Vertebral Column and Back Musculature Flashcards
what is the skeleton?
structural support that provides system of levers for muscular movement as well as protects soft tissues/organs
what makes up the axial skeleton?
skull/cranium,
vertebral column
ribs and sternum
what makes up the appendicular skeleton?
limb bones
pelvis
scapula
clavicle –> reduced in animals to increase movement range
what are joints?
articulations either firmly unite bones or allow specific movements between bones
what is flexion?
movement that REDUCES the angle between bones
what is extension?
movement that INCREASES the angle between bones
describe the cervical region characteristics
-spinous process is small
-transverse process splits into dorsal and ventral tubercles
describe the thoracic region characteristics
-articulate with the ribs
-prominent spinous process
-transverse process –> short
describe the lumbar region characteristics
-transverse process cranioventrally oriented
-articular processes in sagittal plane
-blunt spinous process
describe the sacrum characteristics
-3-5 fused vertebrae
-articulate with ilium at sacroiliac joint
what are the intervertebral discs? where are they positioned?
-between vertebral bodies
-are compressible and absorb shock
-allow movements along multiple axes
what do plane/synovial joints allow? what are they?
-allow for sliding movements between articular processes of adjacent vertebrae
-enclosed capsular joint containing a smooth, viscous lubricant
what are anulus fibrosus?
-concentric rings of fibrocartilage
-usually thinner dorsal and sometimes also lateral
what are nucleus pulposus?
-central core of IV disc
-semifluid at birth –> dehydrates with age
what do ligaments do?
limit excessive movement across joints
what is the vertebral canal formed by?
sequence of vertebral foramina
what is the purpose of the verterbal column?
protects the spinal cord
how do dorsal rami travel?
dorsally
how do ventral rami travel?
ventrolaterally
which is bigger: dorsal rami or ventral rami:
ventral rami
what do epaxial muscles do and where are they found?
-support vertebral column and are a major part of locomotion
-found along a narrow region of the back and neck
what does origin mean?
(usually) the proximal end of a muscle that is fixed during contraction
what does insertion mean?
(usually) the distal end of a muscle that attaches to the mobile portion of bone
what is the nuchal ligament?
supports much of mass of head without muscular effort
site of muscle attachment
what does innervation mean? (N)
the peripheral nerve that provides motor innervation to and takes sensory innervation from a muscle
what does action mean? (A)
product of the movement generated by muscle contraction
what are hypaxial muscles?
function in limb movement and stability –> locomotion
positioned superficial to the epaxial muscles
what makes up the epaxial muscles?
iliocostalis system (most lateral)
longissimus system
transversopinalis system (semispinalis) –> most medial
what makes up the transversospinalis system?
spinalis (capitis, cervicis)
semispinalis (capitis, cervicis) –> found near head, neck and thorax
multifidus –> closer to lumbar region
name the O of the semispinalis cervicis
spinous processes of the first 3 thoracic vertebrae; nuchal ligament
name the I of the semispinalis cervicis
nuchal crest and mastoid process
name the N of the semispinalis cervicis
dorsal rami of spinal nerves along the extent of the muscles
name the A of the semispinalis cervicis
extend neck and head; assists in turning neck laterally
what is the thoracolumbar fascia?
is a deep, dense fascia that gives attachment to multiple muscle groups
also provides stability and support to the caudal lumbar region
what do dorsal rami innervate?
the epaxial muscles
what do ventral rami innervate?
the hypaxial muscles and all other somatic muscles of the back
