Clinico-sonographical evaluation of idiopathic clubfoot and its correction by Ponseti method - A prospective study

Clubfoot: Congenital Talipes Equinovarus

Congenital talipes equinovarus (CTEV), also known as clubfoot, is a common musculoskeletal entity that affects one to two per 1000 live births worldwide. Imaging modalities including radiography, US, and MRI have emerged as valuable tools for the diagnosis, treatment, and monitoring of CTEV. The deformity is characterized by midfoot cavus, forefoot adductus, and hindfoot varus and equinus. The Ponseti method of manipulation and serial casting is the standard treatment of CTEV. Radiography shows the anatomy, position, and relationships of the different bones of the foot. US allows accurate assessment of cartilaginous and bony structures, in addition to its inherent advantages such as absence of ionizing radiation exposure. One of the indications for US is to monitor the response to Ponseti method treatment. MRI enables visualization of bones, cartilage, and soft tissues and allows multiplanar evaluation of deformities, providing a comprehensive imaging analysis of CTEV. An integrated approach that combines clinical examination and imaging findings is essential for effective management of CTEV. The authors provide a comprehensive overview of CTEV with a review of imaging modalities to help evaluate CTEV, focusing on radiography, US, and MRI. Using this article as a guide, radiologists involved in the assessment and treatment of CTEV can contribute to the management of the condition. ©RSNA, 2024 Supplemental material is available for this article.

The diagnostic dilemma of congenital foot deformity in pediatrics: could adding ultrasound be problem solving?

Background

Foot deformity is one of the most common congenital musculoskeletal anomalies in the pediatric age group. Accurate diagnosis can be sometimes impossible to be established clinically. In the assessment of foot abnormalities, radiology plays a crucial role. Lack of ossification of the tarsal bones renders plain radiographs of the foot as of little diagnostic value in this age group. MRI apart from its cost requires anesthesia and sedation. In contrast, ultrasonography allows for the imaging of cartilaginous structures. As a result, newborn foot abnormalities can be thoroughly assessed. The whole anatomy of the foot is evaluated using several scanning views. Additional planes may be needed to show the pathologic features of a specific deformity. The purpose of this study was to demonstrate the additive value of ultrasound to plain radiographs in the assessment of foot deformities in the pediatric age group.

Results

This case–control study was performed on sixty children, 30 of which were patients admitted from the pediatric orthopedic clinic, presenting with foot deformity, after being examined clinically. Antero-posterior and lateral radiographs of foot, tibiocalcaneal, antero-posterior talocalcaneal, and lateral talocalcaneal angles were measured. Sonographic examination was done in different projections of both feet, while the patient is lying supine with dynamic sonography. The sonographic parameters measured were as follows: medial malleolar–navicular distance and medial soft tissue thickness on medial projection, calcaneocuboid distance on lateral projection, talonavicular relation on dorsal projection, and tibiocalcaneal distance on posterior projection. There was a statistically significant difference between patients and controls in the medial malleolar–navicular distance and medial soft tissue thickness measured on the medial view, the calcaneocuboid distance recorded on the lateral view, and the tibiocalcaneal distance measured on the posterior view.

Conclusions

Ultrasonography has a growing and useful role as a complementary imaging modality in the evaluation and follow-up of pediatric patients with foot deformity.

Ultrasound measurements in clubfoot treated with the Ponseti method and risk factors for recurrence: A retrospective study

Background

Recurrence remains the main challenge in the treatment of clubfoot. The primary goal of this study is to determine if ultrasound measurements are associated with recurrence after successful management with the Ponseti method. Furthermore, other factors are identified which can be associated with recurrence of the deformity.

Methods

Seventy-six infants (114 idiopathic clubfeet), all treated with the Ponseti technique were reviewed. All patients had an ultrasound evaluation by the same radiologist at the beginning of the treatment. Recurrence, defined as the need to return to Ponseti casting, was recorded at a mean follow-up of 5 years. Measurements of association with recurrence were obtained for the following ultrasound measures: the medial talonavicular displacement (MTa-N), the medial malleolus to navicular distance (MM-N), the talocalcaneal angle (Ta-C), and the distal tibial physis to proximal calcaneal apophysis distance (Ti-C). Subsequently, a multivariate logistic regression analysis modeling recurrence examined patients' characteristics, compliance, Achilles tenotomy, and ultrasound measurements.

Results

Recurrence rate was 22% noted in 17 patients. On univariate analysis, relapse was associated with increased MTa-N (p = 0.038), decreased MM-N (p = 0.008), and decreased Ti-C (p = 0.023). On multivariate analysis, we identified the Ti-C as the only ultrasound measurement significantly associated with recurrence (p = 0.026). Other significant predictors for relapse in this study were noncompliance with orthosis (OR = 139.0 (95% CI: 8.7-2224.0), p < 10-3), and omitting percutaneous Achilles tenotomy in clubfoot treatment (OR = 23.9 (95% CI: 1.2-493.6), p = 0.041).

Conclusion

The Ti-C sonographic measurement at the start of treatment can be a useful adjunct to help identify high-risk patients for recurrence of deformity. Non-compliance with bracing and omitting percutaneous Achilles tenotomy are also predictive factors.

Level of evidence

Prognostic study, Level III.