Chapter Three: The Spine Flashcards
Vertebral column
-7 cervical vertebrae (in the neck)
-12 thoracic vertebrae (in the thorax)
-5 lumbar vertebrae (in the lower back)
-5 fused sacral vertebrae (in the sacrum)
-1 or 2 coccygeal vertebrae (in the coccyx or tail bone)
Vertebral structure main parts
-body (and a disc)
-vertebral arch
Vertebral body and disc
-bodies articulate vertically with each other via intervertebral discs
Annulus fibrosus (part of disc)
outer fibrocartilage cortex
Nucleus pulposus (part of disc)
-pulpy inner core (medulla)
Vertebral disc labelling
Vertebral arch elements
-pedicles
-lamina
-vertebral foramen
-vertebral canal
-infravertebral notch
Pedicles
Bony processes that attach to the body on each side
Lamina
Connect to the pedicles anteriorly and to each other posteriorly
Vertebral foramen
Made up of the arch and posterior aspect of the vertebral body (hole)
Vertebral canal
Vertical cylinder made up of all the vertebral foramina, where spinal cord runs through
Infravertebral notch
Formed by the body and the vertebral arch, where pedicle meets pedicle.
Processes of the vertebral column
-articular processes
-transverse processes
-spinous processes
Articular processes
-inferior articular process and superior articular process
-they form the joint (apophyseal)
Transverse processes
-serve as attachments for muscles and in the thorax also as attachments for ribs
-stick out to the sides
Spinous processes
-single process that projects backwards
Intervertebral foramen
-where the spinal nerves enter and exit the column
-very critical if damaged
Vertebrae labelling
The atlas
-C1
-designed to hold up the skull
-has a larger vertebral foramen, but little to no body
The axis
-C2
-prominent feature is the dens (looks like a finger pointing upwards)
-this fits into the extra space of C1
-permits rotation of the head
Transverse ligament
-holds dens to atlas
-snaps when a person is hung
Atlanto-occipital joint
-where C1 attached to the occipital condyles
Typical cervical vertebrae
-oval and thin
-spinous processes are bifid (split in 2 posteriorly)
-discs are thick because neck is flexible
-contain transverse foramen
Transverse foramen (in cervical vertebrae)
-for the passage of the vertebral artery and vein
Thoracic vertebrae
-thicker heart shaped body
-apophyseal joints are oriented coronally (more forward)
-articular facets to accommodate the joints with heads of ribs
Transverse costovertebral joints
-where ribs articulate with facets of thoracic vertebrae
Lumbar vertebrae
-very thick and kidney shaped
-thick discs because relatively flexible (most likely to be damaged)
-facet joints face medial laterally
Sacrum
-5 fused vertebrae
-sacral foramina (usually 4 on each side)
-medial sacral crest (looks like an ear), is where hip girdle articulates
Sacroiliac joint
-holds lower limbs (pelvic girdle) to vertebral column
Sacrum labelling
Curvatures of the vertebral column
-cervical (secondary)
-thoracic (primary)
-lumbar (secondary)
-sacral (primary)
Primary vs secondary curvatures
-primary: present in the fetus
-secondary: develop after birth
Kyphosis
-exaggeration of the thoracic curvature
-hunch back
Lordosis
-excessive curvature in the lumbar region
-swayback
-ruptured disc is common because there is too much pressure on these discs
Scoliosis
-coronal malcurvature of the spine to one or both sides
Curvatures of the spine labelling
Anterior longitudinal ligament
-runs down the anterior aspect of the vertebral bodies
Posterior longitudinal ligament
-runs down the posterior (dorsal) aspects of the vertebral canal
Ligamentum flavum
-join the laminae of the vertebrae
-elastic tissue
Interspinous ligaments
-connect adjacent spinous processes
Supraspinous ligaments
Ligamentum nuchae
-where supra and inter spinous ligaments are reinforced
-elastic tissue
-keeps your head up without using much effort
-where they aim for in bull fights
Intertraverse ligaments
-connect the transverse processes with eachother
Ligaments of the vertebral column labelling
Muscles of the neck
-splenius capitis
-semispinalis capitis
Splenius capitis
-origin point: lower cervical and upper thoracic vertebral arches
-insertion point: mastoid process
Semispinalis capitis
-origin point: lower cervical and upper thoracic vertebral arches
-insertion point: occipital bone
Neck muscles labelling
Muscles of the back
-superficial group: erector spinae group (spinalis, longissimus, iliocostalis)
-deep group: transversospinalis
Spinalis
-long muscle that sits against the spine
-most medial muscle to the spine
Longissimus
-longer muscle that starts further down
Iliocostalis
-starts at the ilium (pelvis) and attaches to the ribs (costa)
-most lateral muscle to the spine
Back muscles labelling
Transversospinalis
-origin: transverse processes
-insertion: spine
-consist of small slips running up from the spine from transverse processes 3 or 4 levels below
Actions of the muscles of the back
-extend along the entire vertebral column and aid in posture
Dorsal rami of the spinal nerves
-travels into the back (both motor and sensory nerves)
-exit from the intervertebral foramina
Ventral rami
-travels to front of body
-exit through intervertebral foramina
