all metrics are considered collectively. Existing parameters were not accurate; We recommend the following cutoffs: AA ≥73 degrees, FHC > 62%, and AI ≤24 degrees. These cutoffs must be validated.

LEVEL OF EVIDENCE

Prognostic Level II.

Radiographic Follow-up After Normal Ultrasound Screening of the Hip in Breech Infants

BACKGROUND

Breech presentation is one of the most important risk factors for developmental dysplasia of the hip, and all breech infants should be screened. The necessity of further follow-up of developmental dysplasia of the hip after normal clinical and sonographic screening is a controversial subject. The purpose of this study to identify the incidence of delayed dysplasia in breech infants after normal ultrasound screening and the necessity of further clinical and radiologic follow-up in these patients.

METHODS

We included the 292 breech babies (128 boys and 164 girls) who showed normal hip ultrasound screening results. To determine the incidence of delayed radiographic dysplasia, anteroposterior hip radiographs were taken between 12 and 24 months of age to measure the acetabular index (AI).

RESULTS

The mean AI values were 22.8±3.4 in boys and 24.9±3.1 in girls. Applying the Tönnis criteria, 29 patients (9.9%) were considered to have delayed radiographic dysplasia (16 boys and 13 girls). No significant difference was found in any demographic variables between babies with and without delayed radiographic dysplasia. None of these 29 infants underwent any treatment for radiographic dysplasia. Applying Kuong's criteria to 292 infants, only 2 patients (0.7%) demonstrated radiographic dysplasia on the hip anteroposterior radiographs taken at 14 months.

CONCLUSIONS

The incidence of radiographic dysplasia significantly varied depending on which criteria were applied. In order to find out more accurate incidence rates of delayed radiographic dysplasia, large-scale studies of the normative AI data for Korean infants are required.

LEVEL OF EVIDENCE

Prognostic Level III.

Clinical examination and patients' history are not suitable for neonatal hip screening

Purpose

To assess the percentage of missed developmental dysplasia of the hip, which escape the German criteria for newborn hip high-risk screening, we analyzed our data gained from the general neonatal sonographic hip screening performed at our department. The aim of the study was to determine the number of potentially belatedly treated developmental dysplasia of the hip.

Methods

The data from 1145 standardized newborn hip ultrasound examinations according to the Graf technique were analyzed retrospectively comparing findings for general neonatal sonographic hip screening and high-risk screening subgroups.

Results

We diagnosed developmental dysplasia of the hip in 18 of the 1145 newborns via ultrasound. A total of 10 out of 18 developmental dysplasia of the hip would have been missed by high-risk screening, which corresponds to a proportion of 55.6% false-negative results. The sensitivity of high-risk screening was only 44.4% and specificity, 78.3%. The positive predictive value was 3.2%. Family history as a screening criterion yielded false-negative results in 77.8% and false-positive results in 16.8%. In all, 83.3% of the children who were born with developmental dysplasia of the hip but not from breech position as a risk factor were false negative. The clinical examination was false negative in 88.9% and false positive in 0.6%.

Conclusion

High-risk screening detected less than every second developmental dysplasia of the hip, rendering the first month as the most effective treatment window unavailable for inapparent dysplastic hips, potentially resulting in the need for more invasive treatment. Due to the high sensitivity of ultrasound in the detection of developmental dysplasia of the hip, we recommend to replace the current German high-risk screening guidelines with a general newborn screening for all neonates using Graf ultrasound in the first week of life.

Level of evidence

Level II.

Ultrasound techniques for the detection of developmental dysplasia of the hip: a systematic review and meta-analysis

BACKGROUND

Developmental dysplasia of the hip (DDH) encompasses a broad spectrum of hip pathologies, including femoral or acetabular dysplasia, hip instability, or both. According to the medical literature, ultrasonography is the most reliable diagnostic method for DDH. Several techniques for the assessment of hips in newborns and infants, using ultrasonography, have been described.

OBJECTIVE

To compare the accuracy of the Graf technique and other diagnostic techniques for DDH.

DESIGN AND SETTING

A systematic review of studies that analyzed ultrasound techniques for the diagnosis of DDH within an evidence-based health program of a federal university in São Paulo (SP), Brazil.

METHODS

A systematic search of relevant literature was conducted in the PubMed, EMBASE, Cochrane Library, CINAHL, and LILACS databases for articles published up to May 5, 2020, relating to studies evaluating the diagnostic accuracy of different ultrasound techniques for diagnosing DDH. The QUADAS 2 tool was used for methodological quality evaluation.

RESULTS

All hips were analyzed using the Graf method as a reference standard. The Morin technique had the highest rate of sensitivity, at 81.12-89.47%. The Suzuki and Stress tests showed 100% specificity. The Harcke technique showed a sensibility of 18.21% and specificity of 99.32%.

CONCLUSION

All the techniques demonstrated at least one rate (sensibility and specificity) lower than 90.00% when compared to the Graf method. The Morin technique, as evaluated in this systematic review, is recommended after the Graf method because it has the highest sensitivity, especially with the three-pattern classification of 89.47%.

REGISTRATION NUMBER

Identifier: CRD42020189686 at the International Prospective Register of Systematic Reviews (identifier: CRD42020189686).

Variability in Australian screening guidelines for developmental dysplasia of the hip

AIM

To assess the variability in Australian screening guidelines for developmental dysplasia of the hip (DDH).

METHODS

Ovid MEDLINE®, EMBASE, EMB Reviews-Cochrane, CINAHL, TRIP and grey literature were searched to identify screening guidelines for DDH. Key data items related to recommendations for timing and method of screening were extracted and summarised in a table format for qualitative analysis.

RESULTS

Seventeen guidelines met inclusion criteria, comprising nine Australian DDH screening guidelines and eight Child Health Books. The guidelines showed variation in recommendations for the examiner, specific screening methods used for high-risk groups, timing of examinations and recommendations for referral.

CONCLUSIONS

Variability exists within Australian DDH screening guidelines. Lack of knowledge regarding local screening guidelines may contribute to the current trend of increased incidence of late diagnosed DDH in Australia, reported in New South Wales, South Australia, and Western Australia. An evidence-based and consistent approach to DDH screening is necessary to minimise late detected cases.

Prevalence of Developmental Dysplasia of the Hip in a Maternity Hospital in São Paulo, Brazil

Objective  To evaluate the prevalence of developmental dysplasia of the hip (DDH), that is, hips classified as Graf type-IIc or higher, among a sample of the population of newborns aged from 0 to 3 days of life, and to correlate the findings with the main risk factors described in the literature. Methods  An observational, cross-sectional, prospective study on a sample of newborns at a Maternity Hospital School in the city of São Paulo, Brazil, to assess the prevalence of DDH diagnosed by the Graf method and verify its correlation with the risk factors. Results  A total of 678 newborns underwent hip ultrasound (1,356 hips). The prevalence of DDH was of 5.46%. The logistic regression analysis showed odds ratios (ORs) with statistical significance for the following parameters: white ethnicity (OR = 2.561; 95% confidence interval [95%CI]: 1.07 to 6.11); multiparity (OR = 3.50; 95%CI: 1.62 to 7.38), female gender (OR = 4.95; 95%CI: 1.86 to 13.13); and breech presentation (OR = 2.03; 95%CI: 1,01 to 4.11). Conclusion  The prevalence of DDH in the sample was of 5.45% using ultrasound as a diagnostic method. This result is different from that of studies that assessed prevalence exclusively through physical examination (Ortolani maneuver). The main risk factors associated with a higher risk of developing DDH were newborns of the female gender, with breech presentation, firstborns, and of white ethnicity.

Developmental dysplasia of the hip: Beyond the screening. Physical exam is our pending subject

INTRODUCTION

Developmental dysplasia of the hip is a common cause of disability among children. Early detection leads to better prognosis. There are some risk factors that increase the possibility of developing a dysplasia. But not every child with developmental dysplasia has them. This means that physical examination is still very useful to detect them. However, based on clinical findings, the amount of requested ultrasound seems higher than it would be necessary.

METHODS

Retrospective cohort study of infants born in a single tertiary care centre. Babies in which hip ultrasound was performed were included. During the period of study, patients with diagnosis of developmental hip dysplasia were also included, as well as the amount of ultrasounds requested during this period, and their efficiency.

RESULTS

Out of the 456 newborns included, 530 hip ultrasounds were performed. Just 3 of the total 12 dysplasias had risk factors. The others were diagnosed through clinical examination.

CONCLUSIONS

Screening protocols are useful to detect hip dysplasia but clinical examination is very important to detect those cases without risk factors. However, the number of tests is higher than expected according to the diagnosed dysplasias.

Automatically Delineating Key Anatomy in 3-D Ultrasound Volumes for Hip Dysplasia Screening

Developmental dysplasia of the hip (DDH) metrics based on 3-D ultrasound have proven more reliable than those based on 2-D images, but to date have been based mainly on hand-engineered features. Here, we test the performance of 3-D convolutional neural networks for automatically segmenting and delineating the key anatomical structures used to define DDH metrics: the pelvis bone surface and the femoral head. Our models are trained and tested on a data set of 136 volumes from 34 participants. For the pelvis, a 3D-U-Net achieves a Dice score of 85%, outperforming the confidence-weighted structured phase symmetry algorithm (Dice score = 19%). For the femoral head, the 3D-U-Net had centre and radius errors of 1.42 and 0.46 mm, respectively, outperforming the random forest classifier (3.90 and 2.01 mm). The improved segmentation may improve DDH measurement accuracy and reliability, which could reduce misdiagnosis.

Prenatal Screening for Developmental Displacement of the Hip: The BUDDHA (Pre-Birth Ultrasound for Developmental Displacement of the Hip Assessment) Study

Background: developmental dysplasia of the hip has an incidence of 3–5 out of 1000 children. Currently, only postnatal screening is available. Objective: to test the feasibility of a method based on Graf technique application at antenatal ultrasound in assessing the normal development of the hip in unselected term fetuses. Methods: a prospective cohort study in a single university tertiary hospital from January 2017 to January 2020. Single uncomplicated term pregnancies (37–40 weeks) attending our center for routine ultrasound were consecutively recruited for the purpose of the study. A 3D volume acquisition was launched on the coxofemoral joint of the fetus by a single expert operator, and offline analysis was then performed in the multiplanar mode by two operators (blinded to each other analysis) in order to measure the alpha and beta angles according to our modified Graf technique. Intra- and inter-observer variations were calculated. Reference charts for normal values of both angles were produced. Postnatal ultrasound was then performed to measure the Graf angles in newborns, confirming a normal development of the hip. Results: in the study period, 433 uncomplicated term pregnancies underwent 3D ultrasound for the assessment of the fetal hip. One case was subsequently excluded because of confirmed postnatal diagnosis of developmental dysplasia of the hip. The measurement of our modified Graf angles was feasible at prenatal ultrasound with a good reproducibility. The inter-rater and intra-rater reliability of both angles was substantial. Reference charts for normal values of both angles were produced. Conclusions: the evaluation of the coxofemoral joint in fetuses at term of gestation has never been attempted before. The Graf technique application, currently employed at postnatal ultrasound, may also be adapted to prenatal ultrasound with a substantial reproducibility. However, there was no evidence of a linear relationship between prenatal and postnatal alpha angles and beta angles. Further research is needed to establish if developmental dysplasia of the hip could be diagnosed antenatally.

Effectiveness of different types of ultrasonography screening for developmental dysplasia of the hip: A meta-analysis

BACKGROUND

Infant hip screening for early detection of developmental dysplasia of the hip (DDH) is essential as early detection can enable less invasive treatments and achieve better long-term results. A previous meta-analysis assessed about 10,000 infants per group, which is insufficient for evaluating the effect of different infant hip screening strategies on early detection and treatment of DDH. Therefore, we conducted a systematic review and meta-analysis using both randomized controlled trials and cohort studies to determine the effects of universal hip ultrasonography screening (UHUS) and selective hip ultrasonography screening (SHUS) on the incidence of late-diagnosed DDH.

METHODS

A literature search of PubMed, EMBASE, and Cochrane databases was performed. The summary odds ratio (OR) with 95% confidence interval (CI) was calculated using fixed-effects models.

RESULTS

Meta-analysis of five studies that met the eligibility criteria revealed a significant difference in late-diagnosed DDH (OR 0.44, 95% CI 0.23-0.83) between infants screened using UHUS (n = 29,070) and those screened using SHUS (n = 30,442) in a fixed-effects model without heterogeneity among studies. In the subgroup analysis, meta-analysis of the randomized controlled trials showed no significant difference in late-diagnosed DDH (OR 0.52, 95% CI 0.20-1.39) between infants screened using UHUS (n = 11,453) and those screened using SHUS (n = 12,077) in a fixed-effects model with low heterogeneity among studies (I = 0.9%). However, meta-analysis of the cohort studies showed a significant difference in late-diagnosed DDH (OR 0.38, 95% CI 0.17-0.89) between infants screened using UHUS (n = 17,617) and those screened using SHUS (n = 18,345) in a fixed-effects model with low heterogeneity among studies. Sensitivity analysis revealed that the impact of each study on the summary results was not significant. There was no publication bias in our meta-analysis.

CONCLUSIONS

Our meta-analysis suggests that a statistically significant decrease in the incidence of late-diagnosed DDH is possible when UHUS is adopted compared with SHUS. Our study provides information about the effects of different infant hip screening strategies on the incidence of late-diagnosed DDH, which can help decide upon which strategy to apply.

[Develomental dysplasia of the hip: beyond the screening. Physical exam is our pending subject]

INTRODUCTION

Developmental dysplasia of the hip is a common cause of disability among children. Early detection leads to better prognosis. There are some risk factors that increase the possibility of developing a dysplasia. But not every child with developmental dysplasia has them. This means that physical examination is still very useful to detect them. However, based on clinical findings, the amount of requested ultrasound seems higher than it would be necessary.

METHODS

Retrospective cohort study of infants born in a single tertiary care centre. Babies in which hip ultrasound was performed were included. During the period of study, patients with diagnosis of developmental hip dysplasia were also included, as well as the amount of ultrasounds requested during this period, and their efficiency.

RESULTS

Out of the 456 new-borns included, 530 hip ultrasounds were performed. Just 3 of the total 12 dysplasias had risk factors. The others were diagnosed through clinical examination.

CONCLUSIONS

Screening protocols are useful to detect hip dysplasia but clinical examination is very important to detect those cases without risk factors. However, the number of tests is higher than expected according to the diagnosed dysplasias.

Orthopedic and ultrasound assessment of hip stability of newborns referred by pediatricians with suspected Developmental Dysplasia

OBJECTIVE

to evaluate newborns with suspected hip instability, referred by pediatricians to a tertiary orthopedic service.

METHODS

newborns from a public university maternity hospital, with suspected instability or risk factors for hip dysplasia, were referred to the Department of Orthopedics and Anesthesiology, Ribeirão Preto/SP, where we evaluated them clinically and through ultrasound examinations of the hips. Once we found dysplasia, we initiated treatment, and in cases in which there was only hip immaturity and normal clinical examination, we performed clinical and ultrasound observation and review at two or three months of age.

RESULTS

we examined 448 newborns, with female predominance and average age at first evaluation of 27 days. The main cause of referral was pelvic presentation at delivery. In 8% there was a positive Ortolani sign and in 12.5%,. At orthopedic examination, 405 (90.5%) patients were normal, 8.5% had hip click and 1.1% had positive Ortolani test. At ultrasound, 368 (89.5%) had immaturity, 26 (6.3%) had moderate dysplasia and in 17 (4.1%) patients the hips were frankly dysplastic. All cases with positive Ortolani sign showed dysplasia at ultrasound.

CONCLUSION

there was an excess diagnosis of hip instability in the pediatrician evaluation, which, however, allowed the patient a second assessment, in a more specialized environment and with more technological resources.

Subchondral bone deterioration in femoral heads in patients with osteoarthritis secondary to hip dysplasia: A case-control study

Objectives

Residual hip dysplasia is the most common underlying condition leading to secondary osteoarthritis (OA) of the hip. Subchondral bone alterations in OA secondary to hip dysplasia (HD-OA) are poorly investigated. The aim of the present study was to analyse the microarchitecture, bone remodelling and pathological alterations of subchondral bone in femoral heads from patients with HD-OA.

Methods

Subchondral bone specimens were extracted from both weight-bearing and non–weight-bearing regions of femoral heads from 20 patients with HD-OA and 20 patients with osteoporotic femoral neck fracture, during hip replacement surgery. Micro-CT and histological examination were performed to assess the microarchitecture and histopathological changes.

Results

The weight-bearing subchondral bone showed significantly more sclerotic microarchitecture and higher bone remodelling level in HD-OA as compared with osteoporosis. In the non–weight-bearing region, the two diseases shared similar microarchitectural characteristics, but higher bone remodelling level was detected in HD-OA. Distinct regional differences were observed in HD-OA, whereas the two regions exhibited similar characteristics in osteoporosis. In addition, HD-OA displayed more serious pathological alterations, including subchondral bone cyst, metaplastic cartilaginous tissue, bone marrow oedema and fibrous tissue, especially in the weight-bearing region.

Conclusions

Osteoarthritic deteriorations of subchondral bone induced by hip dysplasia spread throughout the whole joint, but exhibit region-dependent variations, with the weight-bearing region more seriously affected. Biomechanical stress might exert a pivotal impact on subchondral bone homeostasis in hip dysplasia.

The translational potential of this article

The histomorphometric findings in the project indicate an early intervention for the development of hip dysplasia in clinic.

Transgluteal ultrasonography in spica cast in postreduction assessment of developmental dysplasia of the hip

PURPOSE

The position of the femoral head in spica cast after the reduction of developmental dysplasia of the hip (DDH) should be examined and followed up closely and regularly. The study aimed to use the transgluteal ultrasonography approach for this purpose and compare its accuracy with the results of CT scan, which is the most commonly used modality.

METHODS

Twenty-three patients with an average age of 20-21 months were examined for 1 year after the reduction of DDH, both closed and open. Ultrasonography and CT scan were performed on the patients on the same day, and the results were interpreted by different radiologists. Transgluteal ultrasonography in spica cast was performed while the legs were abducted, internally rotated, and flexed. A blanket was placed under the patient to elevate the cast.

RESULTS

Thirty cases of proper reduction (81%) and 7 cases of dislocated hip (19%) were reported in transgluteal ultrasonography, and 29 cases of proper reduction (78%) and 8 cases of dislocated hip (22%) were reported in the CT scan. The rate of agreement between the results of ultrasonography and CT scan was 91%.

CONCLUSION

Transgluteal ultrasonography can be used as an excellent modality to examine the position of the femoral head in relation to the posterior rim of the acetabulum in spica cast. The position of the femoral head can be viewed properly needless of perineal opening in the cast. Thus, transgluteal ultrasonography can replace the CT scan to assess the position of the femoral head. Sonography does not expose patients to radiation and does not require sedation.

DNA hypermethylation of GDF5 in developmental dysplasia of the hip (DDH)

INTRODUCTION & OBJECTIVE

Developmental Dysplasia of the Hip (DDH) is one of the most common congenital skeletal anomalies. Body of evidence suggests that genetic variations in GDF5 are associated with susceptibility to DDH. DDH is a multifactorial disease and its etiology has not been entirely determined. Epigenetic changes such as DNA methylation could be linked to DDH. In this scheme, we hypothesized that changes in GDF5 DNA methylation could predispose a susceptible individual to DDH.

METHODS

This study consisted of 45 DDH patients and 45 controls with healthy femoral neck cartilage, who underwent hemi-, or total arthroplasty for the femoral neck fracture. A cartilage sample of 1 cm in diameter and 1 mm in the thickness was obtained for DNA extraction. DNA was extracted and DNA methylation of GDF5 was evaluated by metabisulfite method.

RESULTS

Methylation analysis showed that the promoter of GDF5 in cartilage samples from DDH patients was hypermethylated in comparison to healthy controls (p = .001).

CONCLUSION

Our study showed that the methylation status of the GDF5 in patients with DDH is dysregulated. This dysregulation indicates that adjustment in the methylation might modify the expression of this gene. Since this gene plays an essential role in cartilage and bone development, thus reducing its expression can contribute to the pathogenesis of DDH. Further studies are needed to elucidate the role of GDF5 in this disease.

Desiderata for sharable computable biomedical knowledge for learning health systems

In this commentary, we work out the specific desired functions required for sharing knowledge objects (based on statistical models) presumably to be used for clinical decision support derived from a learning health system, and, in so doing, discuss the implications for novel knowledge architectures. We will demonstrate how decision models, implemented as influence diagrams, satisfy the desiderata. The desiderata include locally validate discrimination, locally validate calibration, locally recalculate thresholds by incorporating local preferences, provide explanation, enable monitoring, enable debiasing, account for generalizability, account for semantic uncertainty, shall be findable, and others as necessary and proper. We demonstrate how formal decision models, especially when implemented as influence diagrams based on Bayesian networks, support both the knowledge artifact itself (the "primary decision") and the "meta-decision" of whether to deploy the knowledge artifact. We close with a research and development agenda to put this framework into place.

The positive predictive value of asymmetrical skin creases in the diagnosis of pathological developmental dysplasia of the hip

Aims

The aim of this study was to identify the association between asymmetrical skin creases of the thigh, buttock or inguinal region and pathological developmental dysplasia of the hip (DDH).

Patients and Methods

Between 1 January 1996 and 31 December 2016, all patients referred to our unit from primary or secondary care with risk factors for DDH were assessed in a "one stop" clinic. All had clinical and sonographic assessment by the senior author (RWP) with the results being recorded prospectively. The inclusion criteria for this study were babies and children referred with asymmetrical skin creases. Those with a neurological cause of DDH were excluded. The positive predictive value (PPV) for pathological DDH was calculated.

Results

A total of 105 patients met the inclusion criteria. There were 71 girls and 34 boys. Only two were found to have pathological DDH. Both also had unilateral limited abduction of the hip in flexion and a positive Galeazzi sign with apparent leg-length discrepancy. Thus, if the specialist examination of a patient with asymmetrical skin creases was normal, the PPV for DDH was 0%.

Conclusion

Isolated asymmetrical skin creases are an unreliable clinical sign in the diagnosis of pathological DDH. Greater emphasis should be placed on the presence of additional clinical signs to guide radiological screening in babies and children. Cite this article: Bone Joint J 2018;100-B:675-9.

Development of unstable hips after treatment with the Tübingen splint: mid-term follow-up of 83 hip joints

INTRODUCTION

Early diagnosis and treatment of hip dysplasia are widely accepted as major factors for beneficial outcome. However, modalities for reduction and retention as well as for imaging are currently under clinical investigation. Local and general risk factors, e.g., breech presentation and the family's desire to avoid in-hospital treatment are major concerns in the decision-making process and consultation. For treatment of unstable hips in newborns the treatment with the Tübingen splint has proven good results in recent studies. However, mid- and long-term outcome studies are missing. We report on clinical results and X-ray parameter of initially unstable hips after treatment with the Tübingen splint at two time points: 12-24 and 24-48 months of age.

MATERIALS AND METHODS

Included were newborns with 83 unstable hips (type D, III, IV according to Graf) which were successfully treated with the Tübingen splint-used as reduction splint 24 h per day/7 days per week-until type I hips were documented by ultrasound examination. Measurments are based on routine pelvic X-ray control at the age of 12-24 and 24-48 months. The acetabular angle was determined and according to the Tönnis-Classification evaluated into: normal findings (< 1 s), slightly dysplastic findings (1-2 s) and severely dysplastic findings (> 2 s). Children with secondary hip dysplasia were not included in this series.

RESULTS

In 2nd year of life, 45 hips (54.2%; initial hip type D: 47.4%, III: 63.2%, IV: 42.9%) of the formerly unstable hips show normal X-ray findings. Although final ultrasound showed normal findings, at this time point 28 hips (33.7%; initial hip type D: 34.2%, III: 31.6%, IV: 42.9%) were slightly dysplastic and 10 (12.0%%; initial hip type D: 18.4%, III: 5.3%, IV: 14.3%) still severely dysplastic. At the age of 24-48 months, the percentage of radiologic normal hips had increased to 61 hips (73.5%; initial hip type D: 68.4%, III: 81.6%, IV: 57.1%), the number of slightly (19 hips) and severely dysplastic (3 hips) hips had decreased 22.9% (initial hip type D: 28.9%, III: 15.8%, IV: 28.6%) respectively 3.6% (initial hip type D: 2.6%, III: 2.6%, IV: 14.3%). At this time no operative intervention was neccessary.

CONCLUSIONS

Our mid-term data show on the one hand a good development of unstable hips after successful treatment with the Tübingen splint. On the other hand despite successful therapy and normal ultrasound findings at the end of treatment further imaging by X-ray are mandatory to close follow-up and to detect those which might need surgical correction of residual dysplasia.

Blood Transfusion Incidence, Risk Factors, and Associated Complications in Surgical Treatment of Hip Dysplasia

BACKGROUND

Perioperative bleeding requiring blood transfusion is a known complication of hip dysplasia (HD) surgery. Here we examine rates of, risk factors for, and postoperative complications associated with transfusion during HD surgery.

METHODS

The National Surgical Quality Improvement Program (NSQIP) Pediatric database was queried for patients treated by an orthopaedist from 2012 to 2013. HD cases were categorized by Current Procedural Terminology codes into femoral osteotomies, acetabular osteotomies, combined femoral/acetabular osteotomies, and open reductions. Patients were grouped by comorbidities: neuromuscular (NM) disease (eg, cerebral palsy) group, non-NM with other comorbidity (Other) group, and no known comorbidity (NL) group. Patients were stratified by weight-normalized transfusion volume. Multivariate regression analysis of transfusion association with procedures, demographics, comorbidities, preoperative laboratory values, and 30-day complications was performed.

RESULTS

A total of 1184 HD cases were included. Transfusion rates for the NL, Other, and NM groups, respectively, were 44/451 (9.8%), 61/216 (28.2%), and 161/517 (31.1%). Transfusion volumes (mean±SD) for the NL, Other, and NM groups, respectively, were 8.4±5.4, 13.9±8.8, and 15.5±10.0 mL/kg (P<0.001). Combined osteotomies had the highest transfusion rates in the NM and Other groups (35.7% and 45.8%, respectively), whereas acetabular osteotomies had the highest rate in the NL group (15.8%). Open reductions had the lowest transfusion rate (all groups). Longer operations were independently associated with transfusion (all groups, per hour increase, OR>1.5, P<0.001). Independent patient risk factors included preoperative hematocrit <31% (NM group, OR=18.42, P=0.013), female sex (NL group, OR=3.55, P=0.008), developmental delay (NM group, OR=2.37, P=0.004), pulmonary comorbidity (NM group, OR=1.73, P=0.032), and older age (NL group, per year increase: OR=1.29, P<0.001). In all groups, transfusion was associated with longer hospitalization (P<0.001). We observed a volume-dependent increase in overall complication rate within the Other group for transfusion volumes >15 mL/kg (25.0% vs. 5.4% for <15 mL/kg, P=0.048).

CONCLUSIONS

We identified several risk factors for transfusion in HD surgery. The incidence of transfusion in HD surgery and its association with adverse outcomes warrants development of appropriate patient management guidelines.

LEVEL OF EVIDENCE

Level III-prognostic.

Introducing universal ultrasound screening for developmental dysplasia of the hip doubled the treatment rate

AIM

There is no evidence on the effect of universal ultrasound screening on developmental dysplasia of the hip. We examined the impact of adding an ultrasound examination to a one examiner clinical screening strategy on treatment, follow-up rates and the number of cases detected late in a low-prevalence population.

METHODS

All eligible babies born at Kongsberg Hospital, Norway, from 1998 to 2006 (n = 4245) underwent both clinical and ultrasound hip examinations within three days of life. Indications for immediate treatment were positive Barlow or Ortolani manoeuvres and, or, sonographic dysplasia. Sonographic immature hips were followed until normalisation. Treatment rates and rates from the 1989 to 1997 prestudy period (n = 3594), including late diagnoses, were collected from hospital records.

RESULTS

Treatment was initiated in 90 (2.1%) infants (74 girls), 63 (70%) from birth, compared to 33 (0.9%) during the prestudy period. The follow-up rate did not change (11%). There were two (0.5/1000) and four (1.0/1000) cases detected late, respectively. No one underwent surgery during the first year of life and no avascular necrosis was seen.

CONCLUSION

Adding universal ultrasound to clinical screening performed by the same, experienced paediatrician doubled the treatment rate, without influencing the already low numbers of late cases.

Screening in Developmental Dysplasia of the Hip (DDH)

Screening for Developmental Dysplasia of the Hip (DDH) is a controversial subject. Screening may be by universal neonatal clinical examination (Ortolani or Barlow manoeuvres) with the addition of sonographic imaging of the hip (selective 'at risk' hips or universal screening in the neonate). In the UK, the NIPE guidelines recommend universal neonatal clinical assessment of the hip joints, a General Practitioner 6-8 week clinical 'hip check' and assessment clinically with sonographic imaging at 4-6 weeks for certain 'at risk' hips for pathological DDH. The effectiveness and difficulties arising from the UK current screening policy (clinical and sonographic) are highlighted. The purpose of the review was to assess the risk factors and efficacy of diagnostic methods in DDH, based on longitudinal cohort studies of 10 years or more.

CONCLUSION

Hip screening in DDH does not meet most of the World Health Organisation's criteria for an effective screening programme and should only be considered as surveillance due to its low sensitivity and positive predictive value (PPV). There is a significant risk of over diagnosis and over treatment. There is no International consensus on screening in DDH. Pathological DDH is mainly a female condition and 'at risk'/General Practitioner screening identifies few pathological cases in male subjects. The General Practitioner 6-8 week 'hip check' has a very low PPV for pathological DDH and is of doubtful value in screening and diagnosis. Unilateral limitation of hip abduction is a time dependent and useful clinical sign in the diagnosis of pathological DDH. The majority of the previously considered 'at risk' factors are not true risk factors with little or no association with pathological DDH.

Relative Risk and Incidence for Developmental Dysplasia of the Hip

OBJECTIVE

To determine the incidence and associated risk factors of developmental dysplasia of the hip (DDH) in a modern population without universal screening.

STUDY DESIGN

Children with DDH were identified from the Manitoba Centre for Health Policy's Data Repository by the use of International Classification of Diseases diagnosis codes as well as physician billing tariffs for surgical procedures for DDH for all children born between 1995 and 2012. To identify the outpatient-treated patients, ultrasound scans and radiographic imaging for DDH were reviewed for 2004-2012. Overall incidence was calculated on the basis of birth rate for the province per year. Relative risks of sex, first born, breech position, clubfoot deformity, multiple gestations, as well as regional health areas were analyzed with χ² tests.

RESULTS

We identified 1716 cases of DDH of 258 499 newborns. The incidence of DDH was calculated at 6.6/1000 newborns. Late-presenting DDH was detected in 2.2/1000 newborns. Female first-born children, clubfoot deformity, and breech position were associated significantly with an increased risk. Children with DDH born in rural areas of the Northern and Central part of Manitoba presented at a later age than those who are born in the urban areas (P < .0001) CONCLUSION: This study shows the need for improved early detection and awareness at well-baby clinics of risk factors and regional differences for DDH.

Hip dysplasia in the young adult caused by residual childhood and adolescent-onset dysplasia

Hip dysplasia is a treatable developmental disorder that presents early in life but if neglected can lead to chronic disability due to pain, decreased function, and early osteoarthritis. The main causes of hip dysplasia in the young adult are residual childhood developmental dysplasia of the hip (DDH) and adolescent-onset acetabular dysplasia. These two distinct disease processes affect the growing hip during different times of development but result in a similar deformity and pathomechanism of hip degeneration. Routine screening for DDH and counseling regarding risks for acetabular dysplasia in families with a history of early hip osteoarthritis may allow early identification and intervention in these hips with anatomical risk factors for joint degeneration.

The prevalence of dysplasia in femoroacetabular impingement

It is unknown how often femoro-acetabular impingement (FAI) and hip dysplasia co-exist and which is more important in the development of intra-articular lesions such as labral tears. This study identified the prevalence of dysplasia on standard radiographs in a group of 76 consecutive patients with symptomatic FAI. The centre-edge (CE) angle of Wiberg, the acetabular angle (AA) of Sharp, FAI type, offset ratio and posterior wall sign were identified. 63 patients, predominantly young adult males (mean age: 34.6 years; 10:4 male-to-female ratio), met our inclusion criteria. Most females (13:18) showed signs of dysplasia based on the AA. No association of dysplasia with FAI group, offset ratio or posterior wall sign was found. 47% of our patients with FAI also had radiographic evidence of dysplasia (3-15% definite and 9-30% borderline, depending on the angle utilised). Surgery for FAI should therefore take into account the presence of co-existing dysplasia. Conversely, surgery for dysplasia should take into consideration the co-existence of FAI. The prime cause of labral pathology in the presence of dysplasia may be co-existent FAI and the latter problem may demand priority, not the former.

[Congenital hip dysplasia, screening and therapy]

Congenital hip dysplasia and hip dislocation are relatively common pathological conditions of the musculoskeletal system in infants. An early and certain diagnosis can now be achieved by sonographic hip screening within the framework of screening examination programs. This early diagnostic procedure in infants is essential particularly for a conservative treatment strategy. Therefore, apart from possessing in-depth knowledge, training of the examiner in specialist courses is of central importance. This article presents an overview of the entity of congenital hip dysplasia and hip dislocation, the diagnostics and treatment with special emphasis on recent developments.

Effect of maternal and treatment-related factors on the prevalence of birth defects after PESA-ICSI and TESE-ICSI: a retrospective cohort study

INTRODUCTION

We performed a retrospective cohort study with the aim to evaluate the effect of maternal and treatment-related factors on the prevalence of birth defects after intracytoplasmic sperm injection (ICSI) using percutaneous epididymal sperm aspiration (PESA) and testicular sperm extraction (TESE).

MATERIAL AND METHODS

643 newborns born after PESA-ICSI (n = 406) and TESE-ICSI (n = 237) in Radboud University Medical Center, after a gestational age of 12 weeks, 1 January 2002-1 January 2011 and 1 March-1 November 2014, respectively, were included in this study. Three sources of data were used for analysis: questionnaires, national obstetrics registration forms, and a lab-database of all ICSI treatments. Data were analyzed using generalized estimating equations and logistic regression analysis.

RESULTS

The prevalence of major birth defects in newborns born after PESA-ICSI was 6.9% and after TESE-ICSI was 5.9% (odds ratio 0.89, 95% confidence interval 0.46-1.75). No significant association was found between maternal or treatment-related factors and the prevalence of birth defects.

CONCLUSIONS

We found a similar overall prevalence of birth defects in newborns born after PESA-ICSI and TESE-ICSI. The maternal and treatment-related factors investigated did not show a significantly increased cumulative risk of birth defects.

Possible association of single nucleotide polymorphisms in the 3' untranslated region of HOXB9 with acetabular overcoverage

OBJECTIVES

Excessive acetabular coverage is the most common cause of pincer-type femoroacetabular impingement. To date, an association between acetabular over-coverage and genetic variations has not been studied. In this study we investigated the association between single nucleotide polymorphisms (SNPs) of paralogous Homeobox (HOX)9 genes and acetabular coverage in Japanese individuals to identify a possible genetic variation associated with acetabular over-coverage.

METHODS

We investigated 19 total SNPs in the four HOX9 paralogs, then focused in detail on seven of those located in the 3' untranslated region of HOXB9 (rs8844, rs3826541, rs3826540, rs7405887, rs2303485, rs2303486, rs79931349) using a case-control association study. The seven HOXB9 SNPs were genotyped in 316 subjects who had all undergone radiological examination. The association study was performed by both single-locus and haplotype-based analyses.

RESULTS

The genotype and allele frequencies of the five HOXB9 SNPs showed significant association with acetabular over-coverage compared with controls (rs7405887 OR = 3.16, p = 5.29E-6, 95% CI 1.91 to 5.25). A significant difference was also detected when haplotypes were evaluated (OR = 2.59, p = 2.61E-5, 95% CI 1.65 to 4.08). The two HOXB9 SNPs (rs2303485, rs2303486) were associated with decreased acetabular coverage (rs2303485 OR = 0.524, p = 0.0091, 95% CI 0.322 to 0.855; rs2303486 OR = 0.519, p = 0.011, 95% CI 0.312 to 0.865).

CONCLUSIONS

The five HOXB9 SNPs (rs8844, rs3826541, rs3826540, rs7405887, rs79931349) were associated with acetabular over-coverage. On the other hand, the two SNPs (rs2303485 and rs2303486) were associated with the lower acetabular coverage. The association of rs2303486 would be consistent with the previous study. Therefore, the HOXB9 SNPs might be involved in the morphogenesis of acetabular coverage, and could be an independent risk factor for developing pincer-type femoroacetabular impingement. Cite this article: Bone Joint Res 2015;4:50-5.

Natural history of hip instability in infants (without subluxation or dislocation): a three year follow-up

BACKGROUND

The natural history of hip instability (without subluxation or dislocation) and treatment in infants remain controversial. We performed a retrospective cohort case-only study with blinded, prospectively collected data to assess normalization of the acetabular index in consecutive untreated infant hips with sonography instability.

METHODS

Consecutive hips meeting inclusion criteria were followed by sonography/radiography and data analyzed using tabular and regression models.

RESULTS

In 48 hips, acetabular index measured by radiography normalized within 3 years of age without treatment. Normalization by age occurred: 7 months in 35%, 12 months in 67%, 18 months in 75%, 24 months in 81%, and 36 months in 100%. Two patterns of normalization of the acetabular index were observed: group I showed ossification in a physiological range of normal by 7 months of age, and group II had delayed ossification with later normalization of the acetabular index measurement. Breech presentation (p =0.013) and cesarean delivery (p =0.004) statistically directly correlated with a later normalization.

CONCLUSIONS

The natural history of infant hip instability (without subluxation or dislocation), which is reduced at rest and unstable with stress as diagnosed by the Harcke method of sonography, has spontaneous normalization of the acetabular index within 3 years of age. We suggest three patterns of acetabular ossification in unstable infants' hips: (I) normal ossification, (II) delayed ossification with normalization of the acetabular index by age 3 years, and (III) defective secondary centers of ossification with an upward tilt of the lateral acetabular rim in adolescence.