Perinatal risk factors for developmental dysplasia of the hip

Developmental Dysplasia of the Hip: Factors Related to the Diagnosis and Characteristics of Selective Screening for its Detection

Backgrounds

Breech presentation, family history, and physical examination are the most recognized risk factors for DDH, which form the basis of selective screening. However, this approach can lead to late diagnosis, invasive treatments, and complications. This study analyzes the effectiveness of selective screening and identifies additional factors related to DDH.

Methods

A retrospective case-control analytical study is designed, including children who are assessed through screening between 2012 and 2019. The variables examined include clinical and gestational characteristics, as well as examination findings. Descriptive analysis is conducted, followed by univariate analysis using Chi-squared, Fisher's exact, or Student's T tests. For multivariate analysis, the "all set" user command is employed. Sensitivity, specificity, and ROC curve are calculated, with a significance level set at p < 0.05. StataIC 16 and SAS System 9.4 are used.

Results

762 children are included in the study, of which 33 are diagnosis with DDH. A total of 8,191 models are developed to predict DDH. The best logistic regression model identified the following independent predictors of dysplasia: newborn weight (OR 1.2, 95% CI 1.1-1.4), female sex (OR 3.9; 95% CI 1.4-10.9), cephalic presentation (OR 17.8; 95% CI 2.3-137.3), primiparity (OR 2.6; 95% CI 1.1-5.7), and examination (OR 149.6; 95% CI 18-1121.4). This model correctly classifies 83.6% patients (ROC curve 0.86). In selective screening, examination is the only identified risk factor for DDH, yet its sensitivity does not exceed 10%.

Conclusions

This study proposed a total of 8191 models to predict DDH. The identified predictors include female sex, birth weight, cephalic presentation, and primiparity. While physical examination is the primary risk factor, it detects only decentred hips. The low sensitivity of selective screening raises questions about whether it remains the most appropriate method for identifying DDH in current practice.

Impact of Pavlik Harness treatment on motor skills acquisition: A case-control study

Purpose

Our purpose was to analyze the impact of Pavlik Harness treatment on children motor skills development, comparing to a control group.

Methods

A total of 121 children were included: 55 cases (children with Developmental Dysplasia of the Hip) and 66 healthy controls. Cases were recruited from 2017 to 2021 and followed up to 2022. Controls (healthy children without orthopedic pathology) were recruited from 2020 to 2022. The primary endpoint was the time of achievement of three gross motor milestones (sitting without support, hands-and-knees crawling, and walking independently).

Results

The groups had no differences regarding sex distribution, gestational age, birth weight, and rate of twin pregnancy. The prevalence of positive family history of Development Dysplasia of the Hip (20.0% vs 3.0%, p < 0.003), breech presentation (38.2% vs 1.5%, p < 0.001), and C-section delivery (60.0% vs 19.7%, p < 0.001) was significantly higher in Development Dysplasia of the Hip group. Children with Development Dysplasia of the Hip achieved the three gross milestones evaluated 1 month later than healthy controls, although this was not statistically significant (p = 0.133 for sitting, p = 0.670 for crawling, and p = 0.499 for walking).

Conclusion

Children with Development Dysplasia of the Hip, treated by Pavlik harness, do not have significant delays in motor skills acquisition.

Validation of parameters recommended for secondary screening for developmental dysplasia of the hip in Japan

BACKGROUND

Based on the Japanese Pediatric Orthopaedic Association's guidelines, secondary screening and imaging including ultrasonography and radiography, are recommended in infants with limited hip abduction (<70°) or in those with multiple risk factors including the following: asymmetrical skin creases, a family history of developmental dysplasia of the hip, female sex, and pelvic position at delivery. However, there is still little information regarding the usefulness of this guideline. The objective of this study was to investigate the association between the risk factors and developmental dysplasia of the hip diagnosed using ultrasound and radiography.

METHODS

A total of 356 infants (67 boys and 289 girls) underwent secondary ultrasonographic and radiological screening for developmental dysplasia of the hip in our hospital. Risk factors were documented from their medical records. The recommended item score, which we defined as an integrated value of the recommended item, was calculated for each patient. The limitation of hip abduction alone was a criterion for secondary screening; therefore, we defined the scores as follows: the limitation of hip abduction scored 2 points and other recommended scores were assigned 1 point. If the recommended item score was 2 points or more, we classified the infants as high-risk.

RESULTS

A total of 280 of 356 infants were included in the high-risk group, which showed a higher ratio of cases with abnormal imaging findings than the low-risk group. According to the multivariate logistic regression analyses among the recommended items, being female, skin asymmetry, and limb limitation were identified as independent risk factors for imaging abnormality and the need for Pavlik harness treatment.

CONCLUSIONS

The recommended items for secondary screening based on the Japanese Pediatric Orthopaedic Association's guidelines could be useful for screening infants in need of treatment.

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.

Risk factors of developmental dysplasia of the hip in infants: A meta-analysis based on cohort studies

INTRODUCTION

Developmental dysplasia of the hip (DDH) is a prevalent condition in children. Currently, the exact etiology of DDH remains uncertain. The objective of this study was to conduct a meta-analysis to investigate the risk factors associated with DDH in infants. The findings would provide a theoretical foundation for targeted early screening and diagnosis.

HYPOTHESIS

Several indicators, such as gender, intrauterine position, family history of DDH, gestational age, delivery mode, amniotic fluid levels, swaddling, parity, fetus number, combined musculoskeletal deformities, birth weight, and physical examination results, may serve as risk factors for DDH.

MATERIALS AND METHODS

Cohort studies investigating the risk factors of DDH in infants through logistic regression analysis were searched in the Wanfang, VIP citation, China National Knowledge Infrastructure (CNKI), China Biology Medicine disc, Excerpta Medica Database (Embase), PubMed, and Cochrane Library databases up to May 2023. After extracting the data from eligible literature and assessing them using the Newcastle-Ottawa Scale (NOS), articles were selected based on pre-established inclusion and exclusion criteria.

RESULTS

A total of eleven literature reports covering 979,757 infants were included in this meta-analysis. The publication bias did not significantly influence the results. The incidence rate of DDH was 47.99‰ among infants with risk factors compared to 3.21‰ in the general population. Risk factors for DDH included being female (OR=6.97, 95% CI: 5.18-9.39, p<0.001), breech delivery (OR=4.14, 95% CI: 3.09-5.54, p<0.001), positive family history (OR=4.07, 95% CI: 2.20-7.52, p<0.001), cesarean section (OR=1.11, 95% CI: 1.01-1.21, p=0.032), oligohydramnios (OR=3.93, 95% CI: 1.29-12.01, p=0.016), swaddling (OR=6.74, 95% CI: 1.25-36.31, p=0.026), firstborn status (OR=1.84, 95% CI: 1.49-2.53, p<0.001), combined musculoskeletal malformations (OR=2.27, 95% CI: 1.58-3.27, p<0.001), and physical signs of DDH (OR=8.71, 95% CI: 2.44-31.07, p=0.001). Premature delivery (OR=0.91, 95% CI: 0.88-0.95, p<0.001) was a protective factor for DDH. The relationship between multiple pregnancies (OR=0.58, 95% CI: 0.33-1.02, p=0.060) and low birth weight (OR=0.62, 95% CI: 0.14-2.76, p=0.529) in relation to DDH remained uncertain.

DISCUSSION

This meta-analysis shows that female, breech delivery, positive family history, cesarean section, firstborn status, oligohydramnios, swaddling and combined musculoskeletal malformations are associated with DDH. Premature delivery appeared to be a protective factor against DDH. Nevertheless, the other factors need more research to reach more conclusive results.

LEVEL OF EVIDENCE

III; meta-analysis.

The usefulness of universal ultrasound before hospital discharge for early diagnosing hip dysplasia in Korean neonates with breech presentation in a single center: A retrospective study

Developmental dysplasia of the hip (DDH) is a broad-spectrum disorder. Early diagnosis and treatment are important for improved prognosis and a lower risk of long-term complications. Selecting high-risk infants is important for the early diagnosis of DDH using ultrasonography; however, there are no standard international guidelines. This study aimed to identify the usefulness of universal ultrasound before hospital discharge in breech-born neonates and proposes selective ultrasound for high-risk patients. A retrospective chart review was conducted to identify breech-born neonates who underwent hip ultrasonography before discharge for the detection of DDH between 2019 and 2023. Patients were categorized into DDH and non-DDH groups according to the ultrasound results. We compared sex, gestational age, birth weight, first-born status, twin pregnancy, associated anomalies, presence of symptoms, physical examination results, and timing of the first hip ultrasound. The medical records of the mothers were reviewed to identify the amount of amniotic fluid and duration of breech presentation. This study included 102 patients, of whom 62 and 40 were assigned to the non-DDH and DDH groups, respectively. Congenital anomalies, positive symptoms, and positive physical examination results were significant risk factors. However, female sex, first-born status, and oligohydramnios were not statistically significant. The duration of breech presentation during pregnancy was not significant. Additionally, the risk of Pavlik harnesses was higher in patients who underwent a positive physical examination. Universal ultrasonography before discharge is not recommended for the early diagnosis of DDH in all breech-born neonates because of the high rate of overdiagnosis. We recommend that ultrasonography be performed in patients with congenital anomalies, except for foot problems, or in those with a positive physical examination conducted by trained specialists.

Isthmocele and Infertility

Isthmocele is a gynecological condition characterized by a disruption in the uterine scar, often associated with prior cesarean sections. This anatomical anomaly can be attributed to inadequate or insufficient healing of the uterine wall following a cesarean incision. It appears that isthmocele may impact a woman's quality of life as well as her reproductive capacity. The incidence of isthmocele can range from 20% to 70% in women who have undergone a cesarean section. This review aims to sum up the current knowledge about the effect of isthmocele on fertility and the possible therapeutic strategies to achieve pregnancy. However, currently, there is not sufficiently robust evidence to indicate the need for surgical correction in all asymptomatic patients seeking fertility. In cases where surgical correction of isthmocele is deemed necessary, it is advisable to evaluate residual myometrial thickness (RMT). For patients with RMT >2.5-3 mm, hysteroscopy appears to be the technique of choice. In cases where the residual tissue is lower, recourse to laparotomic, laparoscopic, or vaginal approaches is warranted.

The risk of DDH between breech and cephalic-delivered neonates using Graf ultrasonography

PURPOSE

Developmental dysplasia of the hip (DDH) is one of the most common musculoskeletal disorder in infants. The most significant risk factors include female gender, breech presentation, left hip and family history. In this study, we utilized the Graf method at different time intervals to evaluate both breech-delivered and cephalic-born newborns. The objectives were to compare the incidence of DDH in cephalic and breech-delivered neonates and investigate whether the hip joints of neonates delivered in the breech position exhibit a distinct maturation pattern.

MATERIAL AND METHODS

We studied prospectively 618 hip joints (309 newborns). Each hip joint was examined with the Graf method in four time periods as follows: Phase #1 (0-1 weeks), Phase #2 (1-4 weeks), Phase #3 (4-7 weeks), and Phase #4 (7-10 weeks). The α and β angles for each hip joint were measured, and the hips were classified according to Graf classification. With our statistical analysis within the different phases, we were able to investigate potential variations in the maturation patterns between newborns delivered in the breech and cephalic delivery positions.

RESULTS

A significant difference (at the 5% level) was observed in Phase 1 between breech and cephalic-delivered neonates (35.6-8.6%). This difference tended to decrease in next phases (13.6-1% in Phase 2, 2.5-0% in Phase 3 and 1.7-0% in Phase 4). A significant difference (at the 5% level) for cephalic-delivered neonates was also observed between Phase 1 and Phase 4 (8.5-0%), but the percentages were low. Additionally, the breech-delivered had extreme difference in incidence of DDH from Phase 1 to Phase 4 (35.6-11.9%, 2.5%, and 1.7%, respectively).

CONCLUSION

It appears that there is an actual difference in the incidence of DDH between breech-delivered and cephalic-delivered neonates, although the difference may be less significant than previously considered. The majority of the breech-delivered neonates that were initially considered as pathological (Phase 1) are, in fact, healthy. This is ascertained in subsequent ultrasound examinations conducted in later phases (Phases 2-4), when the incidence of pathological cases decreases. This could be attributed to potential different maturation pattern between these groups.

Family History of Developmental Dysplasia of the Hip is a Risk Factor for the Progression of Hip Osteoarthritis

BACKGROUND

Developmental dysplasia of the hip (DDH) is considered to have genetic predisposition and presents many intrafamilial occurrences. However, there is no report that evaluates the effect of DDH family history on the progression after the onset of hip osteoarthritis (OA).

METHODS

Medical interviews about detailed clinical information including family history were conducted on 298 consecutive patients who had undergone surgery for OA due to DDH. Clinical or radiographic items that are associated with the severity of DDH (total hip arthroplasty [THA], involvement of bilateral DDH, onset age of hip pain, and three radiological indices of DDH: center-edge angle, sharp angle, and acetabular roof obliquity) were collected and evaluated in multivariate analyses for their associations with DDH family history in a qualitative or quantitative manner. Survival time analyses for THA as the endpoint was also performed to evaluate the effects of DDH family history on the progression of OA.

RESULTS

The DDH family history showed significant associations with bilateral involvement of DDH (odds ratio = 2.09 [95% confidence interval {CI} 1.05 to 4.16]; P = .037), early onset of hip pain (P = .0065), and radiological severity of DDH (P = .016). The DDH family history showed a significant association with undergoing THA (odds ratio = 2.25 [95% CI 1.09 to 4.66]; P = .029), further supported by the Cox regression analyses (hazards ratio = 1.56 [95% CI 1.15 to 2.11]; P = .0044).

CONCLUSION

A DDH family history is a risk factor for the progression of hip OA. Stronger genetic predisposition to DDH leads to faster onset and progression of hip OA.

Birthweight correlates to pubo-femoral distances and α angles in hip ultrasound of newborns at 6 weeks of age: a retrospective cohort study

BACKGROUND AND PURPOSE

There is inconsistency in the literature regarding the relationship between increased birthweight and risk of developmental dysplasia of the hip (DDH). We aimed to investigate the correlation between birthweight and pubo-femoral distance (PFD), as well as Graf's α angle in newborns undergoing hip ultrasound examination at 6 weeks of age.

PATIENTS AND METHODS

Basic newborn characteristics and ultrasound measurements were retrospectively collected during a 1-year study period. We excluded multiple births, newborns born at less than 37 gestational weeks, and incomplete information. Simple and multiple linear regression analyses were performed to evaluate the correlation of birthweight and PFD, and, second, birthweight and α angles including a stratified regression analysis investigating the potential effect modification of sex.

RESULTS

707 newborns (1,414 hips) were included. Mean birthweight was significantly higher for male newborns (P < 0.001). Increased birthweight was positively correlated to PFD values (crude coefficient 0.21, 95% confidence interval [CI] 0.10-0.32) and the correlation was still present after adjusting for sex, family history, and breech presentation (adjusted coefficient 0.18, CI 0.07-0.29). The stratified α angle model for the males was significant for both the crude coefficient (-0.73, CI -1.28 to -0.19) and the adjusted (-0.59, CI -1.15 to -0.03), and also for the females (crude coefficient -1.14, CI -1.98 to -0.31 and adjusted coefficient -1.15, CI -1.99 to -0.31).

CONCLUSION

We found that increased birthweight positively correlated to PFD, and negatively correlated to α angle, but this was not of clinical significance.

The Influence of Risk Factors in the Early Detection of Developmental Dysplasia of the Hip in a Country with Limited Material Resources

Developmental dysplasia of the hip (DDH) is a condition that includes a wide spectrum of anomalies ranging from simple instability with ligamentous hyperlaxity to the complete displacement of the femoral head outside the abnormally developed cotyloid cavity. Early detection and initiation of treatment allow "restitutio ad integrum" healing, which has raised the medical community's interest in early diagnosis. However, in countries with limited material resources, where echographic screening is not performed, efforts are being made to increase the sensitivity of clinical screening. Thus, the concept of "hip at risk" is taking shape worldwide. This is the normal clinical hip, but associated with one or more risk factors. We conducted a retrospective study for the period 2010-2015 with patients who presented in the ambulatory clinic of the St. John Children's Clinical Hospital, Galati. The study included 560 patients, who were all examined clinically and sonographically, according to the Graf method, by a senior orthopedic doctor with competence in hip sonography. The data obtained from the anamnesis, clinical examination, and ultrasound examination were recorded in the DDH file. The goal of the statistical analysis of the group of patients was to find a correlation between DDH and the risk factors used in the clinical detection of this pathology. In the studied group, four risk factors were identified that have an increased association with DDH: female sex, pelvic presentation, limitation of coxo-femoral abduction, and congenital clubfoot; thus, the conclusion of the study is that patients who have at least one of the listed risk factors should be examined sonographically as quickly as possible. The early ultrasound examination will allow the identification of the disease and the initiation of treatment.

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.

Preterm birth does not increase the risk of developmental dysplasia of the Hip: a systematic review and meta-analysis

BACKGROUND

The purpose of this systematic review was to appraise the literature on the association between preterm birth and developmental dysplasia of the hip (DDH).

METHODS

Medline, Embase, Scopus, and Web of Science databases were queried for all studies pertaining to DDH and preterm birth. Data were imported and analyzed in Revman5 and Comprehensive Meta-Analysis (CMA) for pooled prevalence estimation.

RESULTS

Fifteen studies were included in the final analysis. There were 759 newborns diagnosed with DDH in these studies. DDH was diagnosed in 2.0% [95%CI:1.1-3.5%] of the premature newborns. Pooled incidence rate of DDH was not statistically different between those groups (2.5%[0.9%-6.8%] vs. 0.7%[0.2%-2.5%] vs. 1.7%[0.6%-5.3%];Q = 2.363,p = 0.307).

CONCLUSIONS

In this systematic review and meta-analysis, we did not find preterm birth to be a significant risk factor for DDH. Data suggests that female sex and breech presentation are associated with DDH in preterm infants, but the data is scarce in the literature.

A Novel Heterozygous Missense Variant in Parathyroid Hormone 1 is Related to the Occurrence of Developmental Dysplasia of the Hip

Introduction: Developmental dysplasia of the hip (DDH) is one of the most common diseases in the pediatric orthopedics, with an incidence of 1-5%. Genetic factors are the bases of the pathogenesis of DDH, but the pathogenic variants and pathogenesis of DDH are still unknown. There are no key accurate diagnostic or prognostic molecular markers for DDH. The purpose of our study was to screen for genetic variant associated with DDH and explore its pathogenesis. Materials and Methods: The genetic variation of DDH was tested by variant NGS-based exome analyses, verified by the Sanger sequencing. Results: A four-generation family in which DDH was present in three generations was recruited. A novel heterozygous missense variant c.629C>T (p.(Ala210Val)) in exon 7/8 of the parathyroid hormone 1 receptor (PTH1R) gene was identified through screening of two affected and one unaffected family members. The candidate variant was validated in all available family members with all three affected members being positive for the PTH1R variant. Conclusion: Our results are highly supportive of PTH1R as a novel candidate gene for DDH and demonstrated that the combination of pedigree information and next-generation sequencing is an effective method for identifying pathogenic variants associated with DDH.

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.

Universal screening may reduce the incidence of late diagnosis of developmental dysplasia of the hip : a systematic review and meta-analysis

AIMS

We investigated the prevalence of late developmental dysplasia of the hip (DDH), abduction bracing treatment, and surgical procedures performed following the implementation of universal ultrasound screening versus selective ultrasound screening programmes.

METHODS

A systematic search of PubMed, Embase, The Cochrane Library, OrthoSearch, and Web of Science from the date of inception of each database until 27 March 2022 was performed. The primary outcome of interest was the prevalence of late detection of DDH, diagnosed after three months. Secondary outcomes of interest were the prevalence of abduction bracing treatment and surgical procedures performed in childhood for dysplasia. Only studies describing the primary outcome of interest were included.

RESULTS

A total of 31 studies were identified, of which 13 described universal screening and 20 described selective screening. Two studies described both. The prevalence of late DDH was 0.10 per 1,000 live births (95% confidence interval (CI) 0.00 to 0.39) in the universal screening group and 0.45 per 1,000 live births (95% CI 0.31 to 0.61) in the selective screening group. Abduction bracing treatment was performed on 55.54 per 1,000 live births (95% CI 24.46 to 98.15) in the universal screening group versus 0.48 per 1,000 live births (95% CI 0.07 to 1.13) in the selective screening group. Both the universal and selective screening groups had a similar prevalence of surgical procedures in childhood for dysplasia being performed (0.48 (95% CI 0.32 to 0.63) vs 0.49 (95% CI 0.31 to 0.71) per 1,000 live births, respectively).

CONCLUSION

Universal screening showed a trend towards lower prevalence of late DDH compared to selective screening. However, it was also associated with a significant increase in the prevalence of abduction bracing without a significant reduction in the prevalence of surgical procedures in childhood for dysplasia being performed. High-quality studies comparing both treatment methods are required, in addition to studies into the natural history of missed DDH.Cite this article: Bone Joint J 2023;105-B(2):198-208.

The economics of patients undergoing periacetabular osteotomy for hip dysplasia: the financial relationship between physicians and hospitals

Periacetabular osteotomy (PAO) is the gold standard for treating hip dysplasia in patients with preserved articular cartilage. The aim of this study is to evaluate the financial relationship between facility and professional revenue for patients undergoing PAO for hip dysplasia and acetabular version abnormalities. All patients who underwent PAO for hip dysplasia by a single surgeon at a tertiary academic medical center between December 2016 and November 2020 were identified. Financial records for facility and professional services were reviewed and analyzed. The orthopedic charge multiplier, the dollars of facility charge created by a single dollar of orthopedic professional charge, and orthopedic net revenue multiplier, the dollars collected by the hospital for facility services generated for each dollar collected by the orthopedic surgeon, were calculated. A total of 36 patients were included in the study. The mean total charge for all patients was $144 939.35 ± $23 726.48 (range $109 002.71 to $227 290.20), and the average total revenue for all patients was $44 218.79 ± $12 352.97 (range $29 397.39 to $90,830.62). The mean orthopedic charge multiplier was 2.47 ± 1.32 (range 0.78-6.53), and the net revenue collection multiplier was 8.62 ± 10.69 (range, 1.20-57.80). The majority of charges and revenue related to care of patients undergoing PAO return to the hospital. The significant mean orthopedic charge multiplier for this procedure increases the value of the service and the surgeon to hospital profitability. This information can help shape the relationship between the hospital and the surgeon and create a firm platform to advocate for program advancement.

Factors for selective ultrasound screening in newborns with developmental dysplasia of the hip (DDH)

Background

Hip ultrasound screening for DDH provides better sensitivity compared to physical examination. Due to a lower prevalence and limited resources, selective hip ultrasound in newborns at risk could be considered a proper screening protocol in Thailand and Asian countries.

Objective

This study was aimed to evaluate risk factors and define criteria for selective screening.

Methods

A case-control study was conducted in 2020. All newborns with hip ultrasound screening were included. Cases were defined as newborns with abnormal hip ultrasounds, while controls were those with normal studies. Inter and intra-rater reliability were evaluated. All factors were analyzed using univariate and multivariate logistic regression. The model performance was tested by Hosmer-Lemeshow goodness of fit. Internal validity was performed by the split data method. Area under the receiver operating characteristic (ROC) curve was estimated.

Results

Ninety-five newborns (29 cases and 66 controls) were included. Eighty percent of cases and 58% of controls were female. The gestational age was 36.6 and 37.7 weeks in case and control, respectively. Female, breech presentation, positive Ortolani test, positive Barlow test, and limited hip abduction were significant factors with odds ratio of 2.82, 5.12, 34.21, 69.64, and 5.48, respectively. The final model included breech presentation, positive Ortolani test, and positive Barlow test. The model cut-off value 15.02 provided sensitivity (93.10%) and specificity were (80.30%). The area under the ROC curve was 0.9308. The split data remained significant internal validity for all factors with p-value &lt; 0.05.

Conclusion

Careful history taking and physical examination are essential to identify the risk factors for DDH. Newborns with breech presentation, positive Ortolani test and positive Barlow test should be screened by hip ultrasound.

Evaluation of CX3CR1 gene DNA methylation in developmental dysplasia of the hip (DDH)

INTRODUCTION AND OBJECTIVE

Developmental dysplasia of the hip (DDH) is a musculoskeletal disorder. Genetic and epigenetic changes in C-X3-C motif chemokine receptor 1 (CX3CR1) may lead to disturbance in chondrocyte development and change the labrum dimensions, which indirectly result in hip joint instability. Considering the important role of this gene in cell migration, cell adhesion and bone and cartilage development, we aimed to evaluate the CX3CR1 gene methylation in DDH pathogenesis.

METHODS

Our study comprised of forty-five DDH patients and forty-five healthy control subjects with healthy femoral neck cartilage. The healthy controls had total or hemiarthroplasty for the femoral neck fracture. Samples were collected from the femoral head (cartilage) of DDH patients and healthy controls. Genomic DNA was obtained from the samples, and DNA methylation of CX3CR1 gene was analyzed via metabisulfite method.

RESULTS

Methylation analysis reveals no significant differences in promoter of CX3CR1 gene in cartilage samples from DDH patients and healthy control subjects (P = 0.33).

CONCLUSION

Methylation status of CX3CR1 gene showed no significant difference between the patient and control groups. Our results indicate that DNA methylation may not modulate this gene in this disease and other epigenetic mechanisms such as non-coding RNAs and histone modifications could be implicated.

[Treatment of hip dysplasia in young adults]

Developmental dysplasia of the hip (DDH) is one of the most common disorders of hips in children. The deformity can remain asymptomatic into adolescence and adulthood; however, it is considered to be a form of prearthritis and is the main cause of premature osteoarthritis of the hip. The deformity affects the acetabulum but can also be accompanied by changes in the shape of the proximal femur. If conservative treatment for mild DDH is insufficient, or in cases of moderate to severe DDH, operative treatment should be carried out, for example by corrective osteotomy of the pelvis and/or the proximal femur and hip arthroscopy may be considered adjunctively in order to resolve the prearthritis and prevent premature osteoarthritis of the hip. This manuscript elucidates the deformity, the diagnostic measures required to make the diagnosis and the treatment options available for prevention of arthritis.

Developmental Dysplasia of the Hip: Guide for the Pediatric Primary Care Provider

Developmental dysplasia of the hip (DDH) is the most common congenital abnormality in newborns. Untreated DDH can cause significant impairments, including chronic hip pain, osteoarthritis, limb length discrepancy, altered gait, and joint contractures. Treatment outcomes are significantly worse with increasing delay in presentation, making early screening and detection critical. The purpose of this review is to provide a comprehensive guide for the pediatric primary care provider on the cause, diagnosis, and management of DDH. Screening practices, physical examination, imaging modalities, and treatment will be discussed. A missed hip dislocation in a walking-age child is a devastating but preventable event; pediatric primary care providers should have a high index of suspicion for DDH and promptly refer any patient with concerning findings to a pediatric orthopedic surgeon. [Pediatr Ann. 2022;51(9):e346-e352.].

Impact of Multiple Factors on the Incidence of Developmental Dysplasia of the Hip: Risk Assessment Tool

Background and Objectives: Developmental dysplasia of the hip (DDH) is one of the most common musculoskeletal conditions in children. If not treated, it leads to disability, gait abnormalities, limb shortening, and chronic pain. Our study aims to determine the impact of multiple risk factors on the incidence of DDH and to develop an interactive risk assessment tool. Materials and Methods: We conducted a retrospective cohort study in the Outpatient Clinic for Children of the Medical University of Warsaw Hospital. The Graf classification system was used for universal ultrasonographic screening. In total, 3102 infants met the eligibility criteria. Results: The incidence of DDH in the study group was 4.45%. The incidence of DDH in the Warsaw population, Poland, during the study period was 3.73 to 5.17 (95% CI). According to the multivariate analysis, the risk factors for DDH were birth weight (OR = 2.17 (1.41−3.32)), week of delivery (OR = 1.18 (1.00−1.37)), female sex (OR = 8.16 (4.86−13.71)), breech presentation (OR = 5.92 (3.37−10.40)), physical signs of DDH (25.28 (8.77−72.83)) and positive family history in siblings (5.74 (2.68−12.31)). Our results support the recent hypothesis that preterm infants (<37 weeks) have a lower rate of DDH. Conclusions: A multivariate logistic regression predictive model was used to build the risk calculator. The DDH risk calculator will be evaluated in a prospective validation study.

Asymmetry in Muscle Strength, Dynamic Balance, and Range of Motion in Adult Symptomatic Hip Dysplasia

Hip dysplasia (HD) is a typical developmental abnormality of the hip joint, and discomfort is often found in adulthood. This study compared patients with symptomatic HD in muscle strength, dynamic balance, and range of motion (ROM) with healthy individuals. Patients included those who complained of unilateral pain although the lateral center edge angle (LCEA) exhibited bilateral abnormality. Participants (n = 95; men: 46, women: 49) were divided into symptomatic and asymptomatic sides, and a healthy group without a history of hip joint disease (n = 70; men: 30, women: 40) was compared. Hip flexion, extension, abduction, and adduction were performed at an angular velocity of 30°/s using an isokinetic strength test device. The Y-balance test was conducted to measure dynamic balance, and ROM was measured using an electronic goniometer to evaluate flexion, extension, adduction, abduction, and internal and external rotations. In addition, the pain visual analog scale (VAS) and hip and groin outcome scale (HAGOS), a subjective evaluation of the hip joint, were evaluated. ROM (flexion, abduction, internal rotation, and external rotation) was significantly decreased in the HD symptomatic sides of men and women compared to those of the healthy group and the asymptomatic side, and the dynamic balance, flexion, and abduction muscle strength were also lower on the symptomatic sides. Although the LCEA of the HD asymptomatic side was lower than that of the healthy group, there were no significant differences in VAS, flexion, extension, abduction ROM, and extension strength compared to those of healthy individuals. In conclusion, patients with HD were mostly bilateral, and on the symptomatic side, there was a decrease in ROM, dynamic balance, and muscle strength; however, on the asymptomatic side, the function was relatively close to normal.

Establishment of pediatric developmental dysplasia of the hip biobank: Shanghai children's hospital experience

Developmental dysplasia of the hip (DDH) is a debilitating condition that affects 1–7% of newborns. Children with DDH, not treated early and effectively, will easily lead to disability. A better understanding of the biology of DDH is critical to the development of prognostic biomarkers and novel therapies. The purpose of this study was to establish a biobank of DDH genetic resources, to facilitate clinical and basic scientific research. The biological specimen and clinical data of DDH were collected in Shanghai Children’s Hospital from 2014 to 2021. The collection of blood samples was performed at definitive diagnosis and review, tissue specimens were performed at definitive surgery. The clinical data was collected at the whole stage of DDH patients at diagnosis, treatment and follow-up. A total of 528 patients with DDH were enrolled in this study, 90 were men and 438 were women, with the mean age of 4.67 years. The numbers of tissue and blood specimens reached 2172 and 1490, respectively. The quality test results showed that the DNA concentration decreased slightly with the extension of storage time, but the DNA purity did not change. Meanwhile, the extension of storage time slightly affected the stability of protein of tissue samples but did not affect the expression of the housekeeping gene. The DDH biobank built has the potential of monitoring disease pathogenesis and progress, which could provide specimens to the researchers improving the biological understanding and provide guidance of clinical treatment of this disease to clinicians.

Developmental Dysplasia of the Hip: Prevalence and Correlation with Other Diagnoses in Physiotherapy Practice-A 5-Year Retrospective Review

(1) Background: The objective of this study was to assess the prevalence of Developmental Dysplasia of the Hip (DDH) as a primary or secondary diagnosis during physiotherapy practice. No other studies have investigated the prevalence and associations of DDH within the practice of pediatric rehabilitation. (2) Methods: This retrospective review was performed on 12,225 physiotherapy referrals to the King Abdullah Specialized Children’s Hospital (KASCH), Riyadh, Kingdom of Saudi Arabia, from May 2016 to October 2021. Only DDH referrals for conservative treatment were included in the study. The plan for brace treatment was carried out by the pediatric orthopedics clinic in KASCH. The diagnostic methods were either a pelvic radiograph or ultrasound, depending on the participant’s age. DDH is considered one of the most common secondary complications for children with other medical diagnoses. (3) Results: The most common indication for referral was neurological diagnosis (44%), followed by orthopedic (28%), genetic (19%), cardiac (5%), ophthalmologic (3%), dermatologic (1%) and rheumatologic (0.5%) diagnoses. (4) Conclusion: The prevalence of DDH among all referrals in this study was 6%. In physiotherapy practice, neurologic, genetic, and orthopedic primary or secondary diagnoses were the most prevalent when DDH referrals were investigated. A relatively high prevalence of DDH in the pediatric rehabilitation clinic at KASCH in Riyadh was reported in this study.

Perception and Awareness about Developmental Dysplasia of the Hip in Children among Pregnant Ladies in the Aseer Region, Southwestern Saudi Arabia

Background: Developmental dysplasia of the hip (DDH) is classified as a group of malformations, varying from abnormal acetabulum (dysplasia) and mild subluxation of the femoral head to fixed displacement (congenital dislocation). This study aimed to assess the knowledge level and its determinants regarding DDH in children among pregnant females in the Aseer region of southwestern Saudi Arabia. Methods: A descriptive cross-sectional study was conducted targeting all pregnant females in the Aseer region between 1 February 2021 and 1 May 2021. A pre-structured online questionnaire was constructed by the researchers to obtain the participating females’ bio-demographic data (including age, education status, and obstetric history) and awareness regarding DDH. The last section asked for their source of information regarding DDH. Results: A total of 253 pregnant females (aged between 18 and 45 years; mean age = 30.5 ± 10.2 years) fulfilling the inclusion criteria completed the study questionnaire. About 5% of the females reported having a child with DDH, and 166 (65.6%) pregnant females knew about DDH. Additionally, 110 (43.5%) females reported that they know about how DDH is treated, and 99 (39.1%) knew about DDH complications. The most commonly reported source of information was relatives and friends (44.3%), followed by social media (11.9%) and study and work (7.1%). Conclusions: Pregnant females in the Aseer region have poor knowledge and awareness about DDH and its causes, treatment modalities, and complications. Higher knowledge was associated with either high parity or having a child with DDH.

Does the COVID-19 pandemic cause late diagnosis and delay in treatment in developmental dysplasia of hip patients?

BACKGROUND

The aim of the current study was to search the effect of COVID-19 restriction on developmental dysplasia of hip (DDH) screening.

MATERIAL AND METHODS

We retrospectively reviewed the patients who brought to DDH screening in April-May and June-July 2020 and compared with the same period of 2019. We recorded age, gender, DDH type and risk factors of the patients.

RESULTS

The number of patients taken for DDH screening was 430 and 400 in April-May 2019 and June-July 2019, respectively. In 2020, the number of patients taken for DDH screening was 159 and 776 in the same period, respectively. Thirteen patients were diagnosed with DDH older than 3 months age in June-July 2020. There were only two patients in same period in 2019. In 2020, 6 of 13 patients who applied to the hospital late for the routine US and had pathologic hips were not taken to orthopaedics or follow-up by their families.

CONCLUSION

In the era of COVID-19, the number of late diagnosis and lost follow-up for DDH are increased. To prevent future morbidities and reduce surgical interventions, special measures should be taken.

Developmental Dysplasia of Hip and Post-natal Positioning: Role of Swaddling and Baby-Wearing

INTRODUCTION

Traditional swaddling, which implies restrictive immobilisation of the infant's lower limbs with the hips in forced extension and adduction, has been shown to be a risk factor for Developmental Dysplasia of Hip (DDH).

METHODS

We reviewed the literature regarding the correlation between DDH and post-natal positioning by swaddling and baby-wearing, to draw awareness of healthcare professionals towards an important risk factor for DDH that has often been overlooked.

RESULTS

There is overwhelming evidence in the literature, by both experimental and clinical studies, that proves the close association between improper post-natal positioning of the baby's hips in extension-adduction and an increased incidence of DDH. On the other hand, "hip safe" swaddling which allows unrestricted flexion-abduction movements of the infants' hips, and the use of baby-wearing devices which keep the lower limbs in an attitude of hip flexion-abduction and knee flexion, is optimal for hip development. Populations which practice these "hip-safe" techniques of infant immobilisation have a lower incidence of DDH as compared to those which practice restrictive immobilisation. Furthermore, populations which have adopted "hip-safe" positioning have demonstrated a significant decrease in the incidence of DDH. Understanding this association is vital, since this is a modifiable risk factor, rectification of which can decrease the incidence of DDH.

CONCLUSION

Policy makers and governments must design educational campaigns tailored to their respective populations to increase awareness regarding the benefits of "hip-safe" techniques of infant positioning, since this simple intervention has the potential of decreasing the incidence of DDH.

There is No Link Between Birth Weight and Developmental Dysplasia of the Hip

AIMS

Developmental Dysplasia of the Hip (DDH) has been linked to high birth weight and packaging disorders, though the evidence is limited. This has implications on screening strategies. The aim of this study was to establish whether birth weight was truly associated with the incidence of DDH.

PATIENTS AND METHODS

This cohort study analysed the birth weights of all babies born at our institution over a 24 month period, between 01/01/2017 and 01/01/2019. Babies with DDH and those without DDH were compared. Babies were excluded if born before 38 weeks, had incomplete data or were a non-singleton pregnancy. Sub-analysis was performed for DDH severity (dysplastic versus subluxed/dislocated hips), breech presentation, gestational age, gender and ethnicity. Statistical analysis was performed using SPSS.

RESULTS

There were 10,113 babies born at our institution during the selected timeframe, of which 884 were excluded for prematurity, 336 for being non-singleton and 19 for incomplete data. This left 8874 for analysis, of which 95 babies had confirmed DDH. Both the Non-DDH and DDH data sets had normal distribution (Shapiro-Wilkes, p = 0.308 and 0.629, respectively), with mean birth weights of 3477.7 g with DDH and 3492.8 g without DDH. No difference in birth weight was found (Independent T test, p = 0.789). Females had a lower birth weight than males (3293.1 g versus 3416.6 g (p < 0.001)) yet have a higher incidence of DDH (ratio 6:1 in this dataset). No significant difference was found between birth weights of females with and without DDH (p = 0.068), nor between males with and without DDH (p = 0.513). There were no significant differences in birth weights even when only displaced hips were analysed (p = 0.543), nor according to breech presentation (p = 0.8). Longer gestation babies weighed more (p < 0.00001), yet showed no increase in DDH incidence (p = 0.64).

CONCLUSION

This study discredits the belief that DDH may be related to higher birth weight, thus casting doubt on the link to DDH being a packaging problem in utero. This, therefore, allows future research to prioritise the investigation of alternative aetiologies.

The Term Newborn: Postnatal Screening and Testing

Prenatal genetic screening, including evaluation for inherited genetic disorders, aneuploidy risk assessment, and sonographic assessment, combined with a thorough newborn examination and standard newborn screening, including blood, hearing, and congenital heart disease screening, can reveal conditions requiring further evaluation after delivery. Abnormal prenatal or newborn screening results should prompt additional diagnostic testing guided by maternal fetal medicine, perinatal genetics, or pediatric specialists.

Current Evidence about Developmental Dysplasia of the Hip in Pregnancy

In adults, developmental dysplasia of the hip (DDH) represents a spectrum of disorders. It is commonly found in women in routine orthopedic practice. Hip dysplasia is a leading precursor of joint laxity; when untreated, it can contribute to chronic modifications, such as thickening of the pulvinar and ligamentum teres (which can also elongate), hypertrophy of the transverse acetabular ligament, and osteoarthritis. DDH is presumed to be associated with alterations in pelvic morphology that may affect vaginal birth by the reduction in the transverse diameter of the pelvic inlet or outlet. Here, we provide an overview of the current knowledge of pregnancy-associated DDH. We primarily focused on how a surgical DDH treatment might influence the pelvic shape and size and the effects on the mechanism of birth. We presented the female pelvis from the standpoint of bone and ligament morphology relative to a pelvic osteotomy. Then, we described whether the pregnancy was impacted by previous surgical DDH treatments, performed from infancy to adulthood. In conclusion, hip dysplasia is not associated with high-risk complications during pregnancy or with increased difficulty in vaginal delivery.

Secreted frizzled-related protein 3 was genetically and functionally associated with developmental dysplasia of the hip

Background: Developmental dysplasia of the hip (DDH) is the most common joint disease in child orthopedics. Secreted Frizzled-Related Protein 3 (FRZB) plays an important role in joint development. however, no direct association between FRZB and DDH has been demonstrated.

Methods: Analysis of genotype distribution and allele frequency for detected single nucleotide polymorphisms (SNP) of FRZB was performed. FRZB expression was assayed in DDH joint tissues. Further experiments to identify the chondrogenic properties of FRZB were conducted. Potential upstream miRNAs for FRZB were assayed in DDH.

Results: Significant difference in genotype distribution for rs3768842 (OR=1.46, P=0.0081) and rs2242040 (OR=0.65, P=0.0067) was found. DDH joint tissues showed significantly higher FRZB expression. FRZB demonstrated chondrogenic and anti-hypertrophic properties in vitro. FRZB modulated cell adhesion pathway and cell spreading by regulating integrins expressions. Upstream miRNAs regulating FRZB expression were identified in DDH synovial fluid. Experiments indicated that downregulated miRNA-454 caused FRZB upregulation in DDH joint.

Conclusion: Dysregulated FRZB and its loci were associated with DDH. As a Wnt antagonist with chondrogenic properties, FRZB modulated cell adhesion pathway and cell spreading by regulating integrins expressions. FRZB in multiple DDH joint tissues might be mediated by the dysregulated miRNA expression profiles in the joint synovial fluid.

Multi-joint biomechanics during sloped walking in patients with developmental dysplasia of the hip

BACKGROUND

Developmental dysplasia of the hip is characterized by abnormal acetabular and femoral geometries that alter joint loading and increase the risk of hip osteoarthritis. Current understanding of biomechanics in this population remains isolated to the hip and largely focused on level-ground walking, which may not capture the variable loading conditions that contribute to symptoms and intra-articular damage.

METHODS

Thirty young adult females (15 with dysplasia) underwent gait analysis during level, 10° incline, and 10° decline walking while whole-body kinematics, ground reaction forces, and electromyography (EMG) were recorded. Low back, hip, and knee joint kinematics and internal joint moments were calculated using a 15-segment model and integrated EMG was calculated within the functional phases of gait. Dependent variables (peak joint kinematics, moments, and integrated EMG) were compared across groups with a one-way ANOVA with multiple comparisons controlled for using the Benjamini-Hochberg method (α = 0.05).

FINDINGS

During level and incline walking, patients with developmental dysplasia of the hip had significantly lower trunk flexion angles, lumbar and knee extensor moments, and erector spinae activity than controls. Patients with developmental dysplasia of the hip also demonstrated reduced rectus femoris activity during loading of level walking and increased gluteus maximus activity during mid-stance of decline walking.

INTERPRETATION

Patients with developmental dysplasia of the hip adopt compensations both proximal and distal to the hip, which vary depending on the slope of walking. Furthering the understanding of multi-joint biomechanical compensations is important for understanding the mechanism of osteoarthritis development as well as secondary conditions.

Predictors of Hip Dysplasia at 4 Years in Children with Perinatal Risk Factors

While perinatal risk factors are widely used to help identify those at risk for developmental dysplasia of the hip (DDH) within the first 6 to 8 weeks of life, limited data exist about their association with radiographic evidence of dysplasia in childhood. The purpose of this study was to determine which perinatal risk factors are associated with acetabular dysplasia in children who are ≥2 years of age.

Repeated Pelvic Radiographs in Infants, After Harness Treatment for Developmental Dysplasia of the Hip, Carry Very Low Radiation Risk

OBJECTIVE

There are no data on the effect of X-Ray irradiation to the vulnerable pelvic organs of babies during DDH follow-up. This study aims to calculate, for the first time, the radiation exposure to infants during follow-up for DDH harness treatment, and thus quantify the lifetime risk of malignancy.

METHODS

Patients who had completed 5 years' follow-up following successful Pavlik harness treatment were identified from the hospital DDH database. The radiation dose was extracted from the Computerised Radiology Information System database for every radiograph of every patient. The effective dose (ED) was calculated using conversion coefficients for age, sex and body region irradiated. Cumulative ED was compared to Health Protection Agency standards to calculate lifetime risk of malignancy from the radiographs.

RESULTS

All radiographs of 40 infants, successfully treated in Pavlik harness for DDH, were assessed. The mean number of AP pelvis radiographs was 7.00 (range: 6-9, mode: 7). The mean cumulative ED was 0.25 mSv (Range: 0.11-0.46, SD: 0.07). This is far lower than the annual 'safe' limit for healthcare workers of 20 mSv and is categorised as "Very Low Risk".

CONCLUSION

Clinicians involved in the treatment DDH can be re-assured that the cumulative radiation exposure from pelvic radiographs following Pavlik harness treatment is "Very Low Risk". Whilst being mindful of any radiation exposure in children, this study provides a scientific answer that help addresses parental concerns.

Predicting developmental dysplasia of the hip in at-risk newborns

Background

The development of developmental dysplasia of the hip can be attributed to several risk factors and often in combination with each other. When predicting the likelihood of developing this condition, clinicians tend to over and underestimate its likelihood of occurring.

Therefore, the study aim is to determine among at-risk newborns how to best predict developmental dysplasia of the hip (DDH) within 8 weeks post-partum.

Methods

Prospective cohort study in secondary care. Patient population included newborns at-risk for DDH – we assessed 13,276 consecutive newborns for the presence of DDH risk factors. Only newborns with at least one of the predefined risk factors and those showing an abnormal examination of the hip were enrolled (n = 2191). For the development of a risk prediction model we considered 9 candidate predictors and other variables readily available at childbirth.

The main outcome measure was ultrasonography at a median age of 8 weeks using consensus diagnostic criteria; outcome assessors were blinded.

Results

The risk model includes four predictors: female sex (OR = 5.6; 95% CI: 2.9–10.9; P <  0.001); first degree family history of DDH (OR = 4.5; 95% CI: 2.3–9.0; P <  0.001), birthweight > 4000 g (OR = 1.6; 95% CI: 0.6–4.2; P = 0.34), and abnormal examination of hip (OR = 58.8; 95% CI: 31.9, 108.5; P <  0.001). This model demonstrated excellent discrimination (C statistic = 0.9) and calibration of observed and predicted risk (P = 0.35). A model without the variable ‘hip examination’ demonstrated similar performance.

Conclusion

The risk model quantifies absolute risk of DDH within 8 weeks postpartum in at-risk newborns. Based on clinical variables readily available at the point of childbirth, the model will enhance parental counselling and could serve as the basis for real time decisions prior to discharge from maternity wards.

Developmental dysplasia of the hip

Developmental dysplasia of the hip encompasses a range of hip abnormalities in which the femoral head and acetabulum fail to develop and articulate anatomically. Developmental dysplasia of the hip is a clinically important condition, with a prevalence of 1-2/1000 in unscreened populations and 5-30/1000 in clinically screened populations. The pathology is incongruence between the femoral head and the acetabulum, which can be caused by an abnormally shaped femoral head, acetabulum, or both. This results in a spectrum of different hip abnormalities. The precise aetiology behind developmental dysplasia of the hip is unclear, but there are a number of established risk factors. In the UK, universal clinical examination of newborns and 6-8-week-old babies is performed under the national UK newborn screening programme for developmental dysplasia of the hip (part of the Newborn and Infant Physical Examination). The physical examination of the newborn hip involves initial inspection of the infant for any of the clinical features of developmental dysplasia of the hip, followed by hip stability tests (Barlow's and Ortolani's tests). Hip ultrasound is the gold standard diagnostic and monitoring tool for developmental dysplasia of the hip in newborns and infants under 6 months of age, or until ossification of the femoral head. Some mild cases of developmental dysplasia of the hip (and the immature hip) resolve without requiring intervention; however, there are a number of treatments, both non-operative and operative, that may be used at various stages of this condition.

Risk factors for failed closed reduction in dislocated developmental dysplastic hips

AIM OF THE STUDY

The present study aimed to identify risk factors for unsuccessful CR.

INTRODUCTION

Closed reduction (CR) represents the gold standard for treatment of developmental dysplasia of the hip (DDH), but to a minor percentage, it fails to reduce dysplastic hips successfully.

METHODS

Seventy-three dysplastic hips underwent closed reduction and post-interventional MRI of the pelvis. MRIs were evaluated for successful reduction of the hip, volumes of femoral heads, and acetabular diameter. Initial treatment results were correlated to AC angles at two years of follow-up. Contralateral, healthy hips served as control.

RESULTS

Out of 73 instable, dysplastic hips, there were nine cases of CR failure. These cases showed significantly increased femoral head volumes (p = 0.002) and a significantly (p = 0.02) larger ratio of femoral head volume to acetabular opening area. There was no significant difference (p = 0.15) in acetabular diameter between both groups. At two years of follow-up, AC angles were significantly (p = 0.003) larger and pathologic in cases of CR failure.

CONCLUSION

Exclusive enlargement of the femoral head is a risk factor for unsuccessful reduction and its ratio to the acetabular opening surface is predictive for CR success in DDH.

Genetic variant of COL11A2 gene is functionally associated with developmental dysplasia of the hip in Chinese Han population

OBJECTIVES

Developmental dysplasia of the hip (DDH) is a common skeletal disorder. This study was conducted to demonstrate the association between DDH and a polymorphism rs9277935 of COL11A2 gene.

RESULTS

A significant difference in genotype distribution in a recessive model (TT+GT vs. GG) between two groups (P=0.017) was demonstrated. Analysis in female patients showed significantly greater frequency of minor allele G(0.49 vs. 0.43, p=0.024) and significantly higher distribution of GG genotype (p=0.006). DDH patients were found to have significantly lower COL11A2 expression than controls. Moreover, DDH patients with rs9277935 genotype TT have a significantly increased expression of COL11A2 than those with genotype GG. COL11A2 demonstrated chondrogenic properties in vitro.

CONCLUSION

Polymorphism rs9277935 of gene COL11A2 is a functional variant regulating the expression and the chondrogenic properties of COL11A2 in DDH in Chinese Han population.

METHODS

A case-control candidate gene association study was conducted in 945 patients (350 radiologically confirmed DDH patients and 595 healthy controls). Difference of COL11A2 expression in hip joint tissue was compared between the patients and the controls. Allelic difference in Col11a2 expression by rs9277935 was assessed with luciferase activity. Chondrogenic effects of Col11a2 signaling on BMSCs were also determined in vitro.

Developmental dysplasia of the hip: real world data from a retrospective analysis to evaluate the effectiveness of universal screening

AIMS

Developmental dysplasia of the hip is an important cause of disability in children and young adult and it also has a significant socio-economic impact in our society. The main objective of our study is to evaluate, in our hospital, the effectiveness of a universal ultrasound screening protocol and to assess the general knowledge about the theme of pediatricians and neonatologists.

METHODS

Retrospective study of infants born from January 2016 to April 2019, evaluated with hip ultrasound (Graf method). Risk factors assessed were female gender, breech presentation at birth, positive family history and twin birth. For the secondary objective, an anonymous and validated questionnaire was distributed to all pediatricians and neonatologists.

RESULTS

Among the 4000 hips analyzed, on ultrasound examination, 98.8% hips resulted mature or immature but appropriate for age, while 1,2% hips were pathological. Analyzing the mature or immature hips, 2,4% were positive on clinical examination and 97,6% were negative. In relation to ultrasound pathological hips, 33,3% have positive clinical examination, while 66,7% negative. From the analysis of risk factors a significant association emerged between female sex, breech presentation and family history with the ultrasound pathological findings. The results of Survey showed that inadequate training about developmental dysplasia of the hip is done during medical school.

CONCLUSIONS

A universal ultrasound screening allowed us to identify developmental dysplasia of the hip in a number of children with normal clinical examination and no risk factors. Specific training courses should be implemented regarding Developmental Dysplasia of the Hip for neonatologists and pediatricians.

Risk factors during pregnancy and delivery for the development of Perthes' disease, a nationwide Swedish study of 2.1 million individuals

Background

To ascertain or disprove a correlation between suboptimal birth characteristics, breech position at delivery and development of Perthes’ disease.

Methods

Study material was collected from nationwide registers regarding diagnoses, birth statistics and delivery data. As study population were included children with a diagnosis code for Perthes’ disease who were alive and living in Sweden at age 13. Children with missing birth statistics were excluded. All children with no Perthes’ disease diagnosis were used as control group. Both single and multiple logistical regression analyses were used to calculate OR for the included characteristics.

Results

Children in breech position had a higher risk for developing Perthes’ disease. Children with Perthes’ disease had also a higher probability of having been born pre-term, very pre-term or post-term. Lower than normal birth weight and a lower Apgar-score were also associated with Perthes’ disease.

Conclusions

There is a correlation between breech birth and development of Perthes’ disease. There is also correlation to suboptimal birth characteristics. Despite our findings this should not be used for screening of Perthes’ disease as the percentage of children who actually develop it is very low. Also, as of yet there is no possibility to diagnose Perthes’ disease before the presence of skeletal changes. Our findings could be important in finding the cause of Perthes’ disease and therefore developing better diagnostics, treatment and prevention.

The association between periacetabular osteotomy reorientation and hip joint reaction forces in two subgroups of acetabular dysplasia

Acetabular dysplasia is primarily characterized by an altered acetabular geometry that results in deficient coverage of the femoral head, and is a known cause of hip osteoarthritis. Periacetabular osteotomy (PAO) is a surgical reorientation of the acetabulum to normalize coverage, yet its effect on joint loading is unknown. Our objective was to establish how PAO, simulated with a musculoskeletal model and probabilistic analysis, alters hip joint reaction forces (JRF) in two representative patients of two different acetabular dysplasia subgroups: anterolateral and posterolateral coverage deficiencies. PAO reorientation was simulated within the musculoskeletal model by adding three surgical degrees of freedom to the acetabulum relative to the pelvis (acetabular adduction, acetabular extension, medial translation of the hip joint center). Monte Carlo simulations were performed to generate 2000 unique PAO reorientations for each patient; from which 99% confidence bounds and sensitivity factors were calculated to assess the influence of input variability (PAO reorientation) on output (hip JRF) during gait. Our results indicate that reorientation of the acetabulum alters the lines of action of the hip musculature. Specifically, as the hip joint center was medialized, the moment arm of the hip abductor muscles was increased, which in turn increased the mechanical force-generating capacity of these muscles and decreased joint loading. Independent of subgroup, hip JRF was most sensitive to hip joint center medialization. Results from this study improve understanding of how PAO reorientation affects muscle function differently dependent upon acetabular dysplasia subgrouping and can be used to inform more targeted surgical interventions.

Associations between prenatal indicators of mechanical loading and proximal femur shape: findings from a population-based study in ALSPAC offspring

OBJECTIVES

Hip development is influenced by mechanical loading, but associations between prenatal loading and hip shape in later life remain unexplored.

METHODS

We examined associations between prenatal loading indicators (gestation length, oligohydramnios (OH) and breech) obtained from obstetric records and hip shape modes (HSMs) generated using dual-energy X-ray absorptiometry images taken at age 14- and 18-years in participants from the UK Avon Longitudinal Study of Parents and Children (ALSPAC). These associations were examined in 2453 (30 OH, 105 breech) and 2330 (27 OH, 95 breech) participants with complete data at age 14- and 18-years respectively using confounder-adjusted models.

RESULTS

At 14 years HSM2 was 0.59SD lower in OH males, and HSM5 (-0.31SD) and HSM9 (-0.32SD) were lower in OH in both sexes. At 18 years HSM1 (-0.44SD) and HSM2 (-0.71SD) were lower and HSM6 (0.61SD) and HSM8 (1.06SD) were higher in OH males, whilst HSM5 was lower in OH in both sexes. OH appeared to be associated with a wider femoral neck and head, and larger lesser/greater trochanters. Only weak associations were observed between gestation length/breech and HSMs.

CONCLUSIONS

These results suggest that prenatal skeletal loading, in particular oligohydramnios, may influence adolescent joint shape with associations generally stronger in males.

Plagiocephaly after Neonatal Developmental Dysplasia of the Hip at School Age

Developmental dysplasia of the hip (DDH) may require early abduction treatment with infants sleeping on their back for the first few months of life. As sleeping on back is known to cause deformational plagiocephaly, we assessed school age children treated for dislocation or subluxation of the hip-joint in infancy. Plagiocephaly was analyzed by using cephalic index (CI) and oblique cranial length ratio (OCLR) as anthropometric measurements from 2D digital vertex view photographs. Six of the 58 (10.3%) DDH children and only one of the 62 (1.6%) control children had plagiocephaly (p = 0.041). Furthermore, cross bite was found in 14 (24.1%) of the DDH children and in 7 (10.3%) of the control children. Developmental dysplasia of the hip in infancy was associated with cranial asymmetries and malocclusions at school age. Preventive measures should be implemented.

Incidence of Late-Diagnosed Hip Dislocation After Universal Clinical Screening in Sweden

IMPORTANCE

Developmental dysplasia of the hip, including late-diagnosed hip dislocation, is the leading cause of hip arthroplasties in young adults. Early treatment is essential for a good prognosis. Before the institution of a national screening program, a minimum of 0.9 per 1000 Swedish children were affected.

OBJECTIVES

To evaluate the incidence of late-diagnosed hip dislocation among children who undergo clinical screening as neonates and to study antenatal and perinatal risk factors for late-diagnosed hip dislocation.

DESIGN, SETTING, AND PARTICIPANTS

This nested case-control study included children born in Sweden from January 1, 2000, through December 31, 2009. All maternity wards, maternal health units, and orthopedic departments in Sweden participated. Children with a late-diagnosed hip dislocation were matched by sex and birth year to randomly selected controls in a 1:10 ratio. Potential risk factors in pregnant women and newborns were recorded, and cases of hip dislocation were registered. Observation time ranged from 8 to 18 years, with the last data analysis in January 2019.

EXPOSURES

Clinical hip examinations neonatally and at 6 to 8 weeks, 6 months, and 10 to 12 months.

MAIN OUTCOMES AND MEASURES

Hip dislocation diagnosed more than 14 days after birth, age at diagnosis, and severity of dislocation.

RESULTS

Among 1 013 589 live births (521 728 [51.5%] boys), 126 children (0.12 [95% CI, 0.10-0.15] per 1000 live births) had a late-diagnosed hip dislocation at a median age of 31.4 weeks (interquartile range, 16.1-67.1 weeks; 95% CI, 27.4-44.1 weeks). The incidence of late-diagnosed hip dislocation was 9 times higher among girls (113 of 491 861; 0.23 [95% CI, 0.19-0.28] per 1000 live births) than among boys (13 of 521 728; 0.02 [95% CI, 0.01-0.04] per 1000 live births). Twenty-one children (0.02 per 1000 live births) had high (severe) dislocations. Breech delivery (adjusted odds ratio, 3.07; 95% CI, 1.34-7.02), short body length at birth (adjusted odds ratio, 0.86; 95% CI, 0.76-0.98, per additional 1 cm), and being large for gestational age (adjusted odds ratio, 3.59; 95% CI, 1.30-9.95) were independent risk factors. Maternal smoking at the first visit to the maternal health care center was less common among children with hip dislocation (adjusted odds ratio, 0.16; 95% CI, 0.04-0.70).

CONCLUSIONS AND RELEVANCE

Compared with historical data, the incidence of late-diagnosed hip dislocation in Swedish-born children appears to have decreased substantially since the screening program was initiated, as have the age at detection and disease severity. Similar screening programs should also be possible to institute in upper-middle- and lower-middle-income countries.

Profile of Patients Diagnosed with Developmental Dysplasia of the Hip

Objective  To describe the profile of patients with developmental dysplasia of the hip (DDH) diagnosed by physical and ultrasound examination, with the implementation of a protocol for the treatment and follow-up of DDH.

Methods  A cross-sectional study with DDH patients born between January 2014 and December 2016, in the city of Pelotas, Southern Brazil. Ethnicity, gender, birth weight, fetal presentation, affected side of the hip, gestational age, maternal age and family history were considered. The data on the medical records were compared with the characteristics of the general population described on the Brazilian National Information System on Live Births (Sistema de Informação sobre Nascidos Vivos [SINASC]).

Results  A total of 33 DDH patients were identified, mostly female, with a four-fold higher probability of having the condition ( p  < 0.001); the left was the most affected side. No statistically significant association was found regarding the following factors: birth weight, gestational age, ethnicity, and maternal age. The newborns in breech presentation had a 15-fold higher probability of presenting DDH ( p  < 0.001). A total of 21 newborns required immediate treatment of the hips, since the ultrasound showed a Graf classification of IIb or higher, or the radiography showed dislocation in DDH patients older than 6 months of age.

Conclusion  Screening for DDH is essential in all newborns; physical examinations revealing alterations must be complemented with ultrasound imaging to avoid the delayed diagnosis of the condition.

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.

Oligohydramnios: should it be considered a risk factor for developmental dysplasia of the hip?

Breech, family history, first born and female sex are the main risk factors described for developmental dysplasia of the hip (DDH). Foot abnormalities and oligohydramnios have also been listed. Recent studies have discredited torticollis, multiple gestation pregnancy, mode of delivery and prematurity as risk factors. Definition of oligohydramnios in the literature is inconsistent. Our aim was to investigate the term oligohydramnios and evaluate whether it should be considered a risk factor for DDH. All live births in our institution between 2001 and 2014 were included. We identified all pregnancies classed as reduced amniotic fluid (AF) or oligohydramnios over that period. Data on DDH, breech presentation, female sex and positive family history were collected. The significance level was set to 5%. We identified 73 990 live births, 3408 pregnancies were classed as reduced AF or oligohydramnios. The incidence of DDH (Graf type IIb and higher) was 1: 1000 (75 babies, 18 bilateral). Oligohydramnios/reduced AF was found in 12 (16%) DDH babies. Breech presentation was found in 24 (32%), positive family history in 19 (25%) and female sex in 71 (94.7%). Oligohydramnios was found to be associated with a higher odds ratio (OR) for DDH [OR = 3.9, 95% confidence interval (CI): 2.1-7.3] as were breech presentation (OR = 10.6, 95% CI: 6.5-17.1) and female sex (OR = 19.1, 95% CI: 7-52.4). All examined risk factors showed statistical significance (P < 0.05). A regression analysis was performed to control for interactions and confounding factors and confirmed the findings. On the basis of our findings the diagnosis of reduced AF/oligohydramnios in consecutive antenatal sonographic scans should be regarded as an independent risk factor for DDH and be considered in any future studies regarding DDH. Level of evidence: Level IV: Case series.

Risk Factor Assessment and a Ten-Year Experience of DDH Screening in a Well-Child Population

Aim

Risk based screening for developmental dysplasia of the hip (DDH) with ultrasound is common. However, risk factors vary from one country to the other since data are insufficient to give clear recommendations. We aimed to evaluate the risk factors for developmental dysplasia of the hip (DDH).

Methods

In this retrospective case-control study, the health records of all children, who were followed up between 2004 and 2014 at a well-child unit, were investigated for the diagnosis of DDH in Turkey. Of 9758 children, 57 children were found to have abnormal ultrasonographic findings (according to Graf classification) and these constituted the case group. As the control group, healthy 228 children who matched the case children in birth months were selected. Two groups were compared for the risk factors.

Results

A total of 19516 hips of 9758 children were examined for DDH. 97 hips of 57 children were found to have abnormal ultrasonographic findings. When the two groups were compared, breech presentation, multiple pregnancy, and torticollis were identified as risk factors. The female sex was also found to have a significantly high prevalence among the children in the case group. Limited hip abduction, positive Ortolani, and Barlow signs were important clinical findings in the case group.

Conclusion

According to our findings, breech presentation, female sex, torticollis, and multiple pregnancy were found to be the risk factors of this disorder. Infants with these risk factors should be investigated carefully for DDH.