What Causes Degenerative Disc Disease?

In a previous inquiry, someone asked the question, " Can a history of bulimia result in degenerative disc disease?" The answer was dismissive of bulimia as a cause. I'm wondering if this assessment is an understatement?

I have had bulimia/anorexia for over 40 years, on and off- I have been treated for depression/eating disorder inpatient twice.

I also have been treated for cervical pain for over 20 years- injections, PT, and advise from some Drs. to have surgery for degenerative disc disease.

I am now 61, and continue to suffer from neck pain, and also currently pain in my arm/elbow that prevents me from lifting/moving without pain.

My last cervical injections were 6 months ago. PT worked for a while. X-rays/MRI show bone spurs and bone-on-bone in C-5 and C-6 .

My question is, should I have surgery? It is a scary prospect, but at this point in my life, I am willing if it will enable me to be an active participant in the lives of my young grandchildren for many years to come.

Thank you for your response.