Ch.40 LBP Flashcards
Lumbar vertebra get larger as you travel __.
Caudally
The lower 3 vertebra are more ___ shaped anteriorly allowing __.
Wedge; normal lumbar lordosis
What are pedicles designed to do?
Resist bending & transmit forces back & forth to posterior elements
What structures create the zygapophyseal joints?
Superior & inferior articular processes
What is the pars interarticularis?
Part of lamina b/w superior & inferior articular processes subject to fx from bending forces
What is the primary shock absorber in the intervertebral disc?
Annulus fibrosus
At what joints do the majority of spinal flex/ext occur?
L4-5 & L5-S1 contributing to high incidence of disc problems
What is the MC direction of disc herniation?
posterior lateral d/t thing lateral fibers of posterior longitudinal ligament
What does the anterior longitudinal ligament resist?
Ext, translation & rotation
What does the posterior longitudinal ligament resist?
Flexion
Which direction causes disruption of longitudinal ligaments?
Rotation
Which ligament is pierced when performing lumbar punctures?
Ligamentum flavum
What are the erector spinae muscles?
Iliocostalis, longissiumus, spinalis
What do multifidi do?
Segmental stabilizers, control lumbar flexion & provide spine proprioception
What does the quadratus lumborum do?
Side bending & flexion of lumbar spine
How can the psoas cause back pain?
increase lorodosis & force on posterior elemens causing zygapophyseal pain
What is an important abdominal muscle in tx LBP?
Transversus abdominis
How does glut weakness cause LBP?
Pelvic instability causes lumbar SB & rotation inc torsional forces on discs
What can a tight piriformis cause in the spine?
Inc shear forces at lumbosacral junction
What dec the pressure on lumbar discs when lifting?
Keeping the load close to your body
Where does the conus medullaris end?
L2
What do the ventral primary rami innervate?
Limbs
What do the dorsal primary rami intervate?
Posterior 1/2 of vertebra, paraspinal muscles & zygapophyseal joints
What does the medial branch innervate?
zygapophyseal joints & lumbar multifidi
What is substance P?
Neuropeptide known to modulate sensory nociceptive feedback
What is the venous engorgment theory in spinal stenosis?
Spinal veins dilate, causing congestion & dec BF causing inc epidural/intrathecal pressures & neuroischemic insult l/t neuritis
What is the aterial insufficiency theory of spinal stenosis pain?
Defective reflex spinal artery dilation during to lower limb exercise
