Ankle and Foot Flashcards
Describe the motion of non-weight bearing pronation at subtalar joint.
DF, EV, ABD
Describe the motion of non-weight bearing supination at subtalar joint.
PF, INV, ADD
what is significant about the ankle mortise?
it is adjustable
talus is wider _____ than _____
anteriorly, than posteriorly
what is considered loose pack position of the ankle?
PF
what is the tibial torsion angle?
20-40 degrees of lateral rotation of the tibai
how many degres is the talus angled at in relation to horizontal?
14 degrees
what movement does the deltoid ligament prevent?
eversion and pronation
which capsule of the subtalar joint is the largest?
posterior capsule
the anterior and medial facets of the subtalar joint share capsules with which other joint?
talonavicular joint
what is calcaneovalgus the same as saying?
abduction (>180 degrees)
what is calcaneovarus the same as saying?
adduction (<180 degrees)
what motion is anterior talofibular ligament stressed with?
PF
what motion is calcaneofibular ligament stressed with?
INV
what motion is posterior talofibular ligament stressed with?
DF & INV
the posterior facet of the talocalcaneal joint transmits how much force?
75%
what is the strongest ligament of the subtalar joint?
cervical ligament
what is the subtalar joint axis relative to the horizontal?
16 degrees
what is the subtalar joint axis relative to the vertical?
42 degrees
what is the transverse tarsal joint formed by?
the talonavicular and calcaneocuboid ligaments
transverse tarsal joint motion occurs with the subtalar joint. T/F?
True
_____ head of talus supports _____ head of navicular bone.
convex, concave
what ligament is talonavicular joint supported by?
plantar calcaneonavicular ligament (spring)
what is the locked position at the subtalar joint?
supination
what is the loose packed position at the subtalar joint?
pronation
what happens at the transverse tarsal joint with supination?
supination
what happens at the transverse tarsal joint with pronation?
supination
what are the mechanical properties of pronation at the foot?
flexibility, shock absorption, allows accomodation to uneven surfaces
what are the mechanical properties of supination at the foot?
stability, makes foot rigid for propulsion
what does pronation facilitate at the tibia?
knee flexion
what does supination facilitate at the tibia?
knee extension
what is a supinated foot known as?
pes cavus
what is a pronated foot known as?
pes planus
excessive hindfoot pronation is called what at the forefoot?
forefoot varus
how many degrees of freedom does the MTP joint have and what are they?
2, PF, DF, ADD, ABD
what is the purpose of the sesamoid bone on the 1st MTP?
serves as an anatomic pulley for flexor hallucis brevis
define hallux rigidis.
limited extension of the 1st MTP
what is the normal walking angle of the toes for extension?
35-65 degrees
define hammer toe deformity.
extension of MTP, flexion of IP
in order to compensate for the increased ray angle causing hallux valgus, what occurs at the metatarsus?
metatarsus varus
what ligaments support the medial longitudinal arch?
short and long plantar ligaments, spring ligament, plantar aponeurosis
name the keystone of the longitudinal arch.
talus
name the keystone of the transverse arch (tarsal bone)
medial cuneiform
name the keystone of the transverse arch (metatarsal)
2nd metatarsal
where does the plantar aponeurosis attach?
proximal phalanx of each toe
what percentage of the body weight does plantar aponeurosis bear during gait?
96%
describe the windlass mechanism.
extension of the toe will cause supination of the foot (in order to protect the plantar aponeurosis)
all muscles of the ankle and foot cross how many joints?
2
what are the two most powerful PF?
gastoc and soleus
gasrocnemius pulls the calcaneus into what motion?
supination (can also help us move into pronation as well)
what two muscles have a long MA for supination?
gastrocnemius and tibialis posterior
action of Gastroc, flexor digitorum longus, and flexor hallucis longus
INV & PF
where does fibularis longus attach?
medial cuneiform
what subtalar motion is fib longus good for?
pronation
function of lumbricals and interossei.
flexion of MCP and extension of IP
what is the use of lumbricals and interossei?
prevents curling in of toes
