Decline in Separate Incision Autograft for Spine Surgery Over the Past Decade: A Fading "gold standard".

BACKGROUND:Spinal fusion is a common procedure for which bone grafting is a critical component. Although iliac crest (separate incision autograft) is typically referred to as the "gold standard" grafting material, it seems to be used less and less frequently. METHODS:The 2010 to Q3 2020 MSpine PearlDiver data set was used to identify patients receiving separate incision autograft versus local autograft/allograft/graft supplement for spinal fusion. Grafting trends over the decade were determined. Patient age, sex, Elixhauser Comorbidity Index, smoking status, insurance plan, region of the country where the surgery was conducted, and surgeon specialty were characterized and compared by the type of bone graft using univariate and multivariate analyses. RESULTS:Of 373,569 spinal bone grafting procedures, separate incision autografts were used for 32,401 (8.67%). A gradual decline was observed from 2010 (10.57% of spinal grafting procedures) to 2020 (4.69%, P -value < 0.00001). Independent predictors of having had a separate incision autograft in order of decreasing odds included surgeon specialty (relative to neurosurgery, orthopaedic odds ratio [OR], 2.45), smoking status (relative to nonsmokers, smokers OR, 1.45), region of the country (relative to Midwest, Northeast OR, 1.11; West OR, 1.42; and South OR, 1.48), insurance (relative to commercial, Medicare OR, 1.14), younger age (OR, 1.04 per decade increase), and lower Elixhauser Comorbidity Index (OR, 0.95 per two-point increase) ( P < 0.0001 for each). CONCLUSION:Iliac crest autograft continues to be referred to as the gold standard grafting material for spine fusions. However, the use of this has faded over the past decade to only 4.69% of spinal fusions in 2020. While some patient factors had an effect on when separate incision autograft was used, nonsurgical factors, including surgeon specialty, geographic region where the surgery was conducted, and insurance factors, suggested that external factors/physician training influence this choice.