Is there a correlation between static radiographs and dynamic foot function in pediatric foot deformities?

Abstract

Background: Idiopathic flexible flatfeet, congenital clubfeet and pes cavovarus are the most common foot deformities in children. Accurate assessment to quantify the severity of these deformities by clinical examination alone can be challenging. Radiographs are a valuable adjunct for accurate diagnosis and effective treatment. However, static radiographs during relaxed standing may not reflect the dynamic changes in the foot skeleton during functional activities such as walking. Therefore, the aim of this study is to predict dynamic foot movements during walking from planar standing radiographs to reveal the significance of the radiographic analysis for the assessment of foot function.

Methods: Patients 8-17 years with flexible flatfeet (FFF, n=217) recurrent clubfeet (RCF n=38) and overcorrected clubfeet (OCCF, n=71) of non-neurogenic or syndromic origin and pes cavovarus due to peripheral neuropathy (PNP, n=48) were retrospectively included. Patients underwent gait analysis with the Oxford Foot Model and radiographic examination in anterior-posterior and lateral view during standing. Multilinear predictor analysis of selected gait parameters was performed based on radiographic measures.

Results: The variance that was explained by radiography was greatest for the transverse plane forefoot abduction with 33% for OCCF, 50% for RCF and 59% for PNP. Flatfeet and foot kinematics in the other planes or between rearfoot and tibia showed little or no relation.

Conclusions: The static measures of foot deformities by radiography could explain only a small amount of variance in foot kinematics during walking, in particular for FFF. An explanation may be that the forces during weight bearing bear little resemblance to those during gait in terms of neither magnitude nor direction. These findings suggest that foot function cannot be accurately assessed solely from static radiographic observations of the foot, commonly undertaken in clinical practice.

Keywords: Clubfeet; Flat feet; Foot deformities; Pes cavovarus; Radiographs; Walking.