For some reason I've been going through a lot of lumbar MRIs recently. Some that I ordered and some that came with patients on their 1st appointments. Central stenosis seems to be the common recurrent theme in all of these patients. Central stenosis describes an anatomical situation where the canal that hosts the spinal cord and the nerves that go to the lower extremity and lower abdominal organs is narrow and potentially causing neurological compression.
The compression can come from a variety of sources including disc herniation's crowding the front of the canal, posterior disc margin bony spurs, congenital narrow canal, degenerative changes that narrowed the vertical dimension, thickening of the posterior canal lining ligaments causing crowding into the posterior canal, chronic posterior slippage of a vertebra (retrolisthesis). The last one on the list is a problem that we are seeing at an increasing frequency on MRI reports called epidural lipomatosis. It describes a phenomenon whereby the normal fat pads on the outside of the spinal cord lining become enlarged and crowd the nerve bundles.
I recently had a very enlightening conversation with 2 seasoned spine radiologist about this phenomenon. For a while this was thought to be an idiopathic finding meaning we did not know what was causing it, however there is very strong new research suggesting that epidural lipomatosis is part of metabolic syndrome associated with high BMI, abnormal carbohydrate and lipid metabolism. The type of fat that makes up the fat pad is very similar to visceral fat, and responds to the same signaling to grow or recede. My long-standing radiologist stated that he has seen a few cases of patient going on very stringent weight loss diets with subsequent follow-up MRIs showing almost complete resolution of the epidural lipomatosis and significant resolution of the central stenosis.
This blog is not meant to beat up on people who already struggling with high BMI and metabolic syndrome. But it can be an encouragement for some people who are wondering if dropping their weight in improving the body composition will have any impact on some of their chronic referred spinal pain. The answer is that it will. Let that be an encouragement to stay the course or to take on the process in the 1st place.
