Spinal Anatomy Flashcards
Osteology
study of the bones/skeleton
Vertebral column in Adult humans
24 vertebrae with a sacrum and coccyx, other bones associated with it are the occipital, temporal bones of skull, 12 pairs of ribs and the sternum
Vertebral column functions
flexible central column, supports head/viscera, suspends upper extremities, body shape, transfers weight, stabilizes body, absorbs forces
Regions of Vert. Column
Cervical - 7 vertebrae, Thoracic - 12 vertebrae, Lumbar - 5 vertebrae, Sacrum - 5 fused vertebrae, Coccyx - 5 fused vertebrae
Curves of the spine
Lordotic - concavity faces posterior
Kyphotic - concavity faces anteriorly, has primary (present at birth) and secondary curves (develop after birth due to musculature and lifting head, sitting walking)
Scoliotic Curve
lateral curve in the coronal plane. Names for the side of the convexity (hump) looking from a posterior view
Names of some abnormal curves
lordosis, kyphosis, scoliosis, straight or military
Functions of the curve
compensate for upright posture of a human, helps absorb forces placed on vert. column, compensate for assymetrical structure and function
Features of Typical Vertebrae
body, vertebral arch containing 2 pedicles, 2 laminae, 7 processes, vertebral foramen, vertebral notches creating the intervertebral canal, pars interarticularis
Zygapophyseal joint
articulation of the Superior Articular facet and the Inferior Articular facet on the SAP and IAP
Occiput
foramen magnum - the spinal cord to brain transition, meninges - dura mater anchored to margin of foramen, vertebral arteries (paired), continuous inferiorly to vertebral canal, external occipital proturberance, jugular and paramastoid proces, mastoid process
3 Part of the Occiput
Basilar, Condylar and Scuamous
Occipital Condyles
lateral to foramen, have articular facets on inferior part for C1 and the tubercles on the medial suface for the alar ligament
Nuchal Lines
on squamous external suface, superior nuchal lines is the insertion of traps, Sternoclavicleomastoid and splenius capitis muscles, inferior nuchal lines is rectus capitis posterior major and minor and obliquus capitis superior, median nuchal line, median nuchal line
Cervical Vertebrae 2 funtional groups
suboccipital (C1 - C2) - providing rotation and flexion and extension of neck, inferior (C3-C7) - allowing for flexion/ext and lateral flex/ext.
Typical Cervical vertebrae
(C3-C6), small flattened body, joint of Luschka - uncinate process and semi-lunar facet, short bifid S.P., articular pillar with IAP and SAP, facet of SAP faces Sup. Post. and Medial., facet of IAP faces Inf. Ant. and Lat., TP are short bifid with an Ant. tubercle - costal, and a Post. tubercle, these create a groove for the spinal nerves, transverse foramen transmit vertebral artery, IVF faces slight ant., slight inf and later.
IVF Border of typical Cervical
IVD, adjacent vert. bodies, joint of Luschka, adjacent pedicles and zygapophyseal joint
Atypical Cervical Vertebrae
Atlas, Axis and C7
Atlas
no body present, ant. and post. arch instead, no spinous process, lare lateral masses where IAP and SAP extend from, widest vertebral neck, anterior arch has ant. tubercle exterior side and fovea dentalis on interal side, post arch has post. tubercle and sulcus for vertebral artery, SA facets are large, elongated and concave, larget vert. foramen
Axis
has odontoid process = dens instead of body, allows for atlas to rotate around on axis, ant. facet of dens articulates with the fovea dentalis, post facet articulates with transverse ligament (cruciate ligament), SA facet is large and face sup., IA facet is oblique like typical cerv. vert., strongest and thickest cervical vertebrae, no uncinate processes but has semi-lunar facet, most deeply bifid SP of spine
C7
transitional vertebrae, SP is long and sloping but not bifid, has one large tubercle on it, vertebral prominens - most easily palpated SP, joint of Luschka exits sup. but not inf. vestigal or absent ant. tubercle, IA facet are like thoracic region facing coronally.
Occipitalization
C1 has partially or completely fused to C0
Atlanto-Occipital ponticulum
narrow bridge or column bone that connects the atlas to the occiput
Carotid tubercle
Ant. tubercle of TP on C6, longest of cervical spine and common carotid artery
Thoracic Vertebrae
Typical (T2-T9), Atypical (T1, T10-T12)
Typical Thoracic Vertebrae
(T2-T9) has body, heart shaped and is thicker dorsally creating kyphotic curve in spine at the region, sup. and inf. costovertebral demi-facets articulate with head of ribs, small circular vert. foramen, SAP extends from pedicle and IAP from the laminae, SA facet is post. in coronal and IA facet is ant. in coronal, TP large and sloped and has costotransverse facets, IVF oriented laterally, inf. notch > sup. notch, rib head is just ant to notch
IVF Border of the Thoracic Vertebrae
sup. and inf. vert. notches, adjacent vert. bodies, IVD, zygapophyseal joint, rid head, demi-facets, adjacent pedicles
Atypical
T1 - mostly resembles T segment, body resembles C vert., has a full costovertebral facet (for 1st rib) and a demi-facet, contributes to vertebral prominens
T10- demi-facets for 10th ribs superior but none for 11th
T11- large body and lumbar like, not heart shaped, complete CV facet for 11th rib, no costotransverse facet, SP is short and rectangular
T12- same as T11 except IA facet faces laterally like lumbar, TP has 3 processes - Mamillay, Accesory Mamillary, and Lateral
Lumbar Vertebrae
Typical (L1-L4) and Atypical (L5)
Typical Lumber Vertebrae
largest moveable segments, large body in shape of kidney, vert. foramen is intermediate & triangular shaped, SP stout and rectangular (common site of spina bifida), facets of AP are in sagittal orientation, mamiallry process and accessory mamillary process, TP is long and slondor and points horizontal, largest IVF with larger Inf. notch than Sup., lateral recess!
Atypical Lumbar Vertebrae
IA facets face anterior and lateral, body shortest and widest of all lumbars, small SP, common site for spondyloschisis, spondylolysis, spondylosynthesis
spondyloschisis
fissure, cleft or split of the SP also known as spina bifida
spondyloschisis
to dissolve or break apart at pars interarticularis
spondylolysis
splitting/displacement of vertebrae from it normal alignment
lumbarization
anomoly where the S1 if the sacrum does not fuse and remains another lumbar like vertebrae
sacralization
anomoly where L5 or C1 are fused to the sacrum usually seen by having another dorsal and ventral foramen in the sacrum
tropism
assymetry of facet planes within a segment
causa equina
after the spinal nerve ends at L1 or L2 it turns into a multiple of many spinal nerve wrapped into one
IVF Border of the Lumber Vertebrae
adjacent vert. bodies, IVD, pedicles, Vert. notches, Zygapophyseal joint and IAP and SAP
Sacrum descriptors
linked with pelvic girdle via sacro-iliac joint, 5 fused segments forming wedge-shaped structures, specialized for transfer of weight and body through pelvis, concave anteriorly, from roof of pelvic cavity
Sacrum Osteology
base, apex, sacral canal, sacral hiatus, sacral cornu, transverse lines, dorsal and ventral foramen, median intermediate and lateral sacral crests, pars lateralis, auricular surface, sacral tuberosity, SAP at base with facets facing post., promontory
Coccyx
3-5 fused vertebrae, apex, base, cornu
caudal vertebrae, no pedicles laminae vert. canal or SP TP AP IVF.
Sternum
formed by 6 sternae segments, 3 parts in adult: manubrium, body and xiphoid process
manubrium
jugular and suprasternal notch
articultes with clavicle, 1st costal sartilage, corpus sterni
manubriosternal joint which has an of setting angle in it posteriorly refered to as the angle of louis
Body
four fused sterna
articulates with 2nd - 7th costal cartilage
xiphisternal joint
Xiphoid Process
siwth sternae
ossifies in some, others cartilaginous throughout life
articulates with 7th rib
trauma and hepatic laceration
Ribs
True Ribs, False ribs, Floating ribs
Typical Ribs
R2-R10
head - vertebral end, sup. and inf. facets divided by interarticular crest, these facets articulate with demi-facets (rib Tn)
neck - short,
tubercle - is at junction of neck and shaft, articular facet to TP,
shaft - has costal angle, rounded superior edge and sharply angled inferiorly, costal groove
distal end articulate with costocartilage (costochondral articulation)
costocartilage joints articulate with the sternum to form a sternocostal joint
Atypical Rib
1,11,12
Supranumerary Ribs
adding of an extra rib to C7 of L1
Classification of Joint Based on movement
Synarthrosis, Amphiarthrosis, Diarthrosis
Synarthrosis
these joints permit little, if any, movement
bony edges are very close together and may even interlock
Amphairthrosis
joint that permits slight movement, bones are usually farther apart then they are at a synarthrosis
Diarthrosis
these joints permit a wide range of motion, freely moveable
Classifications of joint based on CT
Fibrous
Cartilaginous
Synovial
Cartilaginous
articulating surface connected with cartilage
Fibrous
articulating surfaces are connected by fibrous CT
Synovial
articulating surfaces covered by articular cartilage, surfaces are separated by a joint capsule or synovial cavity and held together by a fibrous joint capsule and extra-joint capsular ligaments
Two Major joints of the Vertebrae
Cartilaginous Joints
Central Joint - Intervertebral Joint, jt. b/w the vertebral bodies and are unpaired, includes the IVD that is fibrous tissue, limited movement in relation to size of joint
Synovial
Zygapophyseal joint - b/w SAP and IAP of adjacent segments, joint complex includes a fibrous capsule lined by synovial membrane and filled with synovial fluid, greater movement in relation to size, gliding movement
Central Joint
-atypical or absent b/w occiput and C1, C1 and C2, sacral segments, and most coccygeal segments
-IVD usually described as a fibrocartilaginous complex that helps the central joint of the spine
-Anterior Longitudinal Ligament
-Posterior Longitudinal Ligament
-
IVD
- classified as ligament b/c it binds to adjacent vertebral bodies
- 23 discs, 1/4 length of spine, largest in lumbar, thicker anteriorly in lumbar and cervical causing lordotic curve
- 3 parts:anulus fibrosis, nuclues pulposus, vertebral end plates
- IVD adheres to: peripheral small rim on upper and lower surfaces of adjacent vertebral bodies, rib head in thoracic
- functions of IVD: abrsorbs forces, contributes to lumbar and cervical curves, binds and limits motion, resists types of forces
- innervation and blood supply: just the outer anulus pulpous supplied sparsely by branches of spinal arteries, the same part is innervated by 1. ventral rami of spinal nerve 2.sympathtic trunk
- IVD is subject to degenerative changes and injury protrusion and herniation usually posterior lateral.
Schmor’s Node
condition where nucleus pulposus is displaced or ruptures a vertebral end plate into adjacent vertebral body
paresis
weakness of muscle; partial paralysis of muscle
paralysis
total loss of control of a muscle
paresthesia
abnormal sensations, tingling itching burning pins and needles.
ALL
attaches to anterior surface of vertebral bodies and IVD’s from axis to sacrum
become wider as you descend
thickest in thoracic to help kyphotic curve
thicker adjacent to bodies than discs
layered adding strength and integrity
resists extension of back
PLL
attaches to posterior surface of vertebral bodies and Ivd;s from axis to sacrum-positioned on post canal wall
wider cranially,thicker in cervical and lumbar regions to help lordotic curve
thickest along midline, thins laterally
layered for strength and integrity
resists flexion of spine
Zygapophyseal Joints
synovial - gliding joint
articular surfaces are covered with 1mm thick of hyaline cartilage
joint capsule = articular capsular ligament
-thin and lax providing little resistance to movement, has extracapsular ligaments to control motion, synovial meniscoids
innervation by branches of dorsal primary rami of spinal nerves
contributes to posterior wall of I.V.F.
Synovial Meniscoids
projections from the inner surface of the joint capsule into the joint space; folds include adipose tissue, vessels and nerve endings covered by synovial membrane
Ligamentum Flavum
attaches laminae to adjacent vertebrae, extends from C2 to sacrum
thick, tough, yellow b/c of elastic fibbers, contributes to the medial part of Zy Jt.
helps form post wall of vertebral column
resists flexion and absorbs forces
helps posterior muscles maintain erect position
Supraspinous LIgament
attaches tips of spinous processes extending from C7 to sacrum
above C7 it becomes the funicular part of nuchal ligament in neck
resists flexion of spine
Interspinous LIgament
between spinous processes resists flexion (poorly developed except for lumbar)
Intertransverse Ligament
b/w TP’s
resists lateral flexion and rotation
Nuchal Ligament
two part fibrous septum in posterior neck
-funicular part; post part attaches from SP of C7 to EOP
-lamellar part:anterior part SP of cervical to median nuchal line
provides support to head/neck and serves as muscle attachment
innervated mainly by dorsal rami C2-4, for proprioception and pain, may be implicated in cephalgia
Uncostovertebral Joint
b/w uncinate processes and semi-lunar facet, often described as a synovial joint bounded by articular capsule
limits lateral flexion and rotation
Atlanto-occipital Articulation
diarthrosis; convex occipital condyles articulate with concave superior facets of atlas
mainly hinge like flexion and extension
Ligaments that attach: articular capsule, anterior A-O ligament, posterior A-O ligament, lateral A-O ligament, posterior and lateral ponticulum
Anterior Atlanto-Occipital Ligament
b/w anterior arch of C1 and anterior margin of foramen magnum
Posterior Atlanto-Occipital Ligament
homologue to ligamentum flavum b/w posterior arch of atlas and posterior border of foramen magnum
Lateral Atlanto-Occipital Ligament
strengthens articular capsule laterally, attaches lateral mass of the atlas to the paramastoid process of jugular process of occiput
Posterior Ponticulum
ossification of posterior atlanto-occipital membrane
Lateral Ponticulum
ossification of lateral atlanto-occipital membrane
Atlanto-Axial Articulation
complex of three joints: two gliding IAPs of C1 and SAPs of C2, these joints are sometimes called the lateral atlanto-occipital joints, the articular facets are large, oval and closest to the horizontal plane
median atlantoaxial joint, pivot trochoid b/w odotoid process and the fovea dental is
Mainly pivot motion but also some lateral flexion and flex/ext
Ligaments: articular capsule, anterior atlato-axial ligament, posterior atlanto-axial ligament, transverse ligament and accessory ligament
Anterior Atlanto-axial Ligament
b/w body of axis and the anterior arch of atlas, homologue to ALL
Posterior Atlanto-axial LIgament
b/w the posterior arch of atlas and laminae of axis, provide spring like resistance to flexion
Accessory ligament
attached lateral mass of atlas to posterior body of the axis; inside the vertebral canal deep to techtorial membrane; limits lateral flexion and excessive rotation b/w atlas and axis
Occipito-Axial Complex
Not a direct articulation
Involves ligament; unites atlas, axis and occiput into a coplex
Tectorial membrane, crusiform ligament, alar ligament, apical ligament (apical dental)
Tectorial Membrane
continuation of posterior longitudinal ligament; attaches to posterior body of axis and the anterior border of foramen magnum where it also blends with cranial dura mater
strengthens the cruciate/crusiform ligament and medial part of the atlanto-axial and atlantoccipital joint capsules
Crusiform Ligament
deep to techtorial membrane
holds dens against posterior facet of anterior arch of atlas yet permits rotation
2 parts: longitudinal part- superior band (ant border to FM) and an inferior band (post part to C2 body)
transverse part- attaches the L and R lateral masses of atlas, articulates with post. facet on the dens
Alar Ligament
attach dens to the medial aspect of each occipital condyles
limit amount of rotation b/w head and axis
Apical Ligament
attaches dens to anterior border of FM
small rudiment of an IVD.
Suboccipital Nerve
C1 spinal nerve that innervates the suboccipital muscles
Greater Occipital Nerve
branch of C2 spinal nerve that has cutaneous distribution to back of head
5 Joints that effect the Thoracic Spine
central joint - IVD’s, thin and small
zygapophaseal joint -synovial, in coronal plane
costovertebral joint - gliding synovial joint b/w rib head and demi facets
costotransverse joint - gliding synovial joint b/w rib tubercle facet and CT facet
costochondral joint and sternocostal joint - both are synchondrosis cartilagenous joints
Ligaments of Costovertebral Joint
costovertebral capsular ligament
interosseous costovertebral ligament
radiate costovertebral ligament
Ligaments of Costotransverse Joint
costotransverse articular capsule
interosseous costotransverse ligament
lateral costotransverse ligament
superior costotransverse ligament
Articulations of Lumbar Spine
Zygapophaseal Joint - sagittal plane Ligaments with the lumbar spine Intervertebral Discs Iliolumbar ligaments Ligaments binding L5 to sacrum Transforaminal Ligaments
Ligaments of the Lumbar spine
ligamentum flavum, supraspinous, interspinous, intertransverse, anterior longitudinal, porterior longitudinal, articular capsular ligaments,
IVD of Lumbar Spine
are kidney shaped, large and think and designed for a greater weight carrying capacity
Iliolumbar ligament
two bands:
superior that goes from TP of L4 to iliac crest
inferior the goes from TP of L5 to iliac crest
provides support to L4 and L5 during flex-ext and lateral flexion
Ligaments binding L5 to sacrum
anterior longitudinal ligament
posterior longitudinal ligament
lumbosacral capsular ligament
supraspinous and interspinous ligaments that extends from L5 to Smedian creat
ligamentuum flavum
lumbosacral ligament - from L5 TP to sacral ala
IVD of L5
Transforaminal Ligaments
think CT that traverse the area of the IVD, variable in size, attachments and level of appearance
Sacroiliac Joint
b/w articular surfaces of ilium and sacrum Sacral Articular surface -on lateral surface of S1-S3 segments -lined by hyaline cartilage -groove fits with ridge of ilium Ilium Articular Surface -ridge, guides sacroiliac motion -lined by fibrocartilage S.I. joint now well developed at birth, become synovial and can become fibrous common sites of injury and pain
Ligaments of the sacroiliac joint
Sacroiliac articular capsule
posterior articular ligament - strong and extensive, long and short parts, orevents sacrum from falling
anterior sacroiliac ligament - thin, much less significant, blends with the articular capsule
interosseous sacroiliac ligament - short, very strong, attaches sacral and ilial turberosities
Has 2 accessory ligaments:
sacroturberous ligament - strong, long and short parts, attaches to ischial tuberosity
sacrospinous ligament - short, strong, and attaches to ischial spine
