The mechanics of the foot
from Journal of Anatomy
In a normal living foot that is weight-bearing, as in ordinary standing, passive extension of the big toe at the metatarso-phalangeal joint will be observed to result in the following effects: (i) the arch appears to rise; (ii) the posterior part of the foot assumes an 'inverted' position (supinates); (iii) the leg rotates laterally; (iv) there appears a tight band in the region of the plantar aponeurosis.
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