Lets take another look at yesterdays post “the Single leg squat” from a little different perspective….
Watch carefully. Did you pick up the bunion forming on both feet (Hallux Abducto Valgus)? This tells us that this individual has a faulty foot tripod, and is not able to get the base of the first metatarsal to the ground (remember the tripod is the base of the 1st metatarsal (big toe), the base of the 5th metatarsal (little toe) and the center of the heel). As a result, the muscles which are supposed to be assisting in forming the longitudinal and transverse arches are pulling the big toe (hallux) laterally. This also means that the medial side of the tripod is collapsing. This can be seen at :05 as she descends into the squat. You will also notice that this drives the knee medially and is causing some collapse of the arch. You also see the big toe flexing to try and create some arch stability through the flexor hallucis brevis.
As Dr Allen Points out, keeping the arch stable requires core stability, muscular strength and good proprioception. It also requires adequate flexibility (ie Range of Motion) of the 1st ray complex (the proximal and distal phalynx of the great toe and the 1st metatarsal). This range of motion can be seen from :12 to :20 and again from :42 to :51
Sorting through the subtle…We are The Gait Guys,
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