Lumbar Anatomy

Question 1

Regions of Lumbar

Answer 1

• Thoracolumbar junction (T12-L1)
• Mid-Lumbar (L2-L4)
• Lumbosacral junction (L5-S1)

Question 2

How do the facets for lumbar vertebrae face?

Answer 2

In the sagittal plane!

Question 3

____ pressures change drastically based on position. ____ increases pressure, ____ decreases pressure

Answer 3

• Vertebral disc
• Flexion
• Lying down

Question 4

Why are lifting mechanism important?

Answer 4

• It relates to disc pressures and injury risk!

Question 5

What are the ligaments of the Lumbar Region?

Answer 5

• Anterior Longitudional Lig
• Posterior Longitudional Lig
• Ligamentum Falvum
• Interspinal lig
• Supraspinous lig

Question 6

Why is ligamentum flavum and the PLL an important ligament to consider in the lumbar region?

Answer 6

• PLL: It is wide at L1 but narrows as it goes to L5; L4-L5 and L5-S1 are the most problematic spots due to thinning.
• LF: At full disc height, LF stretches out in a healthy position. As we age, disc height shrinks and the ligament will wrinkles into lateral forament and take up space becoming problematic

Question 7

What are some anterior and posterior muscles of the lumbar?

Answer 7

Anterior:
* Rectus Abdominus
* External Oblique
* Internal Oblique
* Transverse Abdominus

Posterior:
* Multifidus
* Quadratus Femoris
* Lattisimus Dorsi

Question 8

2 Primary Foramen of lumbar spine

Answer 8

• Central foramen
  – Spinal cord/cauda equina passes through
• Intervertebral foramen
  – Corresponding spinal nerve root of the body ABOVE passes through
  – Ex: L4 nerve root passes through the L4-L5 intervertebral foramen

Question 9

Spinal cord ends at ____

Answer 9

L1-L2

Question 10

What is unique to nerve roots leaving the lumbar spine?

Answer 10

• They exist before the disc on that level so it does not get compressed
• Ex: L4-L5 disc buldge; L4 is fine but L5 gets compressed

Question 11

How can cauda equina syndrome occur in the spine?

Answer 11

• Large central disc buldge in the lumbar
• Leads to compression of S2, S3, S4 (All innervate bladder)
• Results in hyporeflexive bladder due to compression of LMN’s thus filling of the bladder
• Similar to autonomic dysreflexia by resulting in issues with BP and is an emergency!

Question 12

Innervations to Lumbar Vertebrae

Answer 12

• Outer edge of annulus fibrosis is innervated
• Dorsal Root Ganglion exist is a very vulnerable spot to compression
• Medial branch of dorsal innervates the facet joint and also innervate multifidus

Question 13

What else lies in the lumbar region that is important?

Answer 13

• Sympathetic trunk (Anterior aspect to spine)
• Consider biopsychosocial applications to LBP

Question 14

What important structure also lies on the anterior aspect of the vertebrae?

Answer 14

• Abdominal Aorta; Susceptible to Aneurysm
• One Sx is LBP!