710241 - Posterior Bone-graft Options and Success in Single-level Circumferential Lumbar Fusions
Thursday, February 27, 2020
8:05 AM – 8:10 AM
Location: Ballroom B
Participants should be aware of the following financial/non-financial relationships:
Glenn R. Buttermann, MD, MS: Dio Medical (Individual(s) Involved: Self, Products/Services: interbody devices): Consulting; Solco FG (Individual(s) Involved: Self, Products/Services: Anterior lumbar plate): Licensing agreement
Background: Achieving spinal fusion requires bone graft and is most reliable using an anterior/posterior technique. Anterior fusion, due to the large bony surface area between the vertebral bodies, results in reliable fusion. Instrumentation which gives stability also increases the fusion rate. The bone graft for the posterior fusion may come from a variety of sources. Historically, bone graft was obtained from the iliac portion of the patient’s own pelvis, IBG, but this may result in additional postoperative pain or morbidity. Alternatives are currently the most common form of bone graft, but there is very little knowledge as to the superiority of one alternative over another. Biologics containing stem cells are an attractive option since they may have inductive properties.
Aim: To determine the ability to achieve a solid posterior single-level spinal fusion using sources of bone graft derived from IBG, bone morphogenic protein (BMP), or from allograft bone alone or combined with stem cells derived from either autologous bone marrow aspirate (BMA) or donor bone, fat, or amniotic membrane/fluid.
Study Design/Setting: Prospective randomized single-blinded clinical study of 7 comparative groups with 27 patients in each group.
Eligible Population: Adults with advanced DDD who underwent single-level circumferential lumbar spinal fusion.
Patient Accountability: 168 of 189 patients (89%) completed 1-2 year follow-up.
Outcomes Measures: VAS back and leg pain, pain drawing, ODI, pain medication usage, and procedure success. High resolutions CT scans at one year postoperative assessed fusion rates between groups. Costs of graft materials was compared.
Methods: HRQOL were obtained prospectively and followed for 1-2 years. All single-level circumferential fusions used BMP anteriorly and instrumentation. Patients were randomized into 7 groups with a different type of bone-graft used posteriorly. Inclusion/exclusion criteria included laminotomy type decompressions but excluded patients who required full laminectomy.
Results: The mean age of patients was 52 y/o of which 96% had CT scans which found solid interbody fusion in 98% of patients. However, solid posterior fusions varied between groups: 98% IBG, 93% BMP, 83% concentrated BMA, 71% bone allograft derived stem cells, 64% fat derived stem cells, and 62% for amniotic tissue derived stem cells. Clinical improvement was significant from pre-op to 1-2 year follow-up within all groups (p < .01 for all outcomes scales). Outcomes were similar between all groups for all outcomes measures. Outcomes were independent of posterior fusion status, however adjacent level degenerative conditions had a trend to adversely affect outcomes. Overall narcotic usage decreased from 62% to 26% of patients. Self-assessment of surgery success varied from 78% to 93%. Costs related to posterior fusion biologics varied between groups: NA for IBG, $3451 for BMP, $1660 for concentrated BMA, $2727 for bone allograft derived stem cells, $2768 for fat derived stem cells, $2216 for amniotic tissue derived stem cells, and $160 for morcellized allograft bone.
Conclusion: One-level circumferential spinal fusion using IBG was the most reliable and cost-effective graft material. BMP was highly effective and the most expensive. Concentrated autologous BMA had moderate fusion success and cost. Allograft products with varying cellularity were marginally effective for their high cost.