mid/forefoot Flashcards
function of talocalcaneonavicular (TCN) joint (This is a “virtual” joint)
produces pronation/supination
also does plantarflexion/dorsiflexion
transverse tarsal joint (functions as a unit)
talonavicular
calcaneocuboid
is the border for hindfoot and midfoor
action of transverse tarsal joint
adds supination/pronation ROM (helps you stand on a hill)
compensate forefoot/hindfoot position so forefoot can remain on ground
when the trasnverse tarsal joint supinates, what happens to the tarsals?
they go into a tight-packed position
midfoot and rearfoot lock on each other to act as a solid bone to assist propulsion!
what metatarsal joint is unique
the 2nd met - articulates with all 3 cuneiforms
it is the MOST stable tarsometarsal joint
function of tarsometatarsal joints
maintains contact of forefoot on the ground
if rear-foot motion (transverse tarsal and subtalar joints) are extreme, TMT can pick up the slack!
open chain actions of TMT (dorsfilexion)
extnesion and inversion of mets 1 and 2
eversion of mets 4 and 5
open-chain actions of TMT (plantarflexion)
flexion and inversion of mets 4 and 5
eversion of mets 1 and 2
closed chain action of TMT (supination twist).. when hind foot pronates
transverse tarsal joint supinates to end range
if this is insufficient, medial forefoot will press into ground resulting in dorsiflexion and inversion of 1st and 2nd mets.
then plantarflexion will happen? reuslting in 4 and 5 will invert
overall the ENTIRE FOOT INVERTS
closed chain action of TMT (pronation twist).. when hind foot supinates and midtarsal joint is locked
we end up with total eversion of mets 1,2,3,4 and some dorsiflexion of mets 4 and 5.
Whole forefoot EVERTs w/ pronation twist!
function of metatarsophalangeal joints
plantarflexion/dorsiflexion
abduction/adduction
major motion at metatarsophalangeal joints
plantarflexion/dorsiflexion dominate
when the 2nd met is the longest met, whats it called? exam
index minus
being index minus (elongated 2nd metatarsal) can result in
metatarsalgia, plantar warts, mallet toe
treat elongated 2nd metatarsal
use metatarsal pad, fit shoes for 2nd met, and avoid high heeled shoes.
what is morton’s foot
shortened 1st toe (its even shorter than your 3rd toe)
what can an elongated first metatarsal lead to?
hallux limitus deformity
treatment for hallux limitus defomirty (elongated first metatarsal)
kinetic wedge or a rocker bottom sole
a very sharp metatarsal break angle leads to
shifts weight laterally on the foot
typical range of metatarsal break angle
54 to 73 degrees
this reduces the extension range required for 1st and 2nd MTPs
function of great toe sesamoids
anatomic pulleys for FHb
acts as a tunnel to protect FHL tendon
purpose of interphalangeal joints
maintain contact with the ground just before toe off