Muscles in the Leg Flashcards
how many muscles are in the anterior compartment of the leg?
4 muscles
what are the 4 muscles in the anterior compartment of the leg?
- tibialis anterior
- extensor digitorum longus
- extensor hallucis longus
- fibularis tertius
what are the origins and insertions of the extensor digitorum longus?
- origins - lateral condyle of tibia and medial surface of fibula
- inserts - tendon splits into 4 and inserts onto toes
what is the action of the extensor digitorum longus?
extension of the 4 toes and dorsiflexion of the foot
what is the strongest dorsiflexor of the foot?
tibialis anterior
what are the origins and insertions of the tibialis anterior?
- origins - lateral surface of tibia
- inserts - medial cuneiform and base of metatarsal I
what is the action of the tibialis anterior?
dorsiflexion and inversion of the foot
what are the origins and insertions of the extensor hallucis longus?
- origins - medial surface of fibular shaft
- inserts - base of distal phalanx of the great toe
what is the action of the extensor hallucis longus?
extension of great toe and dorsiflexion of the foot
all muscles in the anterior compartment of the leg are innervated by what?
deep fibular nerve (L4-S1)
all muscles in the anterior compartment of the leg receive their arterial supply from?
anterior tibial artery
what are the origins and insertions of the fibularis tertius?
- origins - extensor digitorum longus
- inserts - 5th metatarsal
what are the actions of the fibularis tertius?
eversion and dorsiflexion of the foot
what is ‘foot drop’?
- inability to dorsiflex foot at ankle
- usually due to damaged common fibular nerve
label the muscles of the anterior leg
label this muscle
what muscles are in the lateral compartment of the leg?
fibularis longus
fibularis brevis
the muscles of the lateral compartment of the leg are innervated by what?
superficial fibular nerve
what are the origins and insertions of the fibularis longus?
- origins - superior + lateral fibular and lateral tibial condyle
- inserts - attaches to the medial bones (cuneiform + base of metatarsal I)
what are the actions of the fibularis longus?
- eversion + plantar flexion of foot
- supports lateral + transverse arches
what are the origins and insertions of teh fibularis brevis?
- origins - inferolateral fibular shaft
- insertions - tubercle on 5th metatarsal
what are the actions of the fibularis brevis?
everts the foot
label the muscles of the lateral compartment of the leg?
the muscles in the posterior compartment of the leg are all innervated by what nerve?
tibial nerve
the muscles of the posterior compartment of the leg can be divided into what?
superficial and deep
what muscles are in the superficial posterior compartment of the leg?
- gastrocnemius
- plantaris
- soleus
what are the origins and insertions of the gastrocnemius?
- origin - lateral +medial femoral condyle
- inserts - converges with soleus to form calcaneal tendon that attaches to calcaneus
what are the actions of the gastrocnemius?
plantar flexion at ankle and flexion at knee joint
what are the origins and insertions of the plantaris?
- origins - lateral suprcondylar line of femur
- inserts - blends with calcaneal tendon and inserts on calcaneus
what are the actions of the plantaris?
plantar flexion at ankle joint + flexion at knee
what are the origins and insertions of the soleus?
- origin - soleal line of tibia + proximal fibula
- inserts - converges with gastrocnemius to form calcenal tendon and attaches to calcaneus
what are the actions of the soleus?
plantar flexion of foot at ankle joint
blood supply to the posterior compartment of the leg is mainly by what?
posterior tibial artery
what are the 4 muscles in the deep posterior compartment of the leg?
- popliteus
- tibialis posterior
- flexor digitorum longus
- flexor hallucis longus
what are the origins and insertions of the flexor digitorum longus?
- origins - medial surface of tibia
- inserts - plantar surfaces of lateral 4 digits
what are the actions of the flexor digitorum longus?
flexion of 4 lateral toes
what are the origins and insertions of the popliteus?
- origin - lateral condyle of femur and lateral meniscus of knee joint
- inserts - proximal tibia
what are the actions of the popliteus?
laterally rotates femus relative to tibia
whata re the origins and insertions of the tibilais posterior?
- origin - posterior surface of tibia and fibula
- inserts - plantar surface of medial tarsal bones
what are the actions of the tibialis posterior?
- inversion and plantar flexion of foot
- contributes to medial arch
what are the origins and insertions of the flexor hallucis longus?
- origin - posterior fibula
- inserts - plantar surface of phalanx of great toe
what are the actions of the flexor hallucis longus?
flexes big toe
label the deep muscles of the posterior compartment of the leg
label the superficial muscles of the posterior compartment of the leg