Your doctor determined from your last set of X-Rays that you have arthritis in your spine and you're not sure how it got there. Was it the physical stress of your job? The 15 years of bowling with your friends in a league? Or maybe the accident you were in when you were a teenager? It's hard to know.
When it comes to arthritis, the cause is not necessarily what you DID, but more what you HAVEN'T BEEN DOING. Do you maximize the range of motion in your body every day? Do you have your spine checked regularly for Subluxations? Joints are worn down faster when they're stuck and misaligned. That's why it's important to keep them aligned and moving with regular Chiropractic care.
Blaming the activities in your life for your arthritis is like blaming the sidewalk for scuffing your shoes. Things naturally wear down when you use them over time, this includes your spine. Instead of worrying about the wear and tear you have, start doing something NOW to slow down the process. Getting adjusted more often is a good place to start.