What is new in idiopathic clubfoot?

Epidemiological characterization of clubfoot: a population-based study of a surveillance program in Colombia

Clubfoot is a common musculoskeletal congenital abnormality, with a prevalence of 5-20 cases per 10 000 live births in low to middle-income countries. If left untreated, clubfoot causes severe consequences for the child: gait disturbances, reduced quality of life, and limited work opportunities. Our objective was to characterize clubfoot and determine its prevalence and associated risk factors in Bogotá and Cali, Colombia, from 2002 to 2020. A retrospective case-control study design was employed, analyzing data from birth defect reports provided by the Program for the Prevention and Follow-up of Congenital Defects and Orphan Diseases surveillance system. Cases included live births or stillbirths with clubfoot, while controls consisted of infants without congenital abnormalities, matched in terms of birth date and hospital. Prevalence was calculated considering a 95% confidence interval using Poisson distribution, and risk factors were assessed through adjusted odds ratios obtained by logistic regression model. Of 558 255 births, 861 cases of clubfoot were identified, 48.20% were postural clubfoot, and 15 cases were syndromic clubfoot. In Bogota, prevalence rate was 15.1 per 10 000 live births, whereas in Cali it was 17.29 per 10 000 live births. Family history of clubfoot within first-degree relatives was identified as a risk factor for clubfoot. Investigating risk factors for clubfoot holds significant importance in terms of preventing and reducing morbidity within this population. Helping to drive government and healthcare initiatives aimed at providing timely and effective treatment.

Incidence and prevalence of congenital clubfoot in Apulia: a regional model for future prospective national studies

BACKGROUND

Congenital clubfoot is a fairly common and severe congenital malformation, most often of idiopathic origin. A smaller percentage of cases is related to chromosomal abnormalities and genetic syndromes. It is estimated that 0.5/1000 newborns are affected worldwide, with a male to female ratio of 2:1 and greater distribution in developing countries (80%). The "European Surveillance of Congenital Anomalies (EUROCAT)" reported clubfoot prevalence in European newborns, but data regarding Italy are missing or poor. We aim to provide detailed data on clubfoot incidence according to the Apulian Regional Registry on Congenital Malformations and to report current knowledge on clubfoot genetic factors.

METHODS

We extrapolated data from the Regional Registry of Congenital Malformations to evaluate incidence and prevalence of congenital clubfoot in Apulia, Italy over a period of four years (2015-2018). We also performed a narrative review focusing on genetic mutations leading to congenital clubfoot.

RESULTS

Over the period from 2015 to 2018 in Apulia, Italy, 124,017 births were recorded and 209 cases of clubfoot were found, accounting for an incidence rate of 1.7/1,000 and a prevalence rate of 1.6/1,000. Six families of genes have been reported to have an etiopathogenetic role on congenital clubfoot.

CONCLUSIONS

Incidence and prevalence of congenital clubfoot in Apulia, Italy, are comparable with those reported in the other Italian regions but higher than those reported in previous studies from Europe. Genetic studies to better classify congenital clubfoot in either syndromic or isolated forms are desirable.

Genetic Role in Recurrence of Idiopathic CTEV: A Systematic Review

Background

Congenital Talipes Equinovarus (CTEV) is a multitude of deformities involving equinus, varus, adductus, and cavus deformities. Clubfoot affects 1 in every 1000 infants born worldwide, with various incidences according to geographical areas. It has been previously hypothesized that the possible genetic role in Idiopathic CTEV (ICTEV) might have a treatment-resistant phenotype. However, the genetic involvement in recurrent ICTEV cases is yet to be determined.

Aim

To systematically review existing literature regarding the discovery of genetic involvement in recurrent ICTEV to date to further understand the etiology of relapse.

Methods

A comprehensive search was performed on medical databases, and the review was conducted according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) 2020 guidelines. A comprehensive search was performed on several medical databases: PubMed (MEDLINE), Scopus, the Cochrane Library, and European PMC on May 10, 2022. We included studies reporting patients with recurring idiopathic CTEV or CTEV of unknown cause after treatment, reporting whole-genetic sequencing, whole-exome sequencing, Polymerase Chain Reaction, or Western blot analysis as methods of genetic analysis (intervention) and providing results of idiopathic CTEV genetic involvement. Non-English studies, literature reviews, and irrelevant articles were excluded. Quality and risk of bias assessments were performed using Newcastle-Ottawa Quality Assessment Scale for non-randomized studies where appropriate. The authors discussed data extracted with the primary outcome of gene(s) frequency being reported of their involvement in recurrent ICTEV cases.

Results

Three pieces of literature were included in this review. Two studies analyzed the genetic involvement in CTEV occurrence, while one analyzed the protein types found.

Discussion

With included studies of less than five, we could not perform other forms of analysis apart from qualitatively.

Conclusion

The rarity of literature exploring the genetic etiology of recurrent ICTEV cases has been reflected in this systematic review, giving opportunities for future research.

The molecular genetics of human appendicular skeleton

Disorders that result from de-arrangement of growth, development and/or differentiation of the appendages (limbs and digit) are collectively called as inherited abnormalities of human appendicular skeleton. The bones of appendicular skeleton have central role in locomotion and movement. The different types of appendicular skeletal abnormalities are well described in the report of "Nosology and Classification of Genetic skeletal disorders: 2019 Revision". In the current article, we intend to present the embryology, developmental pathways, disorders and the molecular genetics of the appendicular skeletal malformations. We mainly focused on the polydactyly, syndactyly, brachydactyly, split-hand-foot malformation and clubfoot disorders. To our knowledge, only nine genes of polydactyly, five genes of split-hand-foot malformation, nine genes for syndactyly, eight genes for brachydactyly and only single gene for clubfoot have been identified to be involved in disease pathophysiology. The current molecular genetic data will help life sciences researchers working on the rare skeletal disorders. Moreover, the aim of present systematic review is to gather the published knowledge on molecular genetics of appendicular skeleton, which would help in genetic counseling and molecular diagnosis.

Comparative study of the outcome of McKay surgery with and without pin in clubfoot patients

BACKGROUND

Clubfoot is one of the most common foot deformities in children. Surgical treatment is the only choice for patients who have failed conservative treatment. To the best of our knowledge, no studies have been done to compare the McKay surgery with a pin versus without a pin. Our study aimed to compare the outcomes of McKay surgery with and without pins in clubfoot patients.

METHOD

This study is an analytical study. The sample size included patients referred to Imam Reza Hospital from 2016 to 2018. Children who did not respond to plaster therapy were under McKay surgery. In this study, patients were divided into two groups of 50 patients. In the first group, after ligament release and tendon extension, a pin was used to maintain the direction of the talonavicular joint. In the second group, no pin was used. Every six months, radiographs were taken of the patients to monitor their progress. After collecting the study data, they were entered into SPSS software (version 25, IBM Corporation, Armonk, NY) and analyzed.

RESULT

The mean age of patients was 5.36±2.07 months. Of these, 79 were boys and 21 girls, most of the subjects were aged 4-6 months, and 24% had unilateral one-way clubs. The severity of the disease was 7 feet in grade 2 (moderate) and 93 feet in grade 3 (severe). There was a significant relationship between age, outcome and type of complications with surgical type.

CONCLUSION

Finally, it can be concluded that McKay surgery (both with and without a pin) is exceptionally effective at treating clubfoot.

Eight-year Review of a Clubfoot Treatment Program in Pakistan With Assessment of Outcomes Using the Ponseti Technique: A Retrospective Study of 988 Patients (1,458 Clubfeet) Aged 0 to 5 Years at Enrollment

To conduct an 8-year retrospective review of a clubfoot treatment program using the Ponseti technique with close monitoring of outcomes.

Two-year retrospective cohort results on use of a dynamic unilateral brace for treatment of clubfoot: Can compliance and prevention of recurrence both be achieved?

Objectives

The Ponseti method has led to vast improvements in outcomes for infants born with clubfoot deformity, but challenges with compliance during the bracing phase of the protocol remain. Unilateral braces promise higher compliance but often have led to unacceptably high recurrence.

Methods

We have developed a novel unilateral brace for clubfoot deformity that strategically applies patient-specific, anatomically-targeted forces to the lower limb to maintain correction. We retrospectively reviewed the cases of 26 patients with minimum follow-up of 24 months. The data were analyzed for recurrence rates, caregiver-reported compliance, and differences in Pirani score, dorsiflexion, abduction, hindfoot eversion, and resting rotation between initial and final follow-up.

Results

Most patients (N = 23, 88%) were compliant with the bracing protocol. Two patients showed recurrence of deformity (8%). There were statistically significant improvements in Pirani score, dorsiflexion, abduction, hindfoot eversion, and resting external rotation. A subset of patients with sub-optimal correction at baseline showed improvement in all parameters across the course of bracing.

Conclusions

This novel unilateral brace for maintenance of clubfoot correction after Ponseti treatment demonstrates rates of recurrence rates and caregiver-reported compliance at 2 years of follow up that are comparable to outcomes with traditional bilateral foot abduction orthoses.

Developments in pediatrics in 2020: choices in allergy, autoinflammatory disorders, critical care, endocrinology, genetics, infectious diseases, microbiota, neonatology, neurology, nutrition, ortopedics, respiratory tract illnesses and rheumatology

In this article, we describe the advances in the field of pediatrics that have been published in the Italian Journal of Pediatrics in 2020. We report progresses in understanding allergy, autoinflammatory disorders, critical care, endocrinology, genetics, infectious diseases, microbiota, neonatology, neurology, nutrition, orthopedics, respiratory tract illnesses, rheumatology in childhood.

Management issues of congenital talipes equinovarus in the neonatal intensive care unit: A systematic review

BACKGROUND

The Ponseti method is the standard of care for managing idiopathic congenital talipes equinovarus (clubfoot) in the outpatient setting, but there are no clinical guidelines for inpatient treatment. Children in the neonatal intensive care unit (NICU) with clubfoot often delay treatment initiation due to medical reasons.

METHODS

We systematically reviewed literature related to the treatment of clubfoot in the NICU, non-idiopathic clubfoot, and older infants, as well as barriers to care.

RESULTS

In a mixed NICU population of syndromic and idiopathic clubfoot, the Ponseti method has good functional outcomes with minimal interference with medical management. The Ponseti method has good functional outcomes with reduced need for extensive surgical procedures in non-idiopathic clubfoot and idiopathic clubfoot with delayed presentation (under one year of age).

CONCLUSIONS

It is possible to begin Ponseti treatment in the NICU without compromising medical management. It is not clear if this confers an advantage over waiting for outpatient casting.

Outcomes of Clubfoot Treated With Casting in Ghana

OBJECTIVE

Idiopathic clubfoot deformity is a condition in pediatric orthopedics with a prevalence of 1 in 1000. This study reports the outcomes of clubfoot treatment in Ghana.

METHODS

The study was Institutional Review Board (IRB) approved. Patients with clubfoot were treated by the Ponseti method including weekly casting, Achilles tendon lengthening (TAL), and prolonged bracing. Data points collected included: extent of clubfoot, age, relapse, tenotomy prevalence, and number of casts.

RESULTS

Out of 1,634 patients, 72.4% were less than a year of age at the time of the first cast, 82.6% had more than eight casts prior to bracing, and 74.0% had a percutaneous Achilles tenotomy prior to the final cast placement. Only 1.2% of patients suffered a relapse.

CONCLUSION

 In Ghana, delays in seeking in treatment are common. Optimal results for the Ponseti treatment occur in children who present prior to the age of one. In the current study, 27.6% of children delayed treatment until after one. We recommend a community advocacy program to educate leaders and medical personnel about the Ponseti method. Despite a delay of treatment in 25% of the patients, there was only a 1.2% relapse rate. We recommend the Ponseti method in Ghana for children of all ages.

Co-occurrence of orofacial clefts and clubfoot phenotypes in a sub-Saharan African cohort: Whole-exome sequencing implicates multiple syndromes and genes

Background

Orofacial clefts (OFCs) are congenital malformations of the face and palate, with an incidence of 1 per 700 live births. Clubfoot or congenital talipes equinovarus (CTEV) is a three‐dimensional abnormality of the leg, ankle, and feet that leads to the anomalous positioning of foot and ankle joints and has an incidence of 1 per 1000 live births. OFCs and CTEV may occur together or separately in certain genetic syndromes in addition to other congenital abnormalities. Here, we sought to decipher the genetic etiology of OFC and CTEV that occurred together in six probands.

Methods

At the time of recruitment, the most clinically obvious congenital anomalies in these individuals were the OFC and CTEV. We carried out whole‐exome sequencing (WES) on DNA samples from probands and available parents employing the Agilent SureSelect XT kit and Illumina HiSeq2500 platform, followed by bioinformatics analyses. WES variants were validated by clinical Sanger Sequencing.

Results

Of the six probands, we observed probable pathogenic genetic variants in four. In three probands with probable pathogenic genetic variants, each individual had variants in three different genes, whereas one proband had probable pathogenic variant in just one gene. In one proband, we observed variants in DIS3L2, a gene associated with Perlman syndrome. A second proband had variants in EPG5 (associated with Vici Syndrome), BARX1 and MKI67, while another proband had potentially etiologic variants in FRAS1 (associated with Fraser Syndrome 1), TCOF1 (associated with Treacher Collins Syndrome 1) and MKI67. The last proband had variants in FRAS1, PRDM16 (associated with Cardiomyopathy, dilated, 1LL/Left ventricular noncompaction 8) and CHD7 (associated with CHARGE syndrome/Hypogonadotropic hypogonadism 5 with or without anosmia).

Conclusion

Our results suggest that clubfoot and OFCs are two congenital abnormalities that can co‐occur in certain individuals with varying genetic causes and expressivity, warranting the need for deep phenotyping.

Assessment of the talar deformity and alignment in congenital clubfoot using three-dimensional MRI after Ponseti method

BACKGROUND

Ponseti method have been widely accepted as the initial treatment of congenital idiopathic clubfoot because its excellent primary result. On the other hand, relapses after Ponseti method are not uncommon and the cause of relapses have not been fully elucidated. We investigated detailed morphology and alignment of tarsal bones in clubfoot after Ponseti method using three-dimensional MRI analysis.

METHODS

We performed MRI with 10 patients of unilateral clubfoot at three months after Achilles tenotomy. Based on the MRI volume data, we reconstructed three-dimensional bone surface model using the marching cubes method. We evaluated the volume of the talus and navicular bone, medial and planter deviation of the talar head and neck, medial deviation of the navicular bone, and internal rotation angle of the distal tibiofibular joint.

RESULTS

In clubfoot, the volume of talus and navicular bone were significantly smaller compared with the contralateral side. Deviation of the talar head and neck varied from medially to almost the same as that on the contralateral side. The degree of deformity of the talus and alignment of the navicular bone and distal tibiofibular joint showed correlations.

CONCLUSIONS

Patients with the medial deviated talar neck might have the alignment change of navicular bone and distal tibiofibular joint. Deformity of talar neck might to be compensated by talonavicular joint and distal tibiofibular joint through the manipulation of Ponseti method.

Rare and de novo duplications containing SHOX in clubfoot

Introduction

Congenital clubfoot is a common birth defect that affects at least 0.1% of all births. Nearly 25% cases are familial and the remaining are sporadic in inheritance. Copy number variants (CNVs) involving transcriptional regulators of limb development, including PITX1 and TBX4, have previously been shown to cause familial clubfoot, but much of the heritability remains unexplained.

Methods

Exome sequence data from 816 unrelated clubfoot cases and 2645 in-house controls were analysed using coverage data to identify rare CNVs. The precise size and location of duplications were then determined using high-density Affymetrix Cytoscan chromosomal microarray (CMA). Segregation in families and de novo status were determined using qantitative PCR.

Results

Chromosome Xp22.33 duplications involving SHOX were identified in 1.1% of cases (9/816) compared with 0.07% of in-house controls (2/2645) (p=7.98×10⁻⁵, OR=14.57) and 0.27% (38/13592) of Atherosclerosis Risk in Communities/the Wellcome Trust Case Control Consortium 2 controls (p=0.001, OR=3.97). CMA validation confirmed an overlapping 180.28 kb duplicated region that included SHOX exons as well as downstream non-coding regions. In four of six sporadic cases where DNA was available for unaffected parents, the duplication was de novo. The probability of four de novo mutations in SHOX by chance in a cohort of 450 sporadic clubfoot cases is 5.4×10^–10.

Conclusions

Microduplications of the pseudoautosomal chromosome Xp22.33 region (PAR1) containing SHOX and downstream enhancer elements occur in ~1% of patients with clubfoot. SHOX and regulatory regions have previously been implicated in skeletal dysplasia as well as idiopathic short stature, but have not yet been reported in clubfoot. SHOX duplications likely contribute to clubfoot pathogenesis by altering early limb development.

The genetics of isolated and syndromic clubfoot

PURPOSE

Congenital clubfoot is a serious birth defect that affects nearly 0.1% of all births. Though there is strong evidence for a genetic basis of isolated clubfoot, aside from a handful of associations, much of the heritability remains unexplained.

METHODS

By systematically examining the genes involved in syndromic clubfoot, we may find new candidate genes and pathways to investigate in isolated clubfoot.

RESULTS

In addition to the expected enrichment of extracellular matrix and transforming growth factor beta (TGF-β) signalling genes, we find many genes involved in syndromic clubfoot encode peroxisomal matrix proteins, as well as enzymes necessary for sulfation of proteoglycans, an important part of connective tissue. Further, the association of Filamin B with isolated clubfoot as well as syndromic clubfoot is an encouraging finding.

CONCLUSION

We should examine these categories for enrichment in isolated clubfoot patients to increase our understanding of the underlying biology and pathophysiology of this deformity. Understanding the spectrum of syndromes that have clubfoot as a feature enables a better understanding of the underlying pathophysiology of the disorder and directs future genetic screening efforts toward certain genes and genetic pathways.

LEVEL OF EVIDENCE

V.

The congenital clubfoot - immunohistological analysis of the extracellular matrix

Purpose

Congenital clubfoot is one of the most common limb disorders in humans and its etiology is still unclear. In order to better understand the pathogenesis of patients with primary clubfoot, we examined whether there are quantitative changes in the extracellular matrix (ECM; based on common interstitial collagens [C] like CI and CIII, microfilamentous collagens like CVI, noncollagenous proteins like undulin, and enzymes like matrixmetalloproteinase [MMP]-2 and tissue inhibitor of matrixmetalloproteinase [TIMP]-2 that are known to play a role in fibrogenesis and fibrolysis) of muscles involved in the foot deformity of patients with primary clubfoot corresponding to fibrosis.

Patients and methods

Thirty patients (age ranging from 4 months to 5 years and 7 months) with primary clubfoot were examined (23 male and 7 female patients), among whom 18 patients were affected on one side and 12 affected on both sides. Twenty-five biopsies were taken during the first operative foot correction (Crawford-McKay) and 5 in the context of relapses. Muscle biopsies were taken from the muscles involved in the defect (Musculus [M.] gastrocnemius and M. tibialis anterior) and from the M. vastus lateralis of the M. quadriceps femoris, which were treated as healthy comparison muscles. Quantitative analysis of the components of the ECM was performed using a computer-assisted fibrosis measurement of the immunohistochemically processed tissue samples.

Results

We found higher values for M. gastrocnemius for CI, CIII, CVI and undulin in comparison with M. vastus lateralis. However, values for TIMP-2 were reduced. We found no significant differences for the components of M. tibialis anterior and M. vastus lateralis. There were no quantitative differences between male and female or between patients affected on one side and both sides. In patients who underwent relapse surgery, CI, CIII, CVI, and undulin of the gastrocnemius were significantly higher, while TIMP-2 was significantly lower.

Conclusion

In the present study, we found manifest fibrosis in gastrocnemius due to quantitative changes in the ECM. In contrast to other studies, we found increasing fibrosis not just in contracted tissues but also in the muscle itself. Further studies are needed to clarify whether these changes are primarily responsible for the malfunction or whether they occur secondarily in the consequence of the dysfunction.

Genetics of clubfoot; recent progress and future perspectives

Clubfoot or talipes equinovarus (TEV) is an inborn three-dimensional deformity of leg, ankle and foot. It results from structural defects of several tissues of foot and lower leg leading to abnormal positioning of foot and ankle joints. TEV can lead to long-lasting functional disability, malformation and discomfort if left untreated. Substantial progress has been achieved in the management and diagnosis of limb defects; however, not much is known about the molecular players and signalling pathways underlying TEV disorder. The homeostasis and development of the limb depends on the complex interactions between the lateral plate mesoderm cells and outer ectoderm. These complex interactions include HOX signalling and PITX1-TBX4 pathways. The susceptibility to develop TEV is determined by a number of environmental and genetic factors, although the nature and level of interplay between them remains unclear. Familial occurrence and inter and intra phenotypic variability of TEV is well documented. Variants in genes that code for contractile proteins of skeletal myofibers might play a role in the aetiology of TEV but, to date, no strong candidate genes conferring increased risk have emerged, although variants in TBX4, PITX1, HOXA, HOXC and HOXD clusters genes, NAT2 and others have been shown to be associated with TEV. The mechanisms by which variants in these genes confer risk and the nature of the physical and genetic interaction between them remains to be determined. Elucidation of genetic players and cellular pathways underlying TEV will certainly increase our understanding of the pathophysiology of this deformity.