As well as old leases, you should keep anything that documents the landlord-tenant relationship or supports the items you report on your tax return. If the IRS audits your tax return and you cannot produce the correct verification documents, you may be liable for additional tax and penalties.
The facet joints link the vertebrae together and give them the flexibility to move against each other. The facets are the bony knobs that meet between each vertebra. There are two facet joints between each pair of vertebrae, one on each side.
Spondylolisthesis: A bone in the spine slips forward and out of place, typically in the lower back. The degenerative form of this condition is arthritis, which weakens the joints and ligaments keeping the spine aligned. It can cause a disc to move forward over a vertebra.