Leg and Knee

Question 1

tibia vs fibula

Answer 1

tibia is larger, weight bearing and articulates w/ femoral condyles

fibula- smaller and more lateral, mainly for muscular attachment and ankle stabilization

Question 2

tibial tuberosity

Answer 2

attachment site for patellar tendon

Question 3

medial malleolus

Answer 3

medial projection of distal tibia

Question 4

anterior intercondylar area and posterior intercondylar area fn

Answer 4

ACL and PCL attachment

Question 5

describe knee joint structure

Answer 5

largest synovial joint but mechanically weak- needs lots of muscles and ligaments

primaryly hinge joint, although some gliding, rolling, rotation

Question 6

most important muscles for knee stabilization

Answer 6

quads

Question 7

patellar retinaculum

Answer 7

expansion of quad tendon around anterior aspect of knee

Question 8

ligaments helping strong fibrous capsule around knee

Answer 8

LCL
MCL
oblique popliteal (expansion of semimembranosus tendon)
arcuate popliteal (arches over popliteus)

LCL and MCL more clinically relevant

Question 9

LCL

Answer 9

from lateral femoral condylyle to head of fibula, easily palpable

Question 10

MCL

Answer 10

flat band like

deep fibers attached to medial meniscus

MCL and medial meniscus commonly injured simultaneously

Question 11

role of cruciate ligaments

Answer 11

join femur and tibia, added stability

Question 12

describe ACL role

Answer 12

slightly relaxed when knee is flexed, tighter when extended

prevents femur from sliding posteriorly on tibia and helps prevent knee hyperextension (injuries tend to happen in extended position)

Question 13

ACL rupture injuries, physical exam finding, concurrent terars

Answer 13

usually sports related w/ extension and over rotation

tibia can be manually displaced anteriorly, anterior drawer sign

often as unhappy triad- usually w/ tears of medial meniscus and MCL

Question 14

PCL role

Answer 14

tightens during knee flexion, prevents femur from sliding anteriorly on tibia

Question 15

menisci strucuture and fn

Answer 15

fibrocartilagenous plates on superior articular surface of tibia

shock asorbers, deepen joint cavity

Question 16

menisci injuries

Answer 16

usually during torsional twisting- limited blood supply so wont heal on their own

Question 17

contrast medial and lateral menisci

Answer 17

medial- larger and c shaped, attached to MCL fibers

lateral- smaller and circular, more mobile and therefore less likely to get injured and not fused to LCL (popliteus tendon is b/w these structures)

Question 18

PCL injuries

Answer 18

force on antior of tibia during flexion

Question 19

two main branches of sciatic nerve

Answer 19

tibial and common fibular

Question 20

contrast tibial and fibular nerves

Answer 20

tibial- thru popliteal fossa, innervates muscles in posterior compartment

common fibular- divides into superficial (lateral compartment) and deep (anterior compartment)

Question 21

3 main compartments of leg

Answer 21

anterior- deep fibular

lateral- superficial fibular

posterior (technically 2, superificial and deep)- tibial nerve

Question 22

superficial posterior muscles, fn

Answer 22

plantarflexors of ankle joint

gastrocnemius- 2 heads and crosses two joints, rapid plantar flexion

soleus- deep to gastroc, powerful but slow plantarflexor

plantaris- long thin tendon, maybe proprioception, used for grafts

tibial nerve S1,2 (S1 S2 I’m taller than you; help stand on toes)

Question 23

triceps surae

Answer 23

2 heads of gastroc and soleus muscle- has a common tendon forming achilles tendon inserting into calcaneal tuberosity

Question 24

deep posterior compartment muscles, fn

Answer 24

plantarflex the ankly, flex toes and invert foot

all innervated by tibial,

tibialis posterior- inserts into several pedal bones and support longitudinal arch, inversion of foot and plantarflexion

flexor digitorum longus- divides into 4 tendons w/i foot, inserts into base of distal planages and flexes toes

flexor hallucis longus- “push off” muscle, inserts distal phalanx and flexes big toe

Question 25

deep posterior muscles entry into foot

Answer 25

tendons pass trhur tarsal tunnel along w/ sciatic nerve

Question 26

Tom, Dick and Harry muscles and nerve roots of tibial nerve

Answer 26

tibialis posterior (L4,5), flexor digitorum longus (S2,3), flexor hallucis longus (S2,3)

Question 27

tarsal tunnel structures

Answer 27

from medial to lateral tom, dick AN' (posterior tibial Artery and tibial Nerve) harry underneath flexor retinaculum

Question 28

common fibular nerve branches into which compartments, sensory innervation

Answer 28

divides into branches after coursing around head of fibula superficial- lateral compartment, sensory to dorsum of foot deep fibular nerve- anterior compartment and sensory b/w big and second toe

Question 29

lateral compartment muscles

Answer 29

eversion of foot fibularis longus- tendon passes thru groove in cuboid, inserts into medial cuneiform and 1st metatarsal fibularis brevis- inserts base of 5th metatarsal superficial fibular nerve (L5, S1)

Question 30

anterior compartment muscles

Answer 30

dorsifexion of foot/toes tibialis anterior- powerful, primary dorsiflexor extendosr digitorum longus- extends digits, inserts into extensor expansion on toes, also dorsiflexes extensory hallucis longus- extends hallux, also dorsiflexion deep fibular nerve- L4,5 and S2 (fibularis tertius dorsiflexes and everts)

Question 31

neurovasculature of anterior compartment

Answer 31

deep fibular nerve and anterior tibial artery go b/w anterior compartment muscles, cross anterior to ankle and onto foot anterior tibial artery becomes dorsalis pedis artery, vascularize foot

Question 32

drop foot

Answer 32

anterior muscles weak or paralyzed- trauma to common fibular nerve or deep fibular erve or L4/5 disc herniation compensate w/ steppage gait- hyperflexion of the hip to raise foot during swing phase of gait, often w/ audible slap

Question 33

cause of common fibular nerve injury

Answer 33

fracture of head of fibula

Question 34

compartment syndrome

Answer 34

can happen in any muscular compartment- swelling compresses neurovasculature w/i compartment, causing diminished pulse, pain, extreme pain in anterior compartment muscles from trauma, overuse

Question 35

location of dorsalis pedis, patho

Answer 35

palpated lateral to EHL tendon, diminshed pulse can mean occlusive disease or anterior compartment syndrome

Question 36

ankle joint bones, stability

Answer 36

hinge synovial b/w distal tibia and fibula and the talus- distal tibia and fibula form a "mortise" for the trochlea of the talus anterior surface of trochlea is wider than posterior- more stable in dorsiflexion

Question 37

lateral ankle ligaments (3)

Answer 37

anterior talofibular*(most commonly injured during sprain) calcaneofibular posterior talofibular stabilize during inversion, 90 degrees apart and arise from distal fibula

Question 38

medial ankle ligaments

Answer 38

deltoid ligaments- stronger than lateral, stabilize during eversion and arise from medial malleolus stronger than bone, will evulse medial malleolus before tearing

Question 39

lateral ankle sprain

Answer 39

usually anterior talofibular, when pts land w/ foot plantarflexed and inverted talus becomes unstable w/i ankle mortise and easily twists or rolls, disrupting lateral ligaments