Narrative Review on the Role of Imaging in DDH

Acetabular index and acetabular depth ratio in newborns and infants aged 6 months or less with the healthy development of hips: A retrospective cross-sectional study

Radiographic assessment of the hip may render critical in the diagnosis of developmental dysplasia of the hip (DDH) in newborns and infants aged ≤6 months. There is no complete dataset on the acetabular index (AI) and acetabular depth ratio (ADR) values in this age group. The objective of this study was to assess the AI and ADR values in newborns and infants aged ≤6 months with healthy development. A retrospective analysis was performed on pelvic radiographs of newborns and infants (≤6 months) between August 2020 and September 2021. There were 3000 children with pelvic radiographic imaging. Normal sonographic findings and radiographs without any structural deformity of the hip were inclusion criteria. A total of 1132 newborns and infants (2264 hips) were analyzed. Measurements of AI and ADR (ischium and pubic bone as landmarks for acetabular depth ratio A [ADR-A] and acetabular depth ratio B [ADR-B]) were performed. Correlation and intraclass correlation coefficient (ICC) values were calculated. Left-sided AI values were significantly higher than the right-sided AI values, except in infants aged 4 to ≤5 months (P < .05). ADR-B values differed significantly between male and female newborns and infants both in terms of the side of the hip measured and age (P < .05). AI values were fairly correlated with age (r = -0.286 for left and r = -0.254 for right) in the negative direction and with ADR-A (r = 0.449 and r = 0.469 for left and right) and ADR-B (r = 0.545 and r = 0.592 for left and right) in the positive direction. Inter-observer ICC was 0.845 to 0.989 (excellent) for AI, 0.534 and 0.904 (moderate to excellent) for ADR-A, and -0.014 and 0.774 (slightly good to good) for ADR-B. Intra-observer ICC was 0.811 to 0.996 (excellent) for AI, 0.575 to 0.98 (moderate to excellent) for ADR-A, and 0.023 to 0.954 (slightly good to excellent) for ADR-B. This study features the first complete data set of AI and ADR measurements, which are essential for pelvic radiographic imaging of hip dysplasia, in newborns and infants aged ≤6 months.

Application of statistical shape modeling to the human hip joint: a scoping review

OBJECTIVE

The objective of this scoping review was to identify all examples of the application of statistical shape models to the human hip joint, with a focus on applications, population, methodology, and validation.

INTRODUCTION

Clinical radiographs are the most common imaging tool for management of hip conditions, but it is unclear whether radiographs can adequately diagnose or predict outcomes of 3D deformity. Statistical shape modeling, a method of describing the variation of a population of shapes using a small number of variables, has been identified as a useful tool to associate 2D images with 3D anatomy. This could allow clinicians and researchers to validate clinical radiographic measures of hip deformity, develop new ones, or predict 3D morphology directly from radiographs. In identifying all previous examples of statistical shape modeling applied to the human hip joint, this review determined the prevalence, strengths, and weaknesses, and identified gaps in the literature.

INCLUSION CRITERIA

Participants included any human population. The concept included development or application of statistical shape models based on discrete landmarks and principal component analysis. The context included sources that exclusively modeled the hip joint. Only peer-reviewed original research journal articles were eligible for inclusion.

METHODS

We searched MEDLINE, Embase, Cochrane CENTRAL, IEEE Xplore, Web of Science Core Collection, OCLC PapersFirst, OCLC Proceedings, Networked Digital Library of Theses and Dissertations, ProQuest Dissertations and Theses Global, and Google Scholar for sources published in English between 1992 and 2021. Two reviewers screened sources against the inclusion criteria independently and in duplicate. Data were extracted by 2 reviewers using a REDCap form designed to answer the review study questions, and are presented in narrative, tabular, and graphical form.

RESULTS

A total of 104 sources were considered eligible based on the inclusion criteria. From these, 122 unique statistical shape models of the human hip were identified based on 86 unique training populations. Models were most often applied as one-off research tools to describe shape in certain populations or to predict outcomes. The demographics of training populations were skewed toward older patients in high-income countries. A mean age between 60 and 79 years was reported in 29 training populations (34%), more than reported in all other age groups combined, and 73 training populations (85%) were reported or inferred to be from Europe and the Americas. Only 4 studies created models in a pediatric population, although 15 articles considered shape variation over time in some way. There were approximately equal numbers of 2D and 3D models. A variety of methods for labeling the training set was observed. Most articles presented some form of validation such as reporting a model's compactness (n = 71), but in-depth validation was rare.

CONCLUSIONS

Despite the high volume of literature concerning statistical shape models of the human hip, there remains a need for further research in key areas. We identified the lack of models in pediatric populations and low- and middle-income countries as a notable limitation to be addressed in future research.

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.

Comparison of Transfer Learning Models in Pelvic Tilt and Rotation Measurement in Pediatric Anteroposterior Pelvic Radiographs

The rotation and tilt of the pelvis during anteroposterior pelvic radiography can lead to misdiagnosis of developmental dysplasia of the hip (DDH) in children. At present, no method exists for accurately and conveniently measuring the precise rotation and tilt angles of pelvic on radiographs. The objective of this study was to develop several rotation and tilt measurement models using transfer learning and digital reconstructed radiographs (DRRs), and to compare their performances on pelvic radiographs. Based on the inclusion criteria, 30 of 92 children who underwent 3D hip CT scans at Xijing Hospital from 2015 to 2020 were included in the study. Using DRR techniques, radiographs were generated by rotating and tilting the pelvis in CT datasets at - 12 to 12° (projected every 3°) and were randomized to a 2:1:1 ratio of training dataset, validation dataset, and test dataset. Five pre-trained networks, including VGG16, Xception, VGG19, ResNet50 and InceptionV3 were used to develop pelvic rotation measurement models and tilt measurement models, and these models were trained with training dataset. The callback function was used during the training to slow down the learning rate when learning was stalled. Then, the validation set was used to optimize each model and compare their performances. At last, we tested the final performances of optimal rotation measurement model and optimal tilt measurement model on test dataset. The mean absolute error (MAE) was employed to assess the performance of the models. A total of 2430 pelvic DRRs were collected based on 30 CT datasets. Among 5 pre-trained transfer learning models, VGG16-Tilt achieved the best tilt prediction performance at the same BS and different LR. VGG16-Tilt model achieved its best performance on validation set at LR = 0.001 and BS = 4, and the final MAE on the test set was 0.5250°. In terms of rotation prediction, VGG16-Rotation also achieved the best performance, and it achieved its best performance on validation set at LR = 0.002 and BS = 8. The final MAE of VGG16-Rotation on the test set was 1.0731°. Pretrained transfer learning models worked well in predicting tilt and rotation angles of the pelvis on radiographs in children. Among them, VGG16-Tilt and VGG16-Rotation had the best effect in dealing with such problems despite their simple structures. These models deployed in devices can give orthopedic surgeons a powerful aid in DDH diagnosis.

Incidence of Neonatal Developmental Dysplasia of the Hip and Late Detection Rates Based on Screening Strategy: A Systematic Review and Meta-analysis

IMPORTANCE

Universal ultrasonographic screening for developmental dysplasia of the hip (DDH) has gained increasing popularity despite the lack of benefit in terms of reducing the rates of late-detected cases (age ≥12 weeks) in randomized clinical trials.

OBJECTIVE

To report the reported incidence of DDH in the English scientific literature and compare rates of late-detected cases in settings with different DDH screening strategies.

DATA SOURCES

PubMed, Scopus, and Web of Science databases were searched on November 25 and 27, 2021. No time filters were used in the search.

STUDY SELECTION

All observational studies reporting the incidence of early-detected or late-detected (age ≥12 weeks) DDH were included. Non-English reports were excluded if the abstract did not include enough information to be included for analysis.

DATA EXTRACTION AND SYNTHESIS

The number of newborns screened and the detection rates were extracted. Meta-analysis calculated the pooled incidence of DDH per 1000 newborns with 95% CIs using a random- or fixed-effects model. This study is reported according to the PRISMA and MOOSE guidelines.

MAIN OUTCOMES AND MEASURES

The main outcome measures were early detection, early treatment, late detection, and operative treatment incidences.

RESULTS

A total of 1899 studies were identified, 203 full texts were assessed, and 76 studies with 16 901 079 infants were included in final analyses. The early detection rate was 8.4 (95% CI, 4.8-14.8) infants with DDH per 1000 newborns with clinical screening, 4.4 (95% CI, 2.4-8.0) infants with DDH per 1000 newborns with selective ultrasonographic screening, and 23.0 (95% CI, 15.7-33.4) infants with DDH per 1000 newborns with universal ultrasonographic screening. Rates for nonoperative treatment were 5.5 (95% CI, 2.1-14) treatments per 1000 newborns with clinical screening, 3.1 (95% CI, 2.0-4.8) treatments per 1000 newborns with selective ultrasonographic screening, and 9.8 (95% CI, 6.7-14.4) treatments per 1000 newborns with universal ultrasonographic screening. The incidence of late-detected DDH was 0.5 (95% CI, 0.2-1.5) infants with DDH per 1000 newborns with clinical screening, 0.6 (95% CI, 0.3-1.3) infants with DDH per 1000 newborns with selective ultrasonographic screening, and 0.2 (95% CI, 0.0-0.8) infants with DDH per 1000 newborns with universal ultrasonographic screening. The corresponding incidences of operative treatment were 0.2 (95% CI, 0.0-0.9) operations per 1000 newborns with clinical screening, 0.5 (95% CI, 0.4-0.7) operations per 1000 newborns with selective ultrasonographic screening, and 0.4 (95% CI, 0.2-0.7) operations per 1000 newborns with universal ultrasonographic screening.

CONCLUSIONS AND RELEVANCE

This meta-analysis found that early detection rates and nonoperative treatments were higher with universal screening. The late detection and operative treatment rates with universal screening were similar to those among selectively and clinically screened newborns. Based on these results, universal screening may cause initial overtreatment without reducing the rates of late detection and operative treatment.