Skeleton + anatomical planes Flashcards
how many cervical vertebrae do mammals (typically) have?
7
how many cervical vertebrae do bird have?
8-25
how many thoracic vertebrae do carnivores have?
13
how many thoracic vertebrae do horses have?
18
how many thoracic vertebrae do cows have?
13
how many thoracic vertebrae do goats/sheep have?
13
how many thoracic vertebrae do pigs have?
14-15
how many thoracic vertebrae do birds have?
3-10
how many lumbar vertebrae do carnivores have?
7
how many lumbar vertebrae do horses have?
5-6
how many lumbar vertebrae do cows have?
6
how many lumbar vertebrae do goats/sheep have?
6
how many lumbar vertebrae do pigs have?
6
in birds, what happens to the lumbar and sacral vertebrae?
they become fused into the synsacrum
how many sacral vertebrae do carnivores have?
3
how many sacral vertebrae do horses have?
5
how many sacral vertebrae do cows have?
5
how many sacral vertebrae do sheep/goats have?
sheep: 4
goats: 5
how many sacral verterbrae do pigs have?
4
how many caudal vertebrae do carnivores have?
15-25
how many caudal vertebrae do horses have?
~20
how many caudal vertebrae do cows have?
18-20
how many caudal vertebrae do sheep/goats have?
16-18
how many caudal vertebrae do pigs have?
20-23
how many caudal verterbrae do birds have?
5-6
In general, what happens to the variability in limb bones as you move distally down the limb?
they become more variable in the presence/absense of them
what are the anatomical planes?
median (sagittal), dorsal, transverse
what are the anatomical axes that you use to give directions on an animal?
mediolateral (medial + lateral)
dorsoventral (dorsal + ventral)
transverse (proximal + distal; cranial/rostral + caudal)
what makes up the appendicular skeleton?
pectoral girdle/limb + pelvic girdle/limb
what makes up the axial skeleton?
cranium, vertebral column, ribcage
label this diagram
1: body
2: pedicles
3: laminae
4: transverse processes
5: spinous process
2 + 3: neural arch
what is the difference between skeleton and bone?
skeleton is a system, bone is a tissue/individual element
what is the difference between bone and bones?
bone = tissue component
bones = actual organs
what are the two types of bone (material) within a single bone (structure)? where are they located?
cortical bone –> on the cortex (outside) of the bone
cancellous/spongy bone –> inside the bone
what are bones’ physioloical functions?
homeostasis (Ca, P, ions (pH), fats) and hematopoiesis (producing blood cells)
what are bones’ mechanical functions?
protection, passive support, motion
what are the two types of bone growth?
intramembranous and endochondral
what happens during intramembranous bone growth?
individual bones grow directly in connective tissue
what happens during endochondral bone growth?
cartilage precursor forms in future anatomical position
cartilage cells calcify and form “centers of ossification”
bones grow by establishing growth plates
what are the cranial and caudal articular processes?
on vertebrae, they are on the cranial/caudal sides of the vertebrae, they are what articulate with the vertebrae ahead/behind them
what is a diaphysis?
shaft of a bone
what is a sulcus?
groove
what is a tuberosity?
roughened, elevated bump/ridge
what are sesamoid bones?
bones embedded in tendons, not directly connected to other bones
how does naming ribs work?
ribs are named for the thoracic vertebrae that is caudal to it
what are flexsion and extension?
flexion is movement resulting in a decrease in the angle of joints
extension is movement resulting in an increase in the angle of joints
describe the general anatomy of cervical vertebrae (not atlas and axis)
short spinous processes, branching transverse processes, articular processes in DV/CC plane
what is the atlas? describe its anatomy
C1
no body, short spinous process, large + flat transverse processess, condyles cranially
what is the axis? describe its anatomy
C2
long + huge + flat spinous process, transverse processes virtually nonexsistent
has dens
what is the dens? what is its function?
the dens is on the axis (C2) and fits against ventral atlas (C1) arch
permits axial rotation of the head
describe the general anatomy of thoracic vertebrae
long spinous processes, stubby transverse processes, costal facets, ribs attached
articular processes permit axial rotation, DV F/E (cranially) and ML F/E (caudally)
what happens to the articular processes as you move through vertebrae cranially to caudally?
the facets go from DV to ML
are ribs made of bone, cartilage, or both?
both
dorsal is bony, ventral is cartilage
what is a costochondral juntion?
where the bone meets the cartilage on a rib
describe the dorsal side of a rib
head –> has 2 facets for articulation with 2 thoracic vertebrae
tubercle –> has facet for articulation with transverse process of the vertebrae caudal to it
label this image
1: tubercle
2: head
3: neck
4: angle
5: body
6: costochondral junction
7: cartilage
what are true/sternal ribs?
articulate directly with the sternum
what are false/asternal ribs?
articulate indirectly to sternum via cranial costal cartilage
what are floating ribs?
ribs that don’t articulate directly or indirectly with the sternum
what is the manubrium?
cranial end of the sternum, may be slightly larger sternebrae
what are sternebrae?
little bones that make up the body of the sternum (like vertebrae)
what is the xiphoid process?
caudal end of the sternum, usually the smallest portion with a cartilage end
describe the general anatomy of lumbar vertebrae
longer body, short spinous process, long + flat transverse process, articular processes are mainly ML
facets permit DV and ML F/E (little axial rotation)
what is the sacrum?
fused sacral vertebrae
what is the sacroiliac joint?
where the sacrum articulates with the ilium
why is the sacrum fused?
for stability since most propulsion comes from the hindlimb
describe the anatomy of caudal vertebrae. what happens as you move caudally?
cranially, they are like mini-lumbars. cranial caudal vertebrae haev hemal arch
caudally, they are rod like
what is the hemal arch?
arch where the caudal artery passes through. seen in caudal vertebrae located cranially
what are the three bones of the pelvis?
ilium, ischium, pubis
what is the os coxa?
the fusion point of the ilium, ischium, and pubis
what is the acetabulum?
where the head of the femur articulates with the pelvis
what is the pubic symphysis?
the point at which the two os coxae fuse
how does the pectoral girdle articulate with the rest of the skeleton? why?
indirectly through muscular articulation
need greater range of motion
what are the components of the pectoral girdle (not limb)? where is there variation?
scapula and clavicle
no clavicle in domestic species, although cats + dogs have it present as a small rod embedded in muscle
primates have clavicle
what is the advantage of having a clavicle? what is the advantage of NOT having a clavicle?
having: greater stability for climing/arboreal locomotion
not having: greater range of motion, esp. in sagittal plane
in the humerus and femur, what is the advantage of having a rounder proximal head?
greater range of motion
what type of motion is permitted by the proximal head of the femur/humerus? what about the distal articular surfaces?
head: greater range of motion
distal ends: flexion/extension
how many digits do ruminants have?
2
how many digits do horses have?
1
describe the anatomy of the distal limb skeleton of ruminants
metacarpals/metatarsals III and IV fuse, phalanges of III and IV digits still separate
metacarpal/metatarsal V present vestigially, greatly reduced
describe the anatomy of the distal limb in horses
single metacarpal/metatarsal (III), reduced metacarpals/metatarsals II and IV
what is the cannon bone?
the fused metacarpals/metatarsals III and IV in ruminants
metacarpal/metatarsal III in horses
what are the splint bones?
the reduced metacarpals/metatarsals II and IV in horses
what is the calcaneous?
the heel bone
the calcaneus is to the hindlimb as the ___ is to the forelimb
accessory carpal
what is the advantage of lengthening limbs?
increased stride length –> cursorial species
why do cursorial species tend to lose/fuse bones in distal limbs?
to reduce the weight of the distal limb to reduce the cost of swinging leg while running
what movements of the spine are facilitated by the lumbar vertebrae? what about the thoracic vertebrae?
lumbar: F/E in dorsal plane - mediolateral movement
thoracic: F/E in median plane - dorsoventral movement
why do the thoracic vertebrae have such short transverse processes?
because the ribs articulate with the thoracics near/on the transverse processes
what are the transverse foramina? what are they used for?
holes in the vertebral body of cervicals for passageway of arteries, veins, and nerves
describe how a rib articulates with the vertebral skeleton
the tubercle articulates with the transverse process of the T verterbrae caudal to it
the head has 2 facets - one goes into the costal fovea/facet of the vertebrae cranial to it, the other goes into the costal fovea of the vertebrae caudal to it
describe the sternum of carnivores
sternebrae are obvious and connected by cartilage. they are rod-like
describe the sternum of bovines
sternebrae are less obvious, but still there. they are quite fat
describe the sternum of horses
sternebrae have fused
which dom. spp have an acromion? which spp don’t?
have: carnivores + cows
do not have: horses + pigs
which species has the roundest humeral head? which species has the least round humeral head?
what does this mean for movement?
roundest: canids/carnivores
least round: horses
canines capable of some abduction at shoulder, horses cannot do this
what is different about the tubucular grooves in a horse?
there is an intermediate tubercle –> splits the groove in two
what type of motion is permitted by the joint between the trochlea and trochlear notch in the humerus/ulna?
flexion/extension
what feature of the forelimb prevents hyperextension of the elbow joint?
olecrannon process of the ulna
are pronation and supination possible in ungulates? why or why not?
no
for pro/sup, there needs to be axial rotation of the radius over the ulna. ungulates have fused the radius and the ulna
what is the function of the accessory carpal bone?
increases mechanical advantage of wrist flexors, increasing their ability to generate torque in flexion
label this picture
A: pubis
B: ischium
C: ilium
what are the intervertebral foramina?
located in the sacrum, they are holes for nerves, arteries, veins to pass through
how do the condyles of the equine femur differ from each other ?
the medial condyle is larger and has a marked ridge proximally
what bone sits in the trochlea/patellar groove?
patella
what type of bone is the patella?
sesamoid
what is the stifle?
knee joint
what is the hock?
ankle joint
the reciprocal surfaces of the distal femur and the proximal tibia are not congruent. what does this mean for the stifle?
the stifle joint is not very stable
what is the dewclaw?
the vestigial metatarsal I that is sometimes present in canines
where is the subscapular fossa?
on the scapula, on the opposite side of the spine
label this image
what is it and what animal is it from?
A: caudal angle
B: acromion
C: scapular notch
D: infraspinous fossa
E: supraspinous fossa
F: spine
G: cranial angle
H: supraglenoid tubercle
I: cranial border
J: caudal border
K: glenoid fossa
canine scapula
what animal is this bone from?
horse
what animal is this bone from?
cow
label this image
what bone is this, what direction is it, and what animal is it from?
A: teres major/medial tuberosity
B: head
C: lesser tubercle
D: intermediate tubercle
E: greater tubercle
F: deltoid/laterla tuberosity
G: trochlea
humerus, cranial, horse
label this image
what bone is this, what animal is it from, and what direction is it?
A: deltoid/lateral tuberosity
B: head
C: lateral epicondyle
D: olecranon fossa
E: medial epicondyle
humerus, horse, caudal
what bone is this, what animal is it from, and what direction is it?
what is structure A?
humerus, cow, cranial
intertubercular groove
label this image
what is this and what animal does it come from?
A: ischial tuber
B: obturator foramen
C: iliac crest
D: ilium
E: acetabulum
F: ischium
G: pubis
pelvis, dog
what is the circled structure? where is it located?
coxal tuber
on the end of the ilium of cows and horses
label this image
which bone is lateral and which bone is medial?
A: ulna
B: radius
C: olecranon/olecranon process
D: trochlear notch
E: lateral styloid process
F: head of radius
G: medial styloid process
radius = medial
ulna = lateral
what is the circled structure?
what animal is this from?
what bone is the circled structure located?
lateral styloid process
cow
ulna
label this image
what limb is it from? (fore or hind?)
A: distal phalanx
B: navicular
C: intermediate phalanx
D: proximal phalanx
E: proximal sesaoid bone
forelimb
what type of bone is the navicular?
sesamoid
label this diagram
what bone is this and what animal does it come from?
A: greater trochanter
B: femoral head
C: trochanteric fossa
D: medial condyle
E: lateral condyle
F: lesser trochanter
femur, dog
what is the name of structure A?
patellar groove/trochlea
label this image
what bone is it and from what animal?
A: lesser trochanter
B: greater trochanter
C: 3rd trochanter
femur of horse
label this bone
what bone is it?
A: tibial plateau
B: medial malleolus
C: intercondylar eminence
tibia
what bone is this and what is structure A?
tibia, tibial tuberosity
how can you tell the difference between a horse tibia/fibula and a cow tibia/fibula?
cow has a bit of the proximal fibula present, horse fibula has completely fused with tibia
label this image
what animal is it from?
A: fibula
B: tibia
C: intercondylar eminence
D: medial malleolus
E: lateral malleolus
cow
label this diagram
what bone is this and what animal is it from?
A: tibial tuberosity
B: medial malleolus
cow tibia/fibula
label this diagram
A: calcaneous
B: lateral tarsal
C: talus
D: central tarsal
E: tarsals
F: metatarsals
