Lecture 5: Anatomy of Thigh and Stifle

Question 1

what is the portion of the pelvic limb between the pelvic girdle and stifle

Answer 1

thigh

Question 2

how is movement of the thigh achieved

Answer 2

muscles that move the coxofemoral joint

Question 3

3 components/joints of the stifle

Answer 3

femoro-tibial
femoro-patellar
proximal tibio-fibular

Question 4

what connects all 3 joints of the stifle

Answer 4

single capsule

Question 5

what kind of bone is the patella

Answer 5

sesamoid bone

Question 6

sesamoid bone definition

Answer 6

floating bone that grows within a tendon

Question 7

location of patella

Answer 7

within tendon of quadriceps femoris

Question 8

extra sesamoid bone in canine stifle

Answer 8

femoro-fabellar joint

Question 9

fabellae

Answer 9

sesamoid bone in proximal heads of gastrocnemius

Question 10

what kind of synovial joint is the stifle

Answer 10

complex = joint capsule + articular cartilage + discs/menisci

Question 11

function of menisci

Answer 11

stabilize movement of round femoral condyles on flat tibial condyles = stabilize movement for femorotibial articulation

Question 12

2 menisci in stifle

Answer 12

lateral
medial

Question 13

stifle menisci: characteristics (2)

Answer 13

fibrocartilage discs
semilunar shape

Question 14

6 ligaments that support the stifle

Answer 14

patellar
medial collateral
lateral collateral
caudal cruciate
cranial cruciate
meniscofemoral

Question 15

patellar ligament/tendon

Answer 15

connect patella to tibia

Question 16

medial collateral ligament

Answer 16

connect femur to tibia

Question 17

lateral collateral ligament

Answer 17

connect femur to fibula

Question 18

caudal cruciate ligament function

Answer 18

prevent CAUDAL slip of tibia

Question 19

cranial cruciate ligament function

Answer 19

prevent CRANIAL slip of tibia

Question 20

what do caudal and cranial cruciate ligaments do relative to each other

Answer 20

criss cross

Question 21

meniscofemoral ligament

Answer 21

connect menisci to femur –> stabilize menisci

Question 22

2 main movements at stifle

Answer 22

flexion
extension

Question 23

in cats, the stifle has greater capacity for what 2 movements

Answer 23

translational mobility
rotation along long axis of tibia

Question 24

what happens as stifle is flexed

Answer 24

lateral collateral ligament loosens –> allows internal rotation of tibia on femur –> cruciate ligaments twist on each other to limit this internal rotation

Question 25

what happens as stifle is extended

Answer 25

lateral collateral ligaments tighten --> tibia rotates externally --> cruciate ligaments untwist (no limit on external rotation)

Question 26

which cruciate ligament is more commonly torn

Answer 26

cranial

Question 27

cause of CCL tear

Answer 27

sudden rotation of flexed stifle (slipping)

Question 28

is a CCL tear more commonly acute or chronic

Answer 28

chronic

Question 29

chronic cause of CCL tear

Answer 29

degenerative changes in ligaments

Question 30

medial compartment of the stifle: 4 muscles, nerve, artery, action

Answer 30

sartorius, gracilis, adductor, pectineus obturator artery femoral nerve, obturator nerve flex stifle

Question 31

lateral compartment of the stifle: 3 muscles, innervation, action

Answer 31

biceps femoris, semitendinosus, semimembranosus deep femoral artery sciatic nerve flex or extend stifle

Question 32

cranial compartment of the stifle: 5 muscles, innervation, artery, action

Answer 32

quadriceps femoris = vastus medialis, vastus lateralis, vastus intermedius, rectus femoris iliopsoas femoral artery femoral nerve extend stifle

Question 33

4 muscles of quadriceps femoris

Answer 33

rectus femoris vastus medialis vastus lateralis vastus intermedius

Question 34

muscle action of quadriceps femoris

Answer 34

extend stifle

Question 35

muscle action of iliopsoas

Answer 35

flex hip

Question 36

cranial part of sartorius action (stifle)

Answer 36

extend stifle

Question 37

caudal part of sartorius action (Stifle)

Answer 37

flex stifle

Question 38

gracilis action (stifle)

Answer 38

flex

Question 39

semitendinosus action (stifle)

Answer 39

flex

Question 40

what is the extensor group at the stifle

Answer 40

quadriceps femoris

Question 41

origin of rectus femoris

Answer 41

ileum

Question 42

quadriceps femoris: insertion, innervation

Answer 42

tibial tuberosity via patellar ligament femoral nerve

Question 43

specializations of horse stifle enable

Answer 43

horse can lock stifle when hindlimb is extended (save energy)

Question 44

specialization of equine distal femur

Answer 44

enlarged medial epicondylar ridge

Question 45

2 surfaces on equine trochlea

Answer 45

gliding resting

Question 46

what shape is equine patella

Answer 46

diamond

Question 47

2 surfaces of equine patella

Answer 47

caudally facing surface distally directed surface

Question 48

caudally facing surface of equine patella engages

Answer 48

gliding surface of trochlea

Question 49

distally directed surface of equine patella engages

Answer 49

resting surface of trochlea when in full extension

Question 50

number of patellar ligaments: dog vs horse

Answer 50

dog = 2 horse = 3

Question 51

3 patellar ligaments of horse

Answer 51

intermediate patellar lateral patellar medial patellar

Question 52

3 other ligaments of equine stifle

Answer 52

medial femoropatellar medial collateral medial meniscus

Question 53

what 3/6 STIFLE muscles are innervated by femoral nerve

Answer 53

iliopsoas sartorius quadriceps femoris = vastus medialis, vastus lateralis, vastus intermedius, rectus femoris

Question 54

2 cutaneous branches off femoral nerve

Answer 54

caudal lateral

Question 55

function of saphenous nerve

Answer 55

sensory to medial leg and tarsus

Question 56

effect of dysfunction of femoral nerve

Answer 56

paralyze quadriceps stifle collapses = entire limb disabled no compensation no sensation on skin of medial surface of limb

Question 57

locking mechanism of stifle

Answer 57

caudal facing surface of patella engages with gliding surface of trochlea (femur) during resting position: medial patellar ligament runs even with edge of corresponding ridge of trochlea --> position maintained without assistance of quadriceps femoris --> this position is unstable so patella is easily dislodged BUT it slips back onto the gliding surface of the trochlea

Question 58

origin of femoral nerve

Answer 58

L4-L6

Question 59

where does femoral nerve enter thigh (between what 2 muscles)

Answer 59

sartorius and pectineus = femoral nerve