Large Animal Anatomy: Pelvis And Pelvic Limb

Front 1

Where is the right kidney located in the horse?

Back 1

Ventral to last 2-3 ribs
Can't be palpated

Front 2

Where is the left kidney located in the horse?

Back 2

Ventral to the 18th rib and transverse processes of the first few lumbar vertebrae

Front 3

Hunter's Bump

Back 3

Subluxation of the sacroiliac joint, visible as excess prominence or asymmetry of the sacral tubers

Front 4

What forms the pelvic cavity boundaries in the horse?

Back 4

Dorsal: by sacrum and first 2-3 caudal vertebrae (roof of pelvic cavity is slightly concave in length)

Ventral: by fused pubis symphysis and ischium table (ventral os coxae)

Lateral: by ilium, sacrosciatic ligament, ischial spine, and ischial tuber

Front 5

What are the four ways to measure (imaginary lines) the equine bony pelvis?

Back 5

1. Axis of pelvic canal: line drawn through centers of pelvic inlet, pelvic cavity, and pelvic outlet; the more horizontal this axis is, the easier parturition is for the mare

2. Conjugata: line drawn from sacral promontory to pecten of pubis; vertical measurement of pelvic inlet

3. Diagonal conjugata: vertical line drawn from pecten of pubis to roof of pelvic cavity; diameter of pelvic cavity

4. Slope of pelvis: line drawn from coxal tuber to ischial tuber (can visualize this externally, via palpation of tubers)

Front 6

What are the four pouches found within the equine pelvic cavity formed by reflections of peritoneum?

Back 6

1. Rectogenital pouch: located between rectum dorsally and uterus (or deferent ducts in genital fold) ventrally

2. Pararectal fossa: portions of rectogenital pouch extending on either side of rectum; bounded ventrally by vagina (or genital fold) and laterally by broad ligaments

3. Vesicogenital pouch: located between uterus dorsally, bladder ventrally, and lateral ligaments of bladder laterally

4. Pubovesical pouch: bounded by bladder dorsally, pubis ventrally, and median ligament of bladder medially

Front 7

Where is the deep inguinal ring located and what are its boundaries in the horse?

Back 7

Located along free caudal edge of internal abdominal oblique m.

Bounded caudally by inguinal ligament and cranially by caudal border of internal abdominal oblique m.

Bounded laterally by origin of internal abdominal oblique m. from external abdominal oblique m.

Bounded medially by the lateral edge of the prepubic tendon

Front 8

What structures pass through the inguinal canal in the male horse?

Back 8

Spermatic cord, external pudendal a., genitofemoral n., and lymphatic vessels

Front 9

What structures pass through the inguinal canal in the female horse?

Back 9

Genitofemoral n., external pudendal a., lymphatic vessels

Front 10

What is the site of communication between vaginal tunic and peritoneal cavity?

Back 10

Vaginal ring

Front 11

What are the boundaries of the femoral triangle?

Back 11

Bordered cranially by sartorius m., medially by external abdominal oblique m., and laterally by quadriceps femoris m.

Front 12

Where are the ovaries located in the horse?

Back 12

Located in dorsal part of abdominal cavity, cranioventral to iliac wings and just lateral to median plane
At level of L5, midway between last rib and tuber coxae (palpable rectally)
Right ovary: located medial to base of cecum
Left ovary: located dorsal to mass of descending colon

Front 13

What are the ovaries suspended by?

Back 13

Mesovarium

Front 14

What is the cranial free border of mesovarium that extends from ovary to body wall?

Back 14

Suspensory ligament of ovary

Front 15

Where is the proper ligament of ovary located?

Back 15

Extends from uterine end of ovary to cranial part of uterine horn; lies medial to ovarian bursa

Front 16

Where is the sole site of ovulation of mature follicles in the horse?

Back 16

Ovulation fossa

Front 17

What are the uterine tubes suspended by?

Back 17

Mesosalpinx

Front 18

What are the three regions of the uterine tube?

Back 18

1. Infundibulum
2. Ampulla
3. Isthmus

Front 19

Where is the round ligament of the uterus located in the horse?

Back 19

Extends from the lateral surface of the uterus to the region of the deep inguinal ring

Front 20

What is the principle blood supply to the equine uterus?

Back 20

External iliac a. to the uterine a.

Front 21

What artery in the horse supplies the vagina, cervix, caudal uterine body, bladder, and urethra?

Back 21

Internal pudendal a. to the vaginal a.

Front 22

What artery in the horse supplies the cranial uterine horns?

Back 22

Uterine branch of the ovarian a.

Front 23

What is the term for the depression in the vagina on either side of the portico vaginalis?

Back 23

Fornix of the vagina

Front 24

What arteries supply the equine vagina?

Back 24

Cranial: vaginal a.
Caudal: vestibular branch of the internal pudendal a.

Front 25

What is the common termination of the urinary and reproductive tracts?

Back 25

Vestibule

Front 26

What structure is homologous to the corpus cavernosum penis?

Back 26

Clitoris

Front 27

Where is the clitoris located?

Back 27

In the ventral commissure of the vulva

Front 28

What structure is homologous to the glans penis?

Back 28

Glans clitoris

Front 29

Where is the glans clitoris located?

Back 29

Within the clitoral fossa

Front 30

What structure is homologous to the corpus spongiosum?

Back 30

Vestibular bulb

Front 31

What artery supplies the vestibular bulb?

Back 31

Internal pudendal a. to the a. of the vestibular bulb

Front 32

What three structures make up the broad ligament in the female?

Back 32

1. Mesometrium
2. Mesovarium
3. Mesosalpinx

Front 33

Explain the duct system of the equine udder.

Back 33

Each half contains 1 teat with 2 orifices.
Each half has 2-3 separate lactiferous duct systems that drain into a common lactiferous sinus.
Canals and duct systems remain separate within the same half.

Front 34

What is the lactiferous sinus?

Back 34

Teat sinus plus gland sinus

Front 35

What is the gland sinus?

Back 35

Proximal sinus contained within the gland

Front 36

What is the teat sinus?

Back 36

Distal sinus contained within the teat, communicates with the teat orifice via the teat canal

Front 37

How many duct systems does each teat have in the dog, horse, and ruminant?

Back 37

Dog: multiple ducts per teat
Ruminants: one duct per teat
Equine: two ducts per teat

Front 38

What is the blood supply to the equine udder?

Back 38

External iliac a. to pudendoepigastric a. to external pudendal a. to mammary aa.

3 branches to mammary aa.:
1. Caudal superficial epigastric a. to cranial mammary vessels
2. Ventral labial a. to caudal mammary vessels
3. Branch directly to udder

Front 39

What is the male homologue to the broad ligament?

Back 39

Genital fold

Front 40

What is contained in the spermatic cord?

Back 40

Ductus deferens
Mesoductus deferens
Deferentail a. and v.
Testicular a./v./n.
Mesorchium

Front 41

What is the cremaster m.?

Back 41

Slip of internal abdominal oblique m. that is closely adhered to the caudolateral surface of the parietal vaginal tunic that acts to elevate the testes

Front 42

What is the tough fibromuscular layer closely adhered to scrotal skin that extends to form the median scrotal septum between the right/left testes?

Back 42

Tunica dartos

Front 43

What transports sperm from the efferent ductules to the ductus deferens?

Back 43

Epididymis

Front 44

What is the connection of visceral vaginal tunic between tail of epididymis and the caudal end of testis?

Back 44

Proper ligament of the testis

Front 45

What is the thick serous fold/connection between the tail of the epididymis and the parietal vaginal tunic?

Back 45

Ligament of the tail of the epididymis

Front 46

Where does the ductus deferens open into the urethra?

Back 46

Opens into the urethra via ejaculatory duct (common duct with vesicular gland) alongside seminal colliculus

Front 47

What is the enlargement of the terminal ductus deferens?

Back 47

Ampulla

Front 48

What are the accessory sex glands that are smooth-surfaced, pear-shaped glands with large central lumens?

Back 48

Vesicular glands (seminal vesicles)

Front 49

What is the accessory sex gland in the horse that is composed of 2 lateral lobes joined by narrow isthmus dorsal to urethra?

Back 49

Prostate

Front 50

What are the accessory sex glands in the horse that are paired glands located at pelvic outlet, dorsolateral to urethra as it turns at ischial arch?

Back 50

Bulbourethral glands

Front 51

What accessory sex glands does the horse have?

Back 51

Ampulla
Prostate
Vesicular glands
Bulbourethral glands

Front 52

What is the ventral depression along cranial surface of glans penis in the horse that surrounds the urethral process?

Back 52

Fossa glandis

Front 53

What is the urethral sinus?

Back 53

Caudal part of fossa glandis; dorsal diverticulum of fossa; site of buildup of smegma

Front 54

What is the indentation along the ventral surface of the corpus cavernous in the horse, which houses the corpus spongiosum surrounding the urethra?

Back 54

Urethral groove

Front 55

What is the term for the widest portion of the glans penis?

Back 55

Corona

Front 56

What is the caudal extension along dorsal surface of penis, located dorsal and lateral to corpus cavenorsum?

Back 56

Dorsal process of the glans

Front 57

What is the blood supply that supplies the prepuce, glans, and cranial portion of corpus cavernosum?

Back 57

External pudendal a. to cranial a. of the penis

Front 58

What artery runs caudally, along dorsal surface of penis and anastomoses with branches of obturator a. (middle a. of penis) and internal pudendal a. (a. of penis)?

Back 58

Dorsal a. of the penis

Front 59

What does the cranial gluteal n. supply in the horse?

Back 59

Leaves ventral border of sciatic n. after passing through greater sciatic foramen; supplies tensor fascia latae, deep gluteal, middle gluteal mm.

Front 60

What does the caudal gluteal n. supply in the horse?

Back 60

Leaves the dorsal border of the sciatic n.; innervates superficial gluteal m. and vertebral heads of semitendinosus and biceps femoris mm.

Front 61

What does the caudal rectal n. supply in the horse?

Back 61

Runs caudoventrally, caudal to pudendal n.; innervates coccygeus, levator ani, and anal sphincter mm.

Front 62

What are the 3 branches of the pudendal n. and what do they innervate?

Back 62

1. Deep perineal n.: mm. of perineum
2. Superficial perineal n.: sensory innervation to anus, vulva, and perineal skin ventrally to udder or scrotum
3. Dorsal n. of penis/clitoris: ischiocavernosus m., corpus cavernosum, corpus spongiosum; or clitoris

Front 63

What is the sheet of strong CT that forms the lateral wall of the pelvis?

Back 63

Sacrosciatic ligament

Front 64

What lymph nodes are located along the ventrak surface of the abdominal aorta and caudal vena cava? What do they drain? Where do they drain into?

Back 64

Lumbar aortic LNs drain the lumbar mm., kidneys, ureters, urinary bladder, and either the testis and epididymis or the ovaries, uterine tube, uterus, and urethra. Drain from the medial and lateral iliac LNs into the thoracic duct.

Front 65

What lymph nodes are located at the origin of the deep circumflex iliac a.? What do they drain? Where do they drain into?

Back 65

Medial iliac LNs drains the caudal abdominal and pelvic walls and the pelvic viscera. Drain from the lateral iliac, deep inguinal, anorectal, and sacral LNs into the lumbar aortic LNs.

Front 66

What lymph nodes are located at the terminal division of the deep circumflex iliac a.? What do they drain? Where do they drain into?

Back 66

Lateral iliac LNs. Drain flank, lateral surface of thigh, and subiliac LNs. Drain into medial iliac LNs.

Front 67

What lymph nodes are located dorsolateral to the caudal part of the rectum in the region between the anus and the root of the tail? What do they drain? Where do they drain into?

Back 67

Anorectal LNs. Drain anal canal, perineum, and tail. Drain into sacral LNs.

Front 68

What lymph nodes are located in the femoral triangle near the superficial inguinal LNs? What do they drain? Where do they drain into?

Back 68

Deep inguinal LNs. Drain from superficial inguinal LNs and popliteal LNs. Drain into medial iliac LNs.

Front 69

What lymph nodes are located between the prepuce and scrotum/udder and trunk? What do they drain? Where do they drain into?

Back 69

Superficial inguinal LNs. Drain external reproductive organs and associated skin and cutaneous mm. of the abdominal wall. Drain into deep inguinal LNs.

Front 70

What lymph nodes are located within the popliteal fossa? What do they drain? Where do they drain into?

Back 70

Popliteal LNs. Drain distal part of pelvic limb. Drain into deep inguinal LNs.

Front 71

What lymph nodes are located against the cranial margin of the thigh, midway between the tuber coxae and patella? What do they drain? Where do they drain into?

Back 71

Subiliac LNs. Drains superficial structures of hip, thigh, and flank. Drain into lateral and middle iliac LNs.

Front 72

What is the prominent crest along the cranioproximal aspect of the tibia?

Back 72

Tibial tuberosity: insertion site of quadriceps femoris mm. and 3 patellar ligaments

Front 73

What bones form the tarsal canal?

Back 73

4th tarsal
Central tarsal
3rd tarsal

Front 74

What artery is a continuation of the external iliac a. after it gives off the deep femoral a.?

Back 74

Femoral a.

Front 75

What does the saphenous a. anastamose with at the proximal end of the cannon bone?

Back 75

Perforating tarsal a. and caudal tibial a.

Front 76

What does the saphenous a. branch into at the proximal end of the cannon bone?

Back 76

Medial and lateral plantar aa. that run distally along the plantarolateral surface of the metatarsus between the interosseus m. and flexor tendons

Front 77

What is the continuation of the femoral a. at the level just proximal to the hock?

Back 77

Popliteal a., which runs between the heads of the gastrocnemius m.

Front 78

What are the branches of the popliteal a.?

Back 78

Cranial and caudal tibial aa.

Front 79

What are the branches of the cranial tibial a.?

Back 79

1. Perforating tarsal a. runs through the tarsal canal towards the plantar surface to anastamose with the saphenous a.
2. Dorsal pedal a. crosses the dorsal hock
3. Dorsal metatarsal a., the major blood supply of the foot

Front 80

What muscles are innervated by the cranial gluteal n.?

Back 80

Tensor fascia latae, deep gluteal, and middle gluteal mm.

Front 81

What muscles are innervated by the caudal gluteal n.?

Back 81

Superficial gluteal, semitendinosus, and biceps femoris mm.

Front 82

What muscles are innervated by the obturator n.?

Back 82

Adductors of the limb: gracilis, pectineus, adductor, external obturator mm.

Clinical signs of damage?

Hint 82

Inability to adductor limb or prevent abduction on a smooth surface

Front 83

What muscles are innervated by the femoral n.?

Back 83

Cranial thigh mm and craniomedial surface of thigh

Clinical signs of damage?

Hint 83

Inability to bear weight on pelvic limb

Front 84

What muscles are innervated by the sciatic n.?

Back 84

Caudal hip and caudal thigh mm.

Clinical signs of damage?

Hint 84

Inability to flex/extend tarsal or digital joints

Front 85

What muscles are innervated by the common peroneal n.?

Back 85

Craniolateral crus mm. and dorsolateral surface of metatarsus

Clinical signs of damage?

Hint 85

Inability to flex tarsal joints or extend digital joints; hoof rests on dorsal surface

Front 86

What muscles are innervated by the tibial n.?

Back 86

Caudal crus mm. and caudal surface of metatarsus

Clinical signs of damage?

Hint 86

Inability to extend tarsal joints or flex digital joints; hock sags when weight-bearing but minimal gait abnormality

Front 87

What are the five retinacula that hold the tendons as they pass over the hock in the horse?

Back 87

1. Proximal extensor retinaculum: long digital extensor, peroneus tertius, and cranial tibial mm.
2. Middle extensor retinaculum: long digital extensor m.
3. Distal extensor retinaculum: long digital extensor and lateral digital extensor mm.
4. Lateral extensor retinaculum: lateral digital extensor m.
5. Flexor retinaculum: deep digital flexor m.

Front 88

What muscle tendons make up the common calcanean tendon?

Back 88

Gastrocnemius
Superficial digital flexor
Biceps femoris
Semitendinosus

Front 89

What acts to steady the calcaneus as it is pulled by the common calcanean tendon?

Back 89

Long plantar ligament

Origin? Insertion?

Hint 89

Extends from plantar surface of calcaneus to the plantar surfaces of the 4th tarsal and metatarsal 4

Front 90

What are the three patellar ligaments in the horse?

Back 90

1. Medial patellar ligament
2. Intermediate patellar ligament
3. Lateral patellar ligament

What sits in the gap between the proximal medial and intermediate patellar ligaments?

Hint 90

Medial ridge of the trochlea

Front 91

Describe the patellar locking mechanism

Back 91

Contract medial mm. of thigh to rotate patella medially.
Patellar fibrocartilage hooks on the tubercle of the medial ridge of the femoral trochlea.
Patella can't glide distally, so joint can't flex.

How does the horse unlock the patella?

Hint 91

Biceps femoris and tensor fascia latae mm. rotate patella laterally

Front 92

What joints make up the hock?

Back 92

1. Tarsocrural: articulation between tibia and talus trochlea
2. Talocalcaneal: articulation between talus and calcaneus
3. "Proximal intertarsal joint": talocalcaneocentral and calcaneoquartal joints
4. "Distal intertarsal joint": articulation between central and 1st, 2nd, and 3rd tarsal bones
5. Tarsometatarsal

Front 93

Bone spavin

Back 93

Osteoarthritis or degenerative joint disease; bony lump on medial aspect of distal tarsus

Front 94

Bog spavin

Back 94

Tarsal hydrarthrosis: chronic distention of tarsocrural joint, causing bulging of joint pouches

Front 95

Curb

Back 95

Inflammation or thickening of long plantar ligament due to injury

Causes superficial digital flexor m. tendon to appear curved

Front 96

Where is the trochanteric bursa?

Back 96

Loacted between the cranial part of the greater trochanter of the femur and the accessory gluteal m.

Front 97

Largest joint capsule in the body?

Back 97

Femoropatellar compartment between femur and patella

Front 98

What joint capsules make up the horse stifle joint?

Back 98

1. Femoropatellar compartment
2. Medial femorotibial compartment
3. Lateral femorotibial compartment

Front 99

Describe the communication between the three joint capsules of the horse stifle joint.

Back 99

Femoropatellar compartment and medial femorotibial compartment typically communicate.

Femoropatellar compartment and lateral femorotibial compartment communicate 25% of the time.

Medial and lateral femorotibial compartments do not communicate

Front 100

Do the tarsal joints communicate?

Back 100

Tarsocrural and proximal intertarsal joints consistently communicate

Proximal and distal intertarsal joints do not communicate

Distal intertarsal and tarsometatarsal joints communicate 40% of time

Front 101

What are the three pouches of the tarsocrural joint?

Back 101

1. Dorsal pouch (largest)
2. Medioplantar pouch
3. Lateroplantar pouch

Front 102

What bursa are associated with the tuber calcanei?

Back 102

1. Subcutaneous calcanean bursa: between tuber calcanei and superficial fascia
2. Calcanean bursa: between tendons of superficial digital fexor and gastrocnemius mm.
3. Cunean bursa: deep to cunean tendon of cranial tibial m.

Front 103

The stifle joint wants to _____. What prevents this?

Back 103

Flex
Patellar locking mechanism prevents hyperflexion

Front 104

The hock joint wants to ____.
What prevents this?

Back 104

Flex
Reciprocal mechanism and patellar locking mechanism prevent hyperflexion

Front 105

The fetlock joint wants to ____.
What prevents this?

Back 105

Extend
Suspensory apparatus and accessory check ligaments prevent hyperextension

Front 106

Describe the suspensory apparatus

Back 106

1. Interosseus m.
2. Proximal sesamoid bones
3. Distal sesamoidean ligaments

Front 107

The pastern joint wants to ____.
What prevents this?

Back 107

Extend
Straight sesamoidean ligament and digital flexor mm. prevent hyperextension

Front 108

The coffin joint wants to ____.
What prevents this?

Back 108

Flex
Extensor branches of the interosseus m. prevent hyperflexion