Low back pain affects approximately _____ of US population
80%
The lumbar spine supports...
The weight of the trunk
True or False? As you go down the spine, the vertebral bodies get larger.
True. This happens to increase the support.
L5-S1 segment is a..
Transitional segment
What is possibly the most important segment in the spine?
The L5-S1 segment
The L5-S1 segment allows and limits...
Movement of the trunk
Which segment of the spine is the most common source of musculoskeletal pain?
L5-S1
True or False? Transitional vertebrae has only a small relationship with lower back pain
TRUE
How many lumbar vertebrae do you usually have?
5
Sacralization
L5 on sacrum = 4 vertebrae
Lumbarization
S1 unfused = 6 vertebrae
True or False? The bodies of lumbar vertebrae are large
TRUE
In regards to A-P height of L1-L4 bodies, the anterior height ____ posterior height
0
L5 is _______ shaped
Wedge
In regards to A-P height of the L5 body, the anterior height _____ posterior height
>
In the lumbar spine, the transverse and spinous processes are..
Large
In the lumbar spine, why are the transverse and spinous processes large?
They are large to accommodate number and size of muscle attachments
Lumbar facet orientation is mostly in a _____ plane
Sagittal
The concavity of the superior process of the lumbar facet faces..
Posteromedially
The convexity of the inferior process of the lumbar facet faces..
Anterolaterally
What motion does the lumbar facet orientation allow?
1) Flexion
2) Extension
True or False? There is very little rotation allowed in the lumbar spine.
TRUE
Intervertebral disc is almost like..
A semipermeable membrane due to the fact that it allows fluid to move through
The intervertebral disc includes..
1) Anulus fibrosus
2) Nucleus polposus
The annulus fibrosis is made up of..
Type I collagen fibers
True or False? The annulus fibrosis is the largest avascular part of the body
TRUE
Another component of the annulus fibrosis is..
Concentric lamellae
The concentric lamellae allow the annulus fibrosis to be..
A strong structure
The nucleus pulpous is made up of..
Type II collagen fibers
Where is the nucleus pulpous located?
Posteriorly in the anulus
The nucleus pulpous is a..
Thick, gel-like substance (liquid)
The thick, gel-like substance that makes up the nucleus pulpous is..
Incompressible
What happens to the intervertebral disc when you have compression?
1) Radiates forces radially to annulus
2) Anterior annulus becomes more stiff
3) Segment becomes more stable
The end plate is important for..
Nutrition
The end plate is responsible for _____ fluid exchange
10-20%
What characteristic is unique to lumbar discs?
Posterior concavity
The posterior concavity that is unique to lumbar discs increases..
1) Strength of posterior annulus
2) Resistance to lumbar flexion
The vertebrae and disc is largest in which region of the spine?
Lumbar region
Due to the size of the vertebrae and the disc in the lumbar spine, there is more..
Total passive resistance to movement
Lumbar intervetebral movement includes..
1) Flexion
2) Extension
3) Lateral Flexion
4) Rotation
What happens at the lumbar Z-joints during FLEXION?
1) Superior facet glides superiorly on the inferior facet
2) Tensions joint capsule
What happens to the lumbar disc during FLEXION?
1) Compression of annulus anteriorly
2) Anulus fibrosus tensioned posteriorly
During FLEXION, there is a tendency for the nucleus pulposes to be pushed..
Posteriorly (slightly)
What are the segmental limitations of FLEXION in the lumbar spine?
1) Joint capsules
2) Anulus fibrosus
3) Ligamentum flavum
4) Supraspinous ligament
5) Interspinous ligament
6) PLL
What happens at the lumbar Z-joints during EXTENSION?
1) Superior facet glides inferiorly on inferior facet
2) Joint surfaces tend to approximate
3) Joint capsule is slacked
When is the lumbar spine in closed pack position?
During extension
What happens to the lumbar disc during EXTENSION?
1) Compression of annulus fibrosis posteriorly
2) Anulus fibrosis is tensioned anteriorly
During EXTENSION, there is a tendency for the nucleus pulses to be pushed..
Anteriorly
What are the segmental limitations of EXTENSION in the lumbar spine?
1) ALL
2) Anulus fibrosus
3) Passive tension of anterior muscles
4) Approximation of spinous proccesses
What happens contralaterally at the lumbar Z-joints during LATERAL FLEXION?
1) Superior facet glides superiorly on inferior facet
2) Tensions joint capsule
What happens ipsilaterally at the lumbar Z-joints during LATERAL FLEXION?
1) Joint capsule is slacked
2) Superior facet glides inferiorly on inferior facet
3) Joint surfaces tend to approximate
What happens to the lumbar disc during LATERAL FLEXION?
1) Compression of annulus fibrosis ipsilaterally
2) Anulus fibrosus tensioned contralaterally
During LATERAL FLEXION, there is a tendency for the nucleus pulposes to be pushed..
Contralaterally
What are the segmental limitations of LATERAL FLEXION in the lumbar spine?
1) Anulus fibrosus (mostly)
2) Facet joint orientation
3) Iliolumbar ligament
4) Intertransverse ligament
What happens at the lumbar Z-joints during ROTATION?
1) Ipsilateral facets gap slightly
2) Contralateral facets approximate
When in an upright posture, the lumbar spine only has..
1 degree of rotational motion at each segment
Why does a person in the upright position only have 1 degree of rotational motion at each segment?
Due to the approximation of facet joints
What happens to the lumbar disc during ROTATION?
1) One half of the annulus fibrosis fibers tensioned
2) One half of the annulus fibrosis fibers slackened
What are the segmental limitations of ROTATION in the lumbar spine?
1) Anulus fibrosus
2) Facet joint surface approximation
3) Supraspinous ligament
4) Interspinous ligament
Lateral flexion and rotation tend to be coupled ______ in L1 - L4
Contralaterally
When you side bend to the right, vertebrae are rotating ______ in L1 - L4
Left
Lateral flexion and rotation tend to be coupled ______ in L4 - S1
Ipsilaterally
When you side bend to the right, vertebrae are rotating ______ in L4 - S1
Right
The lumbar spine motion segment is the..
Functional unit of the spine
The lumbar spine motion segment includes..
1) Body - disc - body
2) 2 Z-joints
True or False? If you change movement in one portion of the lumbar spine motion segment, there HAS to be change in the other two parts
TRUE
The lumbar spine is designed for..
Sagittal plane motion (Extension and flexion)
The lumbar spine is poorly suited for..
Transverse plane motion (Rotation)
Intrinsic Ligaments of the Lumbar spine include..
1) ALL
2) PLL
3) Interspinous ligament
4) Supraspinous ligament
5) Ligamentum flavum
6) Intertransverse ligament
Intrinsic ligaments of the lumbar spine: ALL
1) Longest and strongest in the lumbar spine
2) Reinforces anterior part of the anulus
Intrinsic ligaments of the lumbar spine: PLL
1) Tapers as it descends
2) Very thin in lumbar spine
Intrinsic ligaments of the lumbar spine: Interspinous ligament
1) Continuous with the ligamentum flavum
Intrinsic ligaments of the lumbar spine: Supraspinous ligament
1) Ability to deform
2) Almost tendinous
Why doesn't the supraspinous ligament resist flexion the most?
Because it is almost tendinous
Intrinsic ligaments of the lumbar spine: Ligamentum flavum
1) Under tension all of the time
2) Allows them to keep off nerve roots
3) Has increased amount of elastin fibers
During flexion of the lumbar spine, the ligamentum flavum is..
Slacked
During extension of the lumbar spine, the ligamentum flavum is..
Contracted
Intrinsic ligaments of the lumbar spine: Intertransverse ligaments
Structurally may be more like tendons
Iliolumbar ligament attachments
FROM
Transverse process of L5
TO
Ilium
Lumbar spine dynamic mechanisms
1) Musculature
2) Thoracolumbar fascia
Fibers in the annulus fibrosis are ____ oriented
Obliquely
The annulus fibrosis acts as a..
Shock absorber
The facet joint capsules are the primary limiters of..
segmental flexion
The facet joint orientation limits..
Rotation with approximation
What is the lumbosacral angle?
A line parallel to the superior aspect of S1 and a horizontal line
What is the lumbosacral angle dependent on?
The lordosis
The lumbosacral angle is approximately..
30 degrees
What contributes to the lumbosacral angle and pelvic tilt?
The fact that L5 is wedge-shaped
L5 - S1 Z-joint Characteristics
1) Biplanar to limit rotation and anterior translation
2) Transitional segment
3) Designed to take more wear and tear (shear and tension)
4) Greater shear forces with lumbosacral angle
Trunk flexion from standing is controlled..
Eccentrically by extensors
Lumbar spine flexors: characteristics
1) Inactive with quiet stance
2) Balance against the extensors
Lumbar spine flexors: muscles
1) Rectus abdominis
2) Internal and external obliques
3) Psoas
The fact that psoas is a flexor muscle in the lumbar spine is dependent on..
Posture
If you have an increased lordosis, the psoas muscle acts as..
An extensor
If you have a decreased lordosis, the psoas muscle acts as..
A flexor
Lumbar spine extensors: characteristics
1) Counters flexion moment by gravity in stance
2) Sustain activity
3) Powerful
4) Usually working hard
True or False? The lumbar spine extensors can compress the lumbar spine.
True. This increases stability.
When are the lumbar spine extensors not working hard?
If the person is hyperlordotic
Lumbar spine extensors: muscles
1) Erector (extensor) spinae muscles
a) Iliocostalis
b) Longissimus
c) Spinalis
Lumbar spine rotators/lateral flexors: characteristics
1) Often coupled functionally
Lumbar spine rotators/lateral flexors: muscles
Internal and external obliques
Lumbar spine lateral flexors: muscles
1) Quadratus lumborum
2) Iliopsoas
The iliopsoas muscle attaches into..
The vertebrae disc
What are the combined movements of the lumbar spine and pelvis during overall forward bending?
1) Lumbar flexion
2) Hip flexion
During forward bending, the gluteus maximus and hamstrings..
Contract eccentrically
Lumbopelvic rhythm during forward bending is initiated with..
Lumbar flexion then anterior tilting of pelvis by relative flexion of the hips
When you return to the upright position after bedding forward, the lumbopelvic rhythm..
Is concentric (reversal)
In a flexed position, lifting causes..
1) Extensor spinae to be less efficient
2) Increased intra-discal pressure
Lifting: valsalva
1) Increase intra-abdominal pressure
2) Increase stability of the trunk
3) Increase blood pressure
More efficient lift includes...
1) Reduce the speed of the lift
2) Reduce the external load
3) Reduce the length of the external moment arm
4) Increase the length of the internal moment arm
In regards to lifting, what is the greatest factor of efficiency?
Horizontal distance
Lumbar spine pathologies include..
1) Spondylolysis
2) Spondylolisthesis
3) Lumbar disc herniation
Spondylolysis is..
A reaction/fracture at pars interatricularis
Spondylolysis is aka..
A stress fracture
Spondylolysis occurs due to..
Shear forces
True or False? There is NO displacement in spondylolysis.
TRUE
Spondylolysis occurs in ______ of the population
7-9%
Spondylolisthesis is..
A reaction/fracture at pars interatricularis that includes forward and inferior displacement
True or False? There is potential for neural encroachment with spondylolisthesis
True. IV foramen can decrease if greater displacement which then leads to encroachment of nerve roots
True or False? Spondylolisthesis has a detrimental effect on the disc.
TRUE
Spondylolisthesis is found in children as young as..
7
Spondylolisthesis occurs in ______ of the population
9-13%
True or False? The majority of people with spondylolisthesis are asymptomatic
TRUE
When is spondylolisthesis found to be symptomatic?
1) In active people (especially people who extend often)
a) Gymnasts
b) Linebackers
c) Etc
What are the three types/phases of lumbar disc herniation?
1) Protrusion
2) Extrusion
3) Sequestration
Lumbar disc herniation: Protrusion
1) Deformation of outer wall
2) Nucleus is still contained
3) Usually asymptomatic
Lumbar disc herniation: Extrusion
1) Nucleus has broken through anulus
Lumbar disc herniation: Sequestration
1) Nucleus has broken though annulus
2) Part of nucleus has separated itself from the main body
What happens when part of the nucleus has separated itself from the main body in a lumbar disc herniation?
1) Body sees it as a foreign body
2) Sets off inflammatory respose
Spinal cord ends..
L1/L2
If spinal canal is compromised, you are more likely to..
Damage nerve roots
The spinal nerve root is most vulnerable..
Posterolaterally
What nerve is affected during a lumbar disc herniation?
The nerve exiting below the level of herniation
True or False? Facets increase with age
TRUE
True or False? The posterior disc bulges with age
TRUE
What are the boundaries of the IV foramen?
1) Pedicle notches
2) Posterior disc
3) Posterior bodies
4) Articular processes
5) Z-joint and capsule
6) Ligamentum flavum
Nerve root occupies ____ of the IV foramen
20%
The IV foramen gets ______ with flexion
Bigger
The IV foramen gets ______ with extension
Smaller
The sciatic nerve is comprised of roots from..
L4-S3
The sciatic nerve gives rise to..
1) Tibial nerve
2) Fibural (peroneal) nerve
The sciatic nerve is tensioned with..
1) Hip flexion
AND
2) Knee extension
(Straight leg raise)
Myotomes of hip flexion are..
L1, L2
Myotomes of hip extension are..
L5, S1
Myotomes of knee flexion are..
L5, S1
Myotomes of knee extension are..
L3, L4
Myotomes of ankle dorsiflexion are..
L4
Myotomes of ankle plantar flexion are..
S1, S2
Myotomes of 1st metatarsal extension are..
L5