You have provided some confusing information as it appears you have neck and lower back pain but mix these two symptoms up when you describe your pain.
I assume that your lower back is the main pain generator. Your symptoms could possibly be from the “Minor bulging of the L4-5 disc (1mm or less)” but that would be unusual. You might have a pars or facet fracture that might have been missed. I would ask the radiologist to reevaluate the films to look for this possibility. A CT scan might be necessary.
I am a fan of epidural injections. The steroid works well to reduce the inflammation of the nerve roots and this might last for some time. You would need a thorough surgical work-up before any surgical plan would be advised. Your pain generator in your lumbar spine is yet to be discovered.
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.