Between 18 and 75 years of age

Treatment at one or two adjacent levels between L3 and S

Have not responded to at least 6 months of non-operative, conservative management

Have symptomatic degenerative disc disease (DDD) demonstrated by signs and/or symptoms of disc herniation, osteophyte formation, or loss of disc height

Osteopenia or osteoporosis

Have a history of endocrine or metabolic disorders. Have rheumatoid arthritis or other autoimmune disease or a systemic disorder such as HIV or active hepatitis.

Prior intra-abdominal or retroperitoneal surgery that would make the approach prohibitively dangerous, or prior anterior surgery at the same level

Have uncontrolled insulin dependent type 1 or type 2 diabetes

Require a treatment (e.g., posterior element decompression) that destabilizes the spine.

Isolated radicular compression syndromes, especially due to disc herniation

Bony lumbar stenosis, pars defect, increased segmental instability, spinal deformities, spondylolisthesis above 3mm at the involved level(s)

Radiological confirmation of severe facet joint disease or degeneration