Quiz 3 Flashcards
Parts of the axial skeleton
skull
hyoid apparatus
vertebrae
sternum
what are hyoid apparatus
little bones in the neck that anchor tongue/throat muscles
Parts of the appendicular skeleton
bones of the limbs and their joints (shoulder and hips)
How many bones are part of the vertebral column
around 50 irregular bones
what are the functions of the vertebral column
they aid in locomotion
- link thoracic and pelvic limbs
- provide direction and support the locomotor system
protect the spinal cord
what are the 5 groups of vertebrae
cervical thoracic lumbar sacral caudal
number of vertebrae in the dog
C7-T13-L7-S3-Cd20
What is special about sacral vertebrae
they are fused
what is special about the caudal vertebrae
number varies between breeds
difference between cranially and caudally body vertebrae
cranially: convex
caudally: concave
what are intervertebral disks
fibrous joints between bodies
what are the components and function of intervertebral disks
components: nucleus pulposus and anulus fibrous
function: absorb shock and allow movement
what are the parts of the vertebral arch
pedicles-basal part
laminae-dorsal part
what makes the vertebral foramen
all VArches + body
what makes the vertebra canal
all VForamina
what is the intervertebral foramina
small holes through which pass the spinal nerve and blood vessels
where are the spinous processes
located dorsally (spine)
where are the transverse processes
project laterally from the area where the arch joins the body
what is the transverse foramen
short canal that passes obliquely through the transverse process and contain vertebral arteries and veins
where are the articular processes
2 on each side of vertebra that articulate with ribs
what are the pairs of articular processes
cranial pair: dorsal-medial
caudal pair: ventral-lateral
what are the parts of a typical vertebra
o Body o Vertebral arch o Right/left pedicles o Righ/left laminae o Transverse processes o Spinous processes o Articular processes
what forms the vertebral foramen
body of the vertebral arch
what forms the vertebral canal
all vertebral foramen joined together
what is the atlas
C1 - 1st cervical vertebra
parts of the atlas
- transverse process from the wings
movement of the atlas
hinge joint: yes movement
what is the axis
C2: 2nd cervical vertebra
parts of the axis
elongated spinous process
movement of the axis
pivot joint: no movement
articulation of atlas:
Cranial articular fovea articulates with occipital condyles of skull to form the atlanto-occipital joint
articulation of axis:
o Dens of axis articulates with fovea dentis of atlas to form atlanto-axial joint
shapes of the thoracic vertebrae
- 1st nine vertebrae have a spine (spinous process)
* 12th to 13th different shape
what are the thoracic vertebrae articulate to
the ribs
what attaches to the mamillary process
epaxial muscles of the transversospinalis system attach to them
anticlinal vertebra characteristics
point in caudal thoracic vertebral column where vertebral anatomic features change
spinous process of anticlinal vertebra characteristics
perpendicular to the body and the preceding vertebrae incline caudally
Position of the spinous process in different species
horse: T16
big/medium dogs: T11
small dogs: T10
Ox T11 to T13
Processes of lumbar vertebrae
spinous process
transverse process
characteristic of spinous process of the lumbar vertebrae
blunt
characteristic of transverse process of the lumbar vertebrae
prominent and directed cranially
what are the sacral vertebrae
- sacrum results from the fusion of the bodies and processes of 3 vertebrae
where is the sacrum
between the ilia
what is the sternum
8 unpaired segments of sternebrae
how are sternebrae joined
by intersternal cartilages
what is the 1st sternebrae
manubrium
what is the 8th sternebrae
xiphoid process
characteristics of ribs 1 to 9
articulate with sternum
characteristics of ribs 10 to 12
unite with each other to form the costal arch, “asternal ribs” that the costal cartilage attached to other costal cartilage rather than the strenum
characteristic of rib 13
floating rib, ends in muscle of thoracic wall
vertebral formulas by species
canine
- cervical 7, thoracic 13, lumbar 7, sacral 3
equine
- cervical 7, thoracic 18, lumbar 6, sacral 5
bovine
- cervical 7, thoracic 13, lumbar 6, sacral 5
how are ribs numbered
rib number corresponds with the caudal vertebra with which it articulates
what are true ribs
the sternal ribs, their cartilage attaches with the sternum
true ribs in dogs cats and horses
o Dog/cat: 9 pairs
o Horse: 8 pairs
what are false ribs
the asternal ribs or costal arch, their cartilage doesn’t articulate with the sternum
false ribs in dogs cats and horses
o Dog/cat: 3 pairs
o Horse: 10 pairs
what are floating ribs
their cartilage doesn’t attach to adjacent cartilage, they are a false asternal rib
floating ribs in dogs cats and horses
o Dog/Cat/Horse: 1 pair
where is the supraspinous ligament
runs along the tips of the spinous process from T1 to Caudal3
where is the interspinous ligament
in between spinous processes
use of the nuchal ligament
o Provides an elastic force that permits the lowered head to be raised relatively easily
nuchal ligament in dogs
Strong band connective tissue between the spinous processes of C2 to T1
nuchal ligament in horse/ox
extensive and consists of funicular (arising from the skull) and lamellar parts (strong connective tissue arising from T2/T3 and inserting into C2 to C6) that relieves the epaxial muscles when lifting and supporting the head
nuchal ligaments in cats/pigs/some primates
absent
what are the types of axial muscles
epaxial muscles
hypaxial muscles
what are epaxial muscles
lie dorsal to transverse processes of T and L vertebrae, responsible for extending or dorsally bending cervical vertebrae.
what are hypaxial muscles
located ventral to transverse process and include abdominal and thoracic muscles
characteristic of ligamentum nuchae
Pale yellow with a thick cord-like funicular part and a flat sheet-like or lamellar part
what happens to ligamentum nuchae when the head is cut
When the head is removed, elasticity of ligament causes the neck of the carcass to curve dorsally
what is the ligamentum nuchae
Very strong elastic ligament in the dorsal midline of the neck
use of ligamentum nuchae
Relieves the animal of the weight of its head
Without it, the head of the standing animal would droop between its forelimbs
location and use of hypaxial muscles
Located ventral to the transverse processes
Are essentially flexors of the vertebral column
hypaxial muscles of the neck
longus capitis
longus colli
what is the longus capitis
lies on the lateral surface of the cervical vertebrae
what is longus colli
Covers the ventral surfaces of the vertebral bodies from T6 to C1
Muscle must be reflected to expose the cervical intervertebral discs for surgery purposes
hypaxial muscles of the thorax
o Scalenus and rectus thoracis
o Serratus ventralis (cervicis-thoracis)
o Serratus dorsalis (cranialis-caudalis)
o External intercostals: fibers run caudoventrally
o Internal intercostals: fibers run cranioventrally
muscles of the abdominal wall
external abdominal oblique
internal abdominal oblique
transversus abdominis
rectus abdominis
characteristics of the external abdominal oblique
Ventrally forms wide aponeurosis inserting on linea alba (midventral raphe) and prepubic tendon inguinal canal
characteristics of the internal abdominal oblique
Inserts on costal arch, rectus abdominis, linea alba, prepubic tendon
Muscle fibers caudal border forms cremaster m.
characteristics of transverse abdominis
Fibers run transversely: fibers sparse with ventral branches of T13, L1, L2, L3 spinal nerves
Caudal portion fuses with linea alba and prepubic tendon
characteristics of rectus abdominis
o Extends from pubis (I) to sternum (O)
o Distinct transverse tendinous intersections
what is the umbilical region of rectus abdominis
external lamina of the sheath of the rectus abdominis muscle is formed by the fused aponeurosis of external and internal abdominal muscles
what forms the internal lamina
formed by aponeurosis of transversus abdominis muscle
use of the muscles of the abdominal wall
urination, defecation, parturition, respiration, and locomotion when they contract.
what is the prepubic tendon in domestic animals
prepubic tendon is a strong fibrous structure attached to the cranial border of the pubic bones (pectin of pubic bone) between the symmetrical iliopubic eminences
what does the prepubic tendon of domestic mammals allow
allows the attachment of linea alba and the tendons of abdominal muscles to the pubis
what is the linea alba
fibrous cord formed by the joining of the aponeuroses of the abdominal muscles from both sides.
where is the linea alba
. Its on the ventral midline, extending fom the xiphoid cartilage to the pelvic symphysis. Site of incision for abdominal surgery as it is avascular.
what is the inguinal canal
- The passageway for abdominal structures out of the abdomen.
- It’s a collapsed canal between the deep and superficial inguinal rings.
what is the link of testicles with the inguinal canal
• The testicle descends through the inguinal canal just before or after birth to reach the scrotum.
what is in the female inguinal canal
vaginal process
o Envelops the round ligament of the uterus
what is in the male inguinal canal
vaginal tunic
o Cremaster muscle (thermoregulation system)
o Spermatic cord
what is in the spermatic cord
Ductus (vas) deferens Testicular artery and nerve Pampiniform plexus Sympathetic and parasympathetic nerve fibers Lymphatic vessels
what passes through the inguinal ring in both sexes
• In both sexes the external pudendal artery and vein and the genitofemoral nerve also pass through the inguinal ring
where are the epaxial muscles
- These muscles lie on or above the vertebral column (dorsal to transverse process).
- The epaxial muscles extend the vertebral column (when both sides act together) and laterally flex the vertebral column (when one side contracts).
what are the muscle systems of the epaxial muscles
transversospinalis system
longissimus system
illiocostalis system
muscles of the transversospinalis system
- splenius
- semispinalis capitis (biventer cervicis and complexus)
muscles of the longissimus system
- thoracis et lumborum
- cervicis
- capitis
muscles of the illiocostalis system
- lumborum
- thoracis
muscles of inspiration in neck/trunk
- sternocephalicus
- scalenus rectus thoracis
- serratus dorsalis (cranial)
- external intercostal muscles
- diaphragm
muscles of expiration in neck/trunk
- external and internal abdominal oblique
- transversus abdominis
- serratus ventralis
- serratus dorsalis (caudal)
- internal intercostals muscles
- rectus abdominis
- diaphragm
location of most nerves
Most nerves extend from the brain or spinal cord to carry information to the muscles and organs.
location of major nerves
• Twelve pairs of major nerves in the head arise from the brain and emerge through holes in the skull to reach their target areas such as the muzzle, eyeball, teeth and tongue.
what are the cranial nerves
nerves of the head
what are the peripheral nerves
nerves to the rest of the body arise in pairs from the spinal cord and exit from the vertebral column through spaces between the vertebrae
what does the function of a nerve determine
• Function determines if nerves are classified as sensory (dorsal branch), motor (ventral branch) or mixed.
what are sensory/afferent nerves
carry information from the periphery of the body to the spinal cord and brain
what are motor/efferent nerves
transmit impulses from the brain and spinal cord to the periphery.
what are mixed nerves
composed of both motor and sensory fibers and transmit messages in both directions.
what is a neuron
basic unit of the nervous system
what are the 2 characteristic properties of neurons
o Capable of responding to stimulation (irritability)
o Able to conduct impulses (conductivity)
what are the parts of neurons
body
dendrites
axon
nerve terminals
what is the neuron cell body
contains the nucleus of the cell
what are dendrites
thread-like extensions that typically branch into tree-like processes.
They receive stimuli from other nerves or from a receptor organ such as the skin or ear and transmit them to the axon.
what is an axon
is a long outgrowth of the cell body that carries impulses away from the cell body to another neuron, thereby stimulating an action.
what is a nerve (axon) terminal
specialized structure at the end of the axon that used to release neurotransmitters (chemicals: acetylcholine norepinephrine, relaying electrical signals) and communicate with other neurons or target area.
spinal cord segments in dogs/cats
C8-T13-L7-S3-Cd5
36 total
spinal cord segments in bovine
C8-T13-L6-S5-Cd5
37 total
spinal cord segments in horse
C8-T18-L6-S5-Cd5
42 total
spinal cord segments in swine
C8-T14/15-L6/7-S4-Cd5
38 total
spinal cord segments in humans
C8-T12-L5-S5-1 coccygeal
31 total
5 main groups of spinal nerves
- Cervical supplying the neck region
- Brachial supplying the thoracic limb
- Thoracolumbar supplying the thorax and abdominal region
- Lumbosacral supplying the pelvic limb and perineum
- Caudal supplying the tail
what happens to intercostal arteries
• Arteries of each intercostal space divide into ventral and dorsal branches (derived from dorsal intercostal arteries)
where to dorsal intercostal arteries and veins pass?
• Dorsal intercostal arteries and veins pass ventrally where they anastomose (the union of parts of branches as blood vessels so as to intercommunicate or interconnect) with ventral intercostal branches (coming from the internal thoracic arteries and veins)
what is the pelvic symphysis
o Join the pubis and ischium of the 2 hip bones.
o It’s a secondary cartilaginous joint that ossifies with age
o Ossification begins at the pubis and moves caudally
what is the sacro iliac joints
o Combine a synovial join with an adjacent area of fibrous union.
o Thought to allow a firm joint with a degree of shock absorption
what is the sacrotuberous ligament
o Stout cord that runs from the transverse processes of the last sacral and 1st caudal vertebrae to the lateral angle of the ischiatic tuberosity
o Serves as a point of attachment for biceps femoris muscle
what is the hip
o Ball and socket joint whose main movement are flexion and extension
what is the ligament of femoral head
o Thick band of collagenous tissue that extends from the acetabular fossa to the fovea capitis
o Prevents dislocation of hip joint
what is the transverse acetabular ligament
o Small band that extends from one side of the acetabular notch to the opposite side
o Continues the acetabular lip which deepens the acetabulum to keep the femur head solidly in place
the ligaments of the stifle/knee
- Cranial cruciate ligament
- Meniscofemoral ligament
- Caudal cruciate ligament
- Transverse ligament
- Lateral and medial femoroplatellar ligament
- Lateral collateral ligament
- Medial collateral ligament
- Patellar ligament
3 bones of the knee joint
o Thigh bone/femur
o Shin bone/tibia
o Kneecap/patella
