Soft-Tissue Abnormalities Associated with Treatment-Resistant and Treatment-Responsive Clubfoot: Findings of MRI Analysis

Comparison of kinematics and pedobarography findings between the unaffected foot of patients with unilateral clubfoot and controls

PURPOSE

Idiopathic clubfoot (ICF) involves structural abnormalities in the lower extremities. Approximately half of patients have unilateral ICF, which could be due to differences in limb formation. The contralateral unaffected foot may have subclinical ICF. The objectives were to compare ankle and foot kinematics and pedobarography findings between the unaffected foot of patients with unilateral ICF and controls.

METHODS

Eleven children with unilateral ICF (11 unaffected feet, 11.7 ± 3.8 years) and 15 age-matched controls (30 control feet, 11.1 ± 3.0 years) were enroled. Five complete gait trials were performed. Data were collected using ten cameras and a two m long Footscan system and compared between groups using the Wilcoxon rank sum test.

RESULTS

All children with ICF underwent the selective soft tissue release procedure. The unaffected feet showed limited ranges in inversion-eversion and dorsiflexion-plantar flexion on kinematic analysis. There was a delay in landing time in all regions of the foot during heel rise and propulsion. The peak time was achieved significantly later in the unaffected feet compared to the controls. Although plantar pressure parameters were comparable, unaffected feet showed a larger contact area in the midfoot region.

CONCLUSIONS

Gait data on the unaffected foot in unilateral ICF patients do not correspond to those of controls despite an indistinguishable clinical appearance. This could be due to the effect of treatment, the process of foot development, or a combination. The relationship between genetics and gait deviation in patients with unilateral ICF needs further evaluation. The unaffected foot should receive similar attention during follow-up.

Initial clubfoot treatment in Sweden from 2016 to 2019: A national register study

BACKGROUND

This study aimed to describe the initial treatment of clubfoot deformity in Sweden using a national cohort. Secondarily we aimed to analyse the results of the initial treatment in relation to foot severity and additional diseases.

METHODS

A national register, the Swedish Pediatric Orthopedic Quality Register, was used to extract data on children born with clubfoot in 2016-2019. Children with a registered evaluation after initial treatment were included. Data on deformity severity (Pirani score), casting treatment, and achillotenotomy were extracted. For children with bilateral clubfeet, one foot was included in the analysis.

RESULTS

A total of 565 children were included in the analysis. Of these, 73% were boys and 47% had bilateral clubfeet. Children with isolated clubfoot required a median of six casts to correct the deformity, while children with non-isolated clubfoot needed a median of eight casts. Seventy-seven percent underwent an achillotenotomy. Residual deformities of 0.5 or above (often soft-tissue issues) according to the Pirani score were noted in 23% (isolated clubfoot) and 61% (non-isolated clubfoot) after initial treatment.

CONCLUSIONS

We have described the initial clubfoot treatment of children born with isolated or non-isolated clubfoot in Sweden based on data from a national register. The initial treatment was performed to a large extent according to the Ponseti method and international recommendations. Moreover, we discuss the usefulness of the Pirani score in classifying clubfoot deformity after treatment.

Duration and outcome of orthotic treatment in children with clubfoot - a four-year follow-up national register study of Swedish children born between 2015 and 2017

BACKGROUND

The Ponseti method for treating clubfoot consists of initial treatment with serial casting accompanied by achillotenotomy if needed, followed by the maintenance phase including treatment with a foot abduction orthosis (FAO) for at least four years. This study aimed to examine the duration, course, and outcome of orthotic treatment in children with clubfoot.

METHODS

321 children with clubfoot, born between 2015 and 2017, registered in the Swedish Pediatric Orthopedic Quality Register (SPOQ), were included in this prospective cohort study. Data on deformity characteristics and orthotic treatment were extracted. For children with bilateral clubfoot, one foot was included in the analysis.

RESULTS

Of the 288 children with isolated clubfoot, 274 children (95.5%) were prescribed an FAO, and 100 children (35%) changed orthosis type before 4 years of age. Of the 33 children with non-isolated clubfoot, 25 children (76%) were prescribed an FAO, and 21 children (64%) changed orthosis type before 4 years of age. 220 children with isolated clubfoot (76%), and 28 children with non-isolated clubfoot (84%) continued orthotic treatment until 4 years of age or longer. Among children with isolated clubfoot, children ending orthotic treatment before 4 years of age (n = 63) had lower Pirani scores at birth compared to children ending orthotic treatment at/after 4 years of age (n = 219) (p = 0.01). It was more common to change orthosis type among children ending orthotic treatment before 4 years of age (p = 0.031).

CONCLUSIONS

The majority of children with clubfoot in Sweden are treated with an FAO during the maintenance phase. The proportion of children changing orthosis type was significantly greater and the Pirani score at diagnosis was lower significantly among children ending orthotic treatment before 4 years of age. Long-term follow-up studies are warranted to fully understand how to optimize, and individualize, orthotic treatment with respect to foot involvement and severity of deformity.

LEVEL OF EVIDENCE

II.

Clinical Characteristics and Whole Exome Sequencing Analysis in Serbian Cases of Clubfoot Deformity-Single Center Study

BACKGROUND

Recognized as one of the most serious musculoskeletal deformities, occurring in 1-2 per 1000 newborns, 80% of clubfeet are idiopathic while 20% present with associated malformations. The etiopathogenesis of clubfoot is described as multifactorial, including both genetic and environmental risk factors. The aim of this study was to analyze possible genetic causes of isolated and syndromic clubfoot in Serbian children, as well as to correlate clinical and genetic characteristics that would provide insight into clubfoot etiopathogenesis and possibly contribute to global knowledge about clinical features of different genetically defined disorders.

METHODS

We evaluated 50 randomly selected, eligible children with clubfoot aged 3 to 16 years that were initially hospitalized and treated at University Children's Hospital between November 2006 and November 2022. The tested parameters were gender, age, dominant foot, affected foot, degree of deformity, treatment, neuromuscular disorders, positive family history, and maternal smoking. According to the presence of defined genetic mutation/s by whole exome sequencing (WES), patients were separated into two groups: positive (with genetic mutation/s) and negative (without genetic mutation/s).

RESULTS

Seven patients were found to be positive, i.e., with genetic mutation/s. A statistically significant difference between categorical variables was found for families with a history of clubfoot, where more than half (57.14%) of patients with confirmed genetic mutation/s also had a family history of genetic mutation/s (p = 0.023).

CONCLUSIONS

The results from this study further expand the genetic epidemiology of clubfoot. This study contributes to the establishment of genetic diagnostic strategies in pediatric patients with this condition, which can lead to more efficient genetic diagnosis.

A prospective study on the role of foot evertor muscle activity in recurrence of clubfoot

BACKGROUND

Even after corrective casting and bracing, clubfoot recurrence is challenging throughout childhood, with around 14-40 % recurrence rates. Most of the literature on recurrence was attributed to various factors, and minimal research was conducted to know the role of foot evertor muscle activity and its stimulation benefits. This study aimed to assess the role of foot evertor muscle activity in idiopathic congenital clubfoot recurrence by using clinical, sonographic, and electromyographic parameters.

METHODS

A prospective cohort study was conducted at our tertiary care hospital from 2020 to 2022. The patient's demographic data, Pirani, Dimeglio, Clinical Evertor Muscle Activity scores, sonographic cross-sectional areas of leg muscle, and evertor motor activity using surface electromyography were recorded in adherence to the pre-defined intervals.

RESULTS

In total, 51 patients (51 feet) were included in the study, and the overall recurrence rate was 27.5 % (14/51). In this study, around 47 % (24/51) of children had mild or poor clinical evertor activity; among them, 58 % (14/24) children had a recurrence, and the insufficient clinical evertor activity and recurrence were strongly correlated (p = 0.01). Evertor muscle cross-sectional area ratio, motor unit potentials, and recruitment were comparatively less in the recurred group; however, only the cross-sectional area ratio was statistically significant (p = 0.02).

CONCLUSION

Early detection of evertor muscle weakness can help to individualize the treatment plans by predicting recurrence. Therefore, it should be included in routine clinical evaluations. Further research is required to determine the advantages of evertor muscle-strengthening activities in preventing idiopathic clubfoot deformity.

LEVEL OF CLINICAL EVIDENCE

A prospective cohort study, Level of evidence-II.

Anatomical Structures Responsible for CTEV Relapse after Ponseti Treatment

Relapse of deformity after a successful Ponseti treatment remains a problem for the management of clubfoot. An untreated varus heel position and restricted dorsal flexion of the ankle are the main features of recurrences. We analyze the anatomical structures responsible for these recurrences. Materials and methods: During 5 years, 52 children with CTEV (Congenital Talipes Equino Varus) were treated with casts according to the Ponseti method, with a mean number of 7 casts. Closed percutaneous tenotomy was performed in 28 infants. Children were followed monthly and treated with the continuous use of a molded cast. We had 9 children with relapsed clubfeet. During the standing and walking phase, they had a fixed deformity with a varus position of the heel and dorsal flexion of the ankle <10 d. They were surgically treated with the posterolateral approach. Results: In all patients, we found a severe thickening of the paratenon of the Achilles in the medial side, with adhesions with the subcutaneous tissue. The achilles after the previous tenotomy was completely regenerated. The achilles was medially displaced. Conclusions: A severe thickening of the paratenon of the achilles and adhesions with the subcutaneous tissue are anatomical structures in fixed relapsed cases of clubfoot. We treated our patients with an appropriate surgical release.

Lateral Cuneiform Ossification and Tibialis Anterior Tendon Width in Children Ages 3 to 6: Implications for Interference Screw Fixation of Tibialis Anterior Tendon Transfers in Children

BACKGROUND

While the transfer of the tibialis anterior tendon (TAT) to the lateral cuneiform (LC) following serial casting has been used for nearly 60 years to treat relapsed clubfoot deformity, modern methods of tendon fixation remain largely unstudied. Interference screw fixation represents an alternative strategy that obviates concerns of plantar foot skin pressure-induced necrosis and proper tendon tensioning associated with button suspensory fixation. A better understanding of LC morphology in young children is a necessary first step in assessing the viability of this fixation technique. Therefore, the purpose of this investigation is to define LC morphology and TAT width in children aged 3 to 6 years.

METHODS

A retrospective radiographic review of 40 healthy pediatric feet aged 3 to 6 years who had either magnetic resonance imaging or computed tomography scans was performed at a single pediatric hospital. The length, width, and height of only the ossified portion of the LC were measured digitally using sagittal, coronal, and axial imaging. In addition, the maximal cross-sectional diameter of the TAT was measured at the level of the tibiotalar joint.

RESULTS

The average ossified LC width ranged from 8.5 mm in the 3-year-old cohort to 10.3 mm in 6-year-old children. Analysis of variance testing revealed no statistically significant difference in width between age groups. Average ossified LC length ranged from 13.5 mm in the 3-year-old cohort to 18.3 mm in 6-year-old children with statistically significant increases in age groups separated by 2 or more years. Significant differences in LC height, volume, and TAT diameter were demonstrated after analysis of variance testing. The TAT to ossified LC width ratio ranged from 44% to 53% across age groups.

CONCLUSIONS

The dimensions of the LC ossification center are large enough to allow interference screw fixation in children 3 to 6 years of age. Further studies are needed to investigate interference screw fixation performance in the pediatric clubfoot population.

LEVEL OF EVIDENCE

Level IV.

Muscle-tendon properties and functional gait outcomes in clubfoot patients with and without a relapse compared to typically developing children

BACKGROUND

Altered muscle-tendon properties in clubfoot patients could play a role in the occurrence of a relapse and negatively affect physical functioning. However, there is a lack of literature about muscle-tendon properties of clubfoot relapse patients.

RESEARCH QUESTION

The aim of this study was to determine whether the muscle architecture of the medial gastrocnemius and the morphology of the Achilles tendon differ between typically developing children (TDC) and clubfoot patients with and without a relapse clubfoot and to determine the relationships between morphological and functional gait outcomes.

METHODS

A cross-sectional study was carried out in clubfoot patients treated according to the Ponseti method and TDC aged 4-8 years. A division between clubfoot patients with and without a relapse was made. Fifteen clubfoot patients, 10 clubfoot relapse patients and 19 TDC were included in the study. Morphologic properties of the medial head of the Gastrocnemius muscle and Achilles tendon were assessed by ultrasonography. Functional gait outcomes were assessed using three-dimensional gait analysis. Mean group differences were analysed with ANOVA and non-parametric alternatives. Relationships between functional and morphologic parameters were determined for all clubfoot patients together and for TDC with Spearman's rank correlation.

RESULTS

Morphological and functional gait parameters did not differ between clubfoot patients with and without a relapse, with exception of lower maximal dorsiflexor moment in clubfoot relapse patients. Compared to TDC, clubfoot and relapse patients did show lower functional gait outcomes, as well as shorter and more pennate muscles with a longer Achilles tendon. In all clubfoot patients, this longer relative tendon was related to higher ankle power and plantarflexor moment.

SIGNIFICANCE

In clubfoot and relapse patients, abnormalities in morphology did not always relate to worse functional gait outcomes. Understanding these relationships in all clubfoot patients may improve the knowledge about clubfoot and aid future treatment planning.

Congenital Clubfoot - Is the Ponseti Method the Definitive Solution?

Congenital clubfoot is one of the most common deformities at birth. The inadequacy or absence of treatment causes serious limitations for people with this condition. The initial treatment using the Ponseti method ensures functional results superior to other treatment modalities previously proposed. However, recurrences and neglected feet are still a challenge today. An understanding of the pathophysiology of the disease, as well as of the anatomy and local biomechanics and a thorough clinical and radiological evaluation of patients are essential to understanding the limits of the method and choosing the best treatment.

Muscle volume evaluation using 3DCT for congenital clubfoot

Background

In congenital clubfoot, the lower leg is very thin and the calf muscles are hypoplasic. However, there are few studies reporting real muscle volume.

Purpose

The purpose of this study is to assay the muscle volume in congenital clubfoot using 3DCT and to quantify the degree of the hypoplasia.

Material and methods

From January 2015 to December 2016, nine consecutive patients, seven male and two female, with unilateral congenital clubfeet were recruited for CT scans. Axial transverse sectional CT scans were acquired from the delineation of the fibular head to the tibial plafond. From the data, we rendered the entire muscle in 3D for muscle volume assay, and further segmented the posterior musculature for comparison between the normal and affected sides.

Results

The whole muscle volume on the normal side was 291.23 cm³ (181.23–593.49) and that on the affected side was 225.08 cm³ (120.71–429.08), for an affected side to normal side ratio of 0.79 (0.72–0.9), which was significantly smaller (p < .01). Posterior muscle volume on the normal side was 175.81 cm³ (103.72–376.32) and that on the affected side was 106.52 cm³ (58.3–188.39). The ratio of posterior muscle to whole muscle on the normal side was 0.62 (0.46–0.75), and that on the affected side was 0.48 (0.4–0.55), such that the affected side was significantly smaller (p < .01)

Conclusion

This study contributes quantitative data supporting the longstanding observations that the posterior calf muscles are significantly smaller on the affected side compared to the normal side in congenital clubfoot, and further underscores the importance of the extending the excursion of these muscles.

Epidemiology of clubfoot in Sweden from 2016 to 2019: A national register study

BACKGROUND

This study aimed to estimate the birth prevalence of children born with isolated or non-isolated clubfoot in Sweden using a national clubfoot register. Secondarily we aimed to describe the clubfoot population with respect to sex, laterality, severity of deformity, comorbidity and geographic location.

METHODS

A national register, the Swedish Pediatric Orthopedic Quality register, was used to extract data on newborn children with clubfoot. To calculate the birth prevalence of children with isolated or non-isolated clubfoot between 1st of January 2016 and 31st of December 2019, we used official reports of the total number of Swedish live births from the Swedish Board of Statistics. The Pirani score and predefined signs of atypical clubfoot were used to classify clubfoot severity at birth.

RESULTS

In total 612 children with clubfoot were identified. Of these, 564 were children with isolated clubfoot, generating a birth prevalence of 1.24/1000 live births (95% confidence interval 1.15-1.35). About 8% were children with non-isolated clubfoot, increasing the birth prevalence to 1.35/1000 live births (95% confidence interval 1.25-1.46). Of the children with isolated clubfoot, 74% were boys and 47% had bilateral involvement. The children with non-isolated clubfoot had more severe foot deformities at birth and a greater proportion of clubfeet with atypical signs compared with children with isolated clubfoot.

CONCLUSION

We have established the birth prevalence of children born with isolated or non-isolated clubfoot in Sweden based on data from a national register. Moreover, we have estimated the number of children born with atypical clubfeet in instances of both isolated and non-isolated clubfoot. These numbers may serve as a baseline for expected birth prevalence when planning clubfoot treatment and when evaluating time trends of children born with clubfoot.

Concomitant Talocalcaneal Coalition as a Risk Factor for Early Relapse Following Ponseti Treatment of Idiopathic Clubfoot

Concomitant talocalcaneal coalition (TCC) in idiopathic clubfeet is not well documented in the literature. The purpose of this study was to describe our experience with very early relapsing idiopathic clubfeet associated with TCC. Although cases have been successfully treated with the Ponseti casting method, all recurred within 2 months of removing the final cast. A single-centre cohort of twelve feet in eight patients treated by a single surgeon between 2006 and 2020 was investigated retrospectively. Recurred cavus with variable degrees of equinus was the earliest findings noted. TCC was incidentally detected during the open reduction of the earliest three feet in our series. Afterwards, ultrasonography was advised as a screening tool for detecting an associated anomaly; however, only the use of magnetic resonance imaging (MRI) was 100% accurate in diagnosing concurrent TCC. All coalitions were cartilaginous and the posterior facet was most commonly involved facet. The average age was 18 months for the coalition resection and open reduction of a dislocated talonavicular joint, and the average duration of follow-up was 52 months. None of the patients showed clinical signs of relapse at the latest follow-up. We recommend that an associated TCC should be considered in very early relapsing idiopathic clubfoot cases.

Development of foot length in children with congenital clubfoot up to 7 years of age: a prospective follow-up study

Background

Clubfeet are typically shorter than normal feet. This study aimed first to describe the development of foot length in a consecutive series of children with congenital clubfoot and second to relate foot length to development of relapse and motion quality.

Methods

Foot length was measured every 6 months in 72 consecutive children with congenital clubfoot (29 bilateral) aged from 2 to 7 years. The initial treatment was nonsurgical followed by standardized orthotic treatment. Foot length growth rate was calculated every half year. In children with unilateral clubfeet, the difference in foot length between the clubfoot and the contralateral foot was calculated. Motion quality was evaluated by the Clubfoot Assessment Protocol (CAP). Student’s t test, the Mann–Whitney U test and Spearman’s correlation were used for group comparisons. Bonferroni correction was used when multiple comparisons were performed.

Results

Clubfeet were smaller (P < 0.001) than reference feet at all ages but had a similar growth rate up to age 7. Unilateral clubfeet with greater difference in size compared with the contralateral foot at the first measurement, relapsed more frequently (P = 0.016) and correlated with poorer motion quality (r = 0.4; P = 0.011).

Conclusions

As previously reported, clubfeet were smaller than reference feet at all ages. The growth rate, however, was similar between clubfeet and reference feet. Children with unilateral clubfeet and greater foot length difference at 2 years of age had a higher tendency to relapse and poorer motion quality at 7 years of age, indicating that foot length could be used as a prognostic tool.

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.

Factors Related to Early Recurrence of Idiopathic Clubfoot Post the Ponseti Method

Introduction: Idiopathic clubfoot or congenital talipes equinovarus (CTEV) is managed by the Ponseti method worldwide; however, the recurrence of the deformity is a challenging problem. The purpose was to review the factors associated with early recurrence of CTEV post the Ponseti method. Materials and Methods: During 2011-2016, 34 infants with 52 CTEV, who underwent the Ponseti method and a minimum follow-up period of six months, were reviewed. Twenty-two infants (65%) were male, and 18 infants (53%) had bilateral CTEV. Recurrence of CTEV was defined as a reappearance of at least one of the four components of the deformity. The association between recurrence and factors, including age, gender, bilaterality, family geography, type of principal caregiver, severity at presentation, centre where the Ponseti method was initiated, compliance to foot abduction brace (FAB), practice of stretching exercise, type of FAB, and complications of casting, were evaluated using univariate logistic regression analysis. Results: The median age at initiation of the treatment was 3.4 (IQR; 2.1-12.6) weeks. A median of six (range; 3-12) casts were required. Tenotomy was performed in 32/34 (94%) of cases. Recurrence occurred in 14/52 feet (27%) at an average follow-up period of 2.3±1.1 years. Non-compliance to FAB protocol began at an average age of 11.2±6.5 months, and significantly increased the risk of recurrence during the weaning phase [OR (95%CI)=8.4 (1.2-92.4), p=0.03]. Other factors were not associated with the recurrence. Conclusion: Non-compliance to FAB occurred early during the treatment and related to a risk of recurrence of CTEV. Physicians should encourage the parents and/or guardians to follow the protocol to decrease the risk of recurrence.

Prognosticating Factors of Relapse in Clubfoot Management by Ponseti Method

BACKGROUND

It is challenging that some Ponseti method corrected clubfeet have a tendency to relapse. Controversies remain as to the implication of initial severity, representing the deformity degree, as well as number of casts needed, representing the treatment process, in predicting relapse. However, no study has been reported to take these 2 parameters into comprehensive consideration for outcome measurement. The purpose of this study is to investigate the correlation between the initial Pirani score and the number of casts required to correct the deformity in our series; to evaluate noncompliance as a risk factor of the deformity recurrence in Ponseti treatment; to test the validity and predictive value of a new proposed parameter, ratio of correction improvement (RCI) which is indicated by the initial Pirani scores divided by the number of casts.

METHODS

A total of 116 consecutive patients with 172 idiopathic clubfeet managed by Ponseti method were followed prospectively for a minimum of 2 years from the start of brace wearing. RCI value and the other clinical parameters were studied in relation to the risk of relapse by using multivariate logistic regression analysis modeling.

RESULTS

A positive correlation between the initial Pirani score and the number of casts required to correct the deformity was found in our series (r=0.67, P<0.01). There were 45 patients (39%) with brace noncompliance. The relapse rate was 49% (22/45). The odds ratio of relapse in noncompliant patients was 10 times more that in compliant patients (odds ratio=10.30 and 95% confidence interval, 2.69-39.42; P<0.01). The multivariate logistic regression analysis showed that there was significant association between relapse and RCI value. There were 42 patients (36%) with RCI value <1, among them, the relapse rate was 57% in 24 patients. The odds ratio of relapse in patients with RCI value <1 was 27 times more likely to relapse than those >1 (odds ratio=26.77 and 95% confidence interval, 5.70-125.72; P<0.01).

CONCLUSIONS

On the basis of the findings from our study, we propose the RCI to be a new parameter in predicting the risk of relapse in Ponseti method of clubfoot management. Early intervention is recommended to optimize the brace compliance particularly in case with lower RCI value.

LEVEL OF EVIDENCE

Level II-prognostic.

Functional Outcomes Following Treatment for Clubfoot: Ten-Year Follow-up

BACKGROUND

The purpose of this study was to assess function, at the age of 10 years, of children initially treated nonoperatively for clubfoot with either the Ponseti or French physiotherapy program and to compare outcomes in feet that had undergone only nonoperative treatment with those that required subsequent surgery.

METHODS

Gait analysis, isokinetic ankle strength, parent-reported outcomes, and daily step activity data were collected when patients who had been treated for idiopathic clubfoot reached the age of 10 years. Patients who had undergone only nonoperative treatment were compared with those who subsequently underwent extra-articular surgery or intra-articular surgery (posterior release or posteromedial release). The clubfoot groups were compared with age-matched controls.

RESULTS

Of 263 treated clubfeet in 175 patients, 148 had only been treated nonoperatively, 29 underwent extra-articular surgery, and 86 underwent intra-articular surgery (posterior release in 42 and posteromedial release in 44). Significant abnormalities were found in ankle kinetics and isokinetic ankle strength in the feet treated with intra-articular surgery compared with the nonoperatively treated feet (p < 0.017). Compared with controls (n = 40 feet), all groups showed reduced ankle plantar flexion during gait, resulting in a deficit of 9% to 14% for dynamic range of motion, 13% to 20% for ankle moment, and 13% to 23% for power (p < 0.013). Within the intra-articular group, feet that underwent posteromedial release had decreased plantar flexion strength (15%; p = 0.008), dorsiflexion strength (6%; p = 0.048), and parent-reported global function scores (p = 0.032) compared with the posterior release group. The patients with clubfoot took 10% fewer steps (p = 0.015) and had 11% less total ambulatory time (p = 0.001) than the controls.

CONCLUSIONS

Examination of patients when they had reached the age of 10 years showed better ankle power and isokinetic strength for clubfeet treated without surgery compared with those that underwent intra-articular surgery for residual deformity or recurrence. Compared with controls, both nonoperatively and surgically treated clubfeet had significant limitations in ankle plantar flexion resulting in decreased range of motion, moment, and power. Gastrocnemius-soleus complex strength was decreased after both nonoperative and surgical treatment of clubfeet. Although activity was diminished in the clubfoot population, no differences in function were perceived by the patients' parents.

LEVEL OF EVIDENCE

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

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.

The etiology of idiopathic congenital talipes equinovarus: a systematic review

BACKGROUND

Also known as clubfoot, idiopathic congenital talipes equinovarus (ICTEV) is the most common pediatric deformity and occurs in 1 in every 1000 live births. Even though it has been widely researched, the etiology of ICTEV remains poorly understood and is often described as being based on a multifactorial genesis. Genetic and environmental factors seem to have a major role in the development of this disease. Thus, the aim of this review is to analyze the available literature to document the current evidence on ICTEV etiology.

METHODS

The literature on ICTEV etiology was systematically reviewed using the following inclusion criteria: studies of any level of evidence, reporting clinical or preclinical results, published in the last 20 years (1998-2018), and dealing with the etiology of ICTEV.

RESULTS

A total of 48 articles were included. ICTEV etiology is still controversial. Several hypotheses have been researched, but none of them are decisive. Emerging evidence suggests a role of several pathways and gene families associated with limb development (HOX family; PITX1-TBX4), the apoptotic pathway (caspases), and muscle contractile protein (troponin and tropomyosin), but a major candidate gene has still not been identified. Strong recent evidence emerging from twin studies confirmed major roles of genetics and the environment in the disease pathogenesis.

CONCLUSIONS

The available literature on the etiology of ICTEV presents major limitations in terms of great heterogeneity and a lack of high-profile studies. Although many studies focus on the genetic background of the disease, there is lack of consensus on one or multiple targets. Genetics and smoking seem to be strongly associated with ICTEV etiology, but more studies are needed to understand the complex and multifactorial genesis of this common congenital lower-limb disease.

The 2017 ABJS Nicolas Andry Award: Advancing Personalized Medicine for Clubfoot Through Translational Research

BACKGROUND

Clubfoot is one of the most common pediatric orthopaedic disorders. While the Ponseti method has revolutionized clubfoot treatment, it is not effective for all patients. When the Ponseti method does not correct the foot, patients are at risk for lifelong disability and may require more-extensive surgery.

QUESTIONS/PURPOSES

(1) What genetic and morphologic abnormalities contribute to the development of clubfoot? (2) How can this information be used to devise personalized treatment paradigms for patients with clubfoot?

METHODS

Human gene sequencing, molecular genetic engineering of mouse models of clubfoot, MRI of clubfoot, and development of new treatment methods all have been used by our group to understand the biological basis and improve therapy for this group of disorders.

RESULTS

We gained new insight into clubfoot pathogenesis from our discovery that mutations in the PITX1-TBX4-HOXC transcriptional pathway cause familial clubfoot and vertical talus in a small number of families, with the unique lower limb expression of these genes providing an explanation for the lack of upper extremity involvement in these disorders. MRI studies revealed corresponding morphologic abnormalities, including hypomorphic muscle, bone, and vasculature, that are not only associated with these gene mutations, but also are biomarkers for treatment-resistant clubfoot.

CONCLUSIONS

Based on an understanding of the underlying biology, we improved treatment methods for neglected and syndromic clubfoot, developed new treatment for congenital vertical talus based on the principles of the Ponseti method, and designed a new dynamic clubfoot brace to improve strength and compliance.

Management of the Relapsed Clubfoot Following Treatment Using the Ponseti Method

The Ponseti method to treat idiopathic clubfoot deformity has proven to be reliable, and several centers have reported excellent outcomes. Although the method has been dependable in obtaining initial correction of the foot, relapse rates ranging from 26% to 48% have been reported. When a relapsed deformity is detected early, treatment with a short series of manipulations and cast applications followed by resumption of postcorrective bracing may be all that is required to regain and maintain correction. In patients aged >2.5 years, especially those who may be refractory to further brace use, deformity correction by preoperative cast treatment, followed by anterior tibial tendon transfer to the third cuneiform, is a good treatment option. Other procedures, such as combined cuboid-cuneiform osteotomy, posterior ankle and subtalar release, and, rarely, comprehensive posteromedial release or correction by gradual distraction, may be useful in select patients.

What is new in idiopathic clubfoot?

Idiopathic clubfoot has a tremendous worldwide prevalence. If left untreated, the deformity has severely disabling effects on mobility and quality of life. Given its prevalence and significance, numerous studies are published on this condition every year. In this article, we attempt to highlight important themes and findings of studies published on idiopathic clubfoot over the past 3 years.

Evolution of clubfoot deformity and muscle abnormality in the Ponseti method: evaluation with the Dimeglio score

PURPOSE

The modality of progression of the correction along casting sessions of Ponseti method has been poorly investigated and information regarding evolution of muscular abnormalities is missing. The aim of the study was to investigate dynamics of correction of the different components of clubfoot deformity in a clinical setting.

METHODS

In a prospective study, 124 clubfeet consecutively treated by a single orthopaedic surgeon were evaluated with the Dimeglio system at each casting session and score progression was determined.

RESULTS

For each component a typical pattern was recorded. Cavus and medial crease showed a rapid correction. Rotation, adduction and varus corrected gradually and simultaneously. The posterior crease usually persisted until final cast was discontinued. Equinus improved progressively after each cast and then to a larger extent with Achilles tenotomy. The parameter describing poor muscular condition, reported at presentation in 39 feet (31.5%), was the only item showing extremely different dynamics of correction (from rapid and complete resolution to persistence at last cast removal), which could be explained by the large diversity of entities included (hypertonia, imbalance, fatty infiltration, fibrosis, aplasia).

CONCLUSIONS

This study confirmed that dynamics of correction in clinical setting correspond essentially to theoretical principles of Ponseti method. Muscle abnormalities are not uncommon in clubfeet and have great influence on the progression of correction. If abnormalities are recorded, their evolution along the treatment should be monitored. A more objective evaluation would be required.

Deletions of 5' HOXC genes are associated with lower extremity malformations, including clubfoot and vertical talus

BACKGROUND

Deletions of the HOXC gene cluster result in variable phenotypes in mice, but have been rarely described in humans.

OBJECTIVE

To report chromosome 12q13.13 microdeletions ranging from 13 to 175 kb and involving the 5' HOXC genes in four families, segregating congenital lower limb malformations, including clubfoot, vertical talus and hip dysplasia.

METHODS

Probands (N=253) with clubfoot or vertical talus were screened for point mutations and copy number variants using multiplexed direct genomic selection, a pooled BAC targeted capture approach. SNP genotyping included 1178 probands with clubfoot or vertical talus and 1775 controls.

RESULTS

The microdeletions share a minimal non-coding region overlap upstream of HOXC13, with variable phenotypes depending upon HOXC13, HOXC12 or the HOTAIR lncRNA inclusion. SNP analysis revealed HOXC11 p.Ser191Phe segregating with clubfoot in a small family and enrichment of HOXC12 p.Asn176Lys in patients with clubfoot or vertical talus (rs189468720, p=0.0057, OR=3.8). Defects in limb morphogenesis include shortened and overlapping toes, as well as peroneus muscle hypoplasia. Finally, HOXC and HOXD gene expression is reduced in fibroblasts from a patient with a 5' HOXC deletion, consistent with previous studies demonstrating that dosage of lncRNAs alters expression of HOXD genes in trans.

CONCLUSIONS

Because HOXD10 has been implicated in the aetiology of congenital vertical talus, variation in its expression may contribute to the lower limb phenotypes occurring with 5' HOXC microdeletions. Identification of 5' HOXC microdeletions highlights the importance of transcriptional regulators in the aetiology of severe lower limb malformations and will improve their diagnosis and management.

Treatment of Severe Recurrent Clubfoot

Understanding the pathoanatomy of severe recurrent clubfoot and its implication on treatment options is important for the successful treatment. A comprehensive clinical evaluation of the different components helps in selecting procedures. Individual needs and social and psychological factors influencing treatment and the impact of treatment on the child have to be considered. With increasing dissemination and improved understanding of the Ponseti method, a further decrease in the frequency of severe recurrent clubfoot can be hoped for and expected.