Prenatal ultrasound diagnosis of congenital vertical talus

OBJECTIVE

This study aimed to analyze the ultrasound characteristics of fetal congenital vertical talus (CVT) to provide a detailed basis for the prenatal diagnosis of CVT.

METHODS

We retrospectively analyzed the ultrasonographic findings of fetuses with CVT confirmed by X-ray, surgery, or autopsy from 2010 to 2020. Clinical characteristics and ultrasonographic findings of CVT, including foot morphology, ossification center of the calcaneus and talus, associated deformities, and chromosomal test results, were recorded.

RESULTS

Thirteen patients diagnosed with CVT by prenatal ultrasound were confirmed postpartum. Nine cases were bilateral, and four were unilateral. Under two-dimensional ultrasound, 13/13 cases had abnormal foot morphology, and 10 of 13 cases (76.9%) showed that the ossification center of the talus moved downward, and the calcaneus moved laterally. Under three-dimensional ultrasound, 11 cases (84.6%) presented a "rocking chair" appearance, and two cases did not obtain satisfactory three-dimensional image due to oligohydramnios and fetal position. In this group of cases, two cases (15.4%) were isolated CVT, and the other 11 cases (84.6%) were complicated with other abnormalities. Eleven cases of non-isolated CVT and 1 case of isolated CVT were induced, and another patient with isolated CVT had undergone postnatal surgery, which had been followed up for 8 years and recovered well.

CONCLUSIONS

The combination of fetal foot morphology, ossification center position of the calcaneus and talus, and three-dimensional ultrasound can provide a reliable diagnosis of CVT. Furthermore, we should pay more attention to the evaluation of other systemic and chromosomal abnormalities in CVT cases.

Corrective bandages and daily manipulations for treatment of congenital vertical talus: a thirteen year follow-up

PURPOSE

To analyze the results of a conservative method for treating congenital vertical talus in children with early start and to know in which cases surgical treatment was needed.

METHODS

A retrospective analysis of all children diagnosed with idiopathic vertical talus was carried out during the years 2008-2021. Thirty-two children (46 feet) were finally included. Children were treated with serial manipulations, muscle stimulation, and corrective bandages. Age at the time of initiation of treatment, duration of treatment, and correction or not of the deformity without surgical intervention were recorded as variables of interest. The talocalcaneal angle, TAMBA, and ankle range of motion were measured before treatment, after treatment, and at the end of the follow-up period. Statistics decision tree was used to determine which variable best discriminated whether the patient needed surgery. To complement the tree diagram, a two-step cluster analysis was carried out.

RESULTS

After treatment, TAMBA and talocalcaneal angle changed from "vertical" to "oblique" category in 45 and 37 feet, respectively. The pathological dorsal flexion of the ankle changed to normal in 37 feet and ankle plantar flexion was normal in 46 feet. These variables showed significant changes between the three measurement moments. The results of the statistics decision tree and cluster analysis indicate that "No surgery" was associated with an age equal to or lower than one week when treatment was started, and with an ankle plantar flexion range of motion lower than 36°.

CONCLUSIONS

The beginning of this conservative treatment in the first week of life and having a plantar flexion of the ankle lower than 36° were related to the success of the treatment without surgery.

Diagnostic yield of exome sequencing in congenital vertical talus

BACKGROUND

Congenital vertical talus (CVT), also known as "rocker-bottom foot", is a rare foot deformity associated with a dislocation of the talonavicular joint. Although genetic causes of CVT have been described in single isolated and syndromic families, whole-exome sequencing (WES) of large cohorts have not yet been reported.

METHODS

In this study, 62 probands with CVT were evaluated for likely causative single nucleotide variants (SNVs) and copy number variants (CNVs) using WES. Segregation of variants within families was determined by Sanger sequencing.

RESULTS

In this cohort, CVT occurred as an isolated anomaly in 75.8% (47/62) and was familial in 19.3% (12/62) of cases. Analysis of WES data led to the identification of likely causative variants in known disease genes in 30.6% (19/62) of all CVT probands. More than one proband had likely causative SNVs in TSHZ1, GDF5, and LMX1B. Only two probands had likely causative CNVs: a chromosome 12q13.13 deletion of the 5' HOXC gene cluster, and a chromosome 18q22.3q23 deletion involving TSHZ1. Familial CVT was strongly predictive of identifying a molecular diagnosis [75% (9/12) of familial cases compared to 20% (10/50) of non-familial cases (Chi-square test, P-value = 0.0002)]. There was no difference in the solved rate based on isolated or syndromic presentation, unilateral or bilateral affectation, or sex.

CONCLUSIONS

CVT is genetically heterogeneous and more often caused by SNVs than CNVs. There is a high yield of WES in familial CVT cases (∼75%). Additional research is needed to identify the causes of sporadic CVT, which had much lower solved rates.

Congenital Vertical Talus

Congenital vertical talus represents a congenital structural foot deformity characterized by the classical rocker bottom deformity. The main feature is dislocation of the talonavicular joint along with contractures of the dorsolateral tendons of the foot and tendo Achilles. In the past treatment consisted of 2- or single-stage more or less extensive soft tissue releases including reduction of the talonavicular joint following casting in the first phase. Nowadays all feet are treated by serial casting, closed or miniopen talonavicular joint reduction, and percutaneous achillotenotomy. Functional results of the miniinvasive method are superior to those of the former more extensive surgical releases.

Multimodality imaging of the paediatric flatfoot

Flatfoot is commonly encountered in the paediatric population and describes a spectrum of clinical and radiological presentations which encompass both normally developing and pathological feet. Flatfoot can be categorised as flexible or rigid, a distinction which has important implications when considering the potential underlying aetiology and treatment options, and therefore imaging is an important component of the diagnostic workup. Weight-bearing plain radiographs are established initial investigations, although the significance of a number of the commonly derived quantitative parameters in children remains unclear. CT and MRI are important additional imaging modalities reserved for the investigation of symptomatic cases or those in which an underlying structural abnormality is suspected, rigid flatfoot commonly falling into one of these two categories. We review and illustrate the multimodality imaging of the paediatric flatfoot, with reference to both qualitative and quantitative radiographic assessment and cross-sectional imaging appearances.

Prenatal congenital vertical talus (rocker bottom foot): a marker for multisystem anomalies

BACKGROUND

Congenital vertical talus is a rare foot anomaly characterized by a prominent calcaneus and rigid forefoot dorsiflexion. While congenital vertical talus has been associated with anomalies such as trisomy 18, myelomeningocele and arthrogryposis, postnatal series have reported cases of isolated congenital vertical talus.

OBJECTIVE

The purpose of our study was to determine the incidence of isolated congenital vertical talus prenatally and identify the most common anomalies associated with this finding.

MATERIALS AND METHODS

A retrospective review was performed of congenital vertical talus cases identified in our fetal center from 2006 to 2015. The prenatal US and MR imaging appearance of congenital vertical talus was evaluated and differentiation from congenital talipes equinovarus was assessed. Studies were evaluated for additional abnormalities affecting the central nervous system, face, limbs, viscera, growth and amniotic fluid. Imaging findings were recorded and correlated with outcomes when available.

RESULTS

Twenty-four cases of congenital vertical talus were identified prenatally (gestational age: 19-36 weeks). All 24 had prenatal US and 21 also underwent fetal MRI on the same day. There were no isolated cases of congenital vertical talus in this series; all 24 had additional anomalies identified prenatally. Sixteen cases had bilateral congenital vertical talus (67%). Additional anomalies were identified in the brain (15), spine (11), face (6), abdominal wall (3), heart (8) and other limbs (12). Chromosomal abnormalities were identified in 6 of 20 patients who underwent genetic testing. Overall, US held some advantage in detecting the abnormality: in 10 cases, US depicted congenital vertical talus more clearly than MRI; in 8 cases, US and MRI were equal in detection and in 3 cases, MRI was superior. In 9/15 cases with intracranial abnormalities, MRI was superior to US in demonstrating structural anomalies. Outcomes included termination (11), intrauterine fetal demise (1), stillbirth or immediate neonatal demise (5), lost to follow-up (1), and 6 survivors with postnatal follow-up.

CONCLUSION

In our series, there were no cases of isolated congenital vertical talus, with additional anomalies variably affecting multiple systems including the brain, spine, face, viscera and limbs. When congenital vertical talus is identified prenatally, a thorough search for additional anomalies is indicated. Fetal MRI can be a useful adjunct in confirming the diagnosis and further delineating additional anomalies, particularly in the brain and spine.

A comparison of the Dobbs method for correction of idiopathic and teratological congenital vertical talus

INTRODUCTION

Congenital vertical talus (CVT) is a rare deformity. Traditionally, CVT correction involved extensive soft tissue releases, and this was associated with high complication rates. The Dobbs method is less invasive and comprises serial manipulation and casting, followed by minimally invasive reduction and K-wire fixation of the talonavicular joint and percutaneous Achilles tenotomy.

AIM

The purpose of our study was to compare the outcomes of using the Dobbs method for CVT correction in idiopathic and teratological patients.

METHODS

A retrospective analysis of all patients treated with the Dobbs method for CVT between the years 2007 and 2012 was carried out. Notes, electronic records and radiographs were reviewed for every patient. The Oxford ankle foot score was obtained at follow-up.

RESULTS

There was a total of ten children with 18 affected feet. Five children (ten feet) had teratological CVT. Recurrence was noted in six feet (two from the idiopathic group and four from the teratological group). The median age was 5 months (range 2-8 months). The mean follow-up was 53 months (range 24-80 months). There was a significant difference between pre-operative to initial post-operative and pre-operative to latest follow-up measurements for all angles in the successfully treated CVT group (p < 0.000001). The mean Oxford ankle foot scores for each domain in all patients are 59.9 (physical), 88.8 (school and play) and 99.1 (emotional).

CONCLUSION

The Dobbs method is a less invasive technique of CVT correction. It is an effective initial method of treatment in both teratological and idiopathic patients. A higher recurrence rate was observed in the teratological group, although this was not statistically significant.

Syndromic Feet: Arthrogryposis and Myelomeningocele

Treatment of myelomeningocele and arthrogrypotic foot deformities has been controversial; many different procedures have been advocated for each type of deformity. In most cases, outcomes have had variable success rates, and many complications can occur. Treatment strategies should highlight care that avoids the development of a stiffened foot and allows for a variety of options to regain correction when a relapse occurs. This is particularly true in myelomeningocele, whereby a stiff foot runs a high risk for skin ulceration, leading to osteomyelitis. Discussion includes appropriate circumstances for the use of presented procedures and the author's preferred treatment for each deformity.

Reverse Ponseti-type treatment for children with congenital vertical talus: comparison between idiopathic and teratological patients

Children with congenital vertical talus (CVT) have been treated with extensive soft-tissue releases, with a high rate of complications. Recently, reverse Ponseti-type casting followed by percutaneous reduction and fixation has been described, with excellent results in separate cohorts of children with CVT, of either idiopathic or teratological aetiology. There are currently no studies that compare the outcome in these two types. We present a prospective cohort of 13 children (21 feet) with CVT of both idiopathic and teratological aetiology, in which this technique has been used. Clinical, radiological and parent-reported outcomes were obtained at a mean follow-up of 36 months (8 to 57). Six children (nine feet) had associated neuromuscular conditions or syndromes; the condition was idiopathic in seven children (12 feet). Initial correction was achieved in all children, with significant improvement in all radiological parameters. Recurrence was seen in ten feet. Modification of the technique to include limited capsulotomy at the initial operation may reduce the risk of recurrence. The reverse Ponseti-type technique is effective in the initial correction of CVT of both idiopathic and teratological aetiology. Recurrence is a problem in both these groups, with higher rates than first reported in the original paper. However, these rates are less than those reported after open surgical release.

Primary outcomes of the congenital vertical talus correction using the Dobbs method of serial casting and limited surgery

INTRODUCTION

The traditional treatment for congenital vertical talus, which involves serial casting and extensive soft-tissue releases, has been associated with severe stiffness and other complications in adolescents and adults. Our hypothesis is that favorable results will be obtained using the Dobbs method of serial manipulation, casting, and limited surgery for vertical talus correction, even in older children and syndromic cases. Therefore, the present study aimed at evaluating the Dobbs method in such cases.

MATERIALS AND METHODS

We treated 15 feet of 10 patients (aged from 1 month to 9 years) using manipulation and serial casting or the reverse Ponseti method followed by percutaneous Achilles tenotomy and limited open reduction of the talonavicular joint. All patients were evaluated both clinically and radiologically in a mean follow-up period of 2 years.

RESULTS

After 2 years, all patients had plantigrade and flexible feet with good radiographic correction. The mean talocalcaneal angle before (70.5° ± 10.5) and after (31° ± 5.2) treatment and the talar axis metatarsal base angle before (60° ± 11.4) and after (15° ± 6.7) treatment were significantly improved (P < 0.001).

DISCUSSION

Recent research has shown that manipulation and serial casting followed by limited surgery (Dobbs method) was successful in treating idiopathic congenital vertical talus. Our results also showed that this method resulted in an excellent outcome in both idiopathic and syndromic congenital vertical talus, even in older children.