I often get patients presenting to an appointment with a stack of medical records and imaging, stating that their problem is caused by spinal stenosis. It becomes very apparent to me that while those patients can correctly articulate the word stenosis, most are at a complete loss to describe really what it is, much less what it means clinically.
The word stenosis basically means “narrowing”. In the context of the spine, the term stenosis is used to describe the narrowing of a bony passage for important neurological structures. Lateral stenosis describes the narrowing of the passageway of the spinal nerves during their exit from the spinal cord into a limb, and central canal stenosis describes the narrowing of the conduit for the spinal cord behind the vertebra, prior to the point where it sends it to the spinal nerves.
Stenosis is often a degenerative anatomical constant, meaning it is an unchanging narrow space from narrowing of the spinal disc and other overgrowth of other spinal structures. Patients with stenosis however can have significant fluctuation of pain while the stenosis is constant. The explanation is that other, intermittent and modifiable factors will make it better or worse: spine/pelvis/leg alignment, posture shifting, and muscular core deconditioning. This explains why many patients with diagnosed stenosis on an MRI can still report quite a bit of relief from chiropractic care.