In a prospective series, the 24-month fusion status was evaluated radiographically among patients undergoing instrumented posterolateral lumbosacral spinal fusion. Seventy-three patients had a diagnosis of degenerative disk disease or degenerative spondylolisthesis and had supplemental bone grafting with demineralized bone matrix (DBM) putty (Grafton DBM; Osteotech, Eatontown, NJ) enriched with aspirated bone marrow (DBM bone marrow), DBM putty combined with iliac crest autograft (DBM autograft), or autograft. Overall, approximately 63% (12 of 19) of DBM bone marrow, 70% (19 of 27) of DBM autograft, and 67% (18 of 27) of autograft patients were fused at 24 months (P = .875). These findings suggest that both DBM composites offer similar performance to autograft in posterolateral spinal fusion.