Muscle Quality Assessment by Ultrasound Imaging of the Intrinsic Foot Muscles in Individuals with and without Plantar Fasciitis: A Case–Control Study

Abstract

[EN] Objective: The primary aim of the present study was to compare the echo intensity (EI) andechovariation (EV) of the intrinsic foot muscles (IFMs) between individuals with and without plantarfasciitis (PF), using ultrasound imaging. The secondary objective was to study the intra-rater reliabilityof the echotexture variables. Methods: A case–control study was conducted with 64 participants,who were divided into the following two groups: A, the PF group (n = 32); B, the healthy group(n = 32). Results: The comparison between the two groups did not identify significant differences(p > 0.05) between the flexor hallucis brevis (FHB), flexor digitorum brevis (FDB), quadratus plantae(QP) and abductor hallucis brevis (AHB) variables for the EI and EV. Moreover, excellent intra-raterreliability was reported for the following ultrasound imaging EI variables: ABH (ICC = 0.951), FHB(ICC = 0.949), FDB (ICC = 0.981) and QP (ICC = 0.984). Conclusions: The muscle quality assessmentusing the EI and EV variables did not identify differences in the FHB, FDB, AHB and QP musclesbetween individuals with and without PF through USI evaluation. The reliability of all the IFMmeasurements was reported to be excellent.