Spine Flashcards
Spine function
- support head and trunk
- ligament, muscle and bone attachment
- protect spinal cord and internal organs
- allow trunk mobility
- shock absorption
- link between UE and LE
What makes up the upper cervical spine
Occipital-atlanto (O-C1) and Atlanta-axial (C1-C2)
What makes lower cervical spine
C2-C7 (inferior articular facets of the C2)
Occipital-Atlantal joint
AO joint
-occipital condyles (convex) with concave lateral masses of atlas
-synovial joint (no disc)
Occipital-Atlantal Joint ROM (osteokinematics)
flexion: 5º
extension: 10º
Lateral bending: 5º
rotation 0º
Occipital-Atlantal Joint arthrokinematcis
Convex on concave
-roll and glide: opposite direction
-flexion: anterior roll and posterior glide
-extension: posterior roll and anterior glide
-lateral Bending: ipsilateral roll and Contralateral glide
Atlanta-axial joint
- articular processes
- ligament
-articular processes are in the transverse plane
-alar ligament prevent excessive rotation
Atlanta-axial joint ROM
- Flexion: 5º
- Extension: 10º
- lateral bending 0º
- rotation 40-45º
Lower Cervical vertebrae description
- smaller/narrow vertebral bodies (does not hold a lot of weight)
- narrow disc
-C2-C7
Lower cervical vertebrae facet orientation
45º to the transverse plane with the posterior portion being more inferior
Lower cervical Osteokinematics + ROM
Flexion: 35º (7 per segment)
Extension: 70º (12-14 per segment)
Lateral bending 35º (7º per segment)
Rotation: 45º (9 per segment)
Arthrokinematics in cervical flexion and extension
Flexion:
- anterior tilt
- facet glides superiorly
- anterior shear
Extension:
- posterior tilt
- facet glides inferiorly
- posterior shear
Arthrokinematics in cervical lateral flexion
-IL tilt
-IL downward glide
-CL upward glide
-some rotation
Arthrokinematics in cervical rotation
-cannot purely get translation
-when you rotate you get some side bending
- posterior slide on IL side
- anterior slide on CL side
- rotation indirection of the rotation
Cervical spine coupled motion
-lateral bending and rotation to the same side
Thoracic spine function
- rib articulations and rib cage to protect organs and assist with respiration
Body of the thoracic vertebrae+ SP, Facets
-bigger body
-SP is angled down (SP of T7 is in line with body of T8 and so on)
- demi facets (1/2 is on vertebrae above and one on the vertebrae below) that articulate with head of the ribs
Segmental differences of rib motions
-upper thoracic ribs: elevates anterior and moves like a pump handle
-lower thoracic ribs: lower raise laterally
Thoracic spine articular processes orientation
-60º to transverse plane
-20º to frontal plane
Thoracic Spine ROM
Flexion: 30-40º (3º per segment ribs limit motion)
extension: 20-25º (2 per segment)
lateral bending: 25º (2 per segment)
rotation: 30º (3º per segment)
Thoracic spine coupled motions of the upper/lower thoracic
-upper thoracic: behave more like cervical
-lower thoracic behave more like lumbar
Typical lumber vertebrae
larger and wider vertebral bodies/disc
lumber spine facet orientation
90º to transverse plane
45º to frontal plane
-encourage flexion/extension
-discourage rotation
Lumbar spine ROM
flexion: 50º (10/segment)
extension: 15º (3/segment)
lateral bending: 20º (4/segment)
rotation: 5º (1/segment)
Thoracolumber motion
More motion in flexion
-more extension in cervical
Lumbar spine coupled motion with lateral bending and rotation
lateral bending and rotation to the opposite side
Functional units of the spine
-upper cervical: occiput C1, C2
-lower cevical: C2-T3
-Thoracic: T3-T9 or T10
-low back: T10-S1
Spinal curves - primary and secondary
Primary: present at birth = kyphosis (whole spine)
secondary: develops as we being to challenge gravity (lordosis)
-gain control of head = cervical lordosis
-lumbar lordosis = develop when sitting and standing
Explain how the spine is a closed system
-changing 1 area will influence another such as while sitting if you increase lordosis you will sit up straighter and bring yourself to better posture
-motion in one segment influences another
intervertebral disc (IVD)
- functions
- where are they located
-size
-forces
-shock absorber
-C2 and lower
-account for 20-30% of length of vertebral column
-increase in size C-L (3mm-9mm)
-resist tensile and shearing forces
-distribute compressive forces
IVD structure:
-cartilaginous end plate
-annulus fibrosus
-nucleus pulpous
-lamella
forces it resist
-cartilaginous end plate: vertebral body is connected to Articular cartilage and get nutrients from there
-Annulus fibrosus: outter portions are made of rings that attach to both vertebral bodies; has more type 1 for thick collagen to resist tensile, shearing and compressive forces
-nucleus pulpous: type 2 more water for shock absorber
-lamella=layers of the annulus fibrous cross to resist in one direction (rotation)
-together resist tensile
-contain nucleus
Movements of vertebral bodies in each plane
-translation in the frontal plane
-compression/distraction in vertical plan (axial)
-anterior/posterior translation in sagittal plane
-side to side rotation tilting in frontal plane
-rotation in transverse plane
-anterior/posterior rotation (tilting) - more rotation when being and small amounts when standing
IVD function in response to forces and nucleus migration
-posterior/flexion: compression anteriorly + distraction posteriorly
-anterior/extension: compression posteriorly + anteriorly
-opposite/lateral flexion: compression IL and distraction CL
What is the relationship between the IVD and loads (spine)
the discs play a role in mobility and stability
-the spine and discs allow for great mobility during light or no loads
- the spine and discs allow for great stability during heavy loads
- during a compressive force, the nucleus pushes out and the annulus contains it giving the disc stability
What is a herniated/protrusion nucleus pulposus
when there is a protrusion of the nucleus pulpous into the annulus fibrosus
What is a prolasped/extrusion of the nucleus pulposus
when the nucleus pulpous breaks through the annulus fibrosus
What is a sequestration of the nucleus puplosus
the parts of the that are free outside the disc
What is the classification and role of the facet (zygoapophyseal) joints?
-diarthrodial synovial joint
- role is to guid, limit, and control motion as well as to protect discs from shearing forces
Anterior longitudinal ligament
Vertebral body to vertebral body on the anterior surface
-limits extension
Posterior longitudinal ligament
vertebral body to vertebral body posteriorly
-limits flexion
Ligamentum flavum (yellow ligament)
lamina to lamina
-limits flexion
interspinous
between the spinous processes
-limits flexion
intertransversalis
between the transverse processes
-limits lateral flexion
Supraspinous
runs the length of the spinal column above the spinous process
-limits flexion
additional spinal support besides ligaments
-facet joint capsule: limits flexion/extension by limiting superior/inferior glide
-muscle: dynamic stability
-thoracolumbar fascia: stability
The abdomen is a closed loop and has hoop stress
Describe hoop stress`
the abs provide hope stress through the thoracolumbar fascia to help support the spine
what is the sacrohorizontal/lumbosacral angle
-S1 slops anterior and inferior (40º)
-sacral facets are directed posteriorly
- the facet joints are a bony block that keep L5 from sliding forward
-the isthmus is a tiny bone that keeps it from sliding forward
- spondyolysis
- spondylolysthesis
- a fracture: isthmus breaks and L5 wants to slide forward
- slippage L5 slides forward
Describe the anatomy of the SI joint
Sacroiliac joint
- articulation at S1 to S3 levels
- C shaped articular surface
- synovial then modified synarthrosis (the pelvis is lined with fibrocartilage but the sacrum is lined with articular cartilage
-as we age the surfaces become less smooth making little ridges that help lock the joint in place
- minimal movement due to strong ligamentous support
SI ligaments
- sacroiliac (anterior/posterior): sacrum to ilium
- Interosseous: between the bones (intimate with the joint)
- sacrospinous: sacrum to iliac spine
- sacrotuberous: sacrum to ischial tuberosity
SI forces
- gravity: pushes torso downward and wedges the scrum into pelvis making a closed ring
- ground reaction: ground pushes up through the legs
Pubic symphysis joint
-functions with SI joint (forms a closed ring)
-synarthrosis
-fibrocartilage disc
Pubic symphysis ligaments/support
superior, inferior and posterior
-anterior muscular support
What happens during spinal flexion to
1. vertebral bodies
2. Articular processes
3. disc
4. spinous process
5. IV foramen
6. limits to motion
- vertebral bodies: tilt anterior (cervical has some shearing)
- Articular processes: superior glide
- disc: anterior = compression posterior = distraction and the nucleus is pushed posterior
- spinous process: ligaments are taut
- IV foramen: increases in size
- limits to motion: interspinous ligament, posterior longitudinal ligament, ligamentum flava, nuchal ligament
Spinal stenosis
caused by degeneration of IVD or a build of Boone around the IV foramen
-narrowing the area where the nerve comes out
-flexion will alleviate symptoms
Spinal extension
1. vertebral bodies
2. facets
3. disc
4. spinous process
5. IV foramen
6. limits to motion
- vertebral bodies: tilt posterior
- facets: glide inferior
- disc: anterior = distraction, posterior = compression and nucleus gets pushed anteriorly
- spinous process: relaxed
- IV foramen: narrows
- limits to motion: anterior longitudinal ligament
Spinal lateral bending on the concavity side
1. vertebral bodies
2. facets
3. disc
4. IV foramen
5. limits to motion
- vertebral bodies: Tilt toward
- facets: inferior glide
- disc: compression
- IV foramen: narrows
- limits to motion: joint capsule, inter transversealis on other side
Spinal lateral bending- convexity
1. vertebral bodies/disc
2. facets
3. IV foramen
4. limits to motion
- tension (also tension on annuleus)
- facet glides superiorly
- foramen opens on the side
- limiting structures: intertransveralis
describe the sacral motions
- flexion/nutation: the base (top of the sacrum that articulates with L5) moves anteriorly
- pelvic brim (top opening) reduced
- pelvic outlet (bottom opening) increased - extension or couternutation: base moves posteriorly
- pelvic brim increases
- pelvic outlet decreases
What are the force couples of pelvic tilti
- lumbar extensors and hip flexors produce an anterior pelvic tilt with lumbar extension
-abdominal muscles with the hip extensors produce a posterior pelvic tilt with lumbar flexion
Lumbopelvic rhythm
for every 4 of thoracolumbar motion there are 3 degrees of hip motion
