Ligaments are fibrous bands or sheets of connective tissue linking two or more bones, cartilages, or structures together. One or more ligaments provide stability to a joint during rest and movement. Excessive movements such as hyper–extension or hyper–flexion, may be restricted by ligaments. Further, some ligaments prevent movement in certain directions.
Three of the more important ligaments in the spine are the Ligamentum Flavum, Anterior Longitudinal Ligament and the Posterior Longitudinal Ligament.
Primary Spinal Ligaments Include:
|Alar||Axis – skull||Head rotation & lateral flexion|
|Anterior Atlantoaxial||Axis & Atlas||Extension|
|Posterior Atlantoaxial||Axis & Atlas||Flexion|
|Anterior Longitudinal||Axis – Sacrum||Extension & reinforces front of annulus fibrosis|
|Posterior Longitudinal||Axis – Sacrum||Flexion & reinforces back of annulus fibrosis|
|Ligamentum Flavum||Axis – Sacrum||Flexion|
|Supraspinous||Thoracic & Lumbar||Flexion|
|Iliolumbar||Sacroiliac joints||Stability & some motion|
|Sacroiliac||Sacroiliac joints||Stability & some motion|
|Sacrospinous||Sacroiliac joints||Stability & some motion|
|Sacrotuberous||Sacroiliac joints||Stability & some motion|
|Ligaments of the Back of the Cervical and Upper Thoracic Spine
1. Supraspinous Ligament (flexion)
2. Ligamentum Nuchae (fibrous membrane)
Ligament Systems – Atlas and Axis
As mentioned in the Vertebral Column, the Atlas (C1) and Axis (C2) are different from the other spinal vertebrae. The upper cervical ligament system is especially important in stabilizing the upper cervical spine from the skull to C2. Although the cervical vertebrae are the smallest, the neck has the greatest range of motion.
Occipitoatlantal Ligament Complex (Atlas)
These four ligaments run between the Occiput and the Atlas:
Occipitoaxial Ligament Complex (Axis)
These four ligaments connect the Occiput to the Axis:
Altantoaxial Ligament Complex (Axis)
These four ligaments extend from the Atlas to the Axis:
Cruciate Ligament Complex
These ligaments help to stabilize the Atlantoaxial (Axis) complex:
Understanding the terminology associated with spinal problems is very important as health care providers discuss the problems and the solutions for the spinal disorder with patients and families. This article helps clarify a difficult topic.