Lower leg and Ankle

Question 1

what type of joint is the proximal tibiofibular joint?

Answer 1

planar synovial joint

Question 2

what type of joint is the distal tibiofibular joint?

Answer 2

syndesmosis - not a synovial joint

Question 3

what prevents ankle adduction

Answer 3

medial malleolus and lateral (fibular) collateral ligaments

Question 4

what makes up the lateral (fibular) collateral ligaments

Answer 4

anterior and posterior talofibular ligament and calcaneofibular ligament

Question 5

What prevents ankle abduction

Answer 5

lateral malleolus and medial (tibial) collateral ligaments

Question 6

what makes up the medial collateral ligaments

Answer 6

anterior and posterior tabiotalar and tabionavicular ligaments

Question 7

when is the ankle most stable and why?

Answer 7

most stable during dorsiflexion b/c talus is trapezoid shape and during dorsiflexion the top 2 corners are locked between 2 malleolus

Question 8

what motions occur at the ankle?

Answer 8

dorsi and plantarflexion

Question 9

what motions occur at the intertarsal joints?

Answer 9

inversion and eversion

Question 10

muscles that pass over the ankle anteriorly do what motion?

Answer 10

dorsiflex

Question 11

dorsiflexion is achieved by what muscles?

Answer 11

extensor muscles innervated by posterior division nerve (fibular nerve)

Question 12

what motion is achieved at the intertarsal joint from muscles that go around the medial edge?

Answer 12

inversion

Question 13

what motion is achieved at the intertarsal joint from muscles that go around the lateral edge?

Answer 13

eversion - only done by fibularis muscles

Question 14

tibialis anterior

Answer 14

Proximal attachment – tibia, fibular, and interosseous membrane
Distal attachment – base of 1st metatarsal
Innervation - fibular nerve L4, L5 ventral rami
Action - inversion at intertarsal joint, dorsiflexion

Question 15

extensor digitorum longus

Answer 15

Proximal attachment – tibia, fibula, interosseous membrane
Distal attachment – extensor expansion 2-5
Innervation – fibular nerve L4, L5 ventral rami
Action – dorsiflex ankle, extend digits 2-5

Question 16

extensor hallucis longus

Answer 16

Proximal attachment – tibia, fibula, interosseous membrane
Distal attachment – extensor expansion
Innervation – fibular nerve L4, L5 ventral rami
Action – dorsiflex ankle, invert, extend digit 1 (done when you swing so you don’t drag your big toe while walking)

Question 17

fibularis tertius

Answer 17

Proximal attachment – fibula
Distal attachment – base of 5th metatarsal
Innervation – fibular nerve L4, L5 ventral rami
Action – dorsiflex at ankle, evert at intertarsal joint

Question 18

what prevents bowstringing at angle

Answer 18

superior/inferior extensor/fibular retinaculum

Question 19

fibularis longus

Answer 19

Proximal attachment – fibula
Distal attachment – base of metatarsal 1 and 1st (medial cuneiform)
Innervation – superficial fibular nerve L5, S1, S2
Action - plantarflexion (cross posterior to lateral malleolus), evert at intertarsal joint and also maintains transverse arch at intertarsal joint

Question 20

fibularis brevis

Answer 20

Proximal attachment – fibula
Distal attachment – base of metatarsal 5 (same as tertius)
Innervation – superficial fibular nerve L5, S1, S2
Action - plantarflexion (cross posterior to lateral malleolus), evert at intertarsal joint

Question 21

what is the gastroc so powerful?

Answer 21

anaerobic muscle - powerful but has a short life span

Question 22

what muscle is used for walking and long distance running and why?

Answer 22

soleus b/c it is aerobic

Question 23

gastrocnemius

Answer 23

Proximal attachment – medial and lateral condyle of femur
Distal attachment – heal through achilles tendon
Innervation – tibial nerve S1, S2
Action – flex knee (synergize w/ hamstrings), plantarflex at ankle

Question 24

soleus

Answer 24

Proximal attachment – tibia, fibula, interosseous membrane
Distal attachment – calcaneus (Achilles) tendon
Innervation – tibial nerve S1, S2
Action – plantarflex at ankle

Question 25

popliteus

Answer 25

Proximal attachment – lateral condyle
Distal attachment – tibia, runs through joint capsule
Innervation – tibial nerve L4, L5, S1
Action – flex at knee, main function is to external rotate femur and internally rotate tibia – counter rotate tibia and femur to unlock knee during walking phase – counter rotation to unlock the knee

Question 26

what is main function of popliteus

Answer 26

rotate femur laterally at knee to “unlock” from full extension

Question 27

tibialis posterior

Answer 27

Proximal attachment – tibia, fibula, interosseous membrane
Distal attachment – calcaneus, cuboid, cuneiform, and bases of middle metatarsals 2-4
Innervation – tibial nerve L4, L5
Action – plantarflex at ankle, invert at intertarsal joints, maintains transverse arch at intertarsal joints like fibularis longus

Question 28

flexor hallicis longus

Answer 28

Proximal attachment – fibula and interosseous membrane, and tibia – more lateral posterior leg
Distal attachment – digit 1 distal phalange
Innervation – S2, S3
Action – plantarflex at ankle, flex digit 1 (toe off when you walk), invert at intertarsal

Question 29

flexor digitorum longus

Answer 29

Proximal attachment – medial posterior side of leg – tibia, fibula, interosseous membrane
Distal attachment – distal phalange of digits 2-5
Innervation – S2, S3
Action – plantarflex at ankle and flex digits 2-5, invert at intertarsal

Question 30

boundaries of popliteal fossa

Answer 30

1. superior lateral = biceps femoris
2. superior medial = semitendinosus and semimebranosus
3. inferior lateral and medial = gastrocnemius

Question 31

contents of popliteal fossa

Answer 31

popliteal artery and vein, small saphenous vein, tibial and fibular nerve (sciatic), popliteus muscle