There are two questions you pose. One is if surgery could be indicated. The other is whether surgery is safe for your father’s age and medical condition.
The second question first. Diabetes (blood sugar) and heart disease by themselves in a 64 year old do not preclude surgery. The amount of heart disease (lets say complete blockage of the left anterior descending coronary artery) would preclude surgery until that condition is taken care of (heart cath). The skill of the anesthesiologist would be important as this makes a big difference.
Is surgery necessary? You do not indicate the symptoms that your father complains of to determine if surgery will be helpful. See the section “How to describe symptoms” to explain what impairment your father exhibits.
The radiologist also did not use descriptors to indicate severity (mild, moderate or severe) of the nerve or cauda equina compression. There is a big difference between “mild compression” and “severe compression”. Again, the descriptor is in the eyes of the beholder. The radiologist might use moderate to describe compression while I might find the compression “severe”.
Dr. Corenman
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.