Use of Trinity Evolution Bone Matrix Shows High Success Rate in Single-Level Anterior Cervical Discectomy and Fusion
Commentary by Raymond J. Linovitz, MD and Andrew C. Hecht, MD
Patients who underwent single-level anterior cervical discectomy and fusion (ACDF) with the viable cellular bone allograft Trinity Evolution in combination with a PEEK interbody spacer and supplemental anterior fixation had a 93.5% fusion rate at 12 months in a recent study. No serious allograft-related adverse events occurred in these patients, as reported in the July issue of the European Spine Journal.
“Importantly, this prospective study had no exclusions for those clinical conditions known to be associated with an increased incidence of non-unions such as diabetes, use of NSAIDs, concurrent tobacco use, etc,” said lead author. “This ‘all-comers’ inclusion criteria approach is very representative of a contemporary spine surgeons everyday practice. Despite these broad, high-risk inclusion criteria, we believe Trinity fusion rates were comparable to the historical literature for autograft and various allografts.”
The investigators performed ACDF with a PEEK interbody spacer (Orthofix, Inc., Lewisville, TX, USA) and supplemental anterior fixation on 31 patients with symptomatic cervical degeneration at one vertebral level (ie, between C3-C4 or C6-C7). Trinity Evolution (Musculoskeletal Transplant Foundation, Edison, NJ, USA) was placed within and around each spacer to promote bone growth.
The primary endpoint was radiographic fusion status based on independent review of CT scans and radiographic review of angular motion. The criteria for fusion was the presence of bridging bone across the adjacent endplates as seen on thin cut CT scans in addition to angular motion from flexion/extension X-rays.
Efficacy Data at 6 and 12 Months
Fusion rates of 78.6% were found at 6 months and 93.5% at 12 months. Significant improvements in neck function and neck/arm pain were found at both time points (P<0.05 for both).
Seventy-five percent of the study participants were current or former smokers, diabetic, overweight, obese or extremely obese and considered to be at high risk for bone growth failure. Fusion rates were relatively high in these high-risk subgroups as well (Table).
Indication and Safety Profile
“Trinity is regulated by the FDA as an HCT/P [human cellular tissue pathway] allograft and is indicated for all bony procedures including oromaxillofacial, orthopaedic, and spinal surgeries,” Raymond J. Linovitz, MD told SpineUniverse. The product is a cryopreserved allograft that consists of viable cellular cancellous bone matrix and demineralized cortical bone, that include mesenchymal stem cells (MSC) and osteoprogenitors, osteoinductive proteins, and an osteoconductive matrix, the investigators wrote in the paper.
In the current study, 16 patients reported a total of 26 adverse events—including carpal tunnel syndrome, minor pain, numbness, permanent and/or unresolved pain, and swelling—none of which were considered serious. In addition, 5 of the adverse events were considered possibly related to Trinity Evolution.
“Trinity has been implanted in over 150,000 patients without an attributable serious adverse event,” Dr. Linovitz said. Dr. Linovitz added that while there no specific contraindications for use of Trinity Evolution in any PEEK cage, not all PEEK spacers are FDA approved for use with allografts of any kind.
Data From Multilevel Fusions Is Needed
Commenting on the study, Andrew C. Hecht, MD, noted that the success rate in this study is equivalent to that of other existing techniques, but does not suggest an advantage to using Trinity Evolution in 1-level fusions.
“One-level anterior cervical fusion is one of the most successful spine operations, with success rates approaching over 95%. The rate of nonunion is very low whether you use allograft, autograft, or bone graft substitutes,” said Dr. Hecht, who is Associate Professor of Orthopaedics and Neurosurgery at Mount Sinai Hospital in New York, NY.
Dr. Hecht would like to see data on use of Trinity Evolution in multilevel fusions, which pose a greater risk for nonunion. Such data would provide data on whether this new option provides an advantage over existing techniques, he said.
Dr. Hecht pointed to a 2016 study by his colleague Sheeraz A. Qureshi, MD, showing no benefit to using live mesenchymal stem cell (MSC) allograft over standard allograft for 1- or 2-level ACDF. In fact, patients in the MSC cohort showed a nonsignificant trend toward lower fusion rates (87.7% vs 94.7% in the non-MSC cohort).
Orthofix, the developer of Trinity Evolution, recently submitted a paper for publication documenting the researchers results in 2-level ACDF cases, Dr. Linovitz said.