A Prospective Analysis of the Efficacy of Allosync Expand and Autograft Bone Graft in Open Lumbar Spinal Fusion

Inclusion Criteria: 1. At least 22years of age at the time of consent 2. Subject must have a documented diagnosis of spondylolisthesis up to Grade I. and have confirmed back and/or radicular pain with associated spinal stenosis as documented by conditions such as: 1. Instability as defined by \>3mm translation or \>5 degree angulation 2. Osteophyte formation of facet joints or vertebral endplates 3. Subject presents with one or more of the following: 1. Radiculopathy 2. Sensory deficit 3. Motor weakness 4. Reflex changes 4. Subject requires lumbar posterolateral arthrodesis at 1-3 contiguous levels (L1-S1). 5. The number of levels decompressed must equal the number of levels fused. 6. Subject must have been unresponsive to conservative care for at least 3 months prior to fusion surgery. 7. Subject must be willing and able to sign an informed consent document. 8. 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. Exclusion Criteria: 1. Subject has had prior lumbar spine fusion surgery at any level. 2. Subject has greater than grade 1 spondylolisthesis of the lumbar spine. 3. Subject is pregnant or nursing or planning to become pregnant during the two years (24 months) following arthrodesis 4. Subject has an active local or systemic infection. 5. Subject is a prisoner 6. Patient has any condition (including malignancy), that in the opinion of the Investigator, would prohibit the patient from complying with and/or completing the protocol