The Science of Spinal Stenosis

Spinal stenosis involves narrowing of the spaces within your spinal canal, creating compression of neural structures. This narrowing can occur in the central canal (central stenosis) where the spinal cord or cauda equina travels, or in the lateral recesses and foramina where individual nerve roots exit. The narrowing typically develops gradually through multiple mechanisms. Degenerative changes in the discs can cause bulging into the spinal canal, while arthritis of the facet joints leads to bone spur formation and joint enlargement. The ligamentum flavum, which runs along the back of the spinal canal, can thicken and buckle inward, further reducing available space. As these structures encroach on the neural space, they create a mismatch between the space available and the space needed for optimal neural function. The compression may be positional - worsening when your spine is extended and improving with flexion, which explains why many people find relief when leaning forward or sitting.