Lecture 10: Ankle and Foot Osteology (test 3) Flashcards
when walking and running describe the required stability of the foot
needs to be pliable to absorb impact and conform to surface
rigid enough to transfer forces
what is the talocrural joint
tibia + fibula + talus
“ankle” joint
what is considered the foot
all tarsal bones and joints distal to ankle
what are the 3 regions within the foot
rearfoor (hindfoot) = talus, calcaneus, and subtalar joint
midfoot = tarsal bones, transverse tarsal joint, and intertarsal joints
forefoot = metatarsals and phalanges with all tarsometatarsal joints
what are the osteologic similarities between the distal leg and the distal arm
radius and tibia each articulate with a set of small bones
7 small bones each (when pisiform is considered)
metatarsals and metacarpals are similar as well as the phalanges
thumb and great toe are NOT the same though
describe the fibula
long and thin
can palpate head
trasnfers 10% weight
forms lateral malleolus
articulate facet for talus
describe the distal tibia
broadens to transfer load
medial malleolus
articular surface for talus
fibular notch
twisted externally at longitudinal 20-30 degrees
describe the trochlear surface of the talus
rounded dome
convex AP
slightly concave ML
describe the projection of the talus
head projects forward and slightly medially
30 degrees medial to sagittal plane (40-50 with peds)
describe the facets of the talus
3 facets on the inferior surface (anterior, medial, and posterior)
facets form the subtalar joint with the calcaneus
the posterior medial groove of the talus is important for what purpose
acts for a pully for the FHL
describe the calcaneus
largest of the tarsals
impacts with heel strike
calcaneal tuberosity = achilles attachment
forms joints with cuboid and talus
has medial and lateral processes that are attachments for intrinsics and fascia
sustentaculum talus = horizontal shelf/middle facet for talus
the navicular bone forms joints with what bones
talus
3 cuneiforms
the navicular tuberosity is the attachment site for what muscle
posterior tibialis
importance of the medial, intermediate, and lateral cuneiforms
spacers between navicular and 3 metatarsal bones
contribute to the transverse arch
what are the articular surfaces of the cuboid
6 total
3 attachments with the tarsals
attachments to 4th and 5th metatarsals
the groove along the plantar surface of the cuboid is where what runs
peroneus (fibularis) longus
describe the metatarsals
5 linked tarsals and phalanges
2nd and 3rd are most rigidly connected
base facets are proximal, then shaft, then convex head distally
shaft is concave on plantar surface
1st has 2 sesamoid bones in FHL
5th has prominent styloid process (attachment for peroneus brevis)
describe the phalanges of the foot
14 total
4 have proximal/middle/distal components
great toe has proximal and distal