What Makes Plantar Heel Spur Painful? A Matched Case-Control Study

CATEGORY: Hindfoot; Other INTRODUCTION/PURPOSE: Plantar heel spur has been considered one of the reasons for heel pain in plantar fasciitis although its pathophysiology is not clear. The purpose of this study is to investigate the demographic and radiographic differences between the plantar fasciitis cohort and age/sex-matched control cohort, and identify risk factors that make plantar heel spurs painful. METHODS: Patients who visited the office under the diagnosis of plantar fasciitis from September 2020 to December 2021 and age/sex-matched control cohort were included. Demographics and radiographic findings between the two groups were compared. A subgroup analysis was performed on only patients who had plantar heel spur. Patients who had plantar feel spur from the study group and the control group were extracted. All demographics and radiographic data were compared between the two subgroups and a multivariable logistic regression analysis was performed to identify independent risk factors that make plantar heel spur painful. RESULTS: 76 patients were enrolled in the study group (Painful heel) and age/sex-matched control group (Non-painful heel). BMI was significantly higher in the study group compared to the control group: 33.2 vs 28.7 (P < .001). In the study group, plantar heel spur was present in 67.1% (51 out of 76), while in 38.2% (29 out of 76) in the control group (P < .001). In the subgroup analysis, BMI in the study group was significantly higher compared to the control group: 34.6 vs 30.3 (P < .001). All variables which can have an effect on painful plantar heel spur in patients with plantar fasciitis were included in a multivariable logistic regression analysis. The analysis through this subgroup comparison identified high BMI as an independent risk factor of painful plantar heel spur. CONCLUSION: High BMI was the one single independent predictor of painful heel spur resulting in plantar fasciitis heel pain. Concerning the treatment for plantar fasciitis, we need to counsel patients on emphasizing protection and cushioning for plantar heel to relieve axial loading and weight loss to decrease BMI.