A greater occipital nerve block (GON) is not the same as a facet block however a GON will help to indicate if the nerve itself is involved. WIth no relief, it is unlikely that the greater occipital nerve is causing your pain. In my practice however, I will still have the patient undergo facet blocks at C2-4 as these facets can also cause base of skull and posterior headache without greater occipital nerve involvement.
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.