KP221- Final Exam

The Vertebral Column

Also known as the spine or the spinal column

How many vertebrae in the vertebral column?

33 vertebrae

Movements of the Vertebral Column

Flexion, Extension, Lateral Flexion, Rotation

Fetal Spinal Curvature

Vertebral column is C-shaped

Newborn Spinal Curvature

Slight flexes present between lumbar and sacral areas

Adult Spinal Curvature

Thoracic & Sacral curvatures represent the remains of the original curve

Typical Vertebra Body

Cylindrical & heavy made of spongy bone and covered by thin layer of cortical bone

Vertebral Pedicles

2, on posterior side, extend posteriorly & connect to laminae

What makes up the vertebral arch?

Vertebral foramen & Vertebral canal

Vertebral Foramen

Between vertebral arch & body

Vertebral Canal

Successive vertebral foramina, where spinal cord lies

Transverse process of vertebra

Project laterally at point of union of pedicle & laminae

Function of Transverse Process

Allow for muscle attachment & articulation with ribs

Zygapophyses(Z joints)

Junction of pedicle & lamina

Function of Z joints

Facets for articulation with vertebrae above & below

Spinous Process

Midline posterior projection from laminae

Function of Spinous process

Allow for attachment of muscles

Cervical Vertebrae

Get increasingly larger caudally, C7 transition between cervical & thoracic vertebrae, C1-C7

Atlas(C-1)

-Superior articular facets are concave & articulate with occipital consults of skull
-Inferior articular faces are flatter & articulate with axis

Axis(C-2)

-Dens articulate with anterior arch of atlas & held in position by ligament
-Dens act like a pivot around which the atlas rotates

Thoracic Vertebrae

Superior & inferior articular facets almost in frontal plane, no foramina, costal facets articulate with ribs, spinous processes are long, slender, directed downward & overlap each other, T1-T12

Lumbar Vertebrae

Bodies massive, spinous processes much heavier & broader, height of lamina is less than body, transverse processes are long & slander, L1-L5

Sacrum

The large, triangle-shaped bone in the lower spine that forms part of the pelvis , made of 5 fused bones of the spine

Pelvis Sacral Foramina

Ventral rami of S1-S4 exit

Transverse Process of Coccyx

Articulate with hip

Median Crest of Sacrum

Rudimentary spinous processes

Dorsal Sacral Foramina

Dorsal rami of S1-S4

Coccyx

3 or 4, 1st is usually separate from rest, tailbone

Sacral Canal

continuation of vertebral canal

Sacral Hiatus

the opening into the spinal canal in the midline of the dorsal surface of the sacrum between the laminae of the fifth sacral vertebra

Intervertebral Discs

fibrocartilage pads that separate and cushion the vertebrae, most superior between C2 & C3, most inferior between L5 & S1, composed of annulus fibrosis and surround nucleus pulposis

Annulus Fibrosis

outer layer of intervertebral disc, inserts into smooth, rounded rims on articular surface of vertebral bodies

Nucleus Pulposus

inner gelatinous nucleus, gives disc its elasticity and compressibility

Anterior longtitudinal ligament(ALL)

strong fibrous band which covers & connects anterior aspects of vertebral bodies & intervertebral discs, stretches from sacrum to C1 & occipital bone

Function of ALL

maintains stability of joints between vertebral bodies & prevents hyperextension of spine

Posterior longitudinal ligament(PLL)

narrower & weaker than ALL, runs along posterior aspect of vertebral bodies within vertebral canal

Function of PLL

prevents hyper flexion of spine & posterior protrusion of nucleus pulposus of disc

Ligamenta flava

connect laminae of adjacent vertebrae

Interspinous ligament

connects the spinous processes of adjacent vertebrae(weak)

Supraspinous ligament

connects tips of spinous processes (C7 to sacrum)

Ligamentum nuchae

superior aspect of ligaments, triangular median septum between muscles on each side of posterior aspect of neck

Intertransverse ligaments

connects adjacent transverse processes

Atlanto-occipital joint

permits nodding of head(between skull & C1)

Atlanto-axial joint

permits rotation of head(skull & C1 rotate about C2)

Transverse ligaments of axis

holds dens against anterior arch of atlas

Cruciform ligament

transverse ligament of atlas and vertical ligament from skull; holds body of C2 and dens to the inside of the skull

Altar ligament

extends from side dens to lateral margins of foramen magnum, rotation and side to side movements

Tectorial membrane

superior continuation of posterior longitudinal ligament, extends from body of atlas to occipital bone

Thoracic & Abdominopelvic Cavities

ventral body cavity

Muscles of Abdominal Wall

5 paired muscles in anteriolateral wall:
3 flat: form layers
-external oblique, internal oblique, transverse abdominis
2 vertical: contained within texture sheath
-rectus abdominis, pyramidalis

Aponeuroses

fibrous or membranous sheet connecting a muscle and the part it moves

External Oblique

largest and most superficial layer

Origin of external oblique

external surface of 5-12th ribs

Insertion of external oblique

linea alba, pubic tubercle, iliac crest

Action of external oblique

assists in torsional rotation of trunk

Internal Oblique

tenses abdominal wall and compresses abdominal contents

Origin of internal oblique

thoracolumbar fascia, anterior 2/3 of iliac crest, connective tissue lateral 2/3 of inguinal ligament

Insertion of internal oblique

inferior border of 10-22 ribs, linea alba, & pectin pubis

Action of internal oblique

compress and support abdominal viscera, flex and rotate trunk

Transverse abdominis

compresses abdomen & increases intra-abdominal pressure

Origin of transverse abdominis

internal costal cartilage ribs 7-12, thoracolumbar fascia, iliac crest, lateral 1/3 inguinal ligament deep connective tissues

Insertion of transverse abdominis

linea alba & internal oblique aponeurosis, pubic crest & pectin pubis

Rectus abdominis

flexes and rotates vertebral column

Origin of rectus abdominis

pubic symphysis & pubic crest

Insertion of rectus abdominis

xiphoid process and costal cartilages of ribs 5-7

Action of rectus abdominis

flexes trunk(lumbar) & compress abdominal viscera; stabilizes & controls pelvic tilt

Pyramidalis

small triangular muscle of the lower front part of the abdomen that is situated in front of and in the same sheath with the rectus and functions to tense the linea alba

Origin of pyramidalis

anterior surface of pubis & anterior pubic ligament

Insertion of pyramidalis

linea alba

Action of pyramidalis

tenses linea alba

Serratus Posterior Superior

extend obliquely from the vertebral column to the rib cage

Origin of serratus posterior superior

lower part of ligamentum nuchae, spinous processes of C7-T2/3

Insertion of serratus posterior superior

2nd-5th ribs

Nerve Innervation of serratus posterior superior

first 3 or 4 intercostal nerves(ventral ram of spinal nerves)

Action of serratus posterior superior

assists in elevating ribs

Serratus Posterior Inferior

an extrinsic muscle of the back and is found in the lower back region

Origin of serratus posterior inferior

T1-L2 of spinous processes

Insertion of serratus posterior inferior

9th-12th ribs

Nerve innervation of serratus anterior inferior

9th-12th intercostal nerves

Action of serratus anterior inferior

draw lower ribs downward to enlarge thoracic cavity & stabilize ribs against pull of diaphragm

Splenius Capitis

rotates head, bends head to one side, or extends neck

Origin of splenius capitis

lower half of ligamentum nuchae & spinous process of C7 & T1-T3/4

Insertion of splenius capitis

mastoid process & occipital bone

Splenius Cervicis

a paired back muscle found in the prevertebral space of the neck

Origin of splenius cervicis

spinous process of T3-T6

Insertion of splenius cervicis

transverse processes of C1 & C2-C4

Nerve Innervation of splenius cervicis

both are innervated by dorsal rami of middle & inferior cervical spinal nerves

Action of splenius cervicis

unilateral: rotate head & cervical spine toward same side
bilateral: assist in extension of head & neck

Erector Spinae

large mass of muscle with origin over the upper sacral & lower lumbar vertebrae

Insertion of erector spinae

medial crest of sacrum

Origin of erector spinae

posterior surface of sacrum, iliac crest & solid processes of T11-L5

Nerve innervation of erector spinae

dorsal rami of spinal nerves

Action of erector spinae

extends thoracic vertebral column

Iliocostalis lumborum

Origin of Iliocostalis lumborum

iliac crest & sacrum

Insertion of Iliocostalis lumborum

slips into lower 6/7 ribs

Iliocostalis cervicis

Origin of Iliocostalis cervicis

angles or upper 6 ribs(medial to iliocostalis thoracic insertion)

Insertion of Iliocostalis cervicis

transverse processes of C4-C6

Iliocostalis thoracis