Lumbar Fusion / Grastoparesis

Lumbar Fusion / Grastoparesis
I had a fusion of the lumbar spine running from L3 through S1, it failed within two weeks after surgery at L3. Thirty days later the doctor took me back into surgery this time to fuse my spine from L2 through S1. I was placed on the following medications, 80 mg of oxycontin, two percocets every two hours and four muscle relaxers per day. Despite continuing to have back and leg pains, I was able to get myself off all narcotics. Four months after the last back fusion and one month after getting off of narcotics for pain, I was diagnosed with Gratroparesis. Could the spinal fusion or the pain medication cause me to develop grastroparesis? I was tested for diabetes, which I do not have.