Disk Injuries

This week I wanted to go over what I consider a seminal paper. This paper looked at the presence of things like spinal degeneration, disk bulges and other imaging features in individuals without pain. 

This paper came about because it is very common to see things on a diagnostic image, like an x-ray or MRI that does not actually impact what someone is experiencing. The question became what are normal changes to the body from aging and what are pathologic changes? To start to answer this question, they looked at images of individuals that do not have pain across a wide age range. They looked at images from 3110 individuals ranging from 20 to their 80s. 

First some definitions. Disk degeneration is a condition where the disk between the vertebrae loses height, and we start to see bone spurs appear and typical “arthritic” changes in the joint. A disk bulge is where we see the out layer of the disk starting to push into the spinal canal. This comes from the inner layer of the disk starting to migrate backwards. A disk protrusion is also known as a herniation and this is where the inner fluid of the disk has ruptured through the disc into the spinal canal. 

They found that disk degeneration was found in 37% of 20 year olds and 96% of 80 year olds. 30% of 20 year olds had disk bulges, as did 84% of 80 year olds. Disk protrusion was present in 29% of 20 year olds and 43% of 80 year olds. Now we want to remember that all of these individuals had 0 pain. 

I consider this a seminal paper because it completely changes the framework of how we view spinal pain, and the treatment of it. This led the researchers to declare this “Our study suggests that imaging findings of degenerative changes such as disk degeneration, disk signal loss, disk height loss, disk protrusion, and facet arthropathy are generally part of the normal aging process rather than pathologic processes requiring intervention.” This is a marked change where people often considered the presence of something like a disk bulge as a marker for a lifetime of pain and disability. This is not the case. Close to half of the current population have some changes in their spine and have no pain. Clinicians are now tasked with finding the true causes of an individual's pain and cannot pass off one of these age related changes as a pain driver. This shifts the treatment of spine to to be first a conservative approach of exercise, joint mobilization and manual therapy and only progressing to more aggressive if conservative approaches fail. 

So what should a non-clinician take away from this? Just the fact that if you have some changes on imaging, know that it is part of aging and don’t worry about it. How your spine looks on an image does not correlate with having pain. 

Brinjikji W, Luetmer PH, Comstock B, Bresnahan BW, Chen LE, Deyo RA, Halabi S, Turner JA, Avins AL, James K, Wald JT, Kallmes DF, Jarvik JG. Systematic literature review of imaging features of spinal degeneration in asymptomatic populations. AJNR Am J Neuroradiol. 2015 Apr;36(4):811-6. doi: 10.3174/ajnr.A4173. Epub 2014 Nov 27. PMID: 25430861; PMCID: PMC4464797.