Hi, welcome to our site. I am Dr Saumya Mittal. Read your query. That is a very significant question and i appreciate your problem. I will try my best to answer your query I dont think it has much to do with the medicines I think it is because of your neck. There are nerves that arise from the spinal cord. They come out through small apertures between the bones. there is a possibility that during the fusion, these apertures were narrowed. this causes undue pressure on the nerves. this may lead to symptoms like pain, tingling, numbness and weakness. the symptoms are usually bilateral but more severe on one side. so the uncomfortable feeling you have is probably numbness I would suggest repeating an MRI of the spine. I hope this helps you. Inform the reports mentioned above so i can be of help further. Best of luck. I have given you the answer to the maximum considering the information provided. The results of the tests could further enhance my answer to you. Please do understand that some details could be extracted from a detailed history and examination. Looking forward to your return query with the details asked so that I can help you further. (If the answer has helped you, please indicate this)