My brother-in-law is going in to have c4-c6 removed and replaced with cadaver bone in ten days. I'm not completely familiar with all the details, but I know it is something I would never even consider. It just sounds too invasive, risky, and dangerous to me.
My husband had the same issue of herniated discs c5, c6, c7, (not c4). After months of conventional treatment costing tens of thousands of dollars, he finally went to a chiropractor. It was one adjustment. Took about 5 minutes and cost $15. It completely fixed his pain, numbness, tingling, headaches. I don't know if some chiropractors are more experienced or what, but I do know it fixed my husband's issues by at least 98%. Some people go to a chiropractor, and don't feel they see fast results, so I assume some are just "better" at what they do than others are? I just know when the neurologist suggested surgery to my husband, he went to the chiropractor instead. And he never had to go back to the neurosurgeon.
I would suggest to anyone that they at least think about seeing a GOOD chiropractor before having invasive surgery. I can't tell you what differentiates a "Good" one from an "average" one, but do try to get a good one. I know it worked for my husband.