Intra- and Inter-Rater Reliability of Ultrasound in Plantar Fascia Thickness Measurement

Abstract

Background: Plantar fascia is a thick connective tissue on the plantar side of the foot, which provides the normal shape of the longitudinal arch. Plantar fasciitis is an inflammation on the medial tuberosity of calcaneus on the inferior side that may cause heel pain. Imaging plays an important role in the diagnosis of heel pain. Ultrasonography has been recognized as an effective imaging tool for assessing plantar fascia thickness, monitoring the effect of different interventions and guiding therapeutic interventions in patients with plantar fasciitis. Operator dependency is a major limitation for the common use of ultrasound. Objectives: The purpose of the present study was to evaluate intra and inter-rater reliability of ultrasound in measurements of the thickness of plantar fascia in different points of plantar fascia. Patients and Methods: Twelve healthy (without any lower extremity disorder) young (above 18) volunteers were recruited. Both heels were scanned in the sagittal plane by two raters. Subjects lied prone. Thickness of the plantar fascia was measured at the insertion point of the calcaneus, 5 and 10 mm from insertion of the calcaneus. For statistical analysis, intraclass correlation coefficients (ICC), 95% confidence intervals (CI), and linear mixed model ANOVA effects were run. Results: Our results showed that both intra and inter-rater reliability of plantar fascia thickness, measured by ultrasound, have high reproducibility (ICC > 0.821, ICC > 0.849). The linear mixed model suggested that neither rater nor time had a significant effect on the rater's measurements. Conclusion:The results of the present study indicate that both intra and inter-rater of measuring plantar fascia thickness at three points using ultrasound seemed to be high.

The EFSUMB Guidelines and Recommendations for Musculoskeletal Ultrasound – Part I: Extraarticular Pathologies

“…The relative reliability of thickness and echogenicity measurement of the plantar fascia was proven to be high (interclass correlation coefficient, ICC = 0.88) [401]. Good reproducibility was also found (intra-and interrater reliability, ICC > 0.821, ICC> 0.849) [402], as well as good agreement between an experienced and a novel sonographer [403]. In another study the intra-tester reliability was shown to significantly surpass the inter-tester reliability in plantar fasciitis (0.89 vs. 0.61, respectively) [404].…”

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

“…It is meant to provide stability and support to the medial arch of the foot and also acts as a dynamic shock absorber during walking and running. [1][2][3][4][5][6] Due to the constant exposure to mechanical load and trauma it is very prone to traumatic injuries, microtears and subsequent development of plantar fasciitis. [2][3][4][5][6][7] Plantar fasciitis is an idiopathic condition which is the most common cause of heel pain.…”

“…[1][2][3][4][5][6] Due to the constant exposure to mechanical load and trauma it is very prone to traumatic injuries, microtears and subsequent development of plantar fasciitis. [2][3][4][5][6][7] Plantar fasciitis is an idiopathic condition which is the most common cause of heel pain. According to the published reports it predominantly affects individuals between the ages of 40-60 years.…”

“…According to the published reports it predominantly affects individuals between the ages of 40-60 years. 4,5,[7][8][9] It is Authors have no conflict of interest to disclose.…”

“…7,10 Ultrasound although reported to be operator dependent is an easy, radiation free, cost-effective method, the applicability of which has already been established by many researchers. 3,4,9,11 The maximum limit of plantar fascia thickness (PFT) has been described by most of the researchers as 4 mm, above which the diagnosis of plantar fasciitis is made. 8,9 In order to diagnose plantar fasciitis in patients who carry heavy weight as a part of their work routine we need to have a definite knowledge of the normal PFT in symptom free individuals of this category.…”