rhontim,
Welcome to the board but sorry to have to meet you under these circumstances.
"At L5-S1 there is desiccation of the disk. There is broad central disk herniation slighly more prominent left of midline displacing the left S1 root dorsally. There is also some facet and ligamentous overgrowth at this level"
L5-S1 disc is the bottom disc in your spine that connects your lurabar area to your sacrum.
Dessication is drying out of center of the disc - the disc normally has a very tough, almost grissly outer shell with an acidic, gel-like inside. As we age the interiors of our disc typically will dry out and there is evidence of this in this disc on you.
broad central disc herniation - broad means large area, central means centrally located toward your back, herniation is a clear area that is protruding out form the disc. This basically means you have a large disc herniation located slightly more to the left which is probably causing you a lot of pain in your lower back and down the back of your left thigh, to the bottom of your heal and outside side of your left foot. I have the same pain - feels great, doesn't it?
displacing the left S1 root dorsally - means your left S1 nerve root is being majorly pinched - ouch.
some facet and ligamentous overgrowth at this level - some abnormality and overgrowth of some of the surrounding bone and ligaments. Not nearly as big of a deal as the major herniation mentioned above.
You will likely need surgery to correct this problem that is likely driving you out of your mind at this point. I would suggest you get to a fellowship-trained neurosurgeon or orthopedic spine surgeon ASAP for evaluation and treatment.
Good luck and let us know how you are doing! Ask any other questions you may have.