Ultrasound measurement of plantar fascia thickness: Is the current criterion for normality applicable to everyone?

BackgroundPlantar fasciitis is a common cause of heel pain. Understandably knowledge of normal sonographic plantar fascia thickness (PFT) is crucial to diagnose this condition as thickened plantar fascia is the most important ultrasound finding for its diagnosis.ObjectiveThe objectives of this study are to compare the PFT among heavy weight bearing and non-weight bearing individuals sonographically and to assess the effect of age, gender and body mass index (BMI) on PFT.MethodologyPFT of 154 patients, 77 in each category of heavy weight bearing and non-weight bearing groups, was assessed sonographically. Independent sample T test was used to compare it between two groups. Analysis of covariance was used to test the effect of heavy weight bearing and gender on PFT bilaterally, in both groups with adjustment for age, BMI and standing hours. Correlation of age with PFT was also calculated using Pearson's correlation analysis. p value & LE;0.05 was considered significant.ResultsMean PFT in all patients was 3.8 and 3.2 mm on left and right respectively. There was no significant difference in the right and left foot on paired sample t test. Those bearing heavy weight had significantly thickened PF than the other group bilaterally. ANCOVA showed that bearing heavy weight and BMI had significant effects on PFT. Age was found to be correlated with PFT in non-weight bearing group.ConclusionsFactors causing increased stress on the plantar fascia such as increased BMI and heavy weight lifting can cause thickening as part of physiological adaptation.