Anatomy: Leg & Foot Flashcards
What bone does the tibia articulate with distally?
talus
What are the features of the condyles of the tibia?
two facets (medial/lateral) Two intercondylar areas (for ACL/PCL)
What stabilizes the knee?
quadriceps muscle
patellar retinaculum
fibrous capsule
What makes up the fibrous capsule of the knee?
MCL
LCL
oblique popliteal ligament
arcuate popliteal ligament
What does the MCL attach to?
medial condyle
medial meniscus
tibia
Where does the ACL arise? PCL?
anterior intercondylar area
posterior intercondylar area
What position puts more tension of the ACL?
extension (standing)
What is the function of the ACL?
prevents posterior dislocation of femur from tibia (or anterior dislocation of tibia)
What is the unhappy triad?
ACL
medial meniscus
MCL
What is the anterior drawer sign?
ability to displace the tibia anteriorly after ACL injury
What position puts more tension on the PCL?
flexion (sitting)
What in the function of the PCL?
prevents anterior displacement of the femur or posterior displacement of the tibia
What are the menisci?
fibrocartilagenous circular plates on the tibia
What motion injures the menisci?
rotational injuries
What makes meniscus difficult to heal?
poor blood supply
Which meniscus has more mobility?
lateral
What sits between the LCL and lateral meniscus?
popliteus tendon
What are the three branches of the popliteal artery?
anterior tibial
posterior tibial
fibular
What does the tibial nerve innervate?
posterior compartments muscles
What does the superficial fibular nerve innervate?
lateral compartment
What does the deep fibular nerve innervate?
anterior compartment
What are the 4 leg compartments?
anterior
lateral
deep posterior
superficial posterior
What is the action of the superficial posterior muscles?
plantarflexion
What are the three superficial posterior muscles?
gastocnemius
soleus
plantaris
What is the triceps surae?
two heads of gastroc and soleus joining into one Achilles tendon
What nerve roots innervate the superficial posterior muscles?
S1-S2 (I’m taller than you)
What are the deep posterior muscles?
tibialis posterior
flexor digitorum longus
flexor hallucis longus
What is the action of the tibialis posterior?
plantarflextion
inversion
What vascularizes the knee joint?
genicular arteries
What passes through the tarsal tunnel (ant to post)?
tom dick artery nerve harry
What is the action of the lateral compartment muscles?
eversion
What are the two lateral muscles?
fibularis longus
fibularis brevis
What is the action of the anterior muscles?
dorsiflexion
What are the four anterior muscles?
tibialis anterior
extensor digitorum
fibularis tertius
extensor hallucis longus
What nerve and artery run through the anterior compartment?
deep fibular nerve
anterior tibial artery
What does the anterior tibial artery become?
dorsalis pedis
Where does the deep fibular nerve provide sensation?
between 1st 2 toes (flip flop)
What is a complication of fibular head fracture?
common fibular nerve damage (drop foot)
In what position is the ankle most stable?
dorsiflexion (anterior trochlea is wider)
What ligaments prevent inversion?
anterior talofibular
calcaneofibular
posterior talofibular
What ligaments prevent eversion?
deltoid ligaments
What are the 7 tarsals?
talus calcaneous navicular cuboid med/int/lat cuneiform
What causes talus fractures?
forced dorsiflexion
Where does the blood supply enter the talus?
neck (fractures lead to avascular necrosis)
What part of the calcaneous do you stand on?
calcaneal tuberosity
What is the function of the sustentaculum tali of the calcaneous?
supports the talus
FHL tendon runs under it as a fulcrum
What is a complication of a calcaneous fracture at the subtalar joint?
arthritis
What is a common MOI for a 5th metatarsal head fracture?
avulsion from inversion sprain
What is the name of the deep fascia on the bottom of the foot?
plantar fascia and plantar aponeurosis
What are the functions of the plantar aponeurosis?
protection of neurovasculature
arch support
muscular attachment
compartmentalization
What are the 4 foot compartments?
medial
lateral
central
interosseous
Where do the foot lumbrical muscles of the foot originate?
FDL tendons
In which later of the foot muscle is the neurovasculature?
second layer
What intrinsic muscles does the medial plantar nerve innervate?
flexor digitorum brevis
abductor hallucis
flexor hallucis brevis
1st medial lumbrical
What nerve roots innervate the foot intrinsic muscles?
S2-S3 (play footsie with me)
What are the two terminal branches of the tibial nerve?
medial and lateral plantar nerves
What does the medial plantar nerve innervate?
4 intrinsic muscles
sensory to distal medial foot and 3.5 toes (similar to median nerve)
What does the lateral plantar nerve innervate?
most intrinsic muscles
sensory to distal lateral foot and 1.5 toes (similar to ulnar nerve)
What are the two branches of the posterior tibial artery?
medial/lateral plantar arteries
What does the medial plantar artery vascularize?
medial foot and half of big toe
What does the lateral plantar artery vascularize?
everything else via the deep plantar arch (4.5 toes)
What actions occur in the subtalar joint?
inversion/eversion
What is the major ligament that stabilizes the subtalar joint?
interosseous talocalcaneal ligament
What is the transverse talar joint?
two joints:
calcaneocuboid
talonavicular
What ligament stabilizes the transverse talar joint?
bifurcate ligament
What are the three arches?
medial/lat longitudinal
transverse
What tendons support the arches? (4)
tibialis posterior
tibialis anterior
fibularis longus
flexor hallucis longus
What ligaments support the arches?
calcaneonavicular ligament (spring) long plantar ligament plantar aponeurosis
What is the most common cause of plantar fasciitis?
repetitive stretches and tears
Review Dr. K’s bottom line concepts for the foot
do it now
