My surgeon tells me that he expects my fusion to take 6-9 months. He said that my 6 week post-op x-rays are to see if the hardware is still secure and in place - not to look for signs of fusion. Further, that it is impossible to see a fusion on x-ray and success is more or less determined by "how I feel". He said sometimes you "think" someone has a fusion and 2 years later realize it failed when screws start "popping loose".
So, my question is, why are some people reporting signs of fusion at their 6 week post-op visits? I'd hate to think my doctor is mistaken, but I know there are so many different view points on this subject. How does one know when they have a positive fusion? Does a lumbar fusion take longer to grow than a cervical? Same question for a multi-level fusion - does it require more time for a successful union?