The association between Body Mass Index (BMI) and knee pain on flexible flat foot among students at Universitas Warmadewa, Bali, Indonesia

Abstract

Background: Flatfoot (pes planus) causes mechanical pressure in the knee and increases contact between the patellar articulation surfaces, increasing knee pain. The weight gain can increase the risk of flatfoot because of excessive loading and ligament stretching beyond the elastic limit. This study aims to determine the association between body mass index (BMI) and knee pain on flexible flat foot among students at Universitas Warmadewa, Denpasar.Methods: A cross sectional analytic study was conducted among 100 new students of the Universitas Warmadewa Denpasar between May-December 2019. Flat foot screening was carried out using the wet footprint test and plantar arch index (PAI) measurement. BMI was measured through the weight and height of the sample. Patellofemoral pain was measured using the Kujala anterior knee pain scale questionnaire. Descriptive analysis was analyzed by SPSS version 20 for Windows to determine the mean, SE, maximum, and minimum value of all ratio variables. The correlation was tested with Spearman with a significance level of p <0.05.Results: The average BMI value was 27.6 kg/m2, the average PAI of the right foot was 1.42, the average PAI of the left foot was 1.48, and the average score of the Kujala score was 77.22. There was a positive correlation between BMI with flexible flat foot on the right and left foot with significant results (p = <0.05, r = -0.24; p = <0.05, r = 0.307 respectively). There was a negative correlation between Kujala score with flexible flat foot on the right and left foot with significant results (p = <0.05, r = -0.238; p = <0.05, r = -0.366 respectively).Conclusion: Flexible flat foot significantly correlates to BMI and Kujala score. The higher BMI value, the PAI leg will be higher. The higher PAI value of the foot, the Kujala score will be lower.