hind Limb O, I, & A

Question 1

Hamstring muscles what are these muscles?

what action to the do?

Answer 1

Group of three muscles (biceps femoris, semitendinosus, semimembranosus) that all arise, in part or whole, from the ischiatic tuberosity; all are
extensors of the hip and all can flex the stifle; dependent upon limb position, may also extend the stifle

Question 2

biceps femoris

Answer 2

O: sacrotuberous ligament & ischiatic tuberosity

I: patella, patellar lig., & cranial border of tibia via fascia lata and crural fascia; the tentuber calcanei via common calcanean tendon

A: extend hip, stifle, & hock; can flex stifle when not bearing weight

Note: The tendon of this muscle contributes to the common calcanean tendon.

Question 3

semitendinosus

Answer 3

O: ischiatic tuberosity

I: medial surface of tibial body; tuber calcanei via common calcanean tendon

A: extend hip; flex stifle; extend hock

Note: The tendon of this muscle contributes to the common calcanean tendon

Question 4

semimembranosus

Answer 4

O: isciatic tuberosity

I: distal and medial aspect of the caudal femur and
medial condyle of the tibia

A: extend hip; extend or flex stifle depending on limb position

Note: this m has 2 bellies of = size.

Question 5

sartorius

Answer 5

O: crest of ilium & thoracolumbar fascia; ventral border of ilium

I: patella and cranial border of tibia

A: flex hip; extend stifle (weight bearing); flex stifle (not weight bearing)

NOTE: Has cranial and caudal parts. Caudal part forms the cranial border of the femoral triangle

Question 6

gracilis

Answer 6

O: pelvic symphysis via symphysial tendon

I: cranial border of tibia; tuber calcanei via common calcanean tendon

A: adduct limb; flex stifle; extend hip and hock

Note: The tendon of this muscle contributes to the common calcanean tendon.

Question 7

pectineus

Answer 7

O: pubis (pre-pubic tendon and iliopubic eminence)

I: distal end of caudomedial aspect of femur (medial
lip of caudal rough surface)

A: adduct limb

NOTE: Forms the caudal border of the femoral triangle

Question 8

adductor (magnus et

brevis and longus)

Answer 8

O: pelvic symphysis via symphysial tendon;
ventral surface of pubis and ischium

I: caudolateral aspect of femur (entire lateral lip of
caudal rough surface of femur)

A: adduct limb; extend hip

Question 9

tensor fasciae latae

Answer 9

O: tuber coxae; aponeurosis of middle gluteal m.

I:lateral femoral fascia, a.k.a. fascia lata

A: tense fascia lata; flex hip; extend stifle

NOTE: Has cranial and caudal parts. Note that the cranial part is continuous with the superficial layer of the fascia lata and the caudal part is continuous with the deep layer of the fascia lata.

Question 10

superficial gluteal

Answer 10

O: sacrotuberous ligament; deep gluteal fascia

I:third trochanter of the femur

A: extend hip; abduct limb

Question 11

middle gluteal

Answer 11

O: crest and gluteal surface of ilium

I:greater trochanter of the femur

A: extend hip; abduct hip; rotate pelvic limb medially

NOTE: There is a piriformis muscle that is considered part of the middle gluteal.

Question 12

deep gluteal

Answer 12

O: body of ilium; ischiatic spine

I:greater trochanter of the femur

A: extend hip; abduct hip; rotate pelvic limb medially

Question 13

articularis coxae

Answer 13

lies directly over the ventral aspect of the coxofemoral joint capsule

Question 14

internal obturator

Answer 14

O: dorsal surface of ischium and pubis; dorsal pelvic
symphysis

I:trochanteric fossa of the femur

A: rotate pelvic limb laterally

NOTE: its tendon and subtendinous bursa as the tendon passes over the lesser ischiatic notch.
- This is one of the four small pelvic association muscles.
- Origin is within the bony pelvic canal and the muscle extends over the dorsal surface of the
obturator foramen.

Question 15

gemelli

Answer 15

O:lateral surface of ischium, ventral to the lesser ischiatic notch

I:trochanteric fossa of the femur

A: rotate pelvic limb laterally

Question 16

quadratus femoris

Answer 16

O: ventral surface of caudal ischium

I:intertrochanteric crest of the femur

A: rotate pelvic limb laterally; extend hip

Note: This is one of the four small pelvic association muscles

Question 17

external obturator

Answer 17

O: ventral surface of pubis and ischium

I: trochanteric fossa of the femur

A: rotate pelvic limb laterally

Note: This is one of the four small pelvic association muscles

Question 18

quadriceps femoris

Answer 18

O: ilium (rectus femoris); proximal aspect of femur

I: tibial tuberosity via the patellar ligament

A: flex hip (rectus femoris); extend stifle (all heads)

Note: This muscle has four heads: rectus femoris, vastus lateralis, vastus intermedius, and vastus medialis. Of the four heads, the rectus femoris is the only one that spans both the hip and stifle joints. This muscle group is the main extensor of the stifle and is therefore essential for weight bearing.

Question 19

iliopsoas

Answer 19

O: ventral aspect of lumbar vertebrae; cranioventral
ilium

I: lesser trochanter of the femur

A: flex hip

Note: This muscle is formed by two muscles: psoas major and iliacus, both of which originate deep to the abdominal wall. however, you can see the iliopsoas complex extending through the muscular lacuna of the
abdominal wall adjacent to the vasuclar lacuna.

Question 20

cranial tibial

Answer 20

O: proximal and lateral aspect of the tibia near the extensor groove

I: proximal plantar surface of metatarsals I and II

A: flex tarsus; rotate paw laterally so plantar surface faces medially

Note: The tendon of this muscle is held down by the crural extensor retinaculum, along with the tendon of the long digital extensor m.

Question 21

long ditital extensor

Answer 21

O: extensor fossa of the femur

I: extensor processes of distal phalanges digits II, III, IV, and V.

A: extend digits; flex tarsus

Note: The tendon of this muscle is held down by the crural extensor retinaculum, along with the tendon of the
cranial tibial m. Additionally, the tarsal extensor retinaculum holds the tendon of this muscle in place on the dorsal surface of the metatarsus.

Question 22

fibularis longus or peroneus

longus

Answer 22

O: lateral collateral ligament; proximal aspect of tibia and fibula

I:tarsal bone IV; plantar aspect of proximal ends of
metatarsals

A: flex tarsus; rotate paw medially so plantar surface faces laterally

Question 23

gastrocnemius

Answer 23

O: medial and lateral supracondylar tuberosities of the femur

I: tuber calcanei

A: extend tarsus; flex stifle

Note: This muscle has two heads: medial head and lateral heads. Each of these heads contains a sesamoid bone (fabellae) in their tendons of origin. The two muscular heads basically envelop the muscular portion of the superficial digital flexor
- The tendon of the
gastrocnemius m., along with the tendon of the SDF, forms the main central component of the common calcanean tendon.

Question 24

superficial digital flexor

Answer 24

O: lateral supracondylar tuberosity of the femur (in common with lateral head of the gastrocnemius m.)

I: tuber calcanei; plantar aspect of the base of the middle phalanx of digits II, III, IV, and V

A: flex stifle; extend tarsus; flex digits

Note: The tendon of the SDF, along with the tendon of the gastrocnemius m., forms the main central component of the common calcanean tendon.
- gastrocnemius. The tendon of the SDF “caps
the hock” and has attachments to the medial and lateral aspects of the calcaneus. There is an ntertendinous calcanean bursa between the tendons of the SDF and the gastrocnemius.
Additionally, there is a subcutaneous calcanean
bursa between the skin and the tendon of the SDF.

Question 25

deep digital flexor

Answer 25

O: proximal tibia and fibula and adjacent interosseus membrane

I: between the two. plantar aspect of the base of the distal phalanx of digits I - V

A: flex digits; extend tarsus

Note: This muscle has two heads: lateral digital flexor (or lateral head of the DDF) and medial digital flexor (or medial head of the DDF).
- the tendon (lateral head)
passing over the sustentaculum tali of the calcaneus where it is held down by the flexor retinculum.

Question 26

popliteus

Answer 26

O: lateral condyle of femur

I:proximal and caudal aspect of the tibia

A: flex stifle; rotate leg (crus) medially

Note: - This muscle has a popliteal sesamoid bone in its tendon of origin

Question 27

fibularis brevis.

Answer 27

O: idk

I: idk

A: idk

Question 28

what muscle is the main flexor of the hip?

Answer 28

Iliosoas

Question 29

iliosoas

Answer 29

iliacus m + psous major
O: cranioventral ilium + lumbar vertebrae
I: lesser tubercle of the femur
A: flex the hip