The biomechanics of a multilevel lumbar spine hybrid using nucleus replacement in conjunction with fusion.

Background Context: Degenerative disc disease is commonly a multilevel pathology with varying deterioration severity. The use of fusion on multiple levels can significantly affect functionality and has been linked to persistent adjacent disc degeneration. A hybrid approach of fusion and nucleus replacement (NR) has been suggested as a solution for mildly degenerated yet painful levels adjacent to fusion.