ANA125 LE7: Posterior Compartment and Ligaments of the Ankle

attachment of anterior talo-fibular ligament

• distal fibula

• anterior talus

function of anterior talo-fibular ligament

resists inversion at subtalar joint with the talocrural joint in plantar flexion

attachment of posterior talo-fibular ligament

• distal fibula

• posterior talus

function of posterior talo-fibular ligament

resists inversion at subtalar joint w/ talocrural joint dorsiflexed

attachment of calcaneofibular ligament

• distal fibula

• calcaneus

function of calcaneofibular ligament

resists inversion at subtalar joint with talocrural joint in neutral

attachment of medial collateral ligament (deltoid ligament)

• distal tibia

• calcaneus

• navicular

• talus

function of medial collateral ligament (deltoid ligament)

resists eversion at subtalar joint with talocrural joint in all positions

attachment of long plantar ligament

• calcaneus

• metatarsal base 2-5

function of long plantar ligament

• supports bones

• make up medial and lateral arch

• absorbs shock/forces

attachment of short plantar ligament

• calcaneus

• cuneiforms

• navicular

function of short plantar ligament

stabilizes lateral arch

attachment of spring ligament

• calcaneus

• navicular

function of spring ligament

• stabilizes medial arch

• primary static stabilizer

• holds talus up

common action of tendons passing posterior to ankle

plantar flexion

common action of tendons passing anterior to ankle

dorsiflexion

common action of tendons passing behind lateral malleolus

eversion of subtalar and transverse joint

common action of tendons passing behind medial malleolus

inversion at subtalar and transverse joint

origin and insertion of gastrocnemius

origin: medial and lateral femoral condyles (posteriorly)

insertion: calcaneal tendon

action of gastrocnemius

• ankle plantarflexion

• knee flexion

origin and insertion of soleus

• origin: posterior tibia and head of fibula

• insertion: calcaneal tendon

actions of soleus

ankle plantarflexion

innervation of posterior and deep posterior compartment of the lower leg

tibial N

borders and content of popliteal fossa

borders

• superomedial: semimembranosus and semitendinosus

• superolateral: biceps femoris

• inferolateral: lateral gastrocnemius

• inferomedial: medial gastrocnemius

• floor: popliteus

content

• popliteal vessels

• tibial N

• fibular N

origin and insertion of plantaris

• origin: lateral femoral condyle posteriorly

• insertion: media calcaneal tendon

deep to gastrocnemius but superficial to soleus

actions of plantaris

weak plantarflexion of ankle

origin and insertion to popliteus

• origin: lateral femoral condyle posteriorly

• insertion: proximal tibia posteriorly

deep to all muscles in posterior compartment of the lower leg

actions of popliteus

starts knee flexion

origin and insertion of flexor digitorum longus

• origin: posterior tibia

• insertion: distal phalanges of toes 2-5

actions of flexor digitorum longus

• flexes PIP, DIP, MTP of digits 2-5

• plantarflexion of ankle

origin and insertion of flexor hallucis longus

• origin: posterior distal half of fibula

• insertion: distal phalange of 1st toe

actions of flexor hallucis longus

• flexion of IP and MTP of digit 1

• weak plantar flexion of ankle

origin and insertion of tibialis posterior

• origin: tibia, fibula, and interosseous membrane posteriorly

• insertion metatarsal and tarsal bones of digits 2-4

sandwiched between flexor digitorum longus and flexor hallucis longus

action of tibialis posterior

inversion of subtalar joint and plantarflexion of ankle

muscles of the deep posterior compartment

• flexor digitorum longus

• flexor hallucis longus

• tibialis posterior

muscles of the posterior compartment

• gastrocnemius

• soleus

• plantaris

• popliteus