4.7 Muscles of lower leg Flashcards
What are the adductor muscles that cross the hip and knee joints
- Adductors (also medially rotate thigh) used in movemnts that press thighs together
- overstrengthed thigh muscles often referred to as a pulled groin
include:
- Adductor magnus, longus and brevis
Pectineus
Gracilis
Adductor magnus
*Adduct: move twds midline, magnus: large
- triagnualr muscle w. broad insertion
O: ischial and pubic rami
I: femur
*anterior parts: adducts and medially rotates and flexes thigh
*posterior works with hamstrings in thigh extension
Adductor longus
* adductor of thigh
- overlies middle of adductor magnus
- most anterior of adductor muscles
O: pubis
I: linae aspera (femur)
*adducts, flexes and medially rotates the thigh
Aductor brevis
*brevis = short
- thigh adductor
- in contract w. obturator externus muscle, largely concealed by adductor longus and pectineus
O; pubic ramus
I: linea aspera (femur
*adducts, flexes and medially rotates thigh
Pectineus
*pecten = comb
- part of thigh adductors
- short, falt muscle that overlies the adductor brevis
O: pubis
I: femur
*adducts, flexes and medially rotates thigh
Gracilis
- long , thin and superficial muscle of medial thigh
P: pubis
I: tibia
*adducts thigh, flexes and medially rotates leg *esp during walking
What are the three muscle compartments involes into movements of ankles and toes
- anterior (skin, 4x muscles)
lateral (2x muscles)
posterior ( calf, 7x muscles)
- Fascia thickens distally ro form flesor, extensor and fibular retinacula
What leg movements do the ankle, intertarsal joints and toes produce
Ankle: dorsiflexion and plantar flexion
Intertarsal joints: inversion and eversion
Toes: flexion and extension
What muscles are found in the anterior compartment
(leg muscles involved in movement of ankle and toes)
* primary toe extensors and ankle dorsiflexors
includes:
tibilis anteror
extensor digitorum longus
fibularis tertius
extensor hallucis longus
Tibialis anterior
*muscles of anterior leg compartment
- superficial muscle of anterior leg
O: tibial shaft
I: first metatarsal bone
*prime mover of dorsiflextion (inverts foot, hekps support medial longitudional arch of foot)
Extensor digitorum longus
O: tibia and fibula
I: second to fifth toes
*prime moer of toe extension
*dorsiflexes foot
Fibularis tertius
small, usually cont and fused with distal part of extensor digitorum longus (not always presnt)
- O: distal anterior surface of fibula
- I: fifth metatarsal
*dorseflexes and everts foot
Extensor hallucis longus
* deep to extensor digitorum longus and tibialis anterior
O: fibula
I: great toe
*extends great toe and dorsiflexes foot
*part of anterior compartment of leg)
What do muscles in the altearl compartment of leg do?
What muscles are in that compartment?
- plantar flextion and eversion of foot
- stablize lateral anklea dn alteral longitudinal arch of foor
Includes: fibularis longus and brevis
Fibularis longus
aka fibularis peroneus longus
- superficial lateral muscle -> overlies fibula
O: fibula
I: first metatarsal
*pantarfelxes and everts foot
Fibularis (peroneus) brevis
- smaller, deep to fibualris longus
O: fibula
I: fifth metatarsal
*plantar felxesa nd everts foot
Role of muscles in the posterior compartment
act to plantar flex ankle all innervated by tibial nerve
Consists of:
superficial muscles : Triceps surae (gastrocnemius and soleus) and plantaris
Deep muscles: popliteus, flexor digitorum longus, flexor hallus longus and tibialis posterior
Tricpes surae
- part of posterior compantment of leg (superficial part)
- refers to muscle pair: gastrocnemius and soleus) both insert via common tendon into calcaneus of heel (achilles tendon, largest tendon in body)
*prime movers in plantar felxion
Gastrocnemius
_ part of triceps surae (posterior compartment of leg)
- superifcial, has two prominent bellies the form proximal curve of calf
O: two heads from femur
O: calcaneus
*plantar flexes foot, can also flex knee when foot dorsiflexed
Soleus
- part of triceps surae (superficial muscles of posterior compartment)
- deep to gastrocnmenius posterior to surface of calf
O: tibia, fibula
I: gastrocnemius
*plantar flexes foot, important for walking, running and dancing
Plantaris
* part of superficial muscles of posterior compartment of leg
*planta = sole of foot
- small muscle, may be absent
O; femur
I: calcaneus
*helps to felx elg and plantar flex foot
What are the deep muscles of the posterior compartment?
Popliteus
flexor digitorum longus
flexor hallus longus
tibialis posterior
Popliteus
*poplit = back of knee
*part of deep muscles of posterior compartment
0 thin muscle at posterior of knee
O: femur
I: tibia
*flexes and rotates leg medially to unlock extended knee when flexion begins
Flexor digitorum longus
* deep muscles of posterior compartment
- long and narrow, runs medial to and aprtially overlies tibialis posterior
O: tibia
I: second to fifth toes
*plantar flexes and inverts foot, flexes toes
Flexor hallucis longus
- deep muscle in posterior compartment
- lies lateral to inferior aspect of tibialis posterior
O: fibula
I: great toe
*plantar flexes and inverts foot, flexes great toe at all joints
Tibialis posterior
* part of deep muscles of posterior compartment
- thick and flat, deep to soleus, between posterior flexors
O: tibia and fibula
I: metatarsals II-IV
*prime mover of foot inversion, plantar flexes foot
