High lumbar noninstrumented fusion rates using lamina autograft and Nanoss/bone marrow aspirate

BACKGROUND Patients with marked osteoporosis and/or obesity/morbid obesity and severe multilevel lumbar stenosis and other pathology often undergo multilevel laminectomies with non instrumented posterolateral fusions (PLF). The other pathology may include combinations of degenerative spondylolisthesis/lysis, foraminal/far lateral discs, and/or synovial cysts requiring more extensive facet resections. Presently, spine surgeons often use bone graft expanders to supplement the lamina autograft harvested in the course of laminectomy/decompressions for the PLF mass. METHODS In 59 patients, we prospectively analyzed the fusion rates following multilevel laminectomies/noninstrumented fusions using lamina autograft and the bone graft expander Nanoss (RTI Surgical Alachua, FL, and USA) with autogenous bone marrow aspirate (BMA). Patients averaged 66.1 years of age; many exhibited marked osteoporosis (48 patients) and obesity (13 of 27 morbidly obese). Magnetic resonance (MR) and computed tomography (CT) studies documented stenosis/ossified yellow ligament (OYL) and degenerative spondylolisthesis (51 patients)/lysis (2 patients), synovial cysts (32 patients), and disc herniations (10 of 21 far lateral). Patients were followed remove up for an average of 3.12 years. RESULTS Average 4.0 level laminectomies/1.2 level noninstrumented fusions utilized lamina autograft and Nanoss/BMA. Both X-ray/CT studies performed an average of 4.9 months postoperatively documented a 97% fusion rate (57 of 59 patients). Two patients with severe osteoporosis, morbid obesity, and smoking histories exhibited pseudarthroses; neither was sufficiently symptomatic to require secondary surgery. CONCLUSIONS Fifty-nine patients with multilevel lumbar stenosis/OYL and other pathology underwent multilevel lumbar laminectomies/noninstrumented fusions using lamina autograft and Nanoss/BMA. Both dynamic X-ray/CT studies confirmed a 97% fusion rate an average of 4.9 months postoperatively. Nanoss/BMA contributed to a high posterolateral lumbar non instrumented fusion rate without complciations.