Are spondylosis and spondylothesis the same thing?

No spondylosis is : Spine degeneration with aging but accelerated by factors such as smoking, deformity, obesity to name a few. Genetics play a role. It may lead to instability ; deformity or even spinal stenosis. Disc surgery will accelerate process as can a fusion leading to adjacent level changes. Spondylolithesis is an instability of spine that can arise from spondylosis but can be genetic or from injury.