When a spinal disc loses stiffness, motion occurs at the damaged joint, leading to instability and increased wear on facet joints.

“Do you see how the majority of the motion now is occurring at the Joint that's lost stiffness Think of it like a knee that has a damaged acl ligament it no longer has the guidance and the rotation motion of the knee which is normal is now substitute with shearing motion so shearing motion • indicates it's the metric for instability so now you can see the shearing instability and now look at the work being performed by the facet joints at the level of the dis being damaged and losing stiffness”