Disk Degeneration in 21 Year Olds
During my training, it was assumed that the average adolescent or teenager should have normal disc anatomy. It was assumed that disc herniation/degeneration was a rare occurrence in that population. But, at that time, technology such as a MRI scanner was relatively new, rare and expensive. We did not have the capability to test to see if our assumptions were correct.
Now, at least in the United States, we do have more technology available to study these assumptions. In the past 10 years, there has been significant numbers of studies looking at back pain in our teens and young adults to see how back pain correlates to diagnostic studies (mainly MRI’s).
First, there were studies about the incidence of lumbar disk abnormalities in elite 17 year old (on average) asymptomatic tennis players. It turns out that 84% have some abnormalities to the spine, although not all specific to the disk.
Additional studies identified degeneration at high rates for teenage gymnasts, and football players, with and without symptoms.
There are more studies that now look at the general public. A recent study followed a population that was born in 1986 in Finland. The data collection included Lumbar MRI studies on 558 people (325 female, 233 male) taken when the age was approximately 21. 54% of this population had evidence of disk degeneration.
After further examination of the data, this Finnish study concluded “High BMI at 16 years was associated with lumbar DD at 21 years among young males but not among females. High pack-years of smoking showed a comparable association in males, while physical activity had no association with DD in either gender. These results suggest that environmental factors are associated with DD among young males.”
Obviously, more studies need to explore the natural history of disk degeneration in our teens and young adults. However, from these studies, information suggests disk degeneration is much more common amongst this population than formerly thought. And, based on lack of symptoms on many of those examined, we still do not know why some hurt, and others do not from the disk degeneration process.