We hope you are thinking about muscles in a CLOSED CHAIN fashion, rather than open chain. In other words, when the foot is on the ground, it becomes the fixed point and the more proximal portion is the moveable portion. This paper shows (as Dr Allen did in his most excellent youtube video about foot function http://youtu.be/TyRE9dReVTE ) that the abductor hallicus is a dynamic elevator of the arch, in addition to being a great toe dorsiflexor and rear foot inverter!
Yup..we are definitely Gait Nerds….
