To understand more about SA/CRS, it is important to know some basic information about the spine.  Here are front and side views of the spine.

A front view of the spine

A side view of the spine with colors that show different sections related to various muscles that nerves running through the spinal cord control.  The spine is like a tube of bone, and the spinal cord is inside that tube. Nerves from the spinal cord extend out to various parts of the body and provide signals to and from your body and your brain so that you can move and feel.

The spine is divided into different sections. The highest section, at the neck, are the cervical vertebrae, or “C” for short. There are 7 cervical vertebrae, labeled C1 through C7. Below that, between your shoulder blades, are the thoracic vertebrae, or “T” for short. There are 12 thoracic vertebrae, labeled T1 through T12. The curve in your lower back is where the lumbar spine are located.  There are 5 lumbar vertebrae, labeled L1 through L5. The sacral vertebrae are at the end, which connects to the pelvis. There are 5 of them, but they are not separated like the other vertebrae. They all look like one bone, almost like an arrowhead. The coccyx is the end point of the spine.

If the spine and spinal cord are missing below a specific level, such as L2, then the leg muscles and bowel and bladder function will also be impacted. If the spinal cord is missing below T7, then abdominal muscles as well as the hips, knees, feet, bowel, and bladder will have reduced function. Every person with SA/CRS is affected differently by the condition.

In SA/CRS, all or part of the sacrum is missing (as well as the coccyx). Sometimes some or all of the lumbar vertebrae are missing, too, and sometimes some of the lower to mid-thoracic vertebrae are additionally missing. The spinal cord may end at the same point where the spine ends or above or below that point. Sometimes the spinal nerves find their own pathways to various parts of the body. Often individuals with SA/CRS are not able to move some parts of their lower legs or feet but can still feel these parts of their bodies. Sometimes they have increased sensitivity in specific areas of their bodies. The spinal cord may have a “blunt” end or a “tapered” end.

The highest level of spine reported absent among the 1,000+ member iSACRA organization is at the fifth thoracic vertebrae. By contrast, some people are only missing a very small portion of the lowest part of the spine, part of the sacrum. Each individual is different. SA/CRS has been divided into 4 categories or “types”. For information about Renshaw classifications, Click here.