He is correct in most statements but I am not assured that you have a fusion at C5-6. This level might be stable with adhesions but a fusion is not obvious (unless an MRI or CT is definitive). The level at C4-5 I believe he is spot on. You already know what instability is from my prior discussion.
What is Chronic Ligamentous Instability at C4-5? This is the inability of the facets and ligaments to hold the vertebra above stable to the vertebra below. This is both a bony facet and a ligament issue.
Subluxation is a partial dislocation. The vertebra above should not slide forward or backwards on the vertebra below. Your C4 moves about 3mm on C5 making this a mild instability.
Dr. Corenman
PLEASE REMEMBER, THIS FORUM IS MEANT TO PROVIDE GENERAL INFORMATION ON SPINE ANATOMY, CONDITIONS AND TREATMENTS. TO GET AN ACCURATE DIAGNOSIS, YOU MUST VISIT A QUALIFIED PROFESSIONAL IN PERSON.
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.
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.