If the postoperative symptoms were restricted to the upper extremities, I'd say they were a complication of the surgical procedure. That is, there is irritation or damage to the nerve roots affected in the distribution of the original degenerative changes which led to the operation in the first place. However, the lower extremity problems don't fit. After all, if you have degenerative spine disease in the cervical spine, you are at risk for the same in the lumbar spine. It's wear and tear.
People can get leg numbness iwth cervical spine problems.
Once this is established, only then can someone try to figure out the process that caused the problem and then suggest whether or not it might be treatable. Symptoms overlap somewhat, but the terms refer to specific portions of your nervous system which are involved, and using them indiscriminately may actually mislead your doctor and delay appropriate treatment. I hope this helps. This infromation is provided for your medical education. Specific comments regarding diagnosis, prognosis, and treatment options must come from your doctor after appropriate evaluation.