The Back Flashcards
Vertebral column
7 cervical (posture) 12 thoracic (weight-bearing) 5 lumbar (protects spinal cord) 5 saccral (contributes to ribs) 1-2 coccygeal (attachment of trunk muscles)
Primary curvatures
In utero
Kyphosis
Still in thoracic and saccral regions
Secondary curvatures
Develops as you grow
Lordosis
Still in cervical and lumbar regions
Develops once infant can lift head and stand to walk
Characteristic features of cervical vertebrae
Bifid spinous process
Transverse foramina
Triangular vertebral foramen
Characteristic features of thoracic vertebrae
2 demi facets for articulation the heads of 2 different ribs
Costal facet on transverse processes for articulation with shaft of one rib
Spinous process is oblique and long extending posteriorly and inferiorly
Circular foramen
Characteristic features of lumbar vertebrae
Large vertebral body
Triangular foramen
Short spinous process
sacrum
5 fused vertebrae sacral hiatus (arch at bottom) Median, intermediate and lateral crests
Coccygeal vertebrae
Varies in number between individuals (1-4)
Fused in some people
Some do not ossify
Atlas
C1
Superior facet for articulation with occipital condyle
Contains facet for articulation with axis
Groove for vertebral artery
Axis
C2
Ondontoid process/dens
Superior articular facets that articulate with inferior facet of C1
alar ligament from sides of dens to sides of foramen magnum
transverse ligament that keeps dens close to anterior arch
Role of C1 and C2
Rotation of head and neck at atlantoaxial joint
Joints of vertebral column
Zygopophaseal joints: between facets of vertebrae above and below
Symphysis: between invertebral discs
Intervertebral disc
Central nucleus pulposus
- gelatinous
- absorbs compressive forces between vertebrae
- collagen content and dehydration increases with age: contributes to shrinking
Outer anulus fibrosus
- very strong concentric lamellae of fibrocartilage
- attached and kept in place by anterior and posterior longitudinal ligaments
Herniated disc
Slipped disc- presses on nerve structures
Most common in posterolateral direction and in lumbar region
Possible compression of spinal cord/cauda equina/emerging spinal nerve
Anterior-atlanto and atlanto-occipital membranes
Continues as anterior longitudinal ligament:
- limits extension
- extends from atlas to sacrum
Tectorial membrane
From foramen magnum to C2
Continues as posterior longitudinal ligament
-resists hyperflexion
-extends from C2 to sacrum
Which ligament is found between vertebral lamina? What is its function?
Ligament flava
- limits flexion
- supports curvatures
- continuation from atlanto-axial and atlanto-occipital membranes
Which ligament is found between transverse processes?
Intertransverse ligament
Which ligament is found between the tips of spines?
Supraspinous ligament from C7 to sacrum
Continuation of ligament nuchae from posterior edge of foramen magnum and C7
Cruciate ligament
Transverse + superior and inferior longitudinal fascicles
- helps hold C1 and C2 together
- prevents excessive movement between altas, axis and occiput
What supplies vertebrae?
Anastomic rings from vertebral arteries and posterior, intercostal and lumbar branches of aorta
Venous plexus, internal and external coalesce drain to veins
Basivertebral veins on the body of the vertebrae
Extrinsic muscles
Superficial
Involved in movement of upper limbs and thoracic wall
Innervated by anterior rami of spinal nerves
Intrinsic muscles
Deep between spinous processes and angle of ribs
Provides support/movement in resistance to gravity
Involved in movement in vertebral column
Innervated by posterior rami of spinal nerves
Function of trapezius
Extends neck
Retracts scapulae
Upper fibres elevate shoulders in abduction
Lower fibres depress shoulder
Function of latissimus dorsi
Shoulder extension and adduction
Function of rhomboid major and minor
Scapular retraction and elevation
Function of serratus posterior superior
Inspiration
Function of serratus posterior inferior
Expiration
Superficial muscle and function
Splenius capitis and cervicis together: extend the neck alone: involved in lateral flexion and rotation
Intermediate muscle and function
Illiocostalis (cervicis, thoracis, lumborum)
Longissimus (capitis, cervicis, thoracis, lumborum)
Spinalis (capitis, cervicis, thoracis)
