Chapter 4 - Lumbar Flashcards
Why are disc herniations more common in the lower lumbar region?
posterior longitudinal ligament narrows -> weakness in the posteriolateral aspect of the IV disc
Where do thoracic & lumbar nerve roots exit the spinal column?
Below its corresponding vertebra (L4 exits b/w L4/L5)
Spinal cord terminates at which level
L1-L2
Muscle of the lumbar spine
Erector spine group (spinals, longissimus, iliocostalis), multifidus, rotatores, quadratus lumborum, iliopsoas (psoas major & iliacus)
Erector spine group
spinals, longissimus, iliocostalis (“SILO”)
iliopsoas origin
T12-L5
iliopsoas insertion
lesser trochanter of femur
iliopsoas action
hip flexor, maintaining lumbosacral angle
iliopsoas dysfunction
prolonged shortening of mm -> PSS, +Thomas test, SD in upper lumbars
Iliac crest level
L4-L5 IV disc
Umbilicus level
L3-L4 IV disc
Most common anomaly of the lumbar spine
Facet trophism
Facet trophism
asymmetry of the facet joint angles (should align w/ sagittal plane (Backward, Medial), but align w/ coronal plane)
Sacralization
1 or both TPs of L5 articulate w/ the sacrum
Lumbarization
failure of S1 to fuse w/ sacrum
Spina bifida
defect in the closure of the lamina
Spina bifida occulta
no herniation - course patch of hair over defect
Spina bifida meningocele
herniation of meninges
Spina bifida meningomyelocele
meninges & nerve root herniation -> neuro deficits
Major motion of Lumbar spine?
Flexion/extension