Relationship Between Body Mass Index and Severity of Plantar Fasciitis in Adults

Abstract

Background: Plantar fasciitis is a frequent cause of heel pain and functional impairment, and symptom burden may increase with excess body weight due to greater mechanical loading on the plantar fascia. Evidence relating body mass index (BMI) to plantar fasciitis severity remains limited in Pakistani adult populations. Objective: To determine the relationship between BMI and plantar fasciitis severity in adults. Methods: A cross-sectional study was conducted at the University of Lahore Teaching Hospital among 196 adults aged 20–45 years with clinically diagnosed plantar fasciitis confirmed by positive Windlass test. BMI was calculated and categorized using WHO thresholds. Severity was assessed using the Numeric Pain Rating Scale (NPRS) and Foot Function Index-Revised (FFI-R). Spearman correlation tested associations between BMI and severity scores, and chi-square assessed categorical relationships between BMI groups and severity strata using SPSS v22. Results: Participants had mean BMI 26.28 ± 5.71 kg/m², with 30.1% overweight and 29.1% obese. BMI correlated strongly with NPRS (r = 0.844, p < 0.001) and FFI total disability (r = 0.771, p < 0.001). Obese participants demonstrated markedly higher severe pain frequency than normal and underweight groups (χ² = 86.09, p < 0.001) and greater disability (χ² = 49.18, p < 0.001). Conclusion: Higher BMI is strongly associated with greater pain intensity and disability in plantar fasciitis, supporting BMI-based risk stratification and integration of weight-management strategies into rehabilitation