Recurrent herniations can originate from a free fragment inadvertently not removed from the disc space or a free intracanal fragment that was “hidden” but subsequently revealed (with relocation after motion) after some obvious fragments were removed surgically creating more space for migration. As you can understand, there is really no way to tell the origin of a recurrent herniation but a microdiscectomy, soon after previous surgery is generally easy to remove. Leg length discrepancy normally is not related.
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.