Spine Flashcards
Primary ______ occurs at birth while secondary _____ develops with motor maturation and upright posture.
Kyphosis; lordosis
Cobb angles: A flat thoracic spine would [decrease/increase] the angle while excessive kyphosis would [decrease/increase] the angle.
Decrease; increase
The line of gravity passing through the body passes through the _____ side of the apex of each region’s curvature
concave
Gravity produces a torque that helps maintain what?
Optimal shape of each spinal curvature
What must the external torque due to gravity be neutralized by?
Active forces in muscles or passive forces in connective tissues
What does exaggerated thoracic kyphosis do to lung space?
Reduces the space for the lungs to expand during deep breathing
What is a key factor in defining one’s instantaneous posture?
The spacial relationship between the line-of-gravity and the spinal curvatures
Where would the line of gravity pass in a swayback posture? What kind of torque would it produce?
Anterior to the lumbar region; constant flexion torque
What does extension of the trunk create in the different levels of the spine? flexion?
flattens out thoracic, increases lordosis in cervical and lumbar; increases kyphosis in thoracic, flattens out cervical, and flattens out or gives a kyphotic curve in lumbar
What is the mechanical purpose of the transverse and spinous processes?
mechanical outriggers or levers, that increase the mechanical leverage of muscles and ligaments
What is the mechanical purpose of the apophyseal joints?
primarily responsible for guiding intervertebral motion
How are most facet joints oriented?
somewhere between horizontal and vertical
How will facet joints move going into flexion?
The top facet will move superior and anterior (inferior facet will move on the superior facet)
What plane(s) do(es) the Tspine move in? Cspine? Lspine?
Frontal; Horizontal and frontal; vertical, sagittal
How do thoracic facet joints move? how do cervical facet joints move?
A lot of superior movement, a little anterior; superior and anterior
What are the primary functions of inter body joints?
- shock absorption
- load distribution
- stability btwn vertebrae
- site of axis rotation
- functions as deformable intervertebral space
About __% of the total height of the vertebral column is due to discs.
25
The ______ is the shock absorber part of the vertebral disc while the ______ provides support.
Nucleus pulposus; annulus fibrosus
What forces does the annulus fibrosis resist? how does it resist these forces?
distraction, shear and torsion; each layer is oriented in a different direction
Thin caps of hyaline and fibrocartilage located on superior and inferior surfaces of each vertebral body; allow nutrients to pass from blood vessels in the vertebral body to deeper regions of the disc; releases enzymes during injury that make the nucleus pulpous more liquidous
Vertebral endplates
About ___% of a load is carried through the inter body joint while ___% is carried by posterior structures such as apophyseal joints and laminae
80; 20
Displaced nucleus pulposus remains within annulus fibrosus
Protrusion
Nucleus pulpous reaches posterior edge of disc, remains confined
Prolapse
Annulus ruptures, allows nucleus to completely escape from dis into epidural space
Extrusion
Parts of nucleus and fragments of annulus become lodged within epidural space
Sequestriation
The nucleus is [hydrophobic/hydrophilic]
hydrophilic; disc swells during sleep and upright weight bearing forces water out
C1’s superior articular facets are ____ while its inferior facets are _____
Concave; flat to slightly concave
C1’s inferior surfaces facets face inferiorly; lateral edges sloped downward approx ___ degrees from horizontal plane
30
C2’s superior articular processes project laterally from the body; large and flat to slightly convex that have facets that face cranially exhibiting a ___ degree slope
30
A typical cervical vertebrae’s are oriented ___ degrees up from the horizontal plane; superior articular facets face ______ while the inferior facets face _______
45; posteriorly-superiorly; anterior-inferiorly
How many degrees of freedom does the atlanto-occipital joint have? what is it stabilized by?
2; flexion and extension, lat flex is slight); ant and post atlanto-occipital membrane, ant long lig
How many degrees of freedom does the atlanto-axial joint have?
2, axial rotation (½) and negligible flex/ext
How many degrees of freedom do the intracervical apophyseal joints (C2-7) have?
3
What does the tectorial membrane limit?
Extremes of flex/ext
What does alar ligaments limit? what are they clinically referred to as?
Axial rotation of the head and atlas relative to axis and lateral flexion; check ligaments
How do we describe motion at each segmental level?
Close (approximation), Open (separation), and sliding
Which law is defined as
“when the spine is in neutral, side bending to one side will be accompanied by horizontal rotation to the opposite side”
First law
Which law is defined as “When motion is introduced in one plane it will modify (reduce) motion in the other two planes”
Third law
Which law is defined as “When the spine is flexed or extended (non-neutral), side bending to one side will be accompanied by rotation to the same side”
Second law
According to fryette, when you’re standing in neutral position and laterally flex to the right, your spine will rotate to the _____.
left (1st law)
According to fryette, when you flex or hyperextend your spine and you laterally flex to the right, your spine will rotate to ______.
right (2nd law)
According to fryette, when you do any movement in one plane, there __________ in the other planes.
won’t be as much motion (3rd law)
About _____% of sagittal plane motion occurs at the atlanto-occipital and altanto-axial joints.
20-25%
What is the ROM of cervical flexion? extension? total?
45-50; 70-85; 130-135
During cervical rotation, the inferior facets slide _____ and slightly ____ on the same side as rotation, and _____ and slightly _____ on the side opposite the rotation.
posteriorly; inferiorly; anteriorly; superiorly
During cervical rotation, the same [opening/closing] occurs on the side the spine is rotating towards while [opening/closing] occurs on the opposite side.
closing; opening
About ____ the axial rotation occurs at the atlanto-axial joint.
1/2
What is the ROM for cervical rotation
90 degrees per side; 180 degrees total
The inferior articular facets on the side of the lateral flexion slide _____ and slightly _____, while inferior articular facets on the side opposite the lateral flexion slide _____ and slightly _____
Inferiorly; posteriorly; superiorly; anteriorly
What is the ROM of lateral flexion?
40 degrees per side, 80 degrees total (5 degrees may occur at AOJ, but most is C2-C7; AAJ lat flex is negligible)
What is the first ligament to rupture is extreme cervical flexion?
Supraspinous ligament
In C2-C7 spinal coupling, rotation and lateral flexion are in the ______ direction
same
Cervical _______ flexes the lower to mid cervical spine and extends the upper craniocervical region
protraction
Cervical ______ extends or straightens the lower to mid cervical spine
retraction
What is the condition where nerve root in the cervical region is compromised; due to dehydrated/degenerated discs creating increased compression forces
Cervical osteophytes; bone spurs in areas of high stress, can encroach on exiting spinal nerve roots
What are the 3 functions of vertebrae in the cervical region?
- Stable base for muscles to control craniocervical region
- Protects organs
- Mechanical support for breathing
What plane are the thoracic facets in? what is the slope?
frontal plane, 30 degrees
What is a normal spinal angle of thoracic spine? cervical? Lumbar?
40 degrees; 30-35 degrees; 45 degrees
What is a ligament that limits flexion in the lumbar region that is not in the others?
Iliolumbar lig
What’s the difference between spondylosis and spondylolithesis?
Spondylosis = anterior translation (fracture on one side), spondylolithesis = anterior translation with a fracture, grades I-IV (bilateral fracture)
What ligaments stabilize the costovertebral joint?
Radiate and scapular ligaments
What ligaments stabilize the costotransverse joint?
capsular (costotransverse) lig and superior constotransverse ligament
What is the range of motion for thoracic spine in flex/ext? Rotation? Lat flex?
30-40 flex, 20-25 ext, 50-65 tot; 30 rot; 25 lat flex
What is the range of motion for lumbar spine in flex/ext? Rotation? Lat flex?
40-50 flex, 15-20 ext, 55-70 tot; 5-7 rot; 20 lat flex
Flexion in thoracic spine occurs by ______ and slightly _____ sliding of the inferior facet surfaces of superior vertebrae.
Superior; anterior
Does rotation increase or decrease in cranial to caudal spine direction?
Decrease
Juvenile osteoporosis; hereditary disease; associated with kyphosis
Scheuermann’s disease
Compression function in vertebral leads to reduced height in vertebral bodies and increased kyphosis
Osteoporosis
Deformity of vertebral column characterized by abnormal curvatures in all three planes (most notably in the frontal and horizontal)
Scoliosis
Contralateral coupling pattern in scoliosis: Spinous processes of involved vert are rotated in the horizontal plane toward the side of concavity. Which side will rib hump occur?
convex side (of the spinous process)
Which way do the superior facets face in the lumbar region? inferior facets? are they concave or convex?
medial to postero medial (concave); lateral to anterior-lateral (convex)
What plane are the facet joints of the lumbar region oriented in?
Saggital plane (upper lumbar) to midway between sagittal and frontal (lower lumbar)
What plane are the L5-S1 apophyseal joints oriented in?
Frontal
The base of the sacrum is naturally inclined anteriorly and inferiorly forming and approx ___ degree horizontal angle while standing
40
The frontal plane inclination of the facet surfaces of the L5-S1 junction resist ____________.
Anterior shear forces
Sitting reduces lumbar lordosis by about _____ degrees
20-35
Full flexion of the lumbar spin _____ the diameter of the itnervertebra foramina and volume of the vertebral canal. However it generates compression forces on the _____ side of the disc, migrating the nucleus pulpous ______.
Increases; anterior; posteriorly
Opening of the facet joints during flexion occurs as the inferior facets of L2 move _____ and _____ relative to the superior facets of L3.
Superior; anterior
What can sustained flexor positions do to lumbar facet joints?
damage them due to greater contact pressure
What are the abnormal lumbopelevic rhythm?
- Restricted mobility at hip joints (greater flexion at lumbar and thoracic spine)
- lumbar region restriction (greater hip flexion = larger forces required from hip extensors which increase compression force at hips)
What does full extension of the lumbar region do interns of load, contact, diameter of intervertebral foramina and vertebral canal volume, and migration of nucleus pulopsus?
increase load; increase area contact at facet joints; decrease diameter of intervertebral foramina and canal volume (closing); migrates nucleus pulpous anteriorly
ROM for thoracolumbar rotation?
40
Increased lumbar lordosis creates ____ pelvic tilt
Anterior
Sitting in a slouched position, the pelvis is ______ tilted. Overtime it weakens the posterior annular fibrosis, reducing its ability to block a ______ and increased ________ at the base of the C-spine.
posteriorly; protruding nucleus pulposus; muscular stress
What can severe hyperextension do to ligamentum flavum?
Can buckle it inward and pinch the spinal cord
What ligament become taut in lateral flexion?
Inter transverse ligaments
What limits flexion?
- Ligamentum niche
- Interspinous and supraspinous lig
- Ligamentum flava
- Facet capsules
- Posterior annulus
- Posterior longitudinal lig
What limits extension?
- Cervical viscera
- Anterior annulus
- Anterior longitudinal lig
What limits rotation?
- Annulus
- Facet capsules
- Alar ligs
What limits lateral flexion?
- Intertransverse ligament
- Contralateral annulus
- Facet capsule
What is the open pack position for the cervical spine? close pack?
Slight extension; full extension
What is the open pack position for the thoracic spine? close pack?
midway between flexion and extension; extension
What is the open pack position for the lumbar spine? close pack?
midway between flexion and extension; extension
What can happen due to a lumbosacral fracture?
Damage the caudal equina; leads to pelvic floor dysfunction, muscle paralysis atrophy, altered sensation, reduced reflex
What is the sacrum responsible for?
Weight transference (transmits weight of the vertebral column to the pelvis)
The strength of the ________ depends on the fit and stability of the sacrum wedged between two halves of the pelvis
Pelvic ring
What three ligaments primarily reinforce the sacroiliac joint?
- Anterior SI lig
- Interosseous lig
- Short and long posterior SI lig.s
What two ligaments indirectly assist with the stabilization of the SI joint?
- sacrotuberous lig
2. Sacrospinous lig
Nutation occurs by [anterior/posterior] sacral-on-iliac rotation, [anterior/posterior] ilium-on-sacral rotation, or by both motions occurring simultaneously.
Anterior; posterior
What are the two functions of the sacroiliac joint?
- Stress relief within the pelvic ring
2. Stability during load transfer between the axial skeleton and lower limbs
What is the close packed position of the SI joint?
Full nutation
What 3 things create the stabilizing effect through nutation torques?
- Gravity and weight bearing
- Stretched ligaments (sacrotuberous and interosseous ligs which compress SI joint)
- Active muscle force (erector spinal, biceps femurs and rectus abdominis)
Longus capitis and longus colli are_____
craniocervical flexors (longus capitis also laterally flexes)
Rectus capitis anterior is primarily a _____ while rectus capitis laterals is primarily a ______.
Flexor; lateral flexor
What creates a longus colli spasm which leads to weakness?
whiplash
Which muscles/joints are usually under greater strain in an acceleration injury? why?
Anterior; hyperextension occurs over a large range of motion
What is internal torque the product of?
- muscle force generated parallel to a plane
2. IMA length available to muscle
What are the quickest muscles to fail in the erector spinal group?
multifidus
What are the primary extrinsic muscular stabilizers?
- Abdominals
- Erector spinal
- Quadratus lumborum
- Psoas major
- “hip” m’s which connect pelvis with LE
Thick connective tissue sheaths that crisscross as they traverse the midline
Linea alba
What muscle is the dominant vertical stabilizer and increases lumbar lordosis due to anterior pelvic tilt?
Psoas major
What is an example where torque demands are large during activities where body performs high-power axial rotations?
sprinting, wrestling or throwing a discus
What is an example where torque demands are low?
walking
What are 4 ways to reduce the amount of force in lifting?
- Reduce speed of lifting
- reduce magnitude of external load
- Reduce length of EMA (most effector for compression forces)
- Increase length of IMA (lumbar lordosis increases length)
