Prenatal limb defects: Epidemiologic characteristics and an epidemiologic analysis of risk factors

"As a parent, I want to do more for my child": A phenomenological approach to understanding the experiences of parents involved in surgical decision-making for children with congenital hand anomalies

BACKGROUND

A congenital anomaly of the hand can affect both function and appearance, and places a stressful psychological burden on the family, especially parents. Surgery during infancy may prevent later disabilities, but little is known of the importance of parents' involvement in these decisions in terms of psychological adjustment or treatment satisfaction.

OBJECTIVE

To understand parents' perceptions of involvement in their child's surgery for limb anomaly, and their preferences for the support of healthcare professionals. Results should lead to recommended interventions to improve familial adjustment to the child's condition.

METHODS

Qualitative data was collected from semi-structured confidential self-reported interviews of 35 parents (65.7 % mothers) of children who had received reconstructive surgery for congenital hand anomaly (at age 24.89 ± 9.26 months); interviews were coincident with the 1-month postoperative follow-up. The parents ranged in age, gender, educational background, economic status, and type of anomaly. Data analysis referenced Colaizzi's phenomenological approach.

RESULTS

The concerns of the parents were consolidated into three themes: attitudes toward Parental involvement in surgical decision-making; status of parental involvement in Surgical decision-making; and need for help and support.

CONCLUSION

Some parents were comfortable leaving surgical decisions entirely to the medical staff, but most preferred active participation and were disappointed at their lack of inclusion. The maximum benefit from surgery for congenital abnormalities in infancy is achieved when the parents and extended families have access to the expertise, skills, encouragement, and psychological support of healthcare providers.

The Frontal Phocomelia in a 3-Year-Old Girl

Background: Phocomelia is a congenital limb deformity in which the proximal part of the upper or lower limb does not develop. Occasionally the malformed limb may be located ectopically. Case report: We present a frontal phocomelia in a three-year-old girl with right-hand phocomelia and thoracoschisis. The patient's arm was connected directly from the front of the chest, with a rudimentary thumb and two fingers. The truncated arm was not functional. The acromioclavicular joint was abnormal and ectopic, the limb articulated with the medial side of sternum. The thoracoschisis manifested as eventration of the right liver lobe and right side of chest wall. Conclusion: Ectopic phocomelia can be associated with thoracoschisis, it can be nonfunctional, and can articulate with the sternum.

A novel smoothed (SMO) point mutation in congenital tibial hemimelia: a case report

BACKGROUND

Congenital tibial hemimelia (CTH [MIM: 275220]) is a rare congenital limb deficiency that manifests as a shortened, curved, dysplastic or absent tibia with polydactyly. In previous studies, mutations of a distant sonic hedgehog (SHH) cis-regulator (ZRS) and a Shh repressor (GLI3) were identified.

CASE PRESENTATION

Here, we admitted a 20-month-old boy who manifested with right tibial deformity, varus foot, ankle dislocation, and ipsilateral preaxial polydactyly. After genetic sequencing and data analysis, the results revealed a 443 A > G mutation in the father and a 536 C > T mutation in the mother in exon 2 of the Smoothed (SMO) gene at 7q32.1, with the coexistence of both mutant alleles in the proband/patient.

CONCLUSIONS

Our report suggests that even though not previously reported, SMO mutations may be associated with limb anomalies such as tibial hemimelia via Hh signaling in humans and has implications for genetic counseling.

Maternal Cigarette Smoking and Congenital Upper and Lower Limb Differences: A Systematic Review and Meta-Analysis

Maternal smoking during pregnancy has been associated with adverse effects on foetal development, including congenital limb anomalies. This systematic review aimed to provide an updated assessment of the association between maternal smoking during pregnancy and the risk of congenital limb anomalies. A systematic search was conducted to identify relevant studies published up to February 2023. Studies reporting on the relationship between maternal smoking during pregnancy and congenital digital anomalies or congenital limb reduction defects were included. Two independent reviewers screened the studies, extracted data, and assessed the quality of the included studies. Meta-analyses were performed to estimate the pooled odds ratios with 95% confidence intervals using fixed and random-effects models. In total, 37 publications comprising 11 cohort and 26 case-control studies were included in the systematic review. The meta-analysis demonstrated a significant increased risk of congenital limb reduction defects (pooled OR: 1.27, 95% CI: 1.18-1.38) in infants born to mothers who smoked during pregnancy. Similarly, a significant relationship was observed for the development of polydactyly/syndactyly/adactyly when considered as a single group (pooled OR: 1.32, 95% CI: 1.25-1.40). Yet, in contrast, no significant association was observed when polydactyly (pooled OR: 1.06, 95% CI: 0.88-1.27) or syndactyly (pooled OR: 0.91, 95% CI: 0.77-1.08) were considered individually. This systematic review provides updated evidence of a significant relationship between maternal smoking during pregnancy and increased risk of congenital limb anomalies. These findings highlight the potential detrimental effects of smoking on foetal limb development and underscore the importance of smoking cessation interventions for pregnant women to mitigate these risks.

The role of chondrocyte-to-osteoblast trans-differentiation in fetal bone dysplasia of mice caused by prenatal exposure to dexamethasone

Maternal exposure to dexamethasone can cause developmental toxicity of long bones in offspring. However, the effect of dexamethasone on the trans-differentiation of growth plate chondrocytes into osteoblasts and its role in bone dysplasia of fetuses caused by prenatal dexamethasone exposure (PDE) remains unclear. In this study, pregnant mice were treated with different doses, stages, and courses of dexamethasone according to clinical practice to reveal the phenomenon. Further, growth plate chondrocytes were treated with dexamethasone in vitro to clarify the phenomenon and mechanism. The results showed that PDE caused dysplasia of fetal long bones in female and male mice, accompanied by the delayed formation of the primary ossification center and the widening hypertrophic zone of growth plate cartilage. Meanwhile, PDE increased the number of hypertrophic chondrocytes at growth plate cartilage and decreased the number of osteoblasts at the primary ossification center. Moreover, PDE significantly decreased the expression of osteogenic transcription factor Runx2 but increased the expression of hypertrophic chondrocytes marker Col10. These above phenomena were more significant in the high dose, early stage, and double courses of dexamethasone exposure groups, and the male fetal mice showed more obvious than the female fetal mice. In vitro, dexamethasone significantly inhibited the trans-differentiation of growth plate chondrocytes into osteoblasts, accompanied by a decrease in Runx2 expression and an increase in Col10 expression. In conclusion, this study revealed the phenomenon and mechanism of fetal bone dysplasia caused by PDE from the new perspective of trans-differentiation disorder of growth plate chondrocytes to osteoblasts.

COVID-19 AND UPPER LIMB ANOMALIES IN NEWBORNS: A REASON FOR CONCERN?

The relationship between viral infection in pregnancy and congenital anomalies is reported in the medical literature. The risks for the SARS-CoV-2 virus interfering with implantation, growth, and fetal development are not yet known. Many drugs with potential teratogenic risk are being used for treatment. The studies with the vaccine excluded pregnant women from clinical trials, currently preventing high-quality evidence. We present a review of the most common anomalies in the upper extremities caused by congenital viral infection and the risks of anti-COVID-19 therapy and vaccine during pregnancy. We aim to alert orthopedic and hand surgeons to the possibility of these conditions in the future. Level of evidence V; Narrative review.

Prenatal Diagnosis of Clubfoot: Where Are We Now? Systematic Review and Meta-Analysis

The primary methods for prenatal diagnosis of Clubfoot are ultrasound (US) and magnetic resonance imaging (MRI). An ultrasound is performed between the 1st trimester and the 28th week of pregnancy and it is reported to be used as a diagnostic method alone or in combination with MRI. So far, an international consensus on the most effective screening method has not been reached. This systematic review and meta-analysis were performed to establish the most effective and reliable exam for prenatal diagnosis of Clubfoot. The literature search was conducted using a PIOS-approach from May 2021 to June 2021. Studies reporting cases of prenatal diagnosis of Clubfoot made through US and MRI conducted from January 2010 to June 2021 were included in the study and reviewed by 2 authors. The 23 selected studies included 2318 patients. A total of 11 of the studies included details on the accuracy, while the rest were used to obtain information about the primary methodology utilized. In all the selected studies, US was used as the primary diagnostic instrument. Thirteen of the studies used the US exclusively, while three used MRI in addition to US and seven performed karyotyping after US diagnosis. The US has been shown to be the instrument of choice for the prenatal diagnosis of Clubfoot. International guidelines for an ultrasonography classification of congenital clubfoot are required to reduce the inter-variability accuracy of this procedure.

MR Virtual Endoscopy of the Fetal Limb Anomalies Using Three-Dimensional Fast Imaging Employing Steady-State Acquisition Sequence

OBJECTIVE

To retrospectively investigate the feasibility of magnetic resonance virtual endoscopy (MRVE) to visualize the normal limbs and limb deformities Methods: MR sequences included two-dimensional (2D) single fast spin-echo sequence and 2D and 3D steady-state procession fast imaging sequences. MRVE reconstruction was retrospectively performed by 2 radiologists in 32 fetuses in 30 pregnant women. The correlation between the radiologists for the virtual endoscopy threshold of MRVE was determined. Image quality and limb segment visibility were independently rated. Area under the receiver operating characteristics curve (AUC) of 2D MRI and MRVE was calculated.

RESULTS

The mean virtual endoscopy threshold required for the visualization of the limb was 991.93 ± 12.13 and 991.83 ± 12.26 for 2 radiologists, respectively. The correlation between the radiologists for virtual endoscopy threshold was excellent (r = 0.933). The weighted kappa statistic was 0.96 for the evaluation of image quality of limb segments, indicating excellent interobserver agreement. Compared to that of 2D MRI alone, a higher AUC of 2D MRI with MRVE was achieved in detection of both upper and lower limb deformities (0.91 vs. 0.69 and 0.83 vs. 0.71, respectively).

CONCLUSION

MRVE may display normal and abnormal fetal limb orientation and structures from multiple perspectives and provide incremental information for obstetrics.

Maternal exposure to ambient SO2 and risk of polydactyly and syndactyly: a population-based case-control study in Liaoning Province, China

Evidence links exposure to maternal sulfur dioxide (SO₂) and the risk of limb defects have been inconsistent. To investigate associations between SO₂ exposure during preconception and the first trimester and risks of polydactyly and syndactyly. The study population was acquired from the Maternal and Child Health Certificate Registry of Liaoning Province between 2010 to 2015, and consisted of 2605 polydactyly, 595 syndactyly cases, and 7950 controls. Ambient air pollutants levels were retrieved from air quality monitoring stations. We used multivariable logistic regression model to assess the adjusted odds ratios (ORs) and 95% confidence intervals (CIs). We found that exposure to increased SO₂ concentrations was associated with polydactyly during both the 3 months preconception (OR_{Q4 vs. Q1} = 3.76; 95% CI 2.61, 5.42; per 10 μg/m³ increment: OR = 1.07; 95% CI 1.04, 1.10) and the first trimester (OR_{Q4 vs. Q1} = 2.03; 95% CI 1.41, 2.92; per 10 μg/m³ increment: OR = 1.07; 95% CI 1.03, 1.11). However, we only observed increased risk for syndactyly in the analysis of high vs. low quartiles (three months preconception: OR_{Q4 vs. Q1} = 3.72; 95% CI 2.05, 6.75; first trimester: OR_{Q4 vs. Q1} = 1.98; 95% CI 1.11, 3.51). Most results of analyses based on single-month exposure window generally showed similar positive associations. Additionally, these findings were broadly consistent across subgroups and sensitivity analyses. Maternal SO₂ exposure increase the risk of polydactyly and syndactyly.

The Effects of Parent Ages on Birth Defects

BACKGROUND

Men and women, in the United States, are having children at considerably older ages. This changing demographic has been associated with multiple neonatal adverse birth outcomes that are currently considered to constitute a major public health crisis. The objective of this study was to evaluate the risk of parent age on birth defects and to provide results that can serve as a starting point for more specific mediation modeling. The modeling estimated the effects of parent age on birth defects controlling for confounding between maternal and paternal age and separated the mediating effect of chromosomal disorders, including Down syndrome.

METHODS

Data containing approximately 15,000,000 birth records were obtained from the United States Natality database for the years 2014 to 2018. A Bayesian modeling approach was used to estimate adjusted risks of parent ages both unadjusted and adjusted for the other parent's age and for the mediational effect of chromosomal disorders, including Down syndrome.

RESULTS

Increasing maternal age was associated with increased risks for hypospadias and cyanotic congenital heart disease. Increasing maternal and paternal ages were associated with decreasing risks for gastroschisis. For limb reduction defect, cleft lip and all defects combined, the risk of maternal age was U-shaped with the lowest risks observed at approximately age 35y. Paternal age was not associated with an increase in the birth prevalence of birth defects.

CONCLUSION

Advancing maternal age was associated with increased birth prevalence of hypospadias and cyanotic congenital heart disease and associated with a lower birth prevalence for gastroschisis. Both older and younger maternal ages were related to limb reduction defect and cleft lip. Advancing paternal age was not associated with an increased birth prevalence of birth defects but was associated with a decreased birth prevalence of gastroschisis.

[Genital abnormalities: Contextualization of a neglected area in prenatal diagnosis]

OBJECTIVE

To reflect on how the area of genital abnormalities has fallen behind in prenatal diagnosis.

METHODS

Based on the thesis that prenatal diagnosis of genital abnormalities has scarcely developed, a comparison with other areas of prenatal diagnosis and with its postnatal counterpart is presented; different explanations for this situation are examined; and a reflection is presented on ways to expand this field of knowledge.

CONCLUSIONS

Compared to other disciplines, prenatal diagnosis of genital abnormalities finds itself lagging behind in terms of diagnostic tools, management protocols and scientific literature. Potential causes include a perception of low prevalence and limited importance, or exploration challenges. Integration of current knowledge, together with the acquisition of the appropriate tools and translation to clinical medicine, would be a way to make this discipline stronger.