“The spine is the center of the body’s universe, from a mechanical point of view as well as an energetic one, since the main chakras exist here. The spine is active in all asanas, even in a restful state like Savasana, where it acts as a conduit for subtle energies and messaging. The spine supports and balances the trunk and head in standing, sitting, kneeling, back-bending, and arm-balance postures. It connects the upper and lower extremities and protects the spinal cord, which merges with the brain. Along with the articulating ribs, the thoracic spine houses the heart and lungs, and the lumbar/sacral areas protect sexual and other organs.” (Staugaard- Jones 2015)
The muscles that work the spine stabilize and move its four different areas: cervical, thoracic, lumbar, and sacral (minimal movement here). The fifth section, the coccyx, is immovable because its vertebrae are fused, but it does provide support and protection as weight is transferred while sitting.
Cervical – Considered the most movable area of the spine. As in any yoga posture, a main goal is to create space in the body, not condense it; that is why it is important to extend, not hyperextend, the posterior neck position and to not compress the vertebrae.
Thoracic – This is of the longest section of the spine. Its main limitation is hyperextension (arching the back, as in Ustrasana, camel pose). Each person is different, but most have a natural kyphotic curve in this section (posterior) and a backbend creates the opposite. Backbends are aided more by the lordotic areas of the spine (the lumbar and cervical areas), as well as by the upper part of the thoracic region, where bony limitation (one bony process coming into contact with the next) is not as severe. Feeling length in the spine as the back bridges will help one perform with more ease and also protect the discs of the spine (cartilage between the vertebrae) by engaging proper muscles to support the back-bending and to allow openness of the front of the body.
Lumbar – This section of the spine contains the five largest and thickest spinal vertebrae. The main limitation is rotation, because of the shape of the bones. This knowledge is important, especially when a spinal twist is performed. Many injuries of the lower back in yoga can happen because a twist is forced more through the lumbar spine than through the thoracic spine.
Sacral – The four to five vertebrae in this part of the spine have fused together, causing the formation of the sacrum bone, which solidifies through the years and bears the weight of the spinal column. The vertebrae themselves do not move, but at the junction of the sacrum with the pelvis (the sacroiliac, or SI, joint) there is a gliding motion. The sacral area of the spine, although not very movable, can be irritated. One should take care in intense forward-bending poses, twists, and wide-leg straddles that can lead to SI joint discomfort, as ligaments cannot easily “bounce back” to their original length. Sitting too much can also irritate this region
In basic backbends such as the cobra, make sure that the spinal extensors are doing the work and not the arms. The hands can beused to press into the floor to increase the stretch of the front of the body while the core remains engaged. If the lumbar spine is compromised, separate the feet and engage the core more effectively
The spine can twist best when each vertebra is stacked on top of the other first, before rotation begins.