Biomechanics of HAV Flashcards
abduction and adduction of the lesser toes caused by the interossei uses what as a reference line?
utilizes 2nd toe as midline reference point
the lumbricals use what as their reference point fo rmidline?
midline of the body
in which direction does the great toe move if it were abducting?
moves away from the midline of the body (but towards the 2nd toe)
what does the great toe utilize as its midline?
midline of the body
which muscle causes abduction of the great toe?
adductor hallucis
in which direction does the great toe move if it were adducting?
towards the midline (or away from the 2nd toe)
which muscles causes adducting of the great toe?
abductor hallucis
therefore the names of abductor hallucis and adductor hallucis utilize what reference ilne?
2nd toe as midline
what is the primary etiology of HAV?
STJ pronation
how does pronation lead to HAV?
-as the arch lowers and cuboid dorsiflexes, it loses its ability to act as a fulcrum for peroneus longus to plantarflex the 1st met
what is a Lapidus procedure?
fusion of 1st met-cueniform joint
what movement does the 1st met have when it is dorsiflexing?
it also inverts
in which planes of deformity is HAV?
frontal plane (valgus) ; transverse plane (abduction)
what action does the 1st lumbrical have?
adducts the 2nd toe
what is Stage 1 of a bunion deformity characterized by?
lateral subluxation of base of proximal phalanx away from the 1st metahead
*and 1st met dorsiflexes and inverts