Clinician directed use of bone morphogenetic proteins (BMPs) in ways other than FDA approved, has increased recently due to the morbidity associated with harvest of iliac crest bone graft in spinal arthrodesis procedures. FDA approved for the use in anterior lumbar fusions with LT Cage, other clinical applications of these proteins is becoming widely adopted due to their effectiveness in forming bone and facilitating fusion. Clinicians have realized while these proteins are potent stimulators of bone formation there have been anecdotal reports of increased rates of radicular pain in the postoperative period when used in interbody arthrodesis procedures. Speculation as to the mechanism of this radiculitis is postulated to be due to the inflammatory effects of these proteins. Excess bone overgrowth around the spinal nerves in proximity to the fusion cage has been reported. No prospective studies have been performed assessing the incidence and etiology of this complication. The investigators propose a prospective study evaluating the incidence of this complication as well as postoperative imaging studies to help determine whether bony overgrowth is indeed occurring adjacent to the effected spinal nerves.