Spine Ligaments

Question 1

Describe the structure and function of zygapophyseal (facet) joints.

Answer 1

Synovial joint with articular cartilage, a capsule, synovial membrane, synovial fluid, and ligamentous support

Function: protect the IVD by limiting movement of the spine

Medially protected by ligamentum flavum and multifidus

Allows for flexion, but also stops flexion past a point to decrease shear on IVD

Question 2

Name the ligaments of the spine.

Answer 2

ALL - anterior longitudinal ligament

PLL - posterior longitudinal ligament

LF - ligamentum flavum

SSL - supraspinous ligament

ISL - interspinous ligament

Question 3

Describe the structure and function of the ALL.

Answer 3

Starts superiorly as the atlanto-occipital membrane, turns into the ALL, and continues to the sacrum

Strong and broad ligament supplied by nociceptive nerve endings

Has anterior and lateral connections

Attaches to PLL and IVD at the rim of the vertebra

Loose against the body to allow blood to enter

Function: stabilization of the spine, prevents hyperextension (ONLY LIGAMENT THAT LIMITS EXTENSION)

Question 4

Describe the structure and function of the PLL.

Answer 4

Extends through foramen magnum to the sacrum, situated anterior to the neural sac (dura mater) and posterior to the body and IVD

Narrower and weaker than the ALL, with the thinnest part being in the L-spine

Attaches to the IVD, not the body, and attaches laterally to the ALL

Supplied well by nociceptive nerve endings, rich venous plexus

Function: prevent IVD from moving into dura, but doesn’t do a great job (herniation)

Question 5

Describe the structure and function of the LF.

Answer 5

Ligamentum flavum - segmental ligament that expands the length of the spine, attaching from lamina to lamina of adjacent vertebrae and blending together in the midline

Broad pale yellow bands of elastin fibers

No nerve supply, commonly have fatty tissue deposits

Increase thickness with aging, can lead to spinal stenosis

Function: reinforce medial capsule of zygapophyseal joint

Question 6

Describe the structure and function of the ISP.

Answer 6

Interspinous ligament - segmental ligament that attach spinous process to spinous process of adjacent vertebrae

Thin and membranous

Fibers attach to ligamentum flavum and fan horizontally to blend with supraspinous ligament

Nociceptive nerve endings

Function: resists separation of spinous processes (flexion)

Question 7

Describe the structure and function of SSL.

Answer 7

Supraspinous ligament - cord-like ligament that connects tips of spinous processes

Merges superiorly with ligamentum nuchae and continues from C7 to the sacrum

Question 8

Describe the structure and function of intertransverse ligaments.

Answer 8

Consist of scattered fibers in the C-spine, fibrous cords in the T-spine, and thin/membranous in the L-spine

Function: connects adjacent transverse processes

Question 9

Describe the structure and function of the IST complex.

Answer 9

Situated in the lumbar spine

IST complex consists of the posterior thoracolumbar fascia that attaches to the supraspinous ligament which blends into the interspinous ligament

Function: prevent excessive compression on spinal cord