The plantar fascia as a strain gauge

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Might one of the major roles of the plantar fascia be that of a strain gauge to keep the CNS up to date with levels of stress being generated in the foot and lower limb during locomotion?

Consider the following quote from the paper referenced below (1) -

"There was a statistically significant correlation between the thicknesses of the PF and the paratenon. These findings suggest that the plantar fascia has a role not only in supporting the longitudinal arch of the foot, but also in its proprioception and peripheral motor coordination."

Yep .Back to proprioception .

Paper (1)
Plantar fascia anatomy and its relationship with Achilles tendon and ...

https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3842207/
by C Stecco - ‎2013 - ‎Cited by 70 - ‎Related articles
12 Sep 2013 - Analyzing its possible connections to the sural structures showed that this fascia is more closely connected to the paratenon of Achilles tendon

 

interesting idea
would be consistent with Luke Kelly's work on the plantar fascia

 

I wonder also if afferents from the plantar fascia contribute not only to the co-ordination of recruitment of the plantar intrinsics in the subject foot ,but also to muscular preparation in the contralateral foot .

In particular , the extent to which the " initial windlass phase of gait " is employed to reduce peak stresses in the plantar fascia of the contralateral foot during later weight acceptance ,might be dictated by the amount of dorsilflexion and thus "fascial wrap" introduced into that foot via toe dorsiflexor contraction . This would occur prior to foot contact and in response to afferents produced by fascial strain in the subject foot .

The more I read the more the short foot exercise begins to resemble a form of neuromuscular foot binding !

 

"would be consistent with Luke Kelly's work on the plantar fascia "
Good point .

It has been shown that humans adjust leg stiffness during running to accommodate to varying surface hardnesses and so maintain a consistent gait pattern . The foot ,of course , is and integrated part of this system but recent evidence (ref below Kelly et al 2014 ) suggests that the foot is not only part of a whole leg stiffness system but also has a closed tissue stress controlling system of its own .

In the paper mentioned , Kelly appears to shown that in seated subjects loading of the tissues of the foot (and in my view most likely loading of the plantar fascia ) produces an increasing amount of activity in the plantar intrinsics indicating a closed systems involving the plantar fascia and the intrinsic ,arch supporting muscles .

Thus , foot stiffness and leg stiffness can be controlled separately with the plantar fascia acting as a strain gauge in the case of the foot . Perhaps orthotics should be looked at from the perspective not only of how they affect the whole but also how they affect the systems within the foot .
Root came a long time before Kelly but I bet if he were starting of today his theories would be nothing like those attributed to him in the text books .

Intrinsic foot muscles have the capacity to control deformation of the ...

https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3928948/




by LA Kelly - ‎2014 - ‎Cited by 65 - ‎Related articles
8 Jan 2014 - The plantar intrinsic foot muscles possess origins and insertions that are ..... In this study, we have extended the findings of Kelly et al. [18] by ...