4] Lumbar Spine Flashcards
Lumbar spine have what kind of body to do what?
Large vertebral body to support compressive loads
Big or small intervertebral foramen?
Large
Facet joints of lumbar are in what plane?
Sagittal
Facets in lumbar spine favor?
Flexion and extension
Vertebral foramen size increase with?
Decrease with?
Increase with flexion and decrease with extension
Significance of vertebral foramen
Affects nerve root compression
For people with spinal stenosis, you want to do what?
Increase foramen size so flexion
Coupled motions in lumbar spine in FLEXION
Lateral flexion and rotation ipsilateral
Coupled motion of lumbar spine in extension or neutral ?
Lateral flexion and rotation happen in OPPOSITE (contralateral) directions
Which segments have the largest amount of flexion and rotation?
L2-L3
In neutral, if you have limited R side bending, what other motion is limited?
Left rotation
Collagen fibers in lumbar are how many degrees and how are they layered?
120 degrees and layered in opposite direction
How does nutrition work in the discs?
Increased loading during the day makes you lose fluid. Then when you go to sleep at night, spine is relaxed, no compression so the fluids and nutrients return to the disc.
In flexion the disc goes?
Posterior
In extension the disc goes ?
Anterior
Lumbosacral is where and usually how many degrees?
Between L5 and S1 and 30 degrees
Mechanics of lumbosacral angle
Increased angle –> increased lordosis –> increase shear
Lordosis is what mechanism in the pelvis?
Anterior pelvic tilt
For shear force to be greater than compression, how many degrees?
More than 45 degrees greater than compression force
Deep layer muscles lie in what reference to AoR and what does it mean?
Deep layer muscles are closer to AoR so LESS shear and MORE compression
Superficial layer muscles in lumbar do what?
Prime movers
Stabilizing corset
Thoracolumbar fascia
What tightens the fascia?
Transversus abdominis
What applies tension on spinous process?
Hip extensors
What produces cross brace/tension
Glute ax and contralateral lats
What would you work on to stabilize the spine?
Lats
Anterior hoop muscles are?
Rectus abdominis
External obliques
Internal obliques
Transversus abdominis
Function of anterior hoop muscles
Control SIJ and stabilize since theyre attached to pelvis
NORMAL lumbopelvic rhythm actions?
Flexion of lumbar spine then anterior pelvic tilt.
Return is posterior pelvic tilt then lumbar extension.
What would be an abnormal lumbopelvic rhythm?
For flexion if they do the pelvic anterior tilt first and THEN do lumbar flexion
Majority of compression occurs?
80% Interbody joints
20% of compression occurs at
Facets
What will increase facet compression?
Going into lordosis (anterior pelvic tilt)
Shear is limited by?
Facets
This muscle acts on individual segments
Mutifidi
Quadratus lumborum action
Ipsi flexion
Contra eccentric control
What is Spondylolisthesis?
Spinal disorder in which a vertebra slips forward onto the bone below it
With spondylo.. what happens to foramen?
Decrease in size
This ligament is strong and prevents anterior shear
Iliolumbar ligament
Iliolumbar is loaded in ?
Flexion
Iliolumbar lig resists ?
Movement of L5 on S1
With forward bending of the lumbar spine, compression is where and tension is where?
Tension is on Posterior ligaments, muscles and disc.
Compression is on anterior disc.
A mechanism to increase the stability of the lumbar spine
Co-contraction of flexors and extensors
What is more important for stability in lumbar spine?
Endurance
What else can u do abdominal wise to increase lumbar stability?
Increase the pressure by creating extension moment or a stiff structure around spine
Least amount of pressure in spine
Supine
Most amount of pressure in spine
Holding 50N at arms length
What’s less stressful: standing or unsupported sitting?
Standing
