⁃ At least 18 years of age at the time of surgery

• Undergoing lumbar spine fusion surgery with one of the following bone grafting options:

∙ Virtuous

‣ Virtuous with Autograft (local bone)

‣ Autograft

‣ Autograft + allograft (cancellous bone chips)

• Subject must have a documented diagnosis of DDD. DDD is defined by back and/or radicular pain with degeneration of the disc as confirmed by medical history, physical examination, and radiographic studies that may include CT, MRI, plain X-ray film, discography, myelography, etc. with one or more of the following findings:

∙ Instability as defined by \>3mm translation or \>5 degrees angulation

‣ Osteophyte formation of facet joints or vertebral endplates

‣ Decreased disc height, on average by \>2mm, but dependent upon the spinal level

‣ Scarring/thickening of ligamentum flavum, annulus fibrosis, or facet joint capsule

‣ Herniated nucleus pulposus

‣ Facet joint degeneration/changes; and/or

‣ Vacuum phenomenon

• Subject may have up to a Grade I Spondylolisthesis of the lumbar spine with clinical manifestations of one or more of the following phenomena:

∙ Radiculopathy

‣ Sensory deficit

‣ Motor weakness

‣ Reflex changes

• Subject must require lumbar posterolateral arthrodesis at 1-2 contiguous levels (L1-S1).

• The number of levels decompressed must equal the number of levels fused.

• Subject must have been unresponsive to conservative care for at least 6 months prior to fusion surgery.

• Subject must agree not to use electromagnetic adjuncts to enhance bone fusion during the course of the study

• Subject must be willing and able to sign an informed consent document.

⁃ Subject must be willing and able to return for all follow-up visits, agree to participate in postoperative clinical and radiographic evaluations and comply with the required study regimen.