Contribution of Plantar Fascia and Intrinsic Foot Muscles in a Single-Leg Drop Landing and Repetitive Rebound Jumps: An Ultrasound-Based Study

Abstract

The plantar fascia and intrinsic foot muscles (IFM) modulate foot stiffness. However, it is unclear whether the corresponding ultrasonography findings reflect it. This study aimed to examine the effect of the plantar fascia and IFM morphologies on force attenuation during landing and reactivity when jumping in healthy adults (n=21; age, 21–27 years). Thickness, cross-sectional area (CSA), and hardness of the plantar fascia, abductor hallucis (AbH), and flexor hallucis brevis (FHB) muscles were measured using ultrasonography. Single-leg drop landing and repetitive rebound jumping tests assessed the ground reaction force (GRF) and reactive jump index (RJI), respectively. The CSA of FHB was negatively correlated with maximum vertical GRF (r = −0.472, p=0.031) in the single-leg drop landing test. The CSA of AbH was negatively correlated with contact time (r = −0.478, p = 0.028), and the plantar fascia thickness was positively correlated with jump height (r = 0.615, p = 0.003) and RJI (r = 0.645, p = 0.002) in the repetitive bound jump test. In multivariate regression analysis, only the plantar fascia thickness was associated with RJI (β = 0.152, 95% confidence interval: 7.219-38.743, p = 0.007). The CSA of FHB may contribute to force attenuation during landing. The thickness of the plantar fascia and CSA of AbH may facilitate jumping high with minimal contact time.

Supra-threshold vibration applied to the foot soles enhances jump height under maximum effort

“…However, most of the studies have focused on finger or hand-related movement [ 8 , 9 , 24 ]; whether a change in the amount of sensory input can also affect the maximal motor output of the whole-body movement remains to be clarified. Caminita et al showed that cooling-induced decrease in the sensitivity of the soles reduced the squat jump height [ 10 ], but it remains unclear how much of the reduction in the jump height results from the reduction in the sensory input rather than reduction in the dexterity of the plantar fascia and other toe-related muscles whose control is critical in the jumping motion [ 25 , 26 ]. More importantly, although previous studies have focused on decreased maximal motor output due to reduction in the sensory input, an increase in the motor performance under maximum effort due to any sensory input augmentation has been seldom investigated.…”

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

“…Other studies have shown that larger IFMs are related to a high maximum force and contact area of the foot, which are known to be found in foot disorders, such as PF [ 43 ]. Morikawa et al showed that the ultrasonography muscle architecture of the FHB and the plantar fascia were related to the force attenuation in the single-drop jump, and that the AHB and the plantar fascia were related to the repetitive rebound jump test [ 44 ]. These results suggest that changes in the muscles and soft tissues, developed by incorrect biomechanics of the ankle and foot, or heavy load fluctuations, may be observed using USI.…”

The Features of Foot Morphology and Intrinsic Foot Muscle Property in Adolescent Swimmers: An Ultrasound-Based Study

“…Finally, the probe was placed along a line between the third toe and the medial calcaneal tubercle to record the CSA image of the FDB, and was subsequently placed along the same line to record the thickness image (Taş et al, 2020). These measurement methods have been previously reported by our research group (Maeda et al, 2021;Morikawa et al, 2021), and they are reliable in assessing the IFMs thickness and the CSA (Crofts et al, 2014).…”