Understanding the viscous cycle of injury causing vertebral joint instability and vertebral joint instability causing injury.

Ohtori S, MD, PHD, et al. Pathomechanisms of discogenic low back pain in human and animal models. Journal Spine, March 20, 2014.

Hyper mobility (movement beyond the normal range of motion) is a major factor inducing discogenic (disc related) low back pain. Hypermobility is induced by loss of structural integrity, decreased hydration and an in ability of the affected vertebra and surrounding structures (vertebral motion segment) to withstand load or motion. 

Next, decreased hydration within the central disc, nucleus pulpous, results in decreased disk pressure and reduced disk height. Disc degeneration is characterized by fibrotic tears and clefts within the disc nucleus and annulus with the central nucleus pulposus eventually extruding through the tears and clefts.

Disc herniations are very painful events leading to pain avoidance behavior, increased inactivity or sitting for prolonged periods. Inactivity results in muscle atrophy and eventual fatty infiltration replacing muscle fibers.