Goal of the Study?
Logically, one would think that an intervertebral disc with internal disruptions would be more likely to experience a disc herniation. Currently, especially in physiotherapy, there is a push to steer away from concepts of disc damage for the fear of fear avoidance in patients. In this research1, published in the European Spine Journal by a prominent anchor author, Hans Wilke PhD, the researchers were curious whether a disrupted disc resulted in a greater chance of a disc herniation.
Why are they doing this study?
Predicting a disc herniation would prevent much disability and cost to the health care system worldwide. Currently, there is a trend to look away at microstructural failures of the disc because some believe that it leads to over-medicalization of back pain and, in turn, leads to over-intervention. Much back pain will resolve in time; however, there are many back pain cases that do get worse. If we could get a clearer picture of which discs may herniate, perhaps fewer disc herniation cases would result.
To better understand which discs may herniate, these researchers looked at thirty ovine spinal segments and subjected them to four different loading conditions. They looked at flexion, lateral bending, axial rotation and axial compression and repeatedly performed complex loading regimes at a loading cycle of 2Hz (two cycles per second) in a loading simulator. See Table 1 in their open access paper for details. Using MRI, they looked at the before and after microstructure of the annulus fibrosis and the intervertebral disc as a whole.
What did they find?
Four of the thirty discs they tested were herniated, and seven experienced nuclear displacements. Only the intervertebral discs with pre-existing microstructural defects were herniated. The authors concluded that internal disruption of the discs weakened the integrity of the discs and set up a microstructural environment for disc herniation. They also wrote that when the discs were subjected to severe levels of postural loading, they were more likely to experience more disc damage.
Why do these findings matter?
Learning how to manage degenerative discs could be helpful. Currently, there are limited long-term strategies for living with disc degeneration which often leads to disc bulging, disc herniation, disc prolapsing and lumbar spinal stenosis. Considering the cost of these conditions on the medical system, it would seem logical to look at how we can prevent many intervertebral states that lead to disability. In this animal research, they concluded that posture and disc herniation are correlated as overloading, and extreme postures, cause discs to herniate.
At Dynamic Disc Designs, we create dynamic human spine models showing dynamic discs to help the low back pain patients clearly understand the postures that are affecting their pain. Educators worldwide are using Dynamic Disc Models to help reduce fears of movement and empower them with the right moves to reduce pain.