An Analysis of the Mechanical Properties of the Ponseti Method in Clubfoot Treatment

A Rare Presentation of Bifid Tibialis Anterior Tendon in a Case of Idiopathic Congenital Talipes Equinovarus

Introduction

Idiopathic congenital talipes equinovarus (CTEV) is one of the most extensively researched topics for decades. It has been associated with various musculoskeletal anomalies which maybe bony, vascular or involving the ligaments and muscles which may have a direct or indirect impact on its pathoanatomy. This report describes an unusual presentation of a bifid tibialis anterior tendon (TAT) in a case of CTEV. This is the first report of this kind in the literature to the best of our knowledge.

Case Report

A 4-year-old female presented with bilateral relapsed CTEV with dynamic supination previously treated with standard Ponseti protocol. The patient was treated with TAT transfer on the left side with a rare presentation of a bifid TAT where both the slips of the tendon were transferred to dorsum of the foot onto the lateral cuneiform.

Conclusion

When treating a patient of CTEV surgically, it is important to consider the possibility of a bifid TAT which is a rare musculoskeletal association. It is recommended to carefully dissect TAT to prevent under correction of the deformity in case either one of the tendon slips remains attached to its original site.

Congenital Talipes Equinovarus Management and Outcomes: The Experiences of Pediatric Tertiary Centers in Abha, Saudi Arabia

BACKGROUND

Congenital talipes equinovarus (CTEV), also known as clubfoot, describes a range of foot abnormalities usually present at birth (congenital) in which a baby's foot is twisted out of shape or position. In clubfoot, tendons are shorter than usual. Clubfoot is a fairly common birth defect and is usually an isolated problem for an otherwise healthy newborn.

AIM

This study aimed to investigate the experiences of pediatric tertiary centers in Abha, Saudi Arabia, regarding the management, frequency, treatment options, and outcomes of CTEV.

METHODS

A retrospective chart review of pediatric patients with clubfoot was conducted to evaluate the number of cases, treatment options, and outcomes at Abha Maternity and Children Hospital and Khamis Mushait Maternity and Children Hospital. Data were extracted independently using prestructured data extraction forms. The collected data included demographic and medical information, family history, clinico-epidemiological information, risk factors, management options, and complications of clubfoot.

RESULTS

The study included 89 children with CTEV from the target hospitals. Their ages ranged from 20 days to six years, with a mean age of 10.5 ± 14.5 months. Of these, 57 (64%) were male. CTEV was unilateral in 53 (59.5%) cases and bilateral in 36 (40.5%) cases. The majority of the cases had isolated CTEV. Nearly all cases had Ponseti casting with a tendo-Achilles tenotomy (TAT) surgical procedure. Patient follow-up ranged from one week to three years, with an average follow-up of 3.1 months. Only three (3.4%) cases experienced recurrence of deformity after management.

CONCLUSION

Ponseti casting with the tendo-Achilles tenotomy approach emerged as the most commonly employed management option, demonstrating a low rate of recurrence.

Congenital talipes equinovarus: A literature review

Congenital talipes equinovarus (CTEV) is a congenital disability characterized by leg deformities in the cavus, adducts, varus, and equinus. The etiology of CTEV is poorly understood, despite its incidence ranging from 0.76 to 3.49 cases per 1000 live births in Indonesia. CTEV involves the fixation of the foot in the adducts, varus, and equinus with concurrent soft tissue anomalies. Despite advances in treatment, disability often persists. Theoretical models have been proposed for neurological, vascular, connective tissue, bone, and muscular causes; however, the currently available data suggests that mild cases are associated with intrauterine position. CTEV's etiology appears to involve a hereditary component, as its prevalence varies by ethnic group. Genetic factors have been identified in 24–50% of cases, depending on the community studied. Based on a complex segregation analysis, the most plausible inheritance pattern is a single large-effect gene interacting with a polygenic background.

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CTEV is a congenital disability characterized by leg deformities in the cavus, adducts, varus, and equinus.

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In Indonesia, its incidence ranges from 0.76 to 3.49 cases per 1000 live births.

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Genetic factors have been identified in 24–50% of cases, depending on the community studied.

Achilles tendon surgery in clubfoot: Are long term sequelae predictable?

Congenital Clubfoot (CCF) treatment involves a surgical procedure on the Achilles tendon most of the time, i.e. tenotomy or, in selected cases, Z-plasty lengthening. Many authors have studied the outcomes of Achilles tenotomy, describing complete clinical and ultrasound tendon fibers integrity restoration 3-6 weeks after surgery. Nevertheless, little is known about the mechanical properties of the operated tendon. Recently, cases of subcutaneous rupture of the Achilles tendon have been described in adolescents who practiced sports and who had undergone Achilles tenotomy for congenital clubfoot in childhood. Authors report two cases of atraumatic Achilles tendon injury (subcutaneous rupture and intratendinous ossification) in adult patients who had been treated for congenital clubfoot in childhood. In both cases, no causes determining the injury were identified; in the medical history there was a Z-plasty lengthening of the Achilles tendon, performed within the first year of life, which could be considered a predisposing factor. The usefulness of long-term monitoring of patients treated for CCF with surgical procedures on the Achilles tendon is therefore hypothesized, in order to promptly identify by symptoms, clinical pictures and ultrasound criteria, tendon suffering that may predispose subcutaneous rupture.

Effect of loading history on material properties of human heel pad: an in-vivo pilot investigation during gait

BACKGROUND

This study was aimed to develop a novel dynamic measurement technique for testing the material properties and investigating the effect of continuous compression load on the structural and mechanical properties of human heel pad during actual gait.

METHODS

The dual fluoroscopic imaging system (DFIS) and dynamic foot-ground contact pressure-test plate were used for measuring the material properties, including primary thickness, peak strain, peak stress, elastic modulus, viscous modulus and energy dissipation rate (EDR), both at time zero and following continuous loading. Ten healthy pilot subjects, aged from 23 to 72 (average: 46.5 ± 17.6), were enrolled. A "three-step gait cycle" is performed for all subjects, with the second step striking at a marked position on the force plate with the heel to maintain the location of the tested foot to be in the view of fluoroscopes. The subjects were measured at both relaxed (time-zero group) and fatigue (continuous-loading group) statuses, and the left and right heels were measured using the identical procedures.

RESULTS

The peak strain, peak stress, elastic modulus, and EDR are similar before and after continuous load, while the viscous modulus was significantly decreased (median: 43.9 vs. 20.37 kPa•s; p < 0.001) as well as primary thicknesses (median: 15.99 vs. 15.72 mm; p < 0.001). Age is demonstrated to be moderately correlated with the primary thicknesses both at time zero (R = -0.507) and following continuous load (R = -0.607). The peak stress was significantly correlated with the elastic modulus before (R = 0.741) and after continuous load (R = 0.802). The peak strain was correlated with the elastic modulus before (R = -0.765) and after continuous load (R = -0.801). The correlations between the viscous modulus and peak stress/ peak strain are similar to above(R = 0.643, 0.577, - 0.586 and - 0.717 respectively). The viscous modulus is positively correlated with the elastic modulus before (R = 0.821) and after continuous load (R = 0.784).

CONCLUSIONS

By using dynamic fluoroscopy combined with the plantar pressure plate, the in vivo viscoelastic properties and other data of the heel pad in the actual gait can be obtained. Age was negatively correlated with the primary thickness of heel pad and peak strain, and was positively correlated with viscous modulus. Repetitive loading could decrease the primary thickness of heel pad and viscous modulus.

Clubfoot management in the Middle East: a survey-based review

Clubfoot is the most frequent congenital deformity involving the foot. Little is known about the management of this disease in the Middle East as sparse data is available in the literature. Through the last 5 decades, congenital clubfoot management in the Middle East went from manipulation through Kite’s technique in the late seventies, to early primary surgical intervention in the late eighties and early nineties of the previous century, and then back to manipulation with Ponseti’s technique and the French functional technique in the late nineties, with the latter falling out of favor with time. This is comparable to the evolution of management witnessed in the United States and in Europe, with 10 to 15 years of delay. The delay is getting shorter with time due to the easier access to published scientific data and the increasing number of fellows from Middle East travelling to referral centers in Europe and the USA. A survey was performed among pediatric orthopedic surgeons in the Middle East to assess their approach to clubfoot management. This is the first survey of its kind in the region. It showed a wide adoption (97.1%) of the Ponseti’s technique with serial manipulation and casting, Achilles tenotomy followed by abduction bracing. Divergent practices were found concerning the upper age limit for Ponseti treatment and the setting of the Achilles tenotomy. Nevertheless, these subjects are still a matter of debate in the literature and international conferences. All in all, pediatric orthopedic surgeons in the Middle East are offering their patients the gold standard of care. However, lot of work is to be done in raising awareness for this disease in the community, and among our colleagues as prenatal screening for clubfoot in the Middle East is practically nonexistent.

Clubfoot pathology in fetus and pathogenesis. A new pathogenetic theory based on pathology, imaging findings and biomechanics-a narrative review

Several studies have described the pathology of idiopathic congenital clubfoot (ICCF) in fetus. Numerous pathogenetic theories have been postulated on ICCF, but many of them lack any objective evidence. Pathologic studies in fetus together with MRI studies in patients with ICCF seem to favor the theory of a muscular imbalance of the foot activators during fetal growth as the main pathogenetic factor of ICCF. Our objectives were: (I) To support the theory of muscular imbalance as the primary pathogenetic factor of ICCF; (II) To clarify why atrophy and shortening affect the activator muscles of the foot unevenly, as reported by literature. A literature search based on MEDLINE and the COCHRANE database was performed to identify all published studies from 1929 to 2020 which report ICCF pathology in fetus, its etiopathogenesis, and imaging and biomechanical studies showing how the basic pathology may be addressed by Ponseti treatment. A manual search was also performed of the references cited in studies, reviews, and university libraries. Altered size, shape and articular relationships of the tarsal bones, and uneven atrophy and shortening of the leg muscles together with capsule and ligament abnormalities were the main pathologic findings reported in fetus with ICCF. Regarding ICCF pathogenesis, the main debate is between the advocators of a primitive blastemal defect of the tarsal bones leading to the skeletal abnormalities and those who hold that the latter are secondary to a deforming force generated by the soft tissues. Imaging studies have shown that the Ponseti method is able to address the skeletal abnormalities, the correction of which is maintained until adulthood, whereas leg muscle atrophy is not improved but tends to worsen with growth. Preliminary histochemical studies of the soleus-Achilles tendon junction have shown a decrease of the growth factors and the presence of myostatin, both down-regulators of muscle growth in patients with ICCF. The authors postulate that a defect of both the radial and the longitudinal growth unevenly affecting the leg muscles with a consequent imbalance of the foot activators might be the main pathogenetic factor of ICCF. Further studies are needed to confirm this theory.

Congenital Talipes Equinovarus: Results of Treatment and Are We Bracing Effectively?

The aim of this retrospective study was to assess our management of Congenial Talipes Equinovarus (CTEV) in relation to national standards published by the British Society for Children's Orthopaedic Surgery (BSCOS). A secondary aim was to evaluate if a more tailored bracing regime than advocated in the traditional Ponseti technique, would be appropriate for some cases of CTEV. One hundred and thirty-three feet in 96 patients were treated between June 2006 and January 2016. All patients were clinically assessed prospectively by the senior author at initial presentation using the Harrold & Walker classification system. A combination of the senior author's database, Elogbook and trust IT systems were used for data collection. The results of Ponseti surgical procedures such as tendoachilles release and tibialis transfer fell within the BSCOS guidelines. The rate of radical subtalar surgical release was higher than advocated (12.3%) which was partly due to the number of primary syndromal patients in the series. There was a significantly lower mean time spent in bracing of 14.3 months (95% confidence interval 14.8-19.3) compared to recommended national guidelines. There was a clinically significant difference in the lower relapse rate of female patients compared to male patients and also a higher propensity of surgical intervention in male patients. In addition, there was a statistically significant difference in both time spent in bracing, between H&W classifications and between patients who had bracing removed pre walking age or post walking age. This potentially demonstrates a more tailored bracing regime may be possible when applied to less severely affected feet and the condition may be more benign in female cases.

Sonoelastographic Findings in Clubfeet

Purpose

One of the main features of congenital idiopathic clubfoot is the increased stiffness of soft tissues. With the growing popularity and availability of sonoelastography as a method to assess the stiffness of different tissues, we considered applying it to congenital clubfeet in order to to determine whether sonoelastography can be a useful imaging method for the evaluation of clubfeet, to assess whether there are any differences in stiffness of specific tendons between clubfeet and normal contralateral feet and to observe which treatment methods have an impact on the aspect of these structures on the elastograms.

Patients and Methods

A case-control study was performed involving 10 adolescent patients with unilateral idiopathic congenital clubfeet who were treated either with the Ponseti method or surgically with posteromedial release (PMR) during early infancy. Using compression sonoelastography, we obtained semi-quantitative data expressed as fat to tendon ratios in treated clubfeet and normal contralateral feet. The tendons of the following muscles were examined: tibialis anterior, tibialis posterior, flexor hallucis longus, peroneus longus and Achilles tendon at three levels (calcaneal insertion, lengthened zone and musculotendinous junction).

Results

The only statistically significant difference in the strain ratio (p = 0.023) between clubfeet and normal feet was at the level of the calcaneal insertion of the Achilles tendon, which was stiffer in clubfeet. Although other differences were not statistically significant, they may reflect some of the pathological modifications of clubfeet.

Conclusion

Overall, sonoelastography may be a useful examination tool in the quantitative and qualitative assessment of soft tissue stiffness in clubfeet, but further research is necessary.