Summary Lumbar Spine Anatomy

Lumbar Spine Anatomy




- 5 vertebrae, lordosis
- Vertebral canal protective function of the spinal cord and cauda equina,
spinal cord terminates at L1
- Weight bearing function and dynamic stability
- Allows flexion, extension and side flexion but minimal rotation
- Superior articular facet is concave and face medially and posteriorly, they
articulate with the inferior articular facets which face laterally and
anteriorly
- The transverse processes are long and thin and provide attachments for
ligaments and muscles


Intervertebral Disc
-Provide stability and shock
absorption
-The annulus fibrosis forms
concentric circles of collagen the
outer layers of the disc
-The nucleus pulposus is a semi
fluid like structure
-Vertebral end plate is permeable
barrier for transport of nutrients

, Ligaments
-

-
Anterior longitudinal ligament-
anterior of vertebral bodies, supports
lumbar spine and resists movement
into extension.
Posterior longitudinal ligament- attach
to posterior side of vertebral body
inside the vertebral canal, support the
vertebral bodies and resist flexion.
Ligamentum flavum- attaches from
lamina to lamina, high level of elastin,
supports the spine and controls
stability during lateral flexion and
flexion.
Interspinal ligament- attach between
the lengths of the spinous processes,
prevents separation of spinous
processes during flexion.
Supraspinous ligament- over the top of
each spinous process, prevents
separation of spinous processes during
flexion.




Muscles


Multifidus:
A- bilaterally extend, unilaterally
rotate
O- sacrum and transverse processes.
I- spinous processes.
Quadratus lumborum:
A- unilaterally side flex, bilaterally
assist extension.
O- posterior iliac crest
I-last rib and L1-L4 transverse
processes