LAB 4: Lower limbs

Question 1

pelvic girdle & lower limb

Answer 1

• os coxae: ilium, ischium, & pubis
• sacrum
• coccyx
• pelvic brim- giant hole in pelvic girdle
• upper region- false pelvis
• lower region- true pelvis

Question 2

iilum

Answer 2

• makes up iliac crest
• two anterior bumps (superior and inferior) ->
• anterior superior iliac spine
• anterior inferior iliac spine
• articulates with pubic bone
• iliac fossa (iliacic muscle attacked here)

Question 3

pubic bone

Answer 3

-articulates with pubis
-roughened bone -> pubic tubercle- attachment site for inguinal ligament
-

Question 4

obturator foramen

Answer 4

• passage of blood vessels and nerves
• hole
• muscle located in it
• obturator externis
• obturator internis

Question 5

acetabulum

Answer 5

• allows head of femur to articulate with hip bones

- face laterally

Question 6

pubic symphysis

Answer 6

• subpubic angle- arch of the bottom of the pelvic girdle

- by the pubic symphysis

Question 7

subpubic angle

Answer 7

• narrow for males
• broad for females
• arch of the bottom of the pelvic girdle
• by the pubic symphysis

Question 8

how do you know if your looking at the lateral view of an os coxae

Answer 8

• you can see the acetabulum
• ischial spine is posterior
• greater sciatic notch is posterior

Question 9

sacrospinous ligament

Answer 9

-attaches to sacrum and ischial spine

Question 10

sacrotuberous ligament

Answer 10

-between ischial tuberosity and sacrum

Question 11

greater sciatic notch

Answer 11

-forms the greater sciatic foramen from the sacrospinous ligament

Question 12

lesser sciatic notch

Answer 12

-forms the lesser sciatic foramen from the sacrotuberous ligament

Question 13

femur

Answer 13

• long neck
• greater trochanter- attachment for lateral rotators from gluteal region
• lesser trochanter
• intertrochanteric crest -> separates the greater and lesser trochanter
• linea aspera- posterior, attachment site for adductor muscles in medial thigh
• lateral and medial epicondyle

Question 14

patella

Answer 14

• sesamoid bone- enclosed in an tendon (quadriceps tendon)

- attach to tibia by changing its name from quadriceps tendon to patellar ligament

Question 15

quadriceps tendon

Answer 15

• patella is enclosed in this

- turns into the patellar ligament as it attaches to tibial tuberosity

Question 16

tibia

Answer 16

• intercondylar eminence- between the condyles
• medial and lateral condyles
• medial malleolus- protrudes inferiorly (medial ankle bump)
• medial

Question 17

fibula

Answer 17

• lateral mallelous- lateral bump on the ankle
• neck
• head
• lateral

Question 18

foot

Answer 18

• tarsals- 7- calcaneus, talus, cuboid, navicular, medial, middle, lateral cuneiforms
• metatarsals- 5
• phalanges- 14

Question 19

calcaneus

Answer 19

• heel

- Achilles (calcaneal) tendon attaches here

Question 20

talus

Answer 20

• articulate with tibia and fibula
• talocrual joint
• dorsi and plantar flex

Question 21

proximal row of tarsals

Answer 21

• calcaneus
• talus
• navicular

Question 22

distal row of tarsal

Answer 22

• cuboid
• medial cuneiform
• intermediate cuneiform
• lateral cuneiform

Question 23

Tiger Cubs Need MILC

Answer 23

• proximal to distal row
• talus, calcaneus, navicular
• MILC- medial to lateral
• medial cuneiform, intermediate cuneiform, lateral cuneiform, cuboid

Question 24

longitudinal and transverse arch

Answer 24

• medial longitudinal arch
• mostly formed by calcaneus & navicular
• spring ligament- from sustantaculum tali (On calcaneus) to plantar surface of navicular -> helps support the arch
• *plantar aponeurosis (fascia)- from calcaneus to base of proximal phalanges -> taught band that helps maintain the arch

Question 25

planar aponeurosis (fascia)

Answer 25

- large dense - from calcaneus to base of proximal phalanges - taught band that helps maintain the arch

Question 26

acetabular labrum

Answer 26

-

Question 27

lunate surface

Answer 27

-half ring that lines acetabulum

Question 28

extracapsular ligaments

Answer 28

- provide support - ischiofemoral ligament - iliofemoral ligament - pubofemoral ligament

Question 29

transverse acetabular ligament

Answer 29

-weak point in the hip -closes the circle inferiorly -

Question 30

ligamentum teres

Answer 30

- inside joint capsule - from fovia capitis and attaches to acetabulum - artery to the head of the femur- inside the ligament

Question 31

knee

Answer 31

- synovial - between condyles there is a disc -> meniscus -> medial and lateral - ACL attaches to medial meniscus

Question 32

knee ligaments

Answer 32

- medial collateral ligament (MCL)- stabilizes medial side -> prevents excessive adduction - MCL attached to medial meniscus - lateral blow may tear MCL - lateral collateral ligament (LCL)- stabilizes lateral side -> prevents excessive abduction - medial blow will tear LCL

Question 33

intracapsular ligaments of knee

Answer 33

- anterior cruciate ligament (ACL)- femur to anterior tibia -> prevents anterior dislocation of tibia - ACL inserts directly onto medial meniscus -> if you tear ACL you can also pull medial meniscus with it - posterior cruciate ligament (PCL)- femur to posterior tibia

Question 34

anterior drawer test

Answer 34

- sit down - legs handing - pulls forward - if tibia comes forward too much -> torn ACL

Question 35

unholy triad

Answer 35

- lateral blow - tears MCL - tears medial meniscus - ACL is attached to medial meniscus too -> tears ACL too

Question 36

ankle joint: talocrural joint- plantar/dorsiflexior

Answer 36

- tibia, fibula, and talus | - deltoid ligament (med) & lateral collateral ligament (lat)

Question 37

ankle joint: subtalar joint- inversion/eversion

Answer 37

-talus articulates with calcaneus

Question 38

ankle joint: transverse tarsal joint- inversion/eversion

Answer 38

- talus articulates with navicular | - calcaneus articulates with cuboid

Question 39

spring ligament

Answer 39

-reinforce subtalar & transverse tarsal joints

Question 40

femoral nerve

Answer 40

- anterior compartment of thigh | - comes through L2-L4

Question 41

obturator nerve

Answer 41

- medial compartment of thigh | - comes through L2-L4

Question 42

L4-S3

Answer 42

- N. to obturator internus - N. to quadratus femoris - superior gluteal n. - inferior gluteal n. - sciatic nerve: includes: tibial n and common fibular n

Question 43

anterior/lateral compartment

Answer 43

- femoral n- anterior - guteal n- lateral - common fibular n- anterior/lateral - deep and superficial fibular nn. -> deep goes to anterior leg -> superficial goes to lateral

Question 44

lumbosacral plexus

Answer 44

-inside pelvis

Question 45

posterior/medial compartment

Answer 45

- obturator n-medial -> adductor - tibial n. -posterior - medial and lateral plantar n

Question 46

iliopsoas (iliacus +psoas major)

Answer 46

- origin (iliacus) - iliac fossa - origin (psoas major)- lumbar vertebrae - insert- lesser trochanter - action- flex hip and flex trunk - innervate- femoral nerve - start separate and then join

Question 47

gluteus maximus

Answer 47

- origin- posterior ilium, sacrum and coccyx - inserts- gluteal tuberosity and ITB - action- extend hip and lateral rotation of hip - innervation- inferior gluteal n

Question 48

gluteus minimus

Answer 48

- origin- outer surface of ilium - insert- greater trochanter of femur - action- abduct hip and medial rotation - innervates- superior gluteal n

Question 49

tensor fasciae latae

Answer 49

- origin- anterior iliac crest - inserts- ITB (lateral tibial condyle) - action- flex hip and abduct hip - innervates- superior gluteal n

Question 50

gluteus medius

Answer 50

- origin- outer surface of ilium and iliac crest - insert- greater trochanter of femur - action- abduct hip and medial rotation -> stability of hips during gait - innervations- superior gluteal n

Question 51

gluteals

Answer 51

- gluteus maximus - gluteus minimus - tensor fasciae latae - gluteus medius

Question 52

flex hip

Answer 52

= flex thigh

Question 53

deep lateral rotators

Answer 53

- lateral rotators/deep gluteal region - piriformis - obturator internus - gemellus superior - gemellus inferior - quadratus femoris - obturator externus - Action- lateral rotation of thigh - innervate- nerve to piriformis-piriformis, nerve to obturator internus-obturator internus and superior gemellus, nerve to quadratus femoris-quadratus femoris and inferior gemellus

Question 54

piriformis

Answer 54

- largest of the deep gluteals, run through greater sciatic notch to greater trochanter - lateral rotator - nerve to piriformis- piriformis

Question 55

anterior compartment of thigh

Answer 55

- ALL innervated by femoral n - sartorius - rectus femoris - vastus lateralis, vastus medialis & vastus intermedius

Question 56

sartorius

Answer 56

- origin- inferior to ASIS (anterior superior iliac spine) - insert- medial condyle of tibia - action- flexion and lateral rotation of thigh and flexion and medial rotation of leg; weak hip abduction

Question 57

rectus femoris

Answer 57

- part of quadriceps - crosses hip (anterior) and knee joint (anterior) - origin- AIIS (anterior inferior iliac spine) - insert- tibial tuberosity via patellar tendon - action- flex hip and extend knee

Question 58

femoral nerve

Answer 58

- ends up on anterior side of thigh | - however it is a dorsal nerve

Question 59

sciatic n

Answer 59

- tibial n- posterior leg (ventral division) | - common peroneal n- anterior leg (dorsal division)

Question 60

4 quadricep muscles...how many cross the knee joint

Answer 60

- all - all insert via quadriceps tendon - all extend knee - rectus femoris is the ONLY one that also crosses hip joint

Question 61

vastus lateralis, vastus medialis & vastus intermedius

Answer 61

- origin (vasti)- proximal femur | * ****

Question 62

medial compartment of thigh

Answer 62

- all originate on pubic (except adductor magnus -> ischiopubic ramus) - all insert onto femur (except gracilis -> proximal tibia) - all ADDUCT the thigh - all innervated by obturator n - pectineus- femoral n* - H/S part of adductor longus- tibial n*

Question 63

adductor magnus

Answer 63

``` TOP HALF: -medial compartment -adductor -innervated by obturator n -from pubic bone to posterior shaft of femur -adductor portion BOTTOM HALF: -ischiocondylar part -hamstring part -inserts on adductor tubercle -posterior nerve innervation -> tibial n. ```

Question 64

posterior compartment of thigh

Answer 64

- hamstrings - originate from ischial tuberosity (except short head of bicep femoris -> posterior femur) - majority innervated by tibial n. (except short head -> common fibular n.) - ALL flex the knee and majority extend the hip (short head does NOT extend hip)

Question 65

anterior compartment of leg

Answer 65

- ALL innervated by deep fibular n - tibialis anterior- dorsiflexes and inverts foot - extensor hallucis longus- extendss 1st digit and inverts foot - extensor digitorum longus-extends digits 2-5 and everts foot - fibularis tertius- dorsiflexes and everts foot

Question 66

lateral compartment of leg

Answer 66

- fibularis longus and fibularis brevis - origin- fibular shaft - insert- both wrap posteriorly to lateral malleolus - brevis- base of 5th metatarsal - longus- crosses plantar surface to 1st metatarsal - action- plantarflex and evert foot

Question 67

posterior compartment of leg

Answer 67

- all innervated by tibial n and ALL plantar flex the foot - superficial layer- all insert onto calcaneal tuberosity - these muscles are bigger bc they plantarflex -> propel your whole body forward - gastrocnemius - soleus - plantaris - tibialis posterior- plantar flexes and inverts foot - flexor digitorum longus- plantarflex foot and flex digits 2-5 - flexor hallucis longus- plantarflexes foot and flex digit 1

Question 68

gastrocnemius

Answer 68

- origin- medial and lateral femoral condyles - action- plantarflexes foot and flexes knee - posterior compartment of leg

Question 69

soleus

Answer 69

- origin- soleal line of tibia - action- plantarflexes foot - posterior compartment of leg

Question 70

plantaris

Answer 70

- origin- supracondylar ridge of femur - action- plantarflexes foot - posterior compartment of leg

Question 71

tarsal tunnel*

Answer 71

-anterior to posterior -tom dick and nervous harry Flexor Hallucis Longus, Flexor Digitorum Longus, Tibialis Posterior, Tibial Nerve, and Posterior Tibial Artery -know which is nerve and artery TEST

Question 72

intrinsic foot muscles

Answer 72

- dorsal compartment - extensor digitorum brevis (only dorsal muscle of foot) - extensor hallucis brevis splits off to form won muscle belly and tendon - extends big toe

Question 73

intrinsic foot muscles: plantar compartment

Answer 73

-innervated by medial

Question 74

common iliac artery

Answer 74

- two on each side - go toward pelvis - split into internal and external iliac artery - once external iliac artery passes inguinal ligament it changes its name into femoral artery

Question 75

femoral artery

Answer 75

- goes through adductor canal - goes to popliteal fossa - once it goes to popliteal fossa it becomes popliteal artery

Question 76

popliteal artery

Answer 76

- splits into posterior and anterior tibial artery - anterior tibial artery- gives off dorsalis pedis at foot - posterior tibial artery- gives off fibular artery and med and lat plantar artery

Question 77

ischial tuberosity

Answer 77

-hamstrings attach

Question 78

pelvic girdle

Answer 78

- sacrum - coccyx - and left and right os coxae

Question 79

os coxae

Answer 79

- links the free part of the lower limb and the axial skeleton - large, irregular shaped - aka innominate - consists of 3 bones - ilium- superior - ischium- posterior - pubis- anterior - prior to fusion these bones are separated by triradiate cartilage in the acetabulum - pubis and ischium are separated by cartilage below the large obturator foramen - articulates with ala of the sacrum by the large ear-shaped auricular surface posteriorly -> bounded anteriorly and posteriorly by strong sacroiliac ligaments - os coxae articulate with each other anteriorly in the midline at the cartilaginous pubic symphysis

Question 80

obturator foramen

Answer 80

-covered by a tendinous membrane

Question 81

iliac crest

Answer 81

- superior margin of the os coxae | - projects ventrally as the anterior superior iliac spine

Question 82

ischial spine

Answer 82

- below the auricular surface - prominent - ischium broadens inferiorly and laterally as the ischial tuberosity

Question 83

greater/lesser sciatic notch

Answer 83

- between the auricular surface and the ischial spine - deep - between the ischial spine and the ischial tuberosity is the shallow lesser sciatic notch - ligaments stretch across the posterior margins of both notches, transforming them into foramina

Question 84

superior ramus of the pubis

Answer 84

- forms a sharp crest (pecten pubis) - runs posteriorly from near the symphysis to the ilium - the line of the crest continues on the inner surface of the ilium as a ridge to the sacroiliac joint-> arcuate line - pecten pubis and arcuate line separate the pelvis into 2 parts: false pelvis above and true pelvis (obsterical pelvis) below

Question 85

arcuate line

Answer 85

- the line of the crest continues on the inner surface of the ilium as a ridge to the sacroiliac joint-> arcuate line - pecten pubis and arcuate line separate the pelvis into 2 parts: false pelvis above and true pelvis (obsterical pelvis) below

Question 86

femur

Answer 86

- hemispherical head- proximal end - head articulates in the acetabulum of the os coxae - neck- connects head and shaft - greater trochanter- at the top of the junction of the neck and shaft -> has a deep fossa on its medial side - lesser trochanter- projects medially form the back of the shaft where it meets the neck - intertrochanteric crest- ridge on the back of the shaft where the trochanters are connected - gluteal tuberosity- roughened area lateral to the trochanter - linea aspera- prominent ridge that the gluteal tuberosity continues down the back of - lateral/medial condyle- distal end, articulate with the proximal end of the tibia -> condyles are separated posteriorly - patellar surface- anteriorly the condyles merge into this; spool shaped; where the patella glides - lateral/medial epicondyle- expanded distal epiphysis above the articular surface

Question 87

linea aspera

Answer 87

- prominent ridge that the gluteal tuberosity continues down the back of - the medial and lateral margins of the linea aspera diverge distally around the slightly concave popliteal surface

Question 88

patella

Answer 88

- triangular - sesamoid bone - forms in the tendon of the quadriceps femoris - most of its posterior surface articulates with the patellar surface of the femur

Question 89

leg

Answer 89

-comprises of tibia (medial) and fibula (lateral)

Question 90

tibia

Answer 90

- tibial plateau- expanded proximal end that articulates with the femur by the medial and lateral condyle - intercondylar eminence- separate the medial and lateral condyle in the center of the plateau - shaft is triangular in cross section - anterior edge- shin - quadriceps femoris- tendon of this muscle attaches attaches at a roughened tuberosity of the front of the shaft below the plateau - medial malleolus- bone that projects medial and laterally - talus- articulates with the distal surface of the tibia and with the lateral surface of the medial malleolus

Question 91

fibula

Answer 91

- head- expanded proximal end that articulates with a facet on the tibia just below its lateral condyle - shaft is very slender bc the bone bears practically no weight - lateral malleolus- slightly enlarged distal end that is held tightly against a notch in the tibia by ligaments; medial surface articulates with talus

Question 92

foot

Answer 92

- 26 bones - tarsals- 7 -> ankle, heel - metatarsals- 5 -> sole of foot - phalanges-14 -> toes - phalanges and associated metatarsal form a ray - rays- 1-5 from big to little toe

Question 93

proximal tarsals

Answer 93

- talus - calcaneus - navicular - talus and calcaneus are the largest and most irregular shaped bones

Question 94

talus

Answer 94

- spool-shaped superior surface - articulates with the distal end of the tibia and the medial and lateral malleoli of the tibia and fibula - ankle joint permits the foot to be plantarflexed and dorsiflexed - talus sits atop the calcaneus and articulates anteriorly with the navicular

Question 95

calcaneus

Answer 95

- articulates superiorly with the talus - subtalar joint allows the foot to be inverted and everted - articulates anteriorly with the cuboid bone - posterior half of the calcaneus is expanded into a tuberosity (the heel) that makes initial contact with the ground (heel strike) during walking and running - also serves as the attachment of the large calf muscles by the achilles tendon

Question 96

navicular

Answer 96

- elliptical bone - concave proximal surface that articulates with the talus and a convex distal surface that articulates with each of the 3 cuneiform bones

Question 97

cuboid

Answer 97

- 4 distal bones - cuneiforms- medial, intermediate, lateral - form a row that articulates with the metatarsals

Question 98

metatarsals

Answer 98

- 5 - form most of the sole - the first element of each ray (phalange of each toe and the metatarsal associated) is its metatarsals - proximal end is expanded to form a base that articulates with one or more of the tarsal bones - distal end forms a rounded head that articulates with a proximal phalanx - first (big toe) metatarsal is very robust - other four are long and slender

Question 99

phalanges

Answer 99

- 14 - toes - each of the four lateral toes has a proximal phalanx, middle phalanx, and distal phalanx - big toe=hallux - big toe only has proximal and distal phalanx - hallucial phalanges are notably the most robust bc the big toe is very important weight-bearing element during walking and running

Question 100

plantar arch

Answer 100

- human foot - resists the pressures of deformation that are generated during walking and running - during support phase the body weight is borne by the front foot -> dorsiflexion -> possible due to the arch

Question 101

longitudinal arch

Answer 101

- runs along the medial side of the foot between the tuberosity of the calcaneus (the heel) and the metatarsal-phalangeal joint (the ball) - transverse arch is a by product of this longitudinal arch -> its higher medially than laterally

Question 102

arch

Answer 102

-maintained by the shape and fit of the bones, the ligaments that bind the tarsal bones, and the plantar aponeurosis (also some intrinsic muscles)

Question 103

arch: bones

Answer 103

- arch is maintained by shape and fit of bones - talus is a keystone -> wedged between calcaneus and navicular - back of arch is formed by the calcaneus - front of arch is formed by the navicular, 1 of 3 cuneiforms (medial), and the more medial metatarsals (first)

Question 104

arch: ligaments

Answer 104

- maintains arch - body weight goes to talus -> ligaments prevent collapse - provide rigid structure - capable of some degree of movement - spring ligament- (aka plantar calcaneal-navicular ligament) arises from the edge of a medially projecting shelf of bone from the calcaneus (sustentaculum tali), runs underneath the talus, and inserts onto the mavicula

Question 105

arch: plantar aponeurosis

Answer 105

- deep to the superficial fascia of the sole of the foot - arises from the tuberosity of the calcaneus, and fans out to insert onto the base of the proximal phalanx of each toe - tightened as the toes are dorsiflexed, and this causes the arch to be maintained

Question 106

abductor hallucis

Answer 106

- muscle runs from the tuberosity of the calcaneus to the base of the proximal phalanx of the big toe - helps sustain the medial longitudinal arch during locomotion

Question 107

hip joint

Answer 107

-deeply cupped acetabulum of the os coxae and the hemispherical head of the femur form a snugly stable ball-and-socket joint

Question 108

lunate surface

Answer 108

- articular surface of the acetabulum - horse shoe shaped - open inferiorly (bc no weight here) - its 2 horns are connected by the transverse acetabular ligament

Question 109

acetabular labrum

Answer 109

- deepens the acetabulum socket | - fibrocartilaginous

Question 110

fovea capitis

Answer 110

- part of the head of the femur that isnt covered by an articular surface - small pit - where blood vessels enter the head

Question 111

ligament of the head of the femur

Answer 111

- ligamentum teres - short ligament that fans out from the fovea capitis to attach to the horns of the lunate surface and the transverse acetabular ligament - helps secure the stability of joint - covered by the synovial membrane - runs through the synovial cavity of the hip joint

Question 112

joint capsule of hip

Answer 112

- attached medially to the acetabular labrum and laterally to the base of the femoral neck - fibrous part of the capsule is very thick over most of its coverage - bc its fibers have different orientations -> there are three separate ligaments 1. iliofemoral 2. ischiofemoral 3. pubofemoral

Question 113

iliofemoral ligament

Answer 113

- arises from the anterior edge of the ilium between the acetabulum and the anterior inferior iliac spine and fans out to insert along a line on the front of the femur between the greater and lesser trochanters called the intertrochanteric line - very strong ligament prevents overextension of the lower limb during standing

Question 114

ischiofemoral ligament

Answer 114

- arises from the back of the acetabulum adjacent to the ischial tuberosity and runs laterally across the back of the femoral neck to attach to the greater trochanter - limits extension of lower limb

Question 115

pubofemoral

Answer 115

- arises from the superior pubic ramus and fans out laterally to insert along the lower part of the intertrochanteric line on the front of the femoral neck - weak ligament limits abduction of the lower limb

Question 116

knee joint

Answer 116

- two articulations: uniaxial hinge between the femur and tibia and gliding plane between the femur and patella - synovial cavity - fibrocartilage discs and ligaments between the femur and tibia are inside the joint capsule

Question 117

meniscus

Answer 117

- C-shaped fibrocartilage disc - overcomes the mismatch between the flat articular surface of the tibia and the rounded condyles of the femur - placed atop each tibial condyle - medial and lateral meniscus - located within the joint capsule

Question 118

fibrous joint capsule of knee

Answer 118

- attaches to the sides and back of the articular surfaces of the femur and tibia - synovial membrane lines fibrous capsule on the sides and back of the joint between the edges of the menisci and the opposing articular surfaces - absent from the front of the joints -> permits the synovial membrane to bulge upward beneath the tendon of the quadriceps femoris muscle

Question 119

suprapatellar bursa

Answer 119

-synovial pouch

Question 120

intracapsular (cruciate) ligaments

Answer 120

- posterior cruciate ligament- runs forward from the back of the intercondylar eminence of the tibia to insert into the inner surface of the medial femoral condyle - anterior cruciate ligament- runs backward from the front of the intercondylar eminence of the tibia to insert into the inner surface of the lateral femoral condyle - cruciate ligaments cross each other in the center of the joint

Question 121

extracapsular (collateral) ligaments

Answer 121

- patellar ligament- runs from the bottom of the patella to the tibial tuberosity -> continuation of the tendon of the quadriceps femoris muscle; separated from the synovial membrane of the joint by a pad of fat - medial (tibial) collateral ligament- runs along the capsule from the medial epicondyle of the femur to the tibia -> attached also to the edge of the medial meniscus - lateral (fibular) collateral ligament- runs across the capsule from the lateral epicondyle of the femur to the head of the fibula

Question 122

ankle joint

Answer 122

- articulation of the talus and the tibia and fibula - permits dorsiflexion and plantar flexion - intertarsal joints are considered apart of the ankle too -> permit eversion, inversion, and rotation - both joints are centered around talus and keystone of movement

Question 123

talocrural (ankle) joint

Answer 123

- involves the articulation of the body of the talus with the tibia and fibula - for dorsiflexion and plantarflexion the superior surface of the talus glides over the distal surface of the tibia - medial and lateral sides of the body of the talus articulate with the medial malleolus and the lateral malleolus -> prevent side to side movement and rotation of the talus - single joint capsule - stabilized by ligaments that prevent the talus from moving anteriorly and posteriorly and from being abducted and adducted - deltoid ligament - lateral collateral ligament

Question 124

deltoid ligament

Answer 124

3 ligaments fan out from the medial malleolus to insert onto the talus and calcaneus

Question 125

lateral collateral ligament

Answer 125

3 ligaments also radiate from the lateral malleolus to insert onto the talus and calcaneus

Question 126

intertarsal joints

Answer 126

- involve articulations between the talus and calcaneus and between them and the navicular and cuboid - two articulations (anterior and posterior) between the talus and calcaneus comprises the -> subtalar joint - articulates between the talus and navicular and between the calcaneus and cuboid constitute the -> transverse tarsal joint - anterior subtalar joint relates the talus to both the calcaneus and the navicular in a single capsule -> part of both the subtalar and the transverse tarsal joint

Question 127

ligaments of the subtalar and transverse tarsal joints

Answer 127

- run on the plantar aspect between the calcaneus and cuboid (laterally) and between the calcaneus and navicular (medially) - latter -> spring ligament

Question 128

ventral rami of spinal nerves

Answer 128

- supply the lower limbs bc they are hypaxial - lower limbs develops as bud from the body wall at level L2-S3 - in order to provide the muscles with nerve fibers from more than one spinal nerve -> the ventral rami are braided together in the lumbosacral plexus

Question 129

lumbosacral plexus

Answer 129

- the ventral rami are braided together in the lumbosacral plexus - separates into dorsal division nerves and ventral division nerves - supply muscles that are developmentally dorsal and those that are developmentally ventral - there is developmental rotation of the lower limb and the separation of the muscles of the thigh and leg into three or four compartments by the deep fascia

Question 130

rotation of the lower limb

Answer 130

- lower limbs develops outward from the body wall such that the thigh projects at a right angle to the body - what eventually becomes the anterior surface of the limb is in the same plane as the back (faces dorsally) - limb eventually begins to bend at the knee, with the knee facing laterally and at the ankle with the top of the foot facing dorsally - next, lower limb rotates 90 degrees at the hip joint such that the dorsal surface of the thigh now comes to face superiorly (towards the head) -> knee still faces laterally - next, the lower limb rotates inward such that the knee now faces anteriorly; relationship of the lower limb to the body is now like that of your leg when you are sitting down - final stage- rotational development simply involves extending the lower limb such that what was originally the dorsal surface of the thigh and leg now faces anteriorly and the dorsal aspect of the foot now faces superiorly - developmental rotation of the lower limb is the reason that in the thigh and leg, developmental dorsal muscles are situated anteriorly, whereas developmentally ventral muscles are situated posteriorly

Question 131

nerve compartments of the lower limb

Answer 131

- 2 nerve compartments in each segments of the lower limb - dorsal division nerve compartment occupies the anterior and lateral aspects of the thigh and leg and the top of the foot - the ventral division nerve compartment occupies the posterior and medial aspects of the thigh and leg, and the sole of the foot

Question 132

muscle compartment of lower limb

Answer 132

- thigh has 4 muscle compartments at the level of the hip joint (upper thigh) and 3 compartments along most of the length of the femur (no lateral) - superior part of the thigh has 4 muscle compartments -> lateral anterior medial and posterior - leg has 3 muscle compartments -> lateral, anterior, posterior (crural compartments) - foot has 2 muscle compartments (one ventral (plantar) and one dorsal)

Question 133

lateral muscle compartment of upper thigh

Answer 133

- contains 4 major abductors of the thigh - innervated by dorsal division - middle and lower portions of thigh lack lateral muscle compartment -> most of thigh only has 3 compartments

Question 134

anterior muscle compartment of upper thigh

Answer 134

- contains the major flexors of the thigh | - innervated by dorsal division nerves

Question 135

medial muscle compartment of upper thigh

Answer 135

- contains the major adductors of thigh - only one is not innervated by ventral division - exception: pectineus muscle which is supplied by dorsal

Question 136

posterior muscle compartment of upper thigh

Answer 136

- contains most of the major extensors | - supplied by ventral division nerves

Question 137

anterior muscle compartment of thigh

Answer 137

- contains the major extensors of leg | - supplied by a dorsal division nerve

Question 138

medial muscle compartment of thigh

Answer 138

- contains major adductors of the thigh and a flexor of the leg - supplied by ventral division

Question 139

posterior muscle compartment of thigh

Answer 139

- contains the major flexors of the leg | - supplied by ventral division nerves

Question 140

lateral crural muscle compartment (leg)

Answer 140

- contains plantarflexors and evertors of the foot | - supplied by a dorsal division nerve

Question 141

anterior crural muscle compartment (leg)

Answer 141

- contains the dorsiflexors of the foot, one of the inverters of the foot, and the extrinsic extensors of the toes - supplied by dorsal division nerves

Question 142

posterior crural muscle compartment (leg)

Answer 142

- contains major plantarflexors of the foot, extrinsic flexors of the toes, and 4 of 5 invertors of the foot - supplied by ventral division nerves

Question 143

dorsal muscle compartment of the foot

Answer 143

- contains the intrinsic short extensors of the toes | - supplied by dorsal division

Question 144

plantar muscle compartment of foot

Answer 144

- contains the intrinsic flexors of the toes | - supplied by ventral division nerves

Question 145

lumbosacral plexus

Answer 145

- lower limbs are served by ventral rami of sevenspinal nerves (L2-S3) via lumbosacral plexus - has 9 roots, but spinal nerves T12 and L1 do not provide fibers to lower limb muscles - lumbar plexus- T12-L4 - sacral plexus- L5-S3 - no trunks or cords (unlike brachial plexus) -> instead ventral and dorsal compartment fibers of each root split off from one another and then combine directly to form peripheral nerves

Question 146

lumbosacral trunk

Answer 146

-connects the lumbar and sacral plexus by a single twig between L4 and L5

Question 147

obturator and femoral nerves: peripheral nerves

Answer 147

- obturator nerve- ventral nerve compartment fibers from L2-L4 - femoral nerve- dorsal nerve compartment fibers from L2-L4 - serve only hip and thigh muscles

Question 148

peripheral nerves

Answer 148

-these 6 nerves serve the hip and thigh muscles and all the muscles below Ventral nerve compartment fibers from L4-S3: -tibial nerve -nerve to obturator internus -nerve to quadratus femoris Dorsal nerve compartment fibers from L4-S3: -common fibular nerve -superior gluteal nerve -inferior gluteal nerve

Question 149

sciatic nerve

Answer 149

- tibial nerve and common fibular nerve run together in a single sheath through much of the thigh - carries both ventral and dorsal fibers

Question 150

Nerves to muscles of the hip that move the thigh: Lateral muscle compartment of the thigh

Answer 150

- run from pelvis to femur - abduct thigh (some medially rotate) - innervated by dorsal nerves - gluteus maximus- inferior gluteal nerve - gluteus medius- superior gluteal nerve - gluteus minimus- superior gluteal nerve - tensor fasciae latae- superior gluteal nerve

Question 151

Nerves to muscles of the hip that move the thigh: Anterior muscle compartment of thigh

Answer 151

- quadriceps femoris are 4 muscles - all flex the thigh (one extends the leg and others flex) - all innervated by dorsal - iliopsoas- femoral nerve - sartorius- femoral nerve - quadriceps femoris- femoral nerve

Question 152

Nerves to muscles of the hip that move the thigh: Medial muscle compartment of the thigh

Answer 152

- 5 muscles run from pelvis to femur and one runs from pelvis to tibia (medial compartment) - all but one adduct the thigh (obturator externus laterally rotates) - gracilis can also flex the knee - all but the pectineus are innervated by the ventral division - adductor longus- obturator nerve - adductor brevis- obturator nerve - adductor magnus (pubofemoral)- obturator nerve - gracilis- obturator nerve - obturator externus- obturator nerve - pectineus- femoral nerve

Question 153

Nerves to muscles of the hip that move the thigh: Posterior muscle compartment of thigh

Answer 153

- all but one extend (quadratus femoris laterally rotates) - all innervated by ventral division of the sciatic nerve - biceps femoris (long head)- tibial nerve - semitendinosus- tibial nerve - semimembranosus- tibial nerve - adductor magnus (ischiocondylar part)- tibial nerve - quadratus femoris- nerve to quadratus femoris

Question 154

Nerves to muscles of the thigh that move the leg: lateral muscle compartment of the thigh

Answer 154

- runs from femur to insert onto fibula - flexes leg - innervated by dorsal division component of the sciatic nerve - bicep femoris (short head)- common fibular nerve

Question 155

Nerves to muscles of the thigh that move the leg: Anterior muscle of compartment of the thigh

Answer 155

- innervated by dorsal nerve - sartorius- femoral nerve - quadriceps femoris- femoral nerve

Question 156

Nerves to muscles of the thigh that move the leg: Medial muscle compartment of the thigh

Answer 156

- adducts lower limb and flexes leg - innervated by ventral division - gracilis- obturator nerve

Question 157

Nerves to muscles of the thigh that move the leg: Posterior muscle compartment of the thigh

Answer 157

- hamstrings - flex leg - innervated by ventral division fibers of sciatic nerve - bicep femoris (long head)- tibial nerve - semitendinosus- tibial nerve - semimembranosus- tibial nerve

Question 158

Nerves to muscles of the leg that move the ankle and toes: Lateral crural muscle compartment

Answer 158

- plantarflexors and most importantly *evert (pronators) the foot - dorsal division nerves - fibularis longus- superficial fibular nerve - fibularis brevis- superficial fibular nerve

Question 159

Nerves to muscles of the leg that move the ankle and toes: Anterior crural muscle compartment

Answer 159

- dorsiflexors of foot - one inverter of foot - extrinsic extensors of toes - dorsal division of nerves - tibialis anterior- deep fibular nerve - extensor hallucis longus- deep fibular nerve - extensor digitorum longus- deep fibular nerve - fibularis tertius- deep fibular nerve

Question 160

Nerves to muscles of the leg that move the ankle and toes: Posterior crural muscle compartment

Answer 160

- plantarflexors of foot - 4 of 5 invertors - extrinsic flexors muscles of toes - popliteus- medial rotator of leg - ventral division nerves - gastrocnemius- tibial nerve - soleus- tibial nerve - tibialis posterior- tibial nerve - plantaris- tibial nerve - popliteus- tibial nerve - flexor hallucis longus- tibial nerve - flexor digitorum longus- tibial nerve

Question 161

Nerves to muscles of the foot that move the toes: Plantar muscle compartment of the foot

Answer 161

- intrinsic flexors of the toes - ventral division nerve - flexor digitorum brevis- medial plantar nerve - flexor hallucis brevis- medial plantar nerve - abductor hallucis- medial plantar nerve

Question 162

Nerves to muscles of the foot that move the toes: Dorsal muscle compartment of the foot

Answer 162

- intrinsic extensors of the toes - dorsal division nerves - extensor digitorum brevis- deep fibular nerve - extensor hallucis brevis- deep fibular nerve

Question 163

dorsal compartment peripheral nerves

Answer 163

- femoral - gluteals - common fibular - deep fibular - superficial fibular

Question 164

dorsal compartment peripheral nerves: femoral

Answer 164

- supplies thigh flexors (like iliopsoas and rectus femoris) and leg extensors (like quadriceps femoris) - descends through the back of the abdomen into pelvis - exits the pelvis under the inguinal ligament into the hollow femoral triangle between sartorius and adductor longus muscles - then branches out

Question 165

dorsal compartment peripheral nerves: gluteals

Answer 165

- superior gluteal and inferior gluteal - supply thigh extensors, abductors, and lateral rotators - descends into the pelvis and exits around the piriformis muscle through the greater sciatic foramen - then branches out to supply the gluteal muscles and the tensor fascia latae

Question 166

dorsal compartment peripheral nerves: common fibular

Answer 166

- supplies only one leg flexor muscle -> short head of biceps femoris - exits the pelvis as part of the sciatic nerve through the greater sciatic foramen - descends the thigh deep to the gluteus maximusand biceps femoris muscles to emerge behind the knee - crosses the lateral aspect of the joint and runs to the top of the fibula -> divides into its 2 principal branches -> deep fibular and superficial fibular

Question 167

dorsal compartment peripheral nerves: deep fibular

Answer 167

- supplies foot dorsiflexors and extrinsic and intrinsic toe extensors - descends the leg across the front of the interosseous membrane and the tibia and then branches onto the dorsum of the foot

Question 168

ventral compartment of peripheral nerves

Answer 168

- obturator | - tibial

Question 169

ventral compartment of peripheral nerves: obturator

Answer 169

- supplies the thigh adductors - descends through the back of the abdomen into the pelvis and exits through the obturator foramen - then branches out

Question 170

ventral compartment of peripheral nerves: tibial

Answer 170

- supplies one thigh adductor (hamstring part of adductor magnus), most of leg flexors and foot plantarflexors, and both extrinsic toe flexors - innervates all but one of the intrinsic toe muscles through its terminal plantar branches - exits the pelvis with the common fibular nerve, as part of the sciatic nerve, through the greater sciatic foramen - descends the thigh as part of the sciatic nerve to emerge into the popliteal fossa behind the knee - crosses the middle of the popliteal fossa and descends along the back of the leg deep to the calf muscles - crosses the medial side of the ankle and then divides into the medial plantar and lateral plantar nerves

Question 171

muscles of the lower limbs

Answer 171

- ventral division- innervated by obturator nerve, nerve to quadratus femoris, nerve to obturator internus, tibial nerve, medial plantar nerve, and lateral plantar nerve - dorsal division- innervated by femoral nerve, superior gluteal nerve, inferior gluteal, inferior gluteal nerve, common fibular nerve, deep fibular nerve, and superficial fibular nerve

Question 172

muscles that move the thigh: Iliopsoas group muscles

Answer 172

- iliopsoas comprises 2 muscles whose fibers join to form a common tendon - PSOAS MAJOR- arises from the vertebral bodies and intervertebral discs from T12 to L5 - its fibers run into the pelvis where they merge with fibers of ILIACUS, which arises from the iliac fossa of the pelvis - the conjoined tendon runs across the superior pubic ramus and below the inguinal ligament - forms the back wall of the femoral triangle - wraps around the femoral neck to insert onto the lesser trochanter - flexes the hip joint - innervated by femoral nerve -> dorsal division

Question 173

muscles that move the thigh: Gluteal group muscles

Answer 173

- there are 4 -> 3 abduct and medially rotate the thigh -> the other extends and laterally rotates the thigh - dorsal compartment - innervated by one of the gluteal nerves - tensor fascia latae - gluteus maximus - gluteus medius - gluteus minimus

Question 174

Gluteal group muscle: tensor fascia latae

Answer 174

- arises from the outer lip of the anterior part of the iliac crest between the anterior superior iliac spine and the iliac tubercle - fibers become tendinous and form part of the iliotibial tract - iliotibial tract inserts onto the lateral condyle of the tibia - flexes, medially rotates, and abducts the thigh - innervated by superior gluteal nerve -> dorsal

Question 175

gluteal group muscle: gluteal maximus

Answer 175

- arises from the posterior part of the iliac crest and the lateral edge of the sacrum and coccyx - inserts onto the gluteal tuberosity on the back of the femur just below and lateral to the lesser trochanter - some of the fibers also insert into the iliotibial tract - fibers of the superior half of the muscle abduct and laterally rotate the thigh - those in its lower half extend and laterally rotate the thigh - recruited as an extensor only when powerful force is required, such as in running and climbing stairs - innervated by inferior gluteal nerve -> dorsal

Question 176

gluteal group muscles: gluteus medius

Answer 176

- arises from the posterior part of the iliac blade and inserts by a tendon onto the lateral aspect of the greater trochanter of the femur - abducts and medially rotates the thigh - innervated by superior gluteal nerve -> dorsal

Question 177

gluteal group muscles: gluteus minimus

Answer 177

- arises from the posterior part of the iliac blade and also inserts by a tendon onto the lateral aspect of the greater trochanter of the femur - lies underneath the gluteus medius - abducts and medially rotates the thigh - innervated by superior gluteal nerve

Question 178

lateral rotator group muscles

Answer 178

- 6 - move the thigh - lateral rotators of the thigh - help maintain the integrity of the hip joint by steadying the femoral head in the acetabulum - all but the piriformis are ventral compartment muscles - obturator internus - gemellus superior - gemellus inferior - quadratus femoris - piriformis - obturator externus

Question 179

lateral rotator group muscles: obturator internus

Answer 179

- arises from the internal margin of the obturator foramen - tendon runs through the lesser sciatic notch and makes a right angle around the ischium to insert on the top of the greater trochanter of the femur - innervated with nerve to obturator internus -> ventral

Question 180

lateral rotator group muscles: gemellus superior

Answer 180

- a small muscle that arises from the ischial spine - its tendon merges with that of obturator internus to insert onto the greater trochanter of the femur - innervated with nerve to obturator internus -> ventral

Question 181

lateral rotator group muscles: gemellus inferior

Answer 181

- is a small muscle that arises from the upper part of the ischial tuberosity - its tendon also merges with that of obturator internus to insert onto the greater trochanter of the femur - innervated by the nerve to quadratus femoris -> ventral

Question 182

lateral rotator group muscles: quadratus femoris

Answer 182

- arises from the lateral edge of the ischial tuberosity and runs laterally to insert onto the intertrochanteric crest on the back of the femur - innervated by the nerve to quadratus femoris -> ventral

Question 183

lateral rotator group muscles: pisiformis

Answer 183

- arises from the lateral aspect of the anterior surface of the sacrum - it runs laterally through the greater sciatic notch to attach to the top of the greater trochanter of the femur - innervated by branches from S1 to S2 -> dorsal compartment

Question 184

lateral rotator group muscles: obturator externus

Answer 184

- attaches to the outer margin of the front of the obturator foramen - runs behind the hip joint to insert into the fossa on the medial side of the greater trochanter - innervated by obturator nerve -> ventral

Question 185

adductor group muscles

Answer 185

- move the thigh - adductors of the thigh - 5 - medial rotate and flex the thigh (most) - 4 of them insert onto the femur and the other inserts on the tibia - all but one are ventral compartment (pectineus) - adductor brevis - adductor longus - adductor magnus - pectineus - gracilis

Question 186

adductor group muscles: adductor brevis

Answer 186

- arises from the external surface of the pubis - inserts onto the upper part of the linea aspera of the femur - also flexes and medially rotates the thigh - innervated by the obturator nerve -> ventral

Question 187

adductor group muscles: adductor longus

Answer 187

- arises from the front of the pubis - inserts onto the distal 2/3rds of the linea aspera of the femur - also flexes and medially rotates the thigh - innervated by obturator nerve -> ventral

Question 188

adductor group muscles: adductor magnus

Answer 188

- one of the largest msucles in the body - 2 parts that are separated inferiorly by a gap - ventral compartment - 2 components are innervated separately: - Adductor (pubofemoral) - Hamstring (ischiocondylar)

Question 189

adductor group muscles: adductor magnus: adductor (pubofemoral)

Answer 189

- component arises from the external surface of the ischiopubic ramus - inserts onto the gluteal tuberosity, the linea aspera, and the medial supracondylar ridge of the femur - also flexes the thigh - innervated by the obturator thigh -> ventral

Question 190

adductor group muscles: adductor magnus: hamstring (ischiocondylar)

Answer 190

- component arises from the ischial tuberosity and runs down the thigh the insert onto the adductor tubercle of the femur - also extends the thigh and is recruited in this role more so than as an adductor - innervated with tibial (sciatic) nerve -> ventral

Question 191

adductor group muscles: pectineus

Answer 191

- arises from the anterior surface of the superior pubic ramus - runs laterally to insert on the back of the femur back the lesser trochanter - also flexes and medially rotates the thigh - innervated by femoral nerve -> dorsal compartment

Question 192

adductor group muscles: gracilis

Answer 192

- arises from the interior part of the pubis - runs straight down the medial surface of the thigh and inserts onto the upper part of the medial surface of the tibia - medially rotates the lower limb and also flexes the knee - innervated by the obturator nerve -> ventral

Question 193

muscles that move the leg

Answer 193

- 10 muscles - arise from the os coxae or femur and insert onto the tibia and fibula - 2 groups: flexors (6) and extensors (4) - leg flexors - leg extensors

Question 194

muscles that move the thigh

Answer 194

- iliopsoas group muscles - gluteal group muscles - lateral rotator group muscles - adductor group muscles

Question 195

muscles that move the leg: leg flexors

Answer 195

- 6 muscles flex the knee - all are potential rotators of the leg - 5 rotate the leg medially - 1 rotates laterally - some flex the hip joint and others extend the thigh - 3 (bicep femoris, semimembranosus, and semitendinosus) -> hamstring muscles - bicep femoris -> long head and short head - semitendinosus - semimembranosus - sartorius - popliteus - gracilis

Question 196

leg flexors: biceps femoris

Answer 196

- has 2 heads that have different origins and innervations -> both laterally rotates the leg - Long head - short head

Question 197

leg flexors: biceps femoris: long head

Answer 197

- arises from the medial part of the ischial tuberosity - runs around the back of the thigh, and its tendon curves posterolateral to the lateral femoral condyle to insert onto the head of the fibula - extends the thigh - innervated by the tibial (sciatic) nerve -> ventral compartment

Question 198

leg flexor: biceps femoris: short head

Answer 198

- arises from the interior two-thirds of the linea aspera and the lateral supracondylar ridge of the femur - merges with the long head tendon just above the knee - innervated by the common fibular (sciatic) nerve -> dorsal

Question 199

leg flexor: semitendinosus

Answer 199

- arises from the ischial tuberosity - runs straight down the back of the thigh and over the back of the medial femoral condyle - its tendon partially merges with that of the gracilis muscle to insert onto the medial side of the proximal part of the tibia - can medially rotate the leg and extend the thigh - innervated by the tibial (sciatic) nerve -> ventral

Question 200

leg flexor: semimembranosus

Answer 200

- arises from the ischial tuberosity - runs deep to semitendinosus and crosses the back of the medial femoral condyle with it - its tendon divides at the back of the knee to insert onto both the medial and the posterior surfaces of the tibia - its other fibers turn upward and laterally into the back of the knee joint capsule - it can also medially rotate the leg and extend the thigh - innervated by the tibial (sciatic) nerve -> ventral

Question 201

leg flexors: sartorius

Answer 201

- arises from just below the anterior superior iliac spine of the os coxae - spirals across the front and medial sides of the thigh - inserts on the medial surface of the upper part of the tibia - can also medially rotate the leg and flex the hip joint - innervates the femoral nerve -> dorsal - crosses over the adductor longus muscle on the front of the thigh -> where they meet they form the apex of an inferiorly pointing -> triangular hollow -> femoral triangle

Question 202

leg flexors: popliteus

Answer 202

- arises from the lateral surface of the lateral femoral condyle by a cordlike tendon - inserts onto the medial aspect of the back of the tibia above the soleal line - medial rotator of the leg - innervated by the tibial nerve -> ventral

Question 203

leg flexors: gracilis

Answer 203

- adductor of the thigh - also flexes and medially rotates the leg - innervated by the obturator nerve -> ventral

Question 204

femoral triangle

Answer 204

- sartorius- lateral border - adductor longus- medial border - inguinal ligament- base - pectineus and iliopsoas muscles- back wall - femoral nerve, femoral artery, and femoral vein run through the triangle anterior to pectineus and iliopsoas - also contains the superficial inguinal lymph nodes

Question 205

leg extensors the Quadriceps femoris

Answer 205

-4 -extend the legs -may also produce flexion at the hip joint -insert onto the patella and via the patellar tendon onto the tibial tuberosity -dorsal compartment -innervated by femoral nerve Quadriceps femoris -rectus femoris -vastus lateralis -vastus medialis -vastus intermedius

Question 206

leg extensors: rectus femoris

Answer 206

- in the middle of the 3 superficial components - arises from the anterior inferior iliac spine and from just above the acetabulum - fibers run down the middle of the thigh to insert onto the proximal margin of the patella - crosses over the hip joint - flexes the thigh

Question 207

leg extensors: vastus lateralis

Answer 207

- lateral of the superficial components - arises from the front and side of the greater trochanter and from the femoral shaft along the lateral margin of the linea aspera - inserts onto the patella - some fibers run onto the front of the lateral condyle of the tibia

Question 208

leg extensors: vastus medialis

Answer 208

- medial of the superficial parts - arises from the intertrochanteric line and the femoral shaft along the medial margin of the lina aspera - inserts onto the patella - some fibers run onto the front of the medial condyle of the tibia

Question 209

leg extensors: vastus intermedius

Answer 209

- deep component - arises from the upper three-fourths of the femoral shaft - inserts onto the patella behind the tendons of the superficial vasti, although they intermingle - small bundle of fibers runs deep to the main tendon to insert onto the upper part of the articular capsule of the knee - fibers constitute the articularis genu muscles - serves to draw the capsule proximally during extension of the knee - prevents it from being caught between the patella and femur

Question 210

muscles that move the foot

Answer 210

- 12] - cross the ankle joint to insert onto bones of the foot - 8 insert onto tarsal bones or metatarsals -> their action are restricted to movement at the ankle joint - plantar, dorsiflex, invert, and/or evert foot - 4 muscles cross the ankle joint and insert onto the phalanges - extrinsic muscles of the toes, and they act to extend or flex the toes - plantarflexors- 6 - dorsiflexors- 2 - plantarflexors of the foot - dorsiflexors of the foot

Question 211

muscles that move the foot: plantarflexors of the foot

Answer 211

- 6 - 3 are strictly plantar flexors - 3 plantar flex and also invert and evert - gastrocnemius - soleus - plantaris - tibialis posterior - fibularis (=peroneus) longus - fibularis (=peroneus) brevis

Question 212

plantarflexors of the foot: gastrocnemius

Answer 212

- most superficial of the calf muscles - has 2 heads that arise from the medial and lateral epicondyles of the femur - their fibers merge to form a common tendon that becomes prominent at about midclaf - this is the achilles tendon (= calcaneal tendon) - largest tendon in the body - inserts onto the tuberosity at the back of the calcaneus - gastrocnemius acts to plantarflex the foot - flex the legs - innervates the tibial nerve -> ventral compartment

Question 213

plantarflexors of the foot: soleus

Answer 213

- lies deep to gastrocnemius - arises from the back of the head of the fibula and the soleal line of the tibia - its fibers merge with the achilles tendon at about midcalf - also inserts onto the calcaneal tuberosity - acts only to plantarflex - innervates the tibial nerve -> ventral compartment

Question 214

plantarflexors of the foot: plantaris

Answer 214

- arises from the posterior surface of the femur above the lateral condyle - runs medially across the back of the knee, and its long, thin tendon runs down the back of the tibia to insert onto the calcaneal tuberosity medial to the achilles tendon - only plantarflex - innervates tibial nerve -> ventral

Question 215

plantarflexors of the foot: tibialis posterior

Answer 215

- arises from the lateral half of the upper part of the back of the tibia and from the medial side of the upper part of the fibula - thin tendon curves around the back of the medial malleolus of the tibia and into the sole of the foot - inserts principally onto the underside of the navicular bone, but its tendon fans out to insert onto the other tarsals bones (except the talus) and onto the base of the middle three metatarsals (2, 3, and 4) - inverts the foot - innervates tibial nerve -> ventral compartment

Question 216

plantarflexors of the foot: fibularis (=peroneus) longus

Answer 216

- arises from the lateral surface of the proximal two-thirds of the fibula - its thin tendon wraps around the back of the lateral malleolus of the fibula - it then turns underneath the calcaneus and crosses the sole of the foot to insert onto the base of the first metatarsal and the adjacent medial cuneiform bone - also everts the foot - innervates the superficial fibular nerve -> dorsal

Question 217

plantarflexors of the foot: fibularis (=peroneus) brevis

Answer 217

- arises from the distal two-thirds of the fibula - its thin tendon wraps around the lateral malleolus anterior to the tendon of peroneus longus - then runs straight forward to insert onto the base of the fifth metatarsals - also everts the foot - innervates the superficial fibular nerve -> dorsal compartment

Question 218

dorsiflexors of the foot

Answer 218

- 2 - either invert or evert - dorsal compartment - tibialis anterior - fibularis (=peroneus) tertius

Question 219

dorsiflexors of the foot: tibialis anterior

Answer 219

- arises from the lateral side of the proximal half of the tibial shaft - angles medially across the front of the tibia and top of the foot to insert onto the base of the first metatarsal - also a powerful invertor of the foot - innervated by the deep fibular nerve -> dorsal

Question 220

dorsiflexors of the foot: fibularis (=peroneus) tertius

Answer 220

- arises from the anterior margin of the inferior quarter of the fibula and inserts onto the bae of the 5th metatarsals - its tendon runs immediately lateral to that of extensor digitorum longus and it arises immediately below that muscle - fibularis tertius is often regarded as simply a part of the larger extensor digitorum - everts the foot - innervated by the deep fibular nerve -> dorsal

Question 221

muscles that move the toes

Answer 221

- 15 - can move 1 or more of the toes - two groups: - 4 extrinsic muscles arise from bones of the leg - 11 intrinsic muscles take origin from within the foot itself - hallucis- insert onto the big toe (hallux) - digitorum or digiti- muscles that move lateral toes - extrinsic flexors of the toes - extrinsic extensors of the toes - intrinsic muscles of the toes

Question 222

extrinsic flexors of the toes

Answer 222

- there are 2 extrinsic toe flexors - both can invert the foot at the ankle joint - ventral compartment - innervated by the tibial nerve - flexor digitorum longus - flexor hallucis longus

Question 223

muscles that move the toes: flexor digitorum longus

Answer 223

- arises from the medial part of the back of the tibial shaft and by an aponeurosis from the fibula - its thin tendon turns under the medial malleolus and then runs forward, dividing into 4 bands - each band inserts onto the distal phalanx of 1 of the 4 lateral toes - supplied by the tibial nerve -> ventral

Question 224

muscles that move the toes: flexor hallucis longus

Answer 224

- arises from the lower two-thirds of the back of the fibula and the fascia over the back of tibialis posterior - its thin tendon turns under the medial malleolus and talus - its crosses the inferior surface of the calcaneus - inserts onto the distal phalanx of the big toe - propels the body upward and forward at toe off - supplied by the tibial nerve -> ventral

Question 225

extrinsic extensors of the toes

Answer 225

- 2 extrinsic toe extensor - 1 can invert the foot, and the other can also evert the foot at the ankle joint - dorsal compartment - supplied by the deep fibular nerve - extensor digitorum longus - extensor hallucis longus

Question 226

extrinsic extensors of the toes: extensor digitorum longus

Answer 226

- arises form the lateral condyle of the tibia and the proximal three-fourths of the fibula - its tendon crosses the ankle anterior to the tibia and then splits into 4 bands - insert onto the middle and distal phalanges of the lateral 4 toes - everts the foot - supplied by the deep fibular nerve -> dorsal

Question 227

extrinsic extensors of the toes: extensor hallucis longus

Answer 227

- arises from the middle of the anterior edge of the fibula - its tendon crosses the ankle anterior to the tibia - inserts onto the distal phalanx of the big toe - inverts the foot - supplied by the deep fibular nerve -> dorsal

Question 228

intrinsic muscles of the toes

Answer 228

- 11 - all but one (or two) are located within the sole of the foot - some maintain its longitudinal arch during locomotion - extensor digitorum brevis - flexor digitorum brevis - abductor hallucis - flexor hallucis brevis

Question 229

intrinsic muscles of the toes: extensor digitorum brevis

Answer 229

- the only dorsal compartment in the foot - arises from the superior surface of the calcaneus and separates into 4 bellies - the medial belly is the largest -> extensor hallucis brevis -> inserts onto the proximal phalanx of the big toe - other three bellies -> extensor digitorum brevis -> insert onto the proximal phalanges of the 2nd, 3rd, and 4th toes - extends the medial 4 toes - supplied by the deep fibular nerve -> dorsal

Question 230

intrinsic muscles of the toes: flexor digitorum brevis

Answer 230

- the most superficial intrinsic muscle in the sole of the foot - arises from the calcaneal tuberosity and divides into 4 tendons - insert onto the middle phalanges of the 4 lateral toes - flexes these toes - supplied by the medial plantar nerve -> ventral

Question 231

intrinsic muscles of the toes: abductor hallucis

Answer 231

- is the most superficial muscle on the medial aspect of the sole of the foot - arises from the calcaneal tuberosity - inserts onto the base of the proximal phalanx of the big toe - can abduct and slightly flex the big toe - helps sustain the medial side of the longitudinal arch of the foot during locomotion - supplied by the medial plantar nerve -> ventral

Question 232

intrinsic muscles of the toes: flexor hallucis brevis

Answer 232

- arises by 2 heads from the plantar surfaces of the distal tarsal bones - inserts onto the base of the proximal phalanx of the hallux by way of the 2 sesamoid bones that lie on the ventral side of its metacarpophalangeal (MP) joint - flexes the hallux - important in toe off during walking and running - supplied by the medial plantar nerves -> ventral

Question 233

aorta

Answer 233

- supplies the lower limb at its terminal bifurcation in front of L4 - divides to form a common iliac artery on the left and right sides - within the pelvis, the common iliac divides into the internal iliac artery and external iliac artery - external iliac artery- principle blood supply to lower limbs; exits the pelvis next to the iliopsoas muscle between the inguinal ligament and the superior pubic ramus - some blood to the lower limb derives from the internal iliac artery via the obturator artery and from the superior and inferior gluteal arteries - once external iliac artery passes below the inguinal ligament into the femoral triangle -> changes to femoral artery

Question 234

femoral artery

Answer 234

- gives off the largest branch the profunda (deep) femoris artery - descends along the posteromedial aspect of the thigh -> supplies the thigh adductor and hamstring muscles - continues down the posteromedial side of the thigh in a canal through the adductor muscles - canal -> subsartorial canal - pierces adductor magnus and becomes -> popliteal artery

Question 235

popliteal artery

Answer 235

- crosses the back of the knee -> gives off several major genicular branches that anastomose around the joint - divides into the anterior tibial artery and posterior tibial artery just below the back of the knee

Question 236

anterior tibial artery

Answer 236

- passes anteriorly between the tibia and fibula and runs inferiorly along the interosseous membrane - when it crosses the ankle -> becomes the dorsalis pedis artery

Question 237

posterior tibial artery

Answer 237

- gives off a branch -> the fibular artery - fibular artery runs along the back of the fibula to the heel - posterior tibial artery continues down the back of the leg, deep to soleus - after crossing the ankle medial to the calcaneus, it divides into the medial and lateral plantar arteries

Question 238

deep veins

Answer 238

- venae comitantes- 1 or 2 veins that run alongside arteries - fibular veins joins the posterior tibial vein - posterior tibial vein then joins anterior tibial vein to form the popliteal vein - popliteal vein runs proximal across the back of the knee -> becomes the femoral vein - femoral vein continues proximally below the inguinal ligament to become the external iliac vein -> joined by the internal iliac vein -> forms the common iliac vein - left and right common iliac veins to join to form the inferior vena cava at the level of the intervertebral disc between L5 and S1

Question 239

superficial veins

Answer 239

- form a network in the superficial fascia - not related to any arteries - great saphenous vein- lower limbs version of the cephalic vein - drains the dorsum of the foot, running anterior to the medial malleolus of the tibia and superiorly along the posteromedial surface of the calf - crosses the knee about 4 finger-breadth medial to the patella - continues proximally along the medial side of the thigh to join the femoral vein within the femoral triangle