Use of Allogenic Mesenchymal Cellular Bone Matrix in Anterior and Posterior Cervical Spinal Fusion: A Case Series of 21 Patients

Abstract

Study DesignRetrospective case series.PurposeTo report our early experience using allogenic mesenchymal cellular bone matrix (CBM) products in cervical spine fusion.Overview of LiteratureMulti-level cervical fusions have historically yielded lower fusion rates than single level fusions, especially in patients with high risk medical comorbidities. At this time, significant literature in cervical fusion outcomes with this cellular allograft technology is lacking.MethodsTwenty-one patients underwent either multilevel (3 or 4 level) anterior cervical discectomy and fusion, anterior cervical corpectomy and fusion, or posterior cervical fusion. ViviGen (DePuy Synthes Spine, Raynham, MA, USA), an allogenic bone matrix product, was used in addition to standard instrumentation. Radiographic evaluation was performed at 2 weeks, 12 weeks, 24 weeks and 1 year postoperative. Visual analog scale (VAS) and neck disability index (NDI) scores along with return to work and leisure activity were recorded.ResultsAt 6 months postoperative, all patients had radiographic evidence of bone fusion regardless of age or medical comorbidities. All patients reported subjective improvement with a mean decrease in VAS from 8.3 to 1.5 and a mean decrease in NDI from 40.3% to 6.0% at 1 year. All patients also returned to work and/or regular leisure activity within 3 months.ConclusionsTwenty-one patients undergoing high-risk anterior and posterior cervical spine fusion, with the use of a commercially available mesenchymal CBM product, went on to radiographic fusion and all had improvement in subjective outcomes. While further effort and research is needed to validate its widespread use, this study shows favorable use of CBM in cervical fusion for high-risk cases.

Allogenic Stem Cells in Spinal Fusion: A Systematic Review

“…At 6 months, the 2 series of Trinity Evolution reported nonunion rates of 34.4% 52 and 21.4%, 53 with lower rates by 12 months (10.6% and 6.5%). While the small series of Vivigen reported no nonunions, 54 the series of Osteocel reported 18% at 24 months with 13% at >24 months. 51 No revision surgeries were reported across 3 series.…”

“…Across case series, criteria and definitions of fusion varied and fusion frequency varied across time frames and intervention products. At 6 months, they varied with rates in 2 series of Trinity Evolution 52,53 of 66% and 79%, respectively, and of 100% in the Vivigen series 54 ; by 12 months, fusion was seen in 89% and 94% of Trinity Evolution recipients. At 24 months, the series of Osteocel reported fusion frequency of 87% 51 (Table 5).…”

“…A small series (N = 21) using Vivigen reported an 85.9% decreased in NDI from baseline and 81.4% decrease in VAS pain at 12 months. 54 The largest series, using Osteocel (N = 135 patients with 24-month follow-up) reported significant improvement at 24 months 51 for both NDI and VAS neck pain and arm pain. However, the authors did not provide data for verification (Table 5).…”

“…The case series include 1 case series using Osteocel Plus, 51 2 case series using Trinity Evolution with local autograft, 52,53 and 1 using Vivigen allograft. 54 Anterior cervical discectomy and fusion (ACDF) was performed in 3 of the 4 series; a variety of procedures was used in the fourth case series. Across studies, ages ranged from 47 to 64 years and proportion of males ranged from 28% to 56%.…”

Development of AOSpine BOnE (Bone Osteobiologics and Evidence) Classification

“…Other materials may have cellular components and may even be marketed as products containing “stem cells”; however, the scientific data that the “stem cells” actually have any effect on fusion is limited to a few peer-reviewed studies with small sample sizes and often without a comparator. 9 - 14 In evaluating the strength of evidence that an osteobiologic has any of the 3 main characteristics, in particular, osteogenic and osteoinductive activity, it is important to have a hierarchy of in vivo over in vitro data. Within in vivo animal models, there is a hierarchy of spine fusion models determined by the species and the time to fusion.…”