Association between body mass index and medial longitudinal arch parameters: a systematic review and meta-analysis of observational studies

Abstract

Foot structure and function are influenced by biomechanical and anthropometric factors, with Body Mass Index (BMI) proposed as an important determinant. Elevated BMI may be associated with alterations in the medial longitudinal arch (MLA); however, existing evidence is inconsistent, warranting a meta-analysis. Electronic databases were searched for observational studies. Risk of bias was assessed using the ROBINS-E tool. Correlation coefficients were extracted and pooled using random-effects models. Subgroup analyses were performed to explore variations across demographic and methodological factors. Twenty-nine studies were included in the pooled analysis. A small but significant positive correlation was found between BMI and the Foot Posture Index ( r = 0.16, 95% CI: 0.07 to 0.24, p < 0.001). A moderate positive correlation was observed between BMI and the Arch Index ( r = 0.35, 95% CI: 0.26 to 0.43, p < 0.001). While associations varied by age, geographic region, and measurement method, the overall pattern suggests decreased MLA height in individuals with higher BMI. Higher BMI is associated with alterations in MLA structure. The findings suggest that weight status should be considered when evaluating foot posture, particularly in adults, as individuals with overweight or obesity have been found to demonstrate greater midfoot loading and related structural changes. Further controlled studies with standardized methodologies are needed to provide more precise estimates of the association.