Developmental Dysplasia of the Hip: A Review of Etiopathogenesis, Risk Factors, and Genetic Aspects

Preliminary assessment of large language models' performance in answering questions on developmental dysplasia of the hip

Objective

To evaluate the performance of three large language models in answering questions regarding pediatric developmental dysplasia of the hip.

Methods

We formulated 18 open-ended clinical questions in both Chinese and English and established a gold standard set of answers to benchmark the responses of the large language models. These questions were presented to ChatGPT-4o, Gemini, and Claude 3.5 Sonnet. The responses were evaluated by two independent reviewers using a 5-point scale. The average score, rounded to the nearest whole number, was taken as the final score. A final score of 4 or 5 indicated an accurate response, whereas a final score of 1, 2, or 3 indicated an inaccurate response.

Results

The raters demonstrated a high level of agreement in scoring the answers, with weighted Kappa coefficients of 0.865 for Chinese responses (p < 0.001) and 0.875 for English responses (p < 0.001). No significant differences were observed among the three large language models in terms of accuracy when answering questions, with rates of 83.3%, 77.8%, and 77.8% for Claude 3.5 Sonnet, ChatGPT-4o, and Gemini in the Chinese responses (p = 1), and 83.3%, 83.3%, and 72.2% for ChatGPT-4o, Claude 3.5 Sonnet, and Gemini in the English responses (p = 0.761). In addition, there was no significant difference in the performance of the same large language model between the Chinese and English settings.

Conclusions

Large language models demonstrate high accuracy in delivering information on dysplasia of the hip, maintaining consistent performance across both Chinese and English, which suggests their potential utility as medical support tools.

Level of evidence

Level II.

Evaluating the Short-Term Impact of Closed Versus Open Reduction Techniques on Acetabular Remodeling in Developmental Hip Dysplasia

INTRODUCTION

Developmental dysplasia of the hip (DDH) encompasses abnormalities in the acetabulum or the femoral head, ranging from mild dysplasia to complete dislocation. The primary goal of DDH treatment is to achieve and maintain a concentric reduction of the hip joint, allowing for normal acetabular and femoral head remodeling.

METHOD

This retrospective study reviewed records of patients treated for idiopathic DDH between 2016 and 2021 at a single institution. Patients included had undergone either closed or open reduction and completed at least two years of follow-up. Demographic data and radiographic assessments at multiple intervals postreduction were collected and analyzed using IBM SPSS Statistics for Windows, Version 29 (Released 2023; IBM Corp., Armonk, New York, United States).

RESULTS

A total of 41 patients (64 hips) were included, with a mean age at reduction of 6.92 months and a follow-up duration of 51.5 months. Closed reduction was performed on 38 hips, while 26 hips underwent open reduction. The mean age at reduction was significantly lower in the closed reduction group (4.58 months) compared to the open reduction group (10.34 months). The mean preoperative acetabular index (AI) decreased from 37.39 to 19.54 in the closed reduction group and from 36.74 to 19.4 in the open reduction group.

CONCLUSION

The study found no significant difference between closed and open reduction techniques in acetabular remodeling. While residual dysplasia and avascular necrosis (AVN) were more common in the closed group, the differences were not statistically significant. Further research with larger sample sizes and longer follow-up periods is recommended to confirm these findings.

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.

Robotically Assisted vs. Manual Total Hip Arthroplasty in Developmental Hip Dysplasia: A Comparative Analysis of Radiological and Functional Outcomes

Background/Objectives: Developmental dysplasia of the hip (DDH), defined by the malalignment of the femoral head and acetabulum, is a major precursor to coxarthrosis, posing substantial challenges during total hip arthroplasty (THA). Patients with coxarthrosis secondary to DDH often exhibit acetabular bone insufficiency, which makes challenging surgical reconstruction difficult. This study aimed to compare the radiologic and functional outcomes of robotically assisted and conventional manual THA techniques in patients with coxarthrosis secondary to Crowe type III-IV DDH. Methods: This prospective study included 40 patients divided into robotically assisted (n = 20) and conventional manual (n = 20) THA groups. Evaluations encompassed hip pain (Visual Analogue Scale, VAS), function (Harris hip score and University of California, Los Angeles, activity scale), quality of life (Short Form-12), and prosthesis sensation (Forgotten Joint Score-12). Radiologic outcomes included acetabular inclination and anteversion angles. Femoral shortening, operative duration, and follow-up times were also analyzed. Results: Demographic characteristics did not differ between groups (p > 0.05). Robotically assisted THA exhibited a significantly longer operative time (171.40 ± 11.96 vs. 150.30 ± 14.67 min; p = 0.001) but a shorter follow-up (29.3 ± 8.51 vs. 52.95 ± 18.96 months; p = 0.001), without a difference in the amount of femoral shortening (p = 0.947). Despite the extended surgical duration, the two techniques achieved comparable radiologic outcomes, with no significant differences in acetabular inclination or anteversion angles (p > 0.05). Functional assessments, including Harris hip scores (73.85 vs. 73.95; p = 0.978), UCLA activity scores, and VAS, indicated similar efficacy between groups. SF-12 physical and mental quality of life and Forgotten Joint Score-12 prosthesis sensation did not differ between groups (p > 0.05). Conclusions: This study concludes that robotically assisted and conventional manual THA present similar radiologic and functional outcomes in patients with coxarthrosis secondary to Crowe type III-IV DDH, as displayed by comparable acetabular anteversion and inclination alignment, femoral shortening, hip function, pain, quality of life, and prosthesis sensation scores. While robotically assisted THA requires a longer operative time, its precision in implant placement may hold potential advantages for long-term outcomes, demanding further investigation in extended follow-up studies.

Association of hip dysplasia in newborns with ethnicity using graf method ultrasound

Objectives

To determine gender and ethnic distribution of developmental dysplasia of hip in newborns using Graf method for ultrasound. To determine the significance of association between developmental dysplasia of hip with ethnicity in newborns using Graf's method ultrasound.

Method

This analytical cross-sectional observational study was conducted in Karachi from January through June 2022 .A total of 115 healthy newborns (both male and female) aged under 28 days were included in the study after parental informed consent. Hip dislocation was assessed clinically using Barlow and Ortolani maneuvers. The gender, ethnicity and hip angles were recorded in the proforma. Graf's method ultrasound was used to measure the hip angles. Acetabular roof, head of femur, triradiate cartilage and acetabular labrum were used as landmarks for angle measurements. The hip joint was classified based on Graf method criteria.

Results

The incidence of hip dysplasia was higher in male (16.08%) as compared to female infants (14.78%). The difference between gender distributions was not significant. The predominant ethnicities with pathological hip were Sindhi (9.13%), Punjabi (7.39%) and Pathan (6.08%). The association between ethnicity and pathological hips was statistically significant (p=0.021).

Conclusion

There is no significant difference in incidence of DDH with gender. However, there is a significant association between ethnicity and incidence of developmental dysplasia of hip in neonates of 28 days age. Incidence of DDH is high in the Sindhi, Punjabi and Pathan populations.

Early Outcomes of Arthroscopic Versus Open Reduction for Developmental Dysplasia of the Hip in Children: A Randomized Controlled Trial

AIM

This study aims to assess and compare the early outcomes of arthroscopic-assisted reduction with open reduction techniques in the surgical treatment of developmental dysplasia of the hip (DDH) in children. The trial was conducted in two tertiary care hospitals specializing in pediatric orthopedic surgery in Erbil, Iraq.

MATERIALS AND METHODS

This parallel-group, randomized controlled trial (RCT) included a total of 43 children aged 12-24 months with DDH (Tönnis grade II or higher) who were randomly allocated into two groups: arthroscopic-assisted reduction (n = 19) and open surgical reduction (n = 24). Exclusion criteria included neuromuscular disorders, teratologic hip dislocations, and previous hip surgery. The patients were treated by either arthroscopic-assisted or open reduction according to the randomization. The postoperative treatment was the same for all groups, comprising hip spica casting. The study's main outcome measures were clinically and radiographically documented redislocation rates at 6, 12, and 24 months postoperatively, operative time, estimated blood loss, radiographic measurements of the acetabular index, and complications such as avascular necrosis (AVN).

RESULTS

Redislocation rates were significantly lower in the arthroscopic-assisted reduction group (0%) compared to that of the open surgical reduction group (44%) (p = 0.047). The arthroscopic-assisted reduction resulted in shorter operative times (mean 94.3 minutes) and lower estimated blood loss (mean 141.9 mL) compared to open reduction techniques (p < 0.001). No significant differences were observed in the acetabular index across groups at six months, one year, or two years postoperatively (p > 0.05). AVN rates were highest in the open surgical reduction group (44%) compared to the arthroscopic group (21%), but this difference was not statistically significant (p = 0.074).

CONCLUSION

Arthroscopic-assisted reduction demonstrated superior short-term outcomes in terms of redislocation rates, operation time, and blood loss compared with open surgical techniques. Although the rates of AVN did not reach statistical significance, the possibility of preserving vascularity in arthroscopic procedures is promising for reducing long-term complications. Longer follow-up and further multicenter trials are required to confirm these findings.

Predictors of treatment duration in conservative management of developmental dysplasia of hip -a retrospective cohort study

Developmental dysplasia of the hip is a prevalent condition in newborns. However, predicting the duration of conservative treatment remains challenging. This study aimed to determine the duration of treatment more precisely by analyzing associated factors. We conducted a retrospective analysis and developed a linear regression model based on 503 patients treated at our institution over the last 10 years. A linear regression model (GLM) was used for predicting treatment duration (df residuals 371, df model 3, Pearson Chi2 78.9, Number of iterations 15). The baseline scenario thereby feature a child with an average age at the beginning of treatment (35th day of life), both sides pathologically affected, and a minimum alpha angle of 29 degrees. The GLM identified age at treatment onset, alpha angle, and bilaterality as significant predictors of treatment duration. A four-week delay in treatment initiation extended the duration by one week, while a 5-degree increase in the alpha angle reduced it by two weeks. Bilaterality added 19 days to treatment duration. However, sex and clinical hip instability did not significantly affect the treatment time. These findings enable the calculation of treatment duration based on identified factors, potentially improving the management and planning of conservative therapies for developmental dysplasia of the hip in newborns.

Postural Abnormalities in Children with Congenital Zika Syndrome-Related Neurological and Visual Impairment

Deformities, body asymmetries, and muscle contractures are common consequences of atypical postural patterns in children with c ongenital Zika syndrome (CZS). This study aimed to evaluate the posture of children with CZS, considering their neurological and visual impairments. Ophthalmological assessment included binocular best-corrected visual acuity (BCVA) using Teller Acuity Cards II (TAC II) and an ocular motility evaluation. Postural alignment was measured using the PhysioCode Posture (PCP) app. Twenty-four children with CZS (12 [50.0%] female) were included, with a mean age of 6.8 ± 0.7 years (range, 4.0-7.0 years). The majority (79.2% [19/24]) had microcephaly at birth. Visual impairment was detected in 95.2% (20/21) of the children, with 85.0% (17/20) classified as moderate, severe, or blind. Shoulder asymmetry was observed in 95.8% (23/24) of participants, and 75.0% (18/24) presented abnormal postural alignment of the head and hips. Additionally, spinal deviations were found in 41.7% (10/24) of the children. All children with CZS exhibited asymmetries and improper postural patterns, which may result from a combination of neurological and visual impairments as well as environmental factors.

Total hip arthroplasty preoperative planning for childhood hip disorders' sequelae: Focus on developmental dysplasia of the hip

Developmental dysplasia of the hip (DDH) poses significant challenges in both childhood and adulthood, affecting up to 10 per 1000 live births in the United Kingdom and United States. While newborn screening aims to detect DDH early, missed diagnoses can lead to severe complications such as hip dysplasia and early onset osteoarthritis in adults. Treatment options range from less invasive procedures like hip-preserving surgery to more extensive interventions such as total hip arthroplasty (THA), depending on the severity of the condition. Preoperative planning plays a critical role in optimizing surgical outcomes for DDH patients undergoing THA. This includes accurate imaging modalities, precise measurement of acetabular bone stock, assessment of femoral head subluxation, and predicting prosthesis size and leg length discrepancy. Recent advancements artificial intelligence and machine learning offer promising tools to enhance preoperative planning accuracy. However, challenges remain in validating these technologies and integrating them into clinical practice. This editorial highlights the importance of ongoing research to refine preoperative strategies and improve outcomes in DDH management through evidence-based approaches and technological innovations.

Clinical Evaluation of an Electronic Guidance System for Optimizing the Ultrasound Screening for Developmental Hip Dysplasia in Newborns

Background: Graf ultrasound screening is considered an established method for early detection of developmental dysplasia of the hip (DDH). Although characterized by a high degree of standardization to allow for good reproducibility of results, examination-related factors may still affect sonographic measurements. The relative tilt angle between the hip and the probe is a potential pitfall as it significantly influences sonographic measurements and consequently classification of DDH according to Graf. Objectives: Evaluation of an electronic guidance system developed to reduce relative tilt angles and increase reliability and comparability in ultrasound screening of DDH. Materials and Methods: Twenty-five newborns were examined using a prototype guidance system, which tracks the position of the transducer and the pelvis to calculate the relative tilt angles. Two ultrasound images were obtained, one conventionally and the other one using the guidance system. Subsequently, relative roll and pitch angles and sonographic measurements were determined and analyzed. Results: The relative inclination angles in the conventional group ranged from -12.6° to 14.3° (frontal plane) and -23.8° to 32.5° (axial plane). vs. -3.7° to 3.0° and -3.2° to 4.5° in the guidance system group. The variances were significantly lower in the guidance system-assisted group for both planes (p < 0.001 and p < 0.001, respectively). The optimized transducer position showed significant effects and consequently significantly reduced alpha angles were observed (p = 0.001, and p = 0.003). Conclusions: The guidance system allowed a significant reduction in the relative tilt angles, supporting optimal positioning of the transducer, resulting in significant effects on Graf sonographic measurements. This technique shows great potential for enhancing the reproducibility and reliability of ultrasound screening for DDH.

Risk Factors for Developmental Dysplasia of the Hip: A Critical Analysis About an Unclear Relationship

Objective: To evaluate the relationship between prenatal risk factors and developmental dysplasia of the hip using the Graf grade, and to identify the determinants of a higher Graf grade. Materials and Methods: A retrospective analysis of data from 112 newborns with DDH was conducted. The participants were selected on the basis of a DDH diagnosis using sonography. A total of 181 hips of patients with DDH were considered in our study group (Graf types IIa to IV), and the normal hips of those affected unilaterally were excluded from the analyses (43 participants were affected unilaterally). The risk factors considered included female sex, breech presentation, firstborn status, familiarity, association with other orthopedic abnormalities, and uterine packing, which includes factors such as twin pregnancy, macrosomia, and oligohydramnios. Binary logistic regression was used to analyze the relationship between these variables and the Graf type of DDH at presentation, which was defined using two groups: Graf types IIc-IV, which include unstable or decentered hips, and Graf types IIa and IIb, which encompass stable and centered hips. Results: The analyses revealed a significant protective role of the presence of other lower limb congenital malformations such as clubfoot, which was more closely associated with a stable form of DDH (OR = 0.26, p = 0.017), a significant association between the presence of mechanical risk factors in females with an unstable form of DDH (OR = 5.00, p = 0.042), a borderline significant protective role of breech presentation in females, which was more closely associated with a stable form of DDH (OR = 0.25, p = 0.054), and a borderline significant association between the presence of mechanical risk factors and an unstable form of DDH (OR = 4.28, p = 0.054). Conclusions: Prenatal risk factors may have a complex effect on the Graf grade in DDH. The protective effects of some factors in contrast with the increased risk associated with other factors suggest a possible relationship, with some prenatal risk factors affecting the severity of DDH. These findings may have implications for the early identification and management of DDH.

Maternal perceptions and awareness regarding developmental dysplasia of the hip in children among mothers and pregnant women in Makkah City, Saudi Arabia

Background

Developmental dysplasia of the hip (DDH) is a spectrum of disorders that develop in utero, involving the femoral head and acetabular cup development, ranging from dysplasia to dislocation. The prevalence of DDH in Saudi Arabia is 10.46 per 1000 live births. However, the late presentation of DDH in Saudi Arabia is around 30%, believed to be significantly due to a lack of awareness of the disease among mothers and pregnant women.

Aims

This study aimed to measure maternal perceptions and awareness regarding DDH in children among mothers and pregnant women in Makkah City, Saudi Arabia.

Method

In total, 406 women participated in an electronic survey. The survey questions were adapted from previously published research, and the questionnaire was available in Arabic.

Results

The age distribution of the participants ranged from below 20 to over 50 years, with the largest group being 31-40 years old. Most of the participants had a university-level education (61.1%). The overall assessment showed a predominance of poor knowledge (41.1%), followed by good knowledge (34.7%), and then medium knowledge (24.1%).

Conclusion

The present study revealed significant knowledge gaps and barriers to the early detection and intervention of DDH among Makkah City mothers and pregnant women. The findings underscore the need for targeted educational campaigns, increased access to screening programs, and heightened healthcare provider knowledge to improve DDH's perception and awareness. Future interventions should focus on addressing these gaps and promoting early detection and intervention strategies to minimize the long-term consequences of DDH.

Two genetic variants in the HIBCH and FTCDNL1 genes are associated with susceptibility to developmental dysplasia of the hips among the Han Chinese population of Southwest China

BACKGROUND

Developmental dysplasia of the hip (DDH) is a common cause of childhood disability, and the incidence of DDH shows significant familial aggregation. As the genetic factors of DDH remain unknown, the correlation between five candidate single nucleotide polymorphisms (SNPs) and DDH was evaluated in the Han Chinese population of Southwest China.

METHODS

A case‒control association study was conducted in 276 patients with DDH and 318 healthy controls. SNP genotyping in the case and control groups was performed by SNPshot and multiple PCR. SNPs were genotyped in the case and control groups by multiplex PCR. The relationship between DDH and candidate SNPs was evaluated using the χ2 test.

RESULTS

The genotype distributions of rs291412 in HIBCH and rs769956 in FTCDNL1 were different between the case and control groups (P < 0.05). After genetic model analysis, logistic regression analysis revealed that the C allele of rs291412 had a protective effect on DDH (OR = 0.605, P = 0.010) and that the G allele of rs769956 was a risk factor (OR = 2.939, P = 0.010).s.

CONCLUSION

These SNPs could be associated with susceptibility to DDH but larger population-based studies should confirm the current results.

Molecular mechanisms and genetic factors contributing to the developmental dysplasia of the hip

The most prevalent hip disease in neonates is developmental dysplasia of the hip (DDH). A timely and accurate diagnosis is required to provide the most effective treatment for pediatric patients with DDH. Heredity and gene variation have been the subject of increased attention and research worldwide as one of the factors contributing to the pathogenesis of DDH. Genome-wide association studies (GWAS), genome-wide linkage analyses (GWLA), and exome sequencing (ES) have identified variants in numerous genes and single-nucleotide polymorphisms (SNPs) as being associated with susceptibility to DDH in sporadic and DDH family patients. Furthermore, the DDH phenotype can be observed in animal models that exhibit susceptibility genes or loci, including variants in CX3CR1, KANSL1, and GDF5. The dentification of noncoding RNAs and de novo gene variants in patients with DDH-related syndrome has enhanced our understanding of the genes implicated in DDH. This article reviews the most recent molecular mechanisms and genetic factors that contribute to DDH.

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.

Deciphering the pathogenic role of rare RAF1 heterozygous missense mutation in the late-presenting DDH

Background

Developmental Dysplasia of the Hip (DDH) is a skeletal disorder where late-presenting forms often escape early diagnosis, leading to limb and pain in adults. The genetic basis of DDH is not fully understood despite known genetic predispositions.

Methods

We employed Whole Genome Sequencing (WGS) to explore the genetic factors in late-presenting DDH in two unrelated families, supported by phenotypic analyses and in vitro validation.

Results

In both cases, a novel de novo heterozygous missense mutation in RAF1 (c.193A>G [p.Lys65Glu]) was identified. This mutation impacted RAF1 protein structure and function, altering downstream signaling in the Ras/ERK pathway, as demonstrated by bioinformatics, molecular dynamics simulations, and in vitro validations.

Conclusion

This study contributes to our understanding of the genetic factors involved in DDH by identifying a novel mutation in RAF1. The identification of the RAF1 mutation suggests a possible involvement of the Ras/ERK pathway in the pathogenesis of late-presenting DDH, indicating its potential role in skeletal development.

Treatment of developmental hip dysplasia with manual therapy following Pavlik harness failure: a case report with long-term follow-up

BACKGROUND

Developmental dysplasia of the hip (DDH) is a common musculoskeletal disorder in newborns, ranging from mild dysplasia to complete dislocation. Early detection and intervention are crucial for managing DDH. However, in some cases, standard orthopedic treatments such as the Pavlik harness fail, and alternative approaches are needed. Our study explores the possibility that manual therapy, specifically the Mézières-Bertelè Method (MBM), could be beneficial in cases of DDH that are resistant to conventional treatments.

CASE DESCRIPTION

We present a case of a 20-month-old female who had been suffering from persistent DDH (Graf's type IIIC on the left), pain and limping, despite previous conventional treatments, including the Pavlik harness. The patient received daily MBM sessions for six months, followed by maintenance sessions every two months.

OUTCOMES

After undergoing the MBM treatment, the patient showed clinical improvements, such as normal neuromotor development and restored hip joint parameters. We observed normal walking and running abilities, and X-ray parameters returned to normal levels. The patient sustained positive outcomes during long-term follow-up until the age of 7.

CONCLUSION

The MBM manual therapy was used to treat a challenging case of DDH resistant to conventional treatment. This case report suggests a possible correlation between manual therapy and improved outcomes in resistant DDH and highlights the potential relevance of addressing the inherent musculoskeletal components of the condition.

Impact of endoplasmic reticulum stress on chondrocyte apoptosis in rat model of DDH

Developmental dysplasia of the hip (DDH) is a developmental disorder characterized by acetabular dysplasia leading to early osteoarthritis. This study examines the role of endoplasmic reticulum stress (ERS) in chondrocyte apoptosis and cartilage degeneration within a DDH model. In the rat model of DDH, created using a swaddling technique, significant deformities in the femoral head and acetabulum were observed, alongside an upregulation of matrix metalloproteinase-13 in acetabular cartilage. We also noted increased levels of apoptosis and ERS-related factors in the acetabular cartilage of DDH models. Additionally, rat chondrocytes exposed to high-magnitude cyclic tensile strain (CTS, 1 Hz, 10% equibiaxial strain) in vitro exhibited elevated ERS and increased apoptosis. Importantly, treatment with the ERS inhibitor 4-phenylbutyric acid effectively suppressed apoptosis induced by CTS in chondrocytes. Our findings suggest that ERS contributes to the upregulation of apoptosis-related factors in chondrocytes within the DDH model, indicating the potential of ERS modulation as a therapeutic approach for DDH-related cartilage degeneration.

Environmental and Genetic Risk Factors in Developmental Dysplasia of the Hip for Early Detection of the Affected Population

Diagnosis of developmental dysplasia of the hip (DDH) mostly relies on physical examination and ultrasound, and both methods are operator-dependent. Late detection can lead to complications in young adults. Current evidence supports the involvement of environmental and genetic factors, such as single nucleotide variants (SNVs). Incorporating genetic factors into diagnostic methods would be useful for implementing early detection and management of affected individuals. Our aim was to analyze environmental factors and SNVs in DDH patients. We included 287 DDH cases and 284 controls. Logistic regression demonstrated an association for sex (OR 9.85, 95% CI 5.55-17.46, p = 0.0001), family history (OR 2.4, 95% CI 1.2-4.5, p = 0.006), fetal presentation (OR 3.19, 95% CI 1.55-6.54, p = 0.002), and oligohydramnios (OR 2.74, 95%CI 1.12-6.70, p = 0.026). A model predicting the risk of DDH including these variables showed sensitivity, specificity, PPV, and NPV of 0.91, 0.53, 0.74, and 0.80 respectively. The SNV rs1800470 in TGFB1 showed an association when adjusted for covariables, OR 0.49 (95% CI 0.27-0.90), p = 0.02. When rs1800470 was included in the equation, sensitivity, specificity, PPV and NPV were 0.90, 0.61, 0.84, and 0.73, respectively. Incorporating no-operator dependent variables and SNVs in detection methods could be useful for establishing uniform clinical guidelines and optimizing health resources.

Incidence of Nerve Palsies During Pavlik Harness Treatment for Developmental Dysplasia of the Hip: A Retrospective Cohort Study

BACKGROUND

The Pavlik harness has been used for approximately a century to treat developmental dysplasia of the hip (DDH). Femoral nerve palsy is a documented complication of Pavlik harness use, with an incidence ranging from 2.5% to 11.2%. Rare reports of brachial plexus palsy have also been documented. The primary purpose of the current study was to evaluate the incidence of various nerve palsies in patients undergoing Pavlik harness treatment for DDH. Secondary aims were to identify patient demographic or hip characteristics associated with nerve palsy.

METHODS

We performed a retrospective review of patients diagnosed with DDH and treated with a Pavlik harness from February 1, 2016, to April 1, 2023, at a single tertiary care orthopaedic hospital. Hip laterality, use of a subsequent rigid abduction orthosis, birth order, breech positioning, weight, and family history were collected. The median (and interquartile range [IQR]) or mean (and standard deviation [SD]) were reported for all continuous variables. Independent 2-sample t tests and Mann-Whitney U tests were conducted to identify associations between the variables collected at the initiation of Pavlik harness treatment and the occurrence of nerve palsy.

RESULTS

Three hundred and fifty-one patients (547 hips) were included. Twenty-two cases of femoral nerve palsy (4% of all treated hips), 1 case of inferior gluteal nerve palsy (0.18%), and 2 cases of brachial plexus palsy (0.37%) were diagnosed. Patients with nerve palsy had more severe DDH as measured by the Graf classification (p < 0.001) and more severe DDH as measured on physical examination via the Barlow and Ortolani maneuvers (p = 0.003).

CONCLUSIONS

Nerve palsies were associated with more severe DDH at the initiation of Pavlik harness use. Upper and lower-extremity neurological status should be scrutinized at initiation and throughout treatment to assess for nerve palsies. The potential for femoral, gluteal, and brachial plexus palsies should be included in the discussion of risks at the beginning of treatment. Families may be reassured that nerve palsies associated with Pavlik harness can be expected to resolve with a short break from treatment.

LEVEL OF EVIDENCE

Therapeutic Level III. See Instructions for Authors for a complete description of levels of evidence.

Bilateral Involvement in Developmental Dislocation of the Hip: Analysis of 561 Patients Operated on Using the Limited Posteromedial Approach

Our objective was to scrutinize the risk factors related to bilateral involvement in the developmental dysplasia of the hip (DDH) and to inspect the impact of bilaterality on the enduring results of the DDH. All patients, aged between 6 and 18 months, who underwent surgery using the limited posteromedial approach (734 hips from 561 patients), were included in this study. The number of births, birth type, history of consanguineous marriage, family history, and swaddling were analyzed. Physical examination and complaints of the patients were evaluated, and direct radiographs were examined in terms of the redislocation, avascular necrosis, and residual acetabular dysplasia. Among the 561 patients, bilateral DDH was observed in 173 patients (30.8%). The use of swaddling was found to be statistically significant between groups (p = 0.012). The use of swaddling for more than one month was associated with a higher odds ratio for bilaterality (p = 0.001, OR = 1.56, 95% CI: 1.2-2.0). Furthermore, bilaterality was associated with a higher risk for redislocation in DDH (p = 0.001, OR = 4.25, 95% CI: 1.6-11.2). The study concludes that swaddling for over a month is strongly linked with the bilateral involvement in DDH. It is important to note that bilaterality plays a crucial role in the development of redislocation after open reduction in DDH.

Clinical significance of polymorphisms of genes encoding collagen (COL1A1, COL5A1) and their correlation with joint laxity and recurrent patellar dislocation in adolescents

The aim of this study was to assess the coexistence of polymorphisms of the COL1A1 and COL5A1 genes with clinically diagnosed laxity and the occurrence of recurrent patellar dislocation in adolescents. The research group comprised 50 cases of recurrent patellar dislocation. The mean age at diagnosis was 14.2 years (10-17, SD 2.6). The control group consisted of 199 participants without a diagnosis of recurrent patellar dislocation, with a mean age of 15.2 (10-17 years, SD 2.7). Joint laxity by the Beighton scale was assessed. Analysis of the allele distribution of the analysed genes COL1A1 and COL5A1 revealed no statistically significant difference between the study group and the control group (p = 0.859 and p = 0.205, respectively). Analysis of the Beighton score showed a statistically significantly higher result in the study group than in the control group (p < 0.001). No correlation between the presence of polymorphisms and joint laxity diagnosis was confirmed. In conclusion, COL1A1 and COL5A1 gene polymorphisms are not significantly more common in adolescents with recurrent patellar dislocation than in healthy peers; there is also no correlation between joint laxity and polymorphisms of the COL1A1 and COL5A1 genes.Registered on ClinicalTrials.gov with ID: PMMHRI-2021.2/1/7-GW.

Effect of hip dysplasia on the development of the femoral head growth plate

Purpose

The purpose of this study was to observe whether developmental dysplasia of the hip (DDH) affects the development of the femoral head growth plate and to analyze the risk factors.

Methods

We selected female patients aged between 11 and 20 years with unilateral DDH and unclosed femoral head growth plate (s). The selected patients underwent anteroposterior radiography of the hip joint to compare the degree of development of the femoral head growth plate on both sides and to identify risk factors that affect the development of the growth plate in the femoral head.

Results

We included 48 female patients with unilateral DDH, with an average age of 14 years (range: 11.1-18.5 years) and an average BMI of 20.4 kg/m² (range: 15.5 kg/m²-27.9 kg/m²). Among them, 23 patients had earlier development of the femoral head growth plate on the affected side than on the healthy side, while the degree of development of the femoral head growth plate in 25 patients was the same as that on the contralateral side. When the Tönnis angle was greater than 29.5°C and/or the Reimers migration index was greater than 48.5%, there was a statistically significant difference in the acceleration of femoral head growth plate development.

Conclusion

An abnormal relative position of the acetabulum-femoral head caused by DDH can accelerate closure of the femoral head growth plate in immature female patients. The risk factors are a Tönnis angle greater than 29.5°C and/or Reimers migration index greater than 48.5%.

Prevalence of developmental dysplasia of the hip (DDH) in infants: a systematic review and meta-analysis

OBJECTIVE

To estimate the prevalence of developmental dysplasia of the hip (DDH) in infants with a systematic review and meta-analysis.

METHOD

A literature search was conducted in April 2023, using databases such as Cochrane Library, PubMed, MEDLINE, CNKI, and SinoMed, without language restrictions. Eligible studies included cross-sectional studies reporting the prevalence of DDH among infants aged 0-12 months. Two independent reviewers manually selected and coded the studies, with any disagreements resolved by a third reviewer. Meta-analysis was performed using a random-effects model to calculate the prevalence of DDH. Regression analysis examined the trend of DDH prevalence, and stratification analysis explored heterogeneity between studies.

RESULTS

A total of 65 studies involving 3 451 682 infants were included in the meta-analysis. None of the studies were classified as high quality, four were medium-to-high quality, 50 were low-to-medium quality, and eight were low quality. The pooled prevalence of DDH was 1.40% (95% CI: 0.86 to 2.28, I2=100%), and prevalence of dysplasia, subluxation, and dislocation was 1.45% (95% CI: 0.93 to 2.24, I2=97%), 0.37% (95% CI: 0.22 to 0.60, I2=94%), and 0.21% (95% CI: 0.13 to 0.34, I2=92%), respectively. Notably, the overall prevalence has a slight upward trend in the last three decades (β=0.24, p=0.35), but the dysplasia was downward trend (β=-0.48, p<0.01). Girls have higher risk of DDH than boys (1.46% vs 0.66%; Q=5.83, df=1, p=0.02). There were no significant differences based on gender, country, setting, or screening technique.

CONCLUSION

The prevalence of DDH among infants is approximately one in a 100, with girls being at higher risk. Though the prevalence of dysplasia has decreased, there is a slight upward trend in overall DDH. Therefore, routine screening for DDH in infants is recommended to prevent more serious developmental problems.

Patients with developmental dysplasia of the hip shows higher digit ratio (2D:4D)

BACKGROUND

Developmental dysplasia of the hip (DDH) encompasses a range of hip disorders, from dysplasia to dislocation. One key factor is sex, with women being four to eight times more susceptible to DDH than men. However, there have been no studies investigating the second-to-fourth digit ratio (2D:4D), a biomarker of prenatal sex steroid exposure, in DDH patients. This study aimed to explore whether there is an association between the 2D:4D ratio and DDH.

METHODS

Digital calipers were used to measure the second and fourth finger lengths of 250 patients treated for DDH and 200 patients in the healthy control group between January 2020 and January 2023. The Mann-Whitney U test was used for non-normally distributed variables and two-way analysis of variance to assess differences in measurements between DDH patients based on sex, side, and the interaction of sex and side. The intraclass correlation coefficient (ICC) was used to assess measurement repeatability.

RESULTS

The median (min-max) age was 10.00 (6-16) years in the DDH group, 12.00 (6-16) years in the control group, and 10 (6-16) years for the whole cohort. There was no significant difference in terms of age between the patient and control groups (p = 0.083). When comparing the DDH group with controls the former showed higher right 2D:4D and Δ2D:4D and these differences were significant in both males and females. Among the patients, controlling for side of dysplasia did not affect right 2D:4D, left 2D:4D or Δ2D:4D.

CONCLUSION

There was a significant association between higher 2D:4D ratios (both right and left hands) and DDH in both men and women. This indicates that the 2D:4D ratio, a marker of intrauterine estrogen/testosterone balance, is associated with DDH.

Identification of A Novel Variant of Filamin A Destroying the Attraction Between Benzene Rings and Sulfhydryl in Developmental Dysplasia of the Hip

Developmental dysplasia of the hip (DDH), characterized by acetabular deformity that manifests from loose ligaments to complete dislocation of the hip, can cause notable pain and dysfunction and lead to hip dislocation, secondary fractures, scoliosis, and osteoarthritis of hip. Variants in FLNA may produce a spectrum of malformations in multiple organs, especially the skeleton. This study aimed to identify the genetic etiologies of DDH patients and provide genetic testing information for further diagnosis and treatment of DDH. We recruited a Chinese woman with DDH and her family members. Whole-exome sequencing was used to identify the patient's genetic etiologies. Protein models were used to analyze the pathogenic mechanism of the identified variants. A novel variant (c.3493T>G, p.C1165G) of FLNA was detected. The structural models of the mutant FLNA protein indicated that the variant would lose its sulfhydryl side chain and destroy the attraction between benzene rings and sulfhydryl. We reported a novel variant (c.3493T>G, p.C1165G) of FLNA in a Chinese woman with DDH. Our research outcome enriches the gene pool for hip dysplasia and emphasizes the pathogenicity of sulfhydryl side chain disruption in FLNA.

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.

Prevalence of Breech Presentation and Other Gestational/Delivery Characteristics Among Patients Born With Developmental Dysplasia of the Hip

Introduction Developmental dysplasia of the hip (DDH) is the most common congenital disability in newborns. The condition can range from a slight laxity in the hip joint to secondary femoral head injury, early osteoarthritis (OA), and mobility issues. There are several risk factors for DDH, including positive family history, female sex, breech presentation, and the presence of clubfoot. Early detection and treatment are crucial to avoid long-term hip dysplasia and arthritis, which can cause difficulty in walking and discomfort. Breech presentation, in particular, is a significant risk factor for DDH, with spontaneous vaginal birth increasing the risk of hip pathology and instability compared to elective Caesarean section. However, whether breech presentation continues to be a risk factor for DDH in preterm children is unknown. Objective and methods This study aimed to investigate the prevalence of breech presentation and other gestational/delivery characteristics among newborns diagnosed with DDH. This retrospective study was conducted at Abha Maternity and Children Hospital, Abha, Saudi Arabia, over a period of six months. Data were collected from medical records of DDH cases diagnosed between 2016 and 2023. Data analysis was performed using Microsoft Excel (Microsoft Corporation, Redmond, Washington, United States) and IBM SPSS Statistics for Windows, Version 22 (Released 2013; IBM Corp., Armonk, New York, United States). Descriptive statistics and statistical tests were used to analyze the data. Results Most of the diagnosed children were female (86.7%), and bilateral hip dislocation (40%) was the most common presentation. X-ray was the most common diagnostic tool (48.3%), and operative management was the most common management strategy (73.3%). A positive family history of DDH was reported in more than one-third of cases. The study also analyzed the association between complications during pregnancy and various factors such as mode of delivery, presentation at delivery, gestational age at delivery, and associated maternal diseases. The difference in complication rates between women who delivered via C-section and those who delivered vaginally was insignificant (p = 0.14). Similarly, the difference in complication rates between women with breech and cephalic presentation was not statistically significant (p = 0.094). The difference in complication rates between women who delivered preterm, at term, or post-term was also not statistically significant (p = 0.578). Furthermore, the association between complications during pregnancy and pregnancy-associated maternal diseases was not statistically significant (p = 1.00). Conclusion DDH is a significant health issue in newborns, leading to long-term mobility problems and discomfort. Positive family history of DDH is a significant risk factor. Breech presentation was not significantly associated with DDH in preterm children, and no significant associations were found between complications during pregnancy and various factors. Early detection and treatment of DDH are crucial for preventing long-term complications. Family history should be considered an important risk factor, emphasizing the need for screening programs in families with a history of DDH.

Research on anterior minimally invasive approach in the treatment of children with developmental dysplasia of the hip

OBJECTIVES

To investigate the clinical efficacy and safety of open reduction through anterior minimally invasive approach in the treatment of children with developmental dysplasia of the hip.

METHOD

A total of 23 patients (25 hips) less than 2 years with developmental dysplasia of the hip treated by open reduction through anterior minimally invasive approach were treated in our hospital from August 2016 to March 2019. Through the anterior minimally invasive approach, we enter from the gap between sartorius muscle and tensor fasciae lata without cutting off rectus femoris muscle, which can effectively expose the joint capsule and reduce the damage to medial blood vessels and nerves. The operation time, incision length, intraoperative bleeding, hospital stay and surgical complications were observed. The progression of developmental dysplasia of the hip and avascular necrosis of the femoral head were evaluated by imaging examination.

RESULT

All patients were performed with follow-up visit for an average of 22 months. The average incision length was 2.5 cm, the average operation time was 26 min, the average intraoperative bleeding was 12ml, and the average hospital stay was 4.9 days. All patients received concentric reduction immediately after operation, and no re-dislocation occurred. At the last follow-up visit, the acetabular index was (25.8 ± 6.4°). During the follow-up visit, X-ray showed avascular necrosis of the femoral head in 4 hips (16%).

CONCLUSION

open reduction through anterior minimally invasive approach can achieve good clinical effect in the treatment of infantile developmental dysplasia of the hip.

Risk factors for misdiagnosis in children with developmental dysplasia of the hip: a retrospective single centre study

OBJECTIVE

To investigate risk factors of misdiagnosis at the first visit of children with developmental dysplasia of the hip (DDH) who did not participate in hip ultrasound screening.

METHODS

A retrospective review was conducted on children with DDH admitted to a tertiary hospital in northwestern China between January 2010 and June 2021. We divided the patients into the diagnosis and misdiagnosis groups according to whether they were diagnosed at the first visit. The basic information, treatment process and medical information of the children were investigated. We made a line chart of the annual misdiagnosis rate to observe the trend in the annual misdiagnosis rate. Univariate and multivariate logistic regression analyses were used to identify significant risk factors for missed diagnosis.

RESULTS

A total of 351 patients met the inclusion criteria, including 256 (72.9%) patients in the diagnosis group and 95 (27.1%) patients in the misdiagnosis group. The line chart of the annual rate of misdiagnoses among children with DDH from 2010 to 2020 showed no significant change trend. Multiple logistic regression analysis showed that the paediatrics department (v the paediatric orthopaedics department: OR 0.21, p<0.001), the general orthopaedics department (v the paediatric orthopaedics department: OR 0.39, p=0.006) and the senior physician (v the junior physician: OR 2.47, p=0.006) on the misdiagnosis at the first visit of children were statistically significant.

CONCLUSION

Children with DDH without hip ultrasound screening are prone to be misdiagnosed at their first visit. The annual misdiagnosis rate has not been significantly reduced in recent years. The department and title of the physician are independent risk factors for misdiagnosis.

Developmental Dysplasia of the Hip: How Many Risk Factors Are Needed?

Developmental dysplasia of the hip (DDH) is a progressive condition that lacks clear diagnostic and management protocols, due to insufficient data. While some advocate for universal screening, others recommend using risk factors as landmarks. In this study, we aimed to assess the risk factors associated with DDH incidence among a large population. We conducted a retrospective single-center multifactorial study between January 2019 and March 2022, including 3720 children who were investigated anamnestically, clinically, and through an ultrasound scan. We classified them into two groups: the control group with 3300 healthy children and the study group with 420 newborns diagnosed with DDH. Our analysis identified several risk factors associated with DDH, including gender, prematurity, non-vertex birth presentation, oligohydramnios, gestational diabetes, maternal hypertension, family history, associated deformities, and swaddling. We found that every DDH patient had at least two risk factors. Based on our findings, we recommend that children who present two or more risk factors for DDH be mandatorily evaluated sonographically, as well as children with clinical signs. DDH screening is recommended for each newborn for the long-term benefits of early detection and treatment.

Ambient temperature and major structural anomalies: A retrospective study of over 2 million newborns

BACKGROUND

Maternal exposure to ambient heat may be associated with congenital anomalies, but evidence is still limited.

OBJECTIVES

We aimed to estimate the association between maternal exposure to ambient heat during the 3-12 weeks post-conception (critical window of organogenesis) and risk of total and various diagnostic categories of major structural anomalies among live singleton births in the contiguous United States (US).

METHODS

We included data on 2,352,529 births with the first day of critical developmental windows falling within months of May through August from 2000 to 2004 across 525 US counties. We used a validated spatial-temporal model to estimate daily county-level population-weighted temperature. We used logistic regression to estimate the association between ambient temperature and risk of diagnostic categories of anomalies during the critical window after adjusting for individual and county-level factors. We conducted subgroup analysis to identify potential susceptible subpopulations.

RESULTS

A total of 29,188 anomalies (12.4 per 1000 births) were recorded during the study period. Maternal exposure to extreme heat (> 95th percentile) was associated with higher risk of total anomalies, central nervous system anomalies, and other uncategorized anomalies with an odds ratio (OR) of 1.05 (95 % CI: 1.00, 1.11), 1.17 (95 % CI: 1.01, 1.37), and 1.16 (95 % CI: 1.04, 1.29) compared with minimum morbidity temperature, respectively. The associations were homogeneous across subgroups defined by maternal age, maternal race/ethnicity, marital status, educational attainment, and parity, but were more pronounced among mothers residing in more socially vulnerable counties and births with multiple anomalies.

CONCLUSIONS

Among US live singleton births, maternal exposure to ambient heat may be associated with higher risk of total anomalies, central nervous system anomalies, and other uncategorized anomalies. We suggest additional research is carried out to better understand the relations between maternal heat exposure and congenital anomalies in the presence of global warming.

Known risk factors of the developmental dysplasia of the hip predicting more severe clinical presentation and failure of Pavlik harness treatment

PURPOSE

Developmental dysplasia of the hip (DDH) varies from mild instability of the hip to subluxation or total dislocation of the joint. Well-known risk factors of DDH include pre-natal breech position, female sex, positive family history, hip side, primiparity and the mode of delivery. Aim of the present study was to further evaluate known risk-factors of DDH, find associations with more severe dysplasia (characterized with Ortolani positivity) and find risk factors of failure of the Pavlik harness treatment.

MATERIAL AND METHODS

All children with the diagnosis of DDH treated in Tampere University hospital in the years 1998-2018 were retrospectively identified for the study and the data was collected from the medical records. Teratological dislocations (n = 3) were excluded from the analysis. Total of 945 patients were included.

RESULTS

Breech presentation was strongly associated with Ortolani positivity (p < 0.001). Breech presentation was not associated with ending up for spica casting and/or operative treatment (p = 0.291) despite the association with Ortolani positivity. Ortolani positivity (p = 0.002), positive family history (p = 0.013) and girl sex (p = 0.029) were associated with ending up for spica casting and/or operative treatment.

CONCLUSION

Breech presentation seems to increase the risk of Ortolani positive DDH. However, these infants are likely to recover with initially started Pavlik harness treatment, as it was not associated with elevated risk for undergoing more robust treatments. Positive family history and girl sex are associated with the most severe cases of developmental dysplasia of the hip, and it may predispose to the failure of the Pavlik harness treatment.

An Explorative Study into the Aetiology of Developmental Dysplasia of the Hip Using Targeted Urine Metabolomics

Developmental dysplasia of the hip (DDH) is the most prevalent congenital musculoskeletal disorder, yet its cause remains unknown. Adequate nutrient provision and coordinated electron exchange (redox) processes are critical for foetal growth and tissue development. This novel study sought to explore specific biochemical pathways in skeletal development for potential involvement in the aetiology of DDH. Spot urine samples were collected from infants, aged 13–61 days, with and without DDH. Ion chromatography-mass spectrometry was used to quantify thiosulphate, sulphate, nitrate, and phosphate, whilst nitrite was quantified using high-performance liquid chromato-graphy. Thiobarbituric acid reactive substances (TBARS) were measured as markers of lipid peroxidation. Creatinine and osmolality were determined by a 96-well plate assay and micro-osmometer to potentially normalise values for renal function, lean body mass, and hydration status. Urine samples were analysed from 99 babies: 30 with DDH and 69 age-matched non-DDH controls. Thiosulphate, TBARS, and creatinine concentrations differed between the DDH group and the controls (p = 0.025, 0.015, and 0.004 respectively). Urine osmolality was significantly lower in DDH compared to the controls (p = 0.036), indicative of the production of a more diluted urine in DDH infants. Following adjustment for osmolality, significant differences became apparent in urinary sulphate levels in DDH (p = 0.035) whereas all other parameters were similar between the groups. This is the first study to assess the potential role of these inorganic anions in DDH. The higher levels of sulphate found in infants with DDH suggests either enhanced intake from milk, increased endogenous formation, or impaired renal reabsorption. This investigation demonstrates the power of urine metabolomics and highlights the importance of normalisation for hydration status to disentangle developmental disorders. Our results strongly suggest that DDH is a systemic disease associated with altered uptake, formation, or handling of sulphate. There is potential for new opportunities in the prevention or treatment of DDH via nutritional intervention.

Concentric Circles: A New Ultrasonographic Sign for the Diagnosis of Normal Infantile Hip Development

Ultrasound (US) of the infant hip is used to diagnose developmental dysplasia of the hip (DDH). We present a new sonographic sign that describes the periphery of the femoral head and the acetabulum as two concentric circles.During 2008−2019, 3650 infants were referred for diagnosis of DDH. All underwent a clinical and US examination. We recorded the femoral head as the inner circle, within a fixed external circle, which was identified as the acetabulum. We analysed the clinical signs and risk factors. The US sign of two concentric circles was normal in 3522 infants and was classified as normal hip development. The alpha angle was >60° in 3449 (95%) infants. For the remaining 73 (5%) infants, the alpha angle was 50−60° and underwent further follow-up examination until the alpha angle was normalised. In 128 babies (3.5%), we detected the disruption of the concentric circle sign; the femoral head was found outside the acetabulum, which appeared with an upward sloping roof and the alpha angle was <50°. These infants had DDH and received appropriate treatment. Infants with a concentric circle sign and normal alpha angle are normal, whereas those with a disrupted sign are considered as having DDH.

Orthopedics and Trauma in Children: Key Problems and Future Insights

Orthopedic disorders among children are frequently encountered in clinical practice [...].

Whole exome sequencing of 28 families of Danish descent reveals novel candidate genes and pathways in developmental dysplasia of the hip

Developmental dysplasia of the hip (DDH) is a common condition involving instability of the hip with multifactorial etiology. Early diagnosis and treatment are critical as undetected DDH is an important cause of long-term hip complications. Better diagnostics may be achieved through genetic methods, especially for patients with positive family history. Several candidate genes have been reported but the exact molecular etiology of the disease is yet unknown. In the present study, we performed whole exome sequencing of DDH patients from 28 families with at least two affected first-degree relatives. Four genes previously not associated with DDH (METTL21B, DIS3L2, PPP6R2, and TM4SF19) were identified with the same variants shared among affected family members, in more than two families. Among known association genes, we found damaging variants in DACH1, MYH10, NOTCH2, TBX4, EVC2, OTOG, and SHC3. Mutational burden analysis across the families identified 322 candidate genes, and enriched pathways include the extracellular matrix, cytoskeleton, ion-binding, and detection of mechanical stimulus. Taken altogether, our data suggest a polygenic mode of inheritance for DDH, and we propose that an impaired transduction of the mechanical stimulus is involved in the etiopathological mechanism. Our findings refine our current understanding of candidate causal genes in DDH, and provide a foundation for downstream functional studies.

Geographical Distribution of Developmental Dysplasia of the Hip: A Brief Epidemiological Study of Iran

Background

Local epidemiological data are necessary to identify the disease hot spots and running screening programs. In this study, we evaluated the demographic characteristics of developmental dysplasia of the hip (DDH) in a tertiary referral hospital in Iran.

Methods

In a retrospective study, the medical profiles of 137 DDH children, who were referred to our university hospital between 2014 and 2020, were reviewed for characteristics such as gender, place of birth, age at the diagnosis, gestational age (term or preterm), twin or single birth, mother's age, pregnancy number, breech presentation, associated deformity, family history of DDH, et cetera.

Results

The study population included 24 (17.5%) boys and 113 (82.5%) girls with a mean age of 2.3 ± 2 years. In the majority of cases (54.2%), it was the firstborn. Twin delivery was seen in only 5 (4.1%) cases. The associated deformity was noticed in 17 (12.4%) patients. Clubfoot was the most commonly associated deformity that was seen in 6 of 17 (35.3%) patients. A family history of DDH was recorded in 12 (8.8%) patients. The breech presentation was recorded in 19 (13.9%) patients. The mean age of the mother at the delivery was 27.2 ± 6.1 years. Tehran, Lorestan, Kurdistan, and Khuzestan provinces had the most referrals.

Conclusion

DDH is associated with the female sex, positive family history, breech presentation at delivery, clubfoot deformity, and geographic district. These associations could be used for identifying the disease hot spots and running screening programs for earlier detection and better management of DDH.

Sex differences in musculoskeletal injury and disease risks across the lifespan: Are there unique subsets of females at higher risk than males for these conditions at distinct stages of the life cycle?

Sex differences have been reported for diseases of the musculoskeletal system (MSK) as well as the risk for injuries to tissues of the MSK system. For females, some of these occur prior to the onset of puberty, following the onset of puberty, and following the onset of menopause. Therefore, they can occur across the lifespan. While some conditions are related to immune dysfunction, others are associated with specific tissues of the MSK more directly. Based on this life spectrum of sex differences in both risk for injury and onset of diseases, a role for sex hormones in the initiation and progression of this risk is somewhat variable. Sex hormone receptor expression and functioning can also vary with life events such as the menstrual cycle in females, with different tissues being affected. Furthermore, some sex hormone receptors can affect gene expression independent of sex hormones and some transitional events such as puberty are accompanied by epigenetic alterations that can further lead to sex differences in MSK gene regulation. Some of the sex differences in injury risk and the post-menopausal disease risk may be "imprinted" in the genomes of females and males during development and sex hormones and their consequences only modulators of such risks later in life as the sex hormone milieu changes. The purpose of this review is to discuss some of the relevant conditions associated with sex differences in risks for loss of MSK tissue integrity across the lifespan, and further discuss several of the implications of their variable relationship with sex hormones, their receptors and life events.

Congenital hip dysplasia: The importance of early screening and treatment

Congenital Hip Dysplasia (CHD) is characterized by a hip joint dislocation between the femoral head and the acetabulum, with a multifactorial etiology. This disorder can be an isolated condition or the manifestation of a syndromic condition, and it has been estimated with higher rates than registered, with a predominance in female sex and left side; risk factors are now defined. In Italy, the incidence rate is 3-4%, with significant regional differences: higher in Lombardy and lower in Sicily. Because clinical examination alone is insufficient to diagnose CHD, it is supplemented with ultrasonography and X-ray if necessary. Surveillance, static or dynamic splints, or osteotomies are the only treatment options. The goal of this study was to evaluate our experience in terms of management and conservative treatment of all newborns from January 2018 to May 2022: female sex and left hip were major involved, risk factors were not significant in our case, but results from early diagnosis and treatments, in terms of better outcome, were interesting. After a strict 6-month follow-up period, 89.13% of the patients were classified as grade Ia or Ib according to the Graf classification system. Finally, we emphasize the importance of early universal screening and subsequent diagnosis to allow for early treatment of the disorder, at an age when conservative treatments can yield good results.

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.

Clinical Efficacy and Safety of Ibuprofen plus Traction, Reposition, and Hip Spica Cast in the Treatment of Developmental Dysplasia of the Hip

Objective. To assess the clinical efficacy and safety of ibuprofen plus traction, reposition, and hip spica cast in the treatment of developmental dysplasia of the hip (DDH). Methods. Between January 2019 and July 2020, 60 children with DDH treaded in department of orthopedics of our institution were assessed for eligibility and recruited. They were assigned at a ratio of 1 : 1 to receive either traction + reposition + hip spica cast plus analgesia pump (observation group) or traction + reposition + hip spica cast plus analgesia pump and oral ibuprofen (control group). The outcome measures included clinical efficacy, pain scores, unexpected pain calls, the dosage of analgesia pump, and adverse events. Results. The two groups had similar clinical efficacy ( $P>0.05$ ). The patients given oral ibuprofen were associated with significantly lower pain scores at 24 h and 72 h postoperatively versus those without oral ibuprofen ( $P<0.05$ ). Analgesics with oral ibuprofen resulted in fewer unexpected pain calls versus analgesics without oral ibuprofen within 72 h postoperatively ( $P<0.05$ ). The application of oral ibuprofen in the analgesia pump showed great improvement in lowering the dosage of analgesia pump versus the absence of ibuprofen ( $P<0.05$ ). The incidence of adverse events was similar between the two groups of patients ( $P>0.05$ ). Conclusion. Traction + reposition + hip spica cast plus analgesia pump and oral ibuprofen effectively mitigated postoperative pain in children with DDH and reduces analgesic drug dosage with a high safety profile.

Developmental Dysplasia of the Hip: Controversies in Management

PURPOSE OF REVIEW

Many aspects of developmental hip dysplasia (DDH) care and evaluation are still active areas of debate. Recent studies have provided more insight into these topics such as strategies for reducing osteonecrosis, assessing hip reduction after closed and open reduction, and the management of residual acetabular dysplasia.

RECENT FINDINGS

The presence of the ossific nucleus at the time of reduction does not alter the risk of osteonecrosis. The risk of osteonecrosis may be higher when hips are immobilized in excessive abduction. Limited sequence MRI may be the best choice for assessing hip reduction after closed and open reduction; however, new technologies are emerging such as 3D fluoroscopy and perfusion MRI. The treatment of residual acetabular dysplasia with bracing has been shown to be effective and the decision to perform a pelvic osteotomy is based on patient-specific factors. The spectrum of DDH treatment has evolved over the past several decades. Recent studies have provided insights into strategies for osteonecrosis prevention, hip evaluation during after reduction, and the management of residual acetabular dysplasia. However, there is ample room for additional and more rigorous studies guiding advanced imaging for assessing hip reduction such as 3D fluoroscopy and perfusion MRI, as well as the management of residual acetabular dysplasia.

Outcome Prognostic Factors in MRI during Spica Cast Therapy Treating Developmental Hip Dysplasia with Midterm Follow-Up

Closed reduction followed by spica casting is a conservative treatment for developmental dysplasia of the hip (DDH). Magnetic resonance imaging (MRI) can verify proper closed reduction of the dysplastic hip. Our aim was to find prognostic factors in the first MRI to predict the possible outcome of the initial treatment success by means of ultrasound monitoring according to Graf and the further development of the hip dysplasia or risk of recurrence in the radiological follow-up examinations. A total of 48 patients (96 hips) with DDH on at least one side, and who were treated with closed reduction and spica cast were included in this retrospective cohort study. Treatment began at a mean age of 9.9 weeks. The children were followed for 47.4 months on average. We performed closed reduction and spica casting under general balanced anaesthesia. This was directly followed by MRI to control the position/reduction of the femoral head without anaesthesia. The following parameters were measured in the MRI: hip abduction angle, coronal, anterior and posterior bony axial acetabular angles and pelvic width. A Graf alpha angle of at least 60° was considered successful. In the radiological follow-up controls, we evaluated for residual dysplasia or recurrence. In our cohort, we only found the abduction angle to be an influencing factor for improvement of the DDH. No other prognostic factors in MRI measurements, such as gender, age at time of the first spica cast, or treatment involving overhead extension were found to be predictive of mid-term outcomes. This may, however, be due to the relatively small number of treatment failures.

An evaluation of clinical and ultrasound results of Pavlik harness treatment for developmental dysplasia of the hip

Developmental dysplasia of the hip (DDH) is the instability or dislocation of the hip joint at birth that may occur in utero, during infancy, and childhood. This condition was identified as an important challenge. This study aimed to determine the clinical and ultrasound results of Pavlik harness treatment for DDH in patients referred to the pediatric clinic of Imam Khomeini Hospital in Ahvaz. This is a descriptive cross-sectional study in which 100 newborns aged 15 to 30 days were included by the census method after obtaining parental consent. Follow-up of the infants was performed at 3 and 6 months after treatment. All analyzes were performed using SPSS version 22 at a significance level of 0.05. The results showed that the mean age of the infants was 23.46±2.12 days, of which 33 infants were boys and 67 girls. The involvement on the right and left sides was 39% and 50%, respectively, and 11% of the infants had bilateral involvement. The mean value of acetabular index before placement was 25.48±6.509 and 26.38±3.866 on the right and left sides, which after 3 months of placement, was reduced to 21.62±2.578 and 21.57±2.839, respectively. Pavlik harness treatment was associated with acceptable radiological results in infants. This technique seems to be a suitable and applicable attempt to treat this problem and prevent serious and irreversible complications of late diagnosis.

Comprehensive bioinformatics analysis of susceptibility genes for developmental dysplasia of the hip

Developmental dysplasia of the hip (DDH) is a multifactorial disease, which occurs under environmental and genetic influence. The etiopathogenesis of DDH has not been fully explained. As research progresses, many candidate genes have been found to be closely related to the occurrence of DDH. In this study, we comprehensively examined 16 susceptibility genes of DDH using bioinformatics. COL1A1 encodes the pro-alpha1 chains of type I collagen, which is the major protein component of the bone extracellular matrix (ECM). The genes displaying the most statistically significant co-expression link to COL1A1 are ASPN, TGFB1, DKK1, IL-6, TENM3 and GDF5. DKK1, FRZB and WISP3 are components of the Wnt signaling pathway. CX3CR1 and GDF5 regulate chondrogenesis through the canonical Wnt signaling pathway. ASPN could induce collagen mineralization through binding with collagen and calcium. Integrated bioinformatics analysis indicates that ECM, Wnt signaling pathway and TGF-β signaling pathway are involved in the occurrence of DDH. These provide a basis for further exploring the pathogenesis of DDH.

Case Report: Diagnosis of Mucopolysaccharidosis Type IVA With Compound Heterozygous Galactosamine-6 Sulfatase Variants and Biopsy of Replaced Femoral Heads

INTRODUCTION

Mucopolysaccharidosis Type IVA (MPS IVA) or Morquio A Syndrome, is a rare metabolic disorder caused by compromised galactosamine-6 sulfatase (GALNS) encoded by GALNS gene (NM_000512.5), leading to keratin sulfate (KS), and chondroitin-6-sulfate accumulation in various organs. We present a 17-year-old woman with progressive bilateral hip pain and radiographic evidence of spondyloepiphyseal dysplasia.

METHODS

Diagnosis of MPS IVA was made based on whole-exome sequencing (WES) of blood samples collected from the patient and family members, high urinary glycosaminoglycan excretion, supportive clinical manifestations, radiographic examinations, including whole-body X-rays, cervical MRI, and pelvic CT. The patient underwent bilateral total hip arthroplasties sequentially, at a 1-month interval. Femoral heads were preserved for the micro-CT (μCT) analysis and the osteochondral histology examination.

RESULTS

The patient presented with multiple skeletal deformities, including vertebras and long bone deformities. WES disclosed compound heterozygous variants at exon 11 (c.1156C>T) and exon 12 (c.1288C>G) of the GALNS (NM_000512.5). The μCT analysis revealed significant bone quantity loss and microarchitectural change in both weight-bearing area (WBA) and non-weight-bearing area (NWBA) of the femoral heads, while histological analysis showed structural abnormity of articular cartilage in the WBA of the femoral heads.

CONCLUSION

We have found compound heterozygous variants of GALNS. This is also the first study to report the microarchitectural and histological changes of both subchondral bone and articular cartilage of the femoral head in a patient with MPS IVA.

DDH in the Walking Age: Review of Patients with Long-Term Follow-Up

INTRODUCTION

The best treatment option in children with late detected DDH is still a subject of much controversy and only few studies have investigated the long-term outcome of treatment in such patients. We performed a systematic review to assess long-term outcome of late detected DDH hips treated after walking age.

METHODS

Studies met inclusion criteria if they: (1) reported at least 30 hips treated; (2) included children aged between 9 months and 12 years; (3) treatment indication was late detected DDH after walking age; (4) presented a minimum follow-up of 10 years; (5) reported a clinical or radiological outcome. The Kaplan-Meier method was used to evaluate long-term survival according to clinical and radiological outcomes. The rate of total hip replacement (THR) was retrieved.

RESULTS

From a total of 6561 articles, 13 articles with grade IV level of evidence were included in our review. A total of 988 hips in 800 patients with a mean follow-up of 27.9 years (range 10-67) were included. The mean age at surgery was 3.3 years (range, 9 months-12 years). The rate of THR increased according to the length of final follow-up. In particular, all studies reported no case of THR at 23.5 years of follow-up, a rate of 10.2% of THR between 30 and 40 years of follow-up and a rate of 35.6% of THR in patients with follow-up more than 40 years.

CONCLUSIONS

In patients with late detected DDH, most THR became necessary more than 30 years after the index procedure and their number increased further after 40 years and more of follow-up. Late detected DDH diagnosed after walking age is a life-long disease.