Come over to the back board to read more about lumbar issues from those of us that have first-hand experience.
Just to give you a general idea about your MRI, and keep in mind that members are not doctors...since this was being compared to a previous MRI, I cannot say to what extent the herniated disc and facet joint issue are worse or better than previously...but...
I think the main issue is that issues at the two lowest lumbar segments of the spine are pushing into the thecal sac. This is the tough membrane that encompasses the spinal cord (until it ends at T-12/L-1) and the spinal nerves that bundle together below this level. Because the thecal sac surrounds nerves, when anything pushes into it, it narrows the space inside that is needed for the nerves to pass freely...and thus, can result in pain...pain in the lower back and pain that radiates out to the limbs.
Specifically, the herniated disc at L5-S1 is slightly worse than previously...and it is pushing into the thecal sac and the S1 nerve. The S1 nerve innervates the back of the leg and runs toward the outside of the foot into the little toe. If you are experiencing pain running down the back of your leg, this is the cause of it...and it is because the disc at L5-S1 is damaged. (all the other words are describing where the disc bulge is pushing out).
It also mentions "There is minimal disc extrusion inferiorly on today's study." Extrusion is where the disc has actually broken through the outer membrane of the disc...and it sounds like this is better than in the last MRI.
The other issue is with the facet joint at L4-L5...which shows some signs of arthritic change, probably some enlargement of the joint which is again pushing into that thecal sac. The facet is a synovial joint just like the other synovial joints in the body like the knee or shoulder, etc. When there is hypertropy, it means the joint has enlarged and is swollen. This is now taking up some space that is needed by the spinal nerves, and again, this can be a source of pain.
I'm not sure how much impact you sustained in the two car crashes, but unfortunately, impact can bring on spinal arthritis more quickly than it would normally develop.
Hope this helps.