The Spinal column is made up of 24 individual interlocking bones known as vertebrae. These vertebrae are split into 3 different sections consisting of 7 Cervical, 12 Thoracic & 5 Lumbar, followed by the Sacrum & Coccyx. Even though the vertebrae in each section look different they all have the same functional components; the body for load bearing, the vertebral foramen to protect the spinal cord & the transverse processes for ligament attachment. In between these vertebrae the intervertebral discs are found, protecting the bones by absorbing shock from body weight, trauma & daily activities such as walking, lifting or twisting.
Spinal discs are made up of 2 parts, a soft gel-like inner portion called the nucleus pulposus & a tough outer ring known as the annulus fibrosus. The nucleus pulposus, mainly consisting of water plus loose networks of collagen fibers, is where shock absorption primarily takes place. Surrounding this inner core, the annulus fibrosus is composed of tough ligamentous fibers which protect the nucleus pulposus, as well as securely connecting the vertebrae above and below the intervertebral disc.