It is possible (but unlikely) that your implant is causing your distress. The Mobi-C is made up of cobalt, chromium, and molybdenum which are common implant metals (which also makes up many total joint implants like knees and hips). I believe you can undergo allergy testing to see if you are sensitive to those metals by visiting an allergist.
Donald Corenman, MD, DC is a highly-regarded spine surgeon, considered an expert in the area of neck and back pain. Trained as both a Medical Doctor and Doctor of Chiropractic, Dr. Corenman earned academic appointments as Clinical Assistant Professor and Assistant Professor of Orthopaedic Surgery at the University of Colorado Health Sciences Center, and his research on spine surgery and rehabilitation has resulted in the publication of multiple peer-reviewed articles and two books.