Ultrasonographic Evaluation of Plantar Fascia Thickness in Asymptomatic North Indian Adults: A Cross-sectional Epidemiological Study

Abstract Purpose: Every 10 th person, once in his lifetime, suffers from plantar fasciopathy. For the evaluation of plantar fasciopathy, ultrasound, being non-invasive and with very good sensitivity and specificity, has become the first line of imaging. To date, there is a paucity of data about plantar fascia thickness in the asymptomatic Indian adult population. The purpose of this prospective study was to generate normative data on plantar fascia thickness and its epidemiological variability in a statistically significant number for the asymptomatic Indian adult population. Methods: It was a cross-sectional epidemiological study at a tertiary care centre in northern India. The inclusion criteria included asymptomatic adults 18–65 years old and not having any pain around the heel on palpation. The exclusion criteria were acute heel trauma, any form of previous heel pain and previous surgery in the heel region. After informed consent from the subjects, the plantar fascia thicknesses were measured 0.5 cm distal to the point of calcaneal attachment through ultrasonography. SPSS software version 22 was used to conduct the statistical analyses. Results: Amongst 211 subjects (422 feet), fulfilling the eligibility criteria, 102 were male and 109 were female. The average thickness of plantar fascia in the population was 3.19 ± 0.61 mm; for male and female subjects, it was 3.30 ± 0.59 mm and 3.09 ± 0.53 mm, respectively; the left and right sides measured 3.20 ± 0.64 mm and 3.18 ± 0.57 mm, respectively. Males had a significantly higher mean than females ( P < 0.001), whereas the means for the right and left feet were comparable ( P = 0.271). Conclusion: The normal thickness of the plantar fascia as measured by ultrasound varies from study to study (range: 2.2–3.6 mm). In our study, we found it to be 3.19 ± 0.61 mm at 0.5 cm distal to the point of origin of the plantar fascia. A multivariate regression analysis of age, sex, height, weight and body mass index variables showed that only age was significantly linked to the thickness of the plantar fascia.