Exam #3 - Lumbar Spine Flashcards
The vertebral column consits of how many vertebral bony segments?
33
Normal Curvatures
- Define the ____ position of different regions
- Considered ____
- Define the neutral position of different regions
- Considered dynamic
Cervical & lumbar curves develope with ____ maturation & assuming a more ____ posture
Cervical & lumbar curves develope with motor maturation & assuming a more upright posture
Anatomical factors influencing the curves of the spine (4)
- Wedge-shaped intervertebral discs or vertebral bodies
- Spatial orientation of apophyseal joints
- Tension in ligaments
- Degree of natural muscle stiffness
Line of gravity (ideal posture)
- Passes near the ____ ____
- Anterior to the 2nd ____ ____
- Posterior to the ____
- Anterior to the ____
- Anterior to the ____
- Passes near the mastoid process
- Anterior to the 2nd sacral vertebra
- Posterior to the hip
- Anterior to the knee
- Anterior to the ankle
The line of gravity (ideal posture) promotes ____ shape of spinal curves
promotes optimal shape of spinal curves
These factors affect what?
- Fat deposition
- Specific shapes of regional spinal curvatures
- Static posture of the head & limbs
- Muscle strength
- Connective tissue extensibility
- Position & magnitude of loads supported by the body
Spatial Relationships of vertebrae
The lumbar vertebrae increases in size from ____ to ____ in order to accomidate progressively ____ loads
The lumbar vertebrae increases in size from L1 to L5 in order to accomindate progressively increasing loads
Lateral recess is located medial to the
Intervertebral foramen
What structures makeup the neural arch?
- 2 pedicles
- 2 laminae
- 2 superior articular processes
- 2 inferior articular processes
- 2 transverse processes
- 1 spinous process
Three functional components of the Intervertebral Junctions
- Transverse & spinous processes
- Apophyseal joints
- Interbody joint
Function of Interbody Joints
- Transmit forces from ____ & ____ to cranial
- Promotes ____ & ____ throughout the vertebral column
- Transmits forces from cranial & caudal to cranial
- Promotes stabilization & mobility throughout the vertebral column
Interbody Joints
- 23 interbody joints
- From ____ to ____
- Classified as a ____
- Consists of an intervertebral disc, vertebral endplate & adjacent vertebral bodies
- 23 interbody joints
- From C2-3 to L5-S1
- Classified as a cartilaginous
- Consists of an intervertebral disc, vertebral endplate & adjacent vertebral bodies
The state of leaning, resting or reclining
recumbency
Is the IV disc taller or shorter in the morning?
Taller
The combined heights of the intervertebral disc accounts for ~____ - ____% of the total length of the spinal column
~20-33%
- Diurnal (daily) changes occur within the disc
- Sustained compression removes fluid from disc (dehydrates)
- Unloading the disc (recumbency) results in imbition of fluid
- 2cm taller in the morning
Intervertebral Discs
- Pulplike gel located in the mid-to-posterior part of the disc
- 70-90% water
- 15-20% type II collagen
- Thickened into gel-like consistency via proteoglycans
Nucleus Pulposus
Function of Nucleus Pulposus
- Allows the disc to act as a modified ____ ____
Hydraulic shock
- Encases the nucleus pulposus
- Type 1 & Type 2 collagen make up 50-60% of the dry weight
- Elastic protein
Annulus Fibrosus of intervertebral disc
Function of Annulus Fibrosus
- Constrain the nuclear material during ____ loading thereby promoting an ____ hydrostatic pressure
Constrain the nuclear material during compressive loading thereby promoting an increased hydrostatic pressure
Function of End Plate
- Adhere the discs to the vertebral bodies & promote ____ of nutrients to the intervertebral disc
Adhere the discs to the vertebral bodies & promote diffusion of nutrients to the intervertebral disc
Intervertebral Disc: End Plate
- Thin cartilaginous caps that cover most the ____ & ____ surfaces of the vertebral bodies
- Disc surface is ____
- Vertebral surface is ____ cartilage (weak link)
- Thin cartilaginous caps that cover most the superior & inferior surfaces of the vertebral bodies
- Disc surface is fibrocartilage
- Vertebral surface is calcified cartilage (weak link)
Intervertebral Disc: Axial Loading
When a load is applied vertically
* Nuclear pressure ____
* The nucleus ____ & ____ the compressive forces
- Nuclear pressure rises
- The nucleus absorbs & transmits the compressive forces
During axial loading the nucleus absorbs & transmits the compressive forces to…
Vertebral end plates & annulus fibrosus
Axial Loading
Peripheral pressure ____ the tension on the collagen fibers, which resis it until a ____ is reached
Peripheral pressure increases the tension on the collagen fibers, which resis it until a balance is reached
Axial Loading
The point when radial pressure is matched by the collagen tension
* Pressure is transfered from one end plate to another
* Nucleus pulposus braces the annulus fibrous preventing buckling under sustained loads
Peripheral pressure of the intervertebral disc is balanced
The nucleus pulposus is ____ but relatively incompressible
Deformable
The extent & magnitude of compression of the intervertebral disc depends on what 3 components
- Amount of applied compressive force
- Disc height
- Cross-sectional area of the disc
Primary factors that affect intervertebral disc height variations
Related to intrinsic individual factors such as (5)
- body height
- gender
- age
- disc level
- geographic region
Secondary factors that affect intervertebral disc height variations
Associated with extrinsic factors such as (3)
- degeneration
- abnormality
- clinical management
Intradiscal Pressure Studies
Disc pressures are large when holding a load in
front of the body especially when bending forward
Intradiscal Pressure Studies
Sitting in a forward-slouched position proceduces ____ disc pressure than sitting erect
greater disc pressure
Intradiscal Pressure Studies
Lifting a load with knee flexed places ____ pressure on the lumbar disc than does lifting a load with the knees straight
less pressure
Intervertebral Disc: Torsion
Segmental rotation of 3° or greater could
Promote injury
Intervertebral Disc: Torsion
What increases the potential for a lateral shear on the annulus & tension at the contralateral ZAJ
The superior vertebrae pivot backwards on impacted joint causing vertebrae to swing laterally & backward
Intervertebral Disc: Torsion potential results
- Compression fx of ____ ____
- Subchondral fx
- Fragmentation of the articular surface & ____
- Avulsion of the ____ joint capsule
- Pars interarticularis fx
Compression fx of the contralateral lamina
Fragmentation of the articular surface & tearing
- 24 pairs throughout the spine
- Formed between opposing articular facet surfaces
- Planar joint
Apophyseal joints
Apophyseal Joint Function: Permit certain movements & block other movements
- Horizontal facets promote ____ ____
- Vertical facets ____ axial rotation
- Horizontal facets promote axial rotation
- Vertical facets block axial rotation
L1 to L4 region forms what function
Thoracolumbar junction
L5 to S1 region forms what function
Lumbosacral junction
- Axial rotation between L1 and L2
- Move closer to its partner facet
- Caused by compression force
approximation of joint surfaces
- Therapeutic traction as a way to decompress
- Move away from partner facet
- Caused by distraction forces
Seperation (gapping) between joint surfaces
- Flexion-extension of the mind to lower cervical spine
- Translates linear or curvilinear direction
- Caused by forced directed tangential to the joint surfaces
Sliding (gliding) between joint surfaces
Lumbopelvic Rhythm
Pelvis & spine rotate in same direction
Ipsidirectional Lumbopelvic Rhythm
Lumbopelvic Rhythm
Pelvis & spine rotate in opposite directions
Contradirectional Lumbopelvic Rhythm
Lumbopelvic Rhythm
Three different lumbopelvic rhythms used to…
flex the trunk forward & toward the floor with knees held straight
Lumbopelvic Rhythm
40° flexion of lumbar spine & 70° of hip flexion
Normal lumbopelvic rhythm
Lumbopelvic Rhythm
Limited hip flexion =
Greater flexion of the lumbar & thoracic spine
Lumbopelvic Rhythm
Limited lumbar mobility =
Greater flexion of the hip joints
- Flexes lumbar spine
- Decreases lordosis
- Shifts nucleus pulposus posteriorly
- Increases the diameter of the intervertebral foramen
Posterior pelvic tilt
- Extends the lumbar spine
- Increases lordosis
- Shifts the nucleus pulposus anteriorly
- Reduces the diameter of the intervertebral foramen
Anterior Pelvic Tilt
Sacroiliac Joint is classified as what type of joint?
Modified synarthrodial joint
- Provides stress relief within the pelvic ring
- Provide a stable means of load transfer bw the axial skeleton & lower limbs
Function of Sacroiliac joint
- Provides stress relief within the pelvic ring
- Provide a stable means of load transfer bw the axial skeleton & lower limbs
Function of Sacroiliac joint
Relative anterior tilt of the base of sacrum relative to ilium
Anterior sacral-on-iliac rotation + Posterior iliac-on-sacral rotation
Nutation (nod) of the SIJ
Relative posterior tilt of the base of sacrum relative to ilium
Posterior sacral-on-iliac rotation + Anterior-on-sacral rotation
Counternutation
Iliac surface is made up of what?
Fibrocartilage
Sacral surface is made up of what?
Hyaline cartilage (3-5x thicker)
- Self-locking mechanism
- “Step-wise” creep deformation
SIJ bony MACROscopic state
