Improving the Clinical Evidence of Bone Graft Substitute Technology in Lumbar Spine Surgery

摘要

Bone graft substitutes have been used routinely for spine fusion for decades, yet clinical evidence establishing comparative data remains sparse. With recent scrutiny paid to the outcomes, complications, and costs associated with osteobiologics, a need to improve available data guiding efficacious use exists. We review the currently available clinical literature, studying the outcomes of various biologics in posterolateral lumbar spine fusion, and establish the need for a multicenter, independent osteobiologics registry. Keywords: bone graft substitute, spine fusion, biologics, osteobiologics, demineralized bone matrix, ceramics, bone morphogenetic protein, autograft Lumbar spine fusions are performed at a rate of 250,000 per year in the United States alone, 1 and in each case, surgeons are faced with the critical decisions regarding choice of bone graft. In an arena that once demonstrated near-exclusive use of iliac crest bone graft in 1990s, surgeons are now split between the use of growth factors, allograft, demineralized bone matrix (DBM), and ceramics, to name just a few. Despite this transformation to the use of bone graft substitutes to avoid the complications associated with autograft harvest, the comparative and high-quality evidence that researchers and practitioners must rely on is sparse. Although bone regenerative technology research has been conducted for over 4 decades, there has yet to be established an accepted, cost-effective, and efficacious algorithm for patients undergoing lumbar spinal fusion. Outcomes from the use of bone graft substitutes in bone healing are almost nonexistent except for a few commercially available products. The chief reason for this is the expense involved in designing and implementing clinical studies. Though select osteobiologics have been studied in detail, such as bone morphogenetic protein, the resources to obtain similar evidence for other products are often unavailable. Furthermore, even the available data vary substantially in quality, design, outcome measures, and consequently, conclusions. Finally, many products are regulated as “minimally manipulated human allograft” by the Food and Drug Administration (FDA), which does not require a randomized controlled trial or premarket approval for clinical use. Because a large amount data outside of the peer-reviewed literature are often pushed as industry-driven marketing tools, surgeons must actively seek high-quality evidence to make appropriate choices for patient care. Due to the large number of osteobiologics on the market, there exists a need for a focused study group to collect, analyze, and report data. To that end, complications have been reported from the off-label and misuse of bone graft substitutes. Because products are commonly used off-label without formal data, invariably, there is an incomplete understanding of mechanism, tissue response, and proper application before patients are exposed. The most recent fallout of the clinical studies involving bone morphogenetic protein has led to increased scrutiny of data presentation, potential conflicts of interest, and patient safety. 2 As it stands now, the void of an independent organization to study outcomes, costs, and technique makes it difficult to navigate through mere allegations and true fact. This article will review the clinical evidence on bone graft substitutes in lumbar posterolateral spine fusion and present the need for a collaborative effort to improve the available data.