4.7 Muscles of lower leg

Question 2

What are the adductor muscles that cross the hip and knee joints

Answer 2

• 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

Question 3

Adductor magnus

Answer 3

*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

Question 4

Adductor longus

Answer 4

* 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

Question 5

Aductor brevis

Answer 5

*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

Question 6

Pectineus

Answer 6

*pecten = comb

• part of thigh adductors
• short, falt muscle that overlies the adductor brevis

O: pubis

I: femur

*adducts, flexes and medially rotates thigh

Question 7

Gracilis

Answer 7

• long , thin and superficial muscle of medial thigh

P: pubis

I: tibia

*adducts thigh, flexes and medially rotates leg *esp during walking

Question 8

What are the three muscle compartments involes into movements of ankles and toes

Answer 8

• anterior (skin, 4x muscles)

lateral (2x muscles)

posterior ( calf, 7x muscles)

• Fascia thickens distally ro form flesor, extensor and fibular retinacula

Question 9

What leg movements do the ankle, intertarsal joints and toes produce

Answer 9

Ankle: dorsiflexion and plantar flexion

Intertarsal joints: inversion and eversion

Toes: flexion and extension

Question 10

What muscles are found in the anterior compartment

(leg muscles involved in movement of ankle and toes)

Answer 10

* primary toe extensors and ankle dorsiflexors

includes:

tibilis anteror

extensor digitorum longus

fibularis tertius

extensor hallucis longus

Question 11

Tibialis anterior

Answer 11

*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)

Question 12

Extensor digitorum longus

Answer 12

O: tibia and fibula

I: second to fifth toes

*prime moer of toe extension

*dorsiflexes foot

Question 13

Fibularis tertius

Answer 13

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

Question 14

Extensor hallucis longus

Answer 14

* 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)

Question 15

Answer 15

Question 16

Answer 16

Question 17

What do muscles in the altearl compartment of leg do?

What muscles are in that compartment?

Answer 17

• plantar flextion and eversion of foot
• stablize lateral anklea dn alteral longitudinal arch of foor

Includes: fibularis longus and brevis

Question 18

Fibularis longus

Answer 18

aka fibularis peroneus longus

• superficial lateral muscle -> overlies fibula

O: fibula

I: first metatarsal

*pantarfelxes and everts foot

Question 19

Fibularis (peroneus) brevis

Answer 19

• smaller, deep to fibualris longus

O: fibula

I: fifth metatarsal

*plantar felxesa nd everts foot

Question 20

Answer 20

Question 21

Answer 21

Question 22

Role of muscles in the posterior compartment

Answer 22

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

Question 23

Tricpes surae

Answer 23

• 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

Question 24

Gastrocnemius

Answer 24

_ 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

Question 25

Soleus

Answer 25

- 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

Question 26

Plantaris

Answer 26

\* 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

Question 27

Answer 27

Question 28

Answer 28

Question 29

What are the deep muscles of the posterior compartment?

Answer 29

Popliteus flexor digitorum longus flexor hallus longus tibialis posterior

Question 30

Popliteus

Answer 30

\*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

Question 31

Flexor digitorum longus

Answer 31

\* 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

Question 32

Flexor hallucis longus

Answer 32

- 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

Question 33

Tibialis posterior

Answer 33

\* 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

Question 34

Answer 34

Question 35

Answer 35

Question 36

Answer 37