A prospective clinical and radiographic 12-month outcome study of patients undergoing single-level anterior cervical discectomy and fusion for symptomatic cervical degenerative disc disease utilizing a novel viable allogeneic, cancellous, bone matrix (trinity evolution™) with a comparison to histori Osteocel Plus Cellular Allograft in Anterior Cervical Discectomy and Fusion: Evaluation of Clinical and Radiographic Outcomes From a Prospective Multicenter Study Prospective nonrandomized comparison of an allograft with bone morphogenic protein versus an iliac-crest autograft in anterior cervical discectomy and fusion. A Prospective Randomized Clinical Trial Comparing Bone Union Rate Following Anterior Cervical Discectomy and Fusion Using a Polyetheretherketone Cage: Hydroxyapatite/B-Tricalcium Phosphate Mixture versus Hydroxyapatite/Demineralized Bone Matrix Mixture MULTILEVEL ANTERIOR CERVICAL FUSION USING A COLLAGEN‐HYDROXYAPATITE MATRIX WITH ILIAC CREST BONE MARROW ASPIRATE: AN 18‐MONTH FOLLOW‐UP STUDY Smoking as a Predictor of Negative Outcome in Lumbar Spinal Fusion Autologous versus allogenic bone grafts in instrumented anterior cervical discectomy and fusion: a prospective study with respect to bone union pattern A Prospective, Randomized, Controlled Cervical Fusion Study Using Recombinant Human Bone Morphogenetic Protein-2 With the CORNERSTONE-SR™ Allograft Ring and the ATLANTIS™ Anterior Cervical Plate The use of a hollow polymethylmethacrylate cervical spacer with plating in the treatment of single level cervical disc disease. Mesenchymal stem cell allograft as a fusion adjunct in one- and two-level anterior cervical discectomy and fusion: a matched cohort analysis.
Purpose This multicenter clinical study was performed to assess the safety and effectiveness of Trinity Evolution ® ( TE ) , a viable cellular bone allograft , in combination with a PEEK interbody spacer and supplemental anterior fixation in patients undergoing anterior cervical discectomy and fusion ( ACDF ) . Methods In a prospect i ve , multi-center study , 31 patients that presented with symptomatic cervical degeneration at one vertebral level underwent ACDF with a PEEK interbody spacer ( Orthofix , Inc. , Lewisville , TX , USA ) and supplemental anterior fixation . In addition all patients had the bone graft substitute , Trinity Evolution ( Musculoskeletal Transplant Foundation , Edison , NJ , USA ) , placed within the interbody spacer . At 6 and 12 months , radiographic fusion was evaluated as determined by independent radiographic review of angular motion ( ≤4 ° ) from flexion/extension X-rays combined with presence of bridging bone across the adjacent endplates on thin cut CT scans . In addition other metrics were measured including function as assessed by the Neck Disability Index ( NDI ) , and neck and arm pain as assessed by individual Visual Analog Scales ( VAS ) . Results The fusion rate for patients using a PEEK interbody spacer in combination with TE was 78.6 % at 6 months and 93.5 % at 12 months . When considering high risk factors , 6-month fusion rates for patients that were current or former smokers , diabetic , overweight or obese/extremely obese were 70 % ( 7/10 ) , 100 % ( 1/1 ) , 70 % ( 7/10 ) , and 82 % ( 9/11 ) , respectively . At 12 months , the fusion rates were 100 % ( 12/12 ) , 100 % ( 2/2 ) , 100 % ( 11/11 ) and 85 % ( 11/13 ) , respectively . Neck function , and neck/arm pain were found to significantly improve at both time points . No serious allograft related adverse events occurred and none of the 31 patients had subsequent additional cervical surgeries . Conclusions Patients undergoing single-level ACDF with TE in combination with a PEEK interbody spacer and supplemental anterior fixation had a high rate of fusion success without serious allograft-related adverse events Study Design . Prospect i ve , multicenter , nonr and omized , institutional review board-approved clinical and radiographic study . Objective . To evaluate and summarize the 2-year outcomes of patients treated with Osteocel Plus cellular allograft as part of an anterior cervical discectomy and fusion procedure . Summary of Background Data . Osteocel Plus is an allograft cellular bone matrix containing native mesenchymal stem cells and osteoprogenitor cells that is intended to mimic the performance of iliac crest autograft without the morbidity associated with its harvest . Methods . A total of 182 patients were treated with anterior cervical discectomy and fusion using Osteocel Plus in a polyetheretherketone cage and anterior plating at 1 or 2 consecutive levels . Clinical outcomes included visual analogue scale for neck and arm pain , neck disability index , and SF-12 physical and mental component scores . Computed tomography and plain film radiographic measures included assessment of bridging bone , disc height , disc angle , and segmental range of motion . Results . A total of 249 levels were treated in 182 patients .  Mean procedure time was 100 minutes , blood loss was less than 50 mL in 93 % of patients , and hospital stay was 1 day or less in 84 % of patients . Significant ( P < 0.05 ) average improvements in clinical outcomes from preoperatively to 24 months included the following : neck disability index : 21.5 % ; visual analogue scale neck : 34 mm ; visual analogue scale arm : 35 mm ; SF-12 physical component score : 11.2 ; SF-12 mental component score : 6.8 . At 24 months , 93 % of patients were satisfied with their outcome . In patients treated at a single level with a minimum of 24-month follow-up , 92 % ( 79/86 ) of levels achieved solid bridging and 95 % of levels demonstrated range of motion of less than 3 ° . In combined single- and 2-level procedures , 87 % ( 157/180 ) of levels achieved solid bridging and 92 % ( 148/161 ) had range of motion of less than 3 ° at 24 months . No patient required revision for pseudarthrosis . Conclusion . Improvements in clinical results at 2 years , high patient satisfaction , and high radiographic and clinical fusion rates provide confidence in Osteocel Plus as an effective alternative to structural allograft or autograft in anterior cervical discectomy and fusion procedures . Level of Evidence : BACKGROUND CONTEXT Anterior cervical discectomy and fusion ( ACDF ) using autogenous iliac bone graft may lead to donor-site morbidity . This has led some surgeons to use alternatives to iliac bone graft , but often the alternatives have greater rates of nonunion and delayed union . Bone morphogenic protein ( BMP ) studies have found high arthrodesis rates in lumbar fusions . PURPOSE The objective of this pilot study was to compare the success of BMP combined with bone allograft with iliac bone autograft in ACDF patients . STUDY DESIGN / SETTING The institutional review board approved a prospect i ve but nonr and omized study of 66 consecutive patients who had primary one- to three-level ACDF with either iliac-crest bone autograft or BMP allograft ( 0.9 mg BMP per level ) followed prospect ively over a 2- to 3-year period . PATIENT SAMPLE Consecutive patients who had primary one- to three-level ACDF with either iliac-crest bone autograft ( n=36 ) or BMP-allograft ( n=30 ) . Patients in both iliac bone graft and BMP-allograft groups had comparable preoperative pain and disability . OUTCOME MEASURES Visual analog scale pain , pain drawing , Oswestry index , pain medication use , opinion of treatment success , and neurological recovery . RESULTS Given the nonr and omized nature of the study , the study groups were not matched . Within this limitation , both groups of patients had similar improvement in all outcome scales ( visual analog scale pain , pain drawing , Oswestry index , pain medication use , and opinion of treatment success ) and neurological recovery over the 2- to 3-year follow-up period . Patients in the iliac bone graft group had two pseudarthroses and two complications of the iliac-crest donor site . In the BMP-allograft group , one patient had a pseudarthrosis , but 50 % had neck swelling presenting as dysphagia , which was substantially more common than the 14 % present in the iliac bone graft group . Patients in the BMP-allograft group had slightly shorter surgery time , but implant and hospitalization costs were higher . CONCLUSIONS ACDF performed with BMP ( 0.9 mg BMP per level ) allograft is as effective as iliac bone graft in terms of patient outcomes and fusion rates . Safety concerns related to neck swelling and higher initial costs were associated with patients in the bone morphogenic protein group Study Design Prospect i ve r and omized noninferiority trial . Purpose To evaluate whether the union rate of anterior cervical discectomy and fusion ( ACDF ) using a polyetheretherketone ( PEEK ) cage filled with a mixture of hydroxyapatite ( HA ) and demineralized bone matrix ( DBM ) is inferior to that of a mixture of β-tricalcium phosphate ( β-TCP ) and HA . Overview of Literature There have been no clinical trials investigating the outcomes of a mixture of HA and DBM in a PEEK cage in ACDF . Methods Eighty-five eligible patients were r and omly assigned to group B ( n=43 ) , in which a PEEK cage with a mixture of HA and DBM was used , or group C ( n=42 ) , in which a PEEK cage with a mixture of HA and β-TCP was used . The primary study endpoint was the fusion rate , which was assessed with dynamic radiographs and computed tomography ( CT ) scans . Secondary endpoints included pain intensity using a visual analogue scale , functional outcome using a neck disability index score , laboratory tests of inflammatory profiles , and the infection rate . Results Seventy-seven patients ( 38 in group B and 39 in group C ) were included in the final analysis . One year postoperatively , bone fusion was achieved in 87 % of group B patients and 87 % of group C patients on dynamic radiographs , and 87 % of group B patients and 72 % of group C patients on CT scans ( p=1.00 and 0.16 , respectively ) . There were also no between-groups differences with respect to the secondary endpoints . Conclusions A HA/DBM mixture inside a PEEK cage can provide noninferior outcomes compared to a HA/TCP mixture in ACDF OBJECTIVE The pseudarthrosis rate after multisegment anterior cervical fusion is directly related to the number of levels surgically fused . The advent of osteobiological adjuvants offers an opportunity to reduce both the likelihood of failed arthrodesis and the need for posterior instrumentation . Collagen-hydroxyapatite matrix is osteoconductive and has been used with autogenous bone marrow aspirate ( BMA ) to promote fusion . We report our results of using collagen-hydroxyapatite matrix with BMA for multilevel anterior cervical discectomy and fusion and anterior cervical corpectomy and fusion ( ACCF ) . METHODS Sixty-six consecutively treated patients underwent a multilevel anterior cervical discectomy and fusion and /or ACCF during a period of 16 months . In all cases , a Smith-Robinson decompression was performed followed by allograft fibula strut grafting filled with collagen-hydroxyapatite matrix and BMA , and anterior semiconstrained cervical plating . A vacuum chamber was used to draw the BMA slowly through the collagen-hydroxyapatite sponges . No patient underwent simultaneous posterior instrumentation . Clinical outcome was determined by an independent observer who evaluated patients on the basis of symptom and neurological examination results . Radiographic fusion was determined by dynamic x-rays and computed tomographic scanning during an 18-month follow-up period . RESULTS With the inclusion of discectomies performed in ACCF procedures , patients were fused between two and five disc levels ( mean , 3.1 levels ) . Seventeen patients underwent one to four-level corpectomies ( mean , two levels ) . Clinical improvement was observed in 49 patients . Conditions in nine patients remained unchanged , and two patients had radicular palsies . In all , 60 patients were followed and analyzed for radiographic fusion .  All but two patients demonstrated successful radiographic fusion . CONCLUSION Collagen-hydroxyapatite matrix with BMA can be a safe , effective adjuvant for promoting fusion in multilevel anterior cervical discectomy and fusion and ACCF . Although r and omized , controlled studies are necessary to determine whether or not the fusion rates are superior to those obtained from using allograft alone , these results compare favorably to historical data in the literature Study Design . A review of the smoking habits in 426 patients who had been followed prospect ively for 2 years after a lumbar spinal fusion procedure was conducted . Objective . To analyze the effect of pre- and postoperative smoking on clinical and functional outcome after lumbar spinal fusion . Summary of Background Data . Several animal models have shown a negative effect of nicotine on spinal fusion . At this writing , the clinical effect of nicotine on spinal fusion has not been fully clarified . Methods . The study comprised 426 patients who underwent lumbar spinal fusion between 1993 and 1997 . These patients received a mailed question naire regarding their tobacco consumption before and after their surgery . All other data , including preoperative clinical and functional status , were collected prospect ively during a 2-year follow-up period . To assess functional outcome , the Dallas Pain Question naire was used . Results . The question naire was answered by 396 patients ( 93 % ) . Of these patients , 54.5 % ( 20 % more than the background population ) were smokers before the operation . Smoking of more than 10 cigarettes daily before the operation and attempted fusion at two or more levels increased the risk of nonunion : odds ratio , 2.01 ( P < 0.016 ) and odds ratio , 3.03 ( P < 0.001 ) , respectively . Smoking cessation increased fusion rates to near those of nonsmokers . Smoking had no influence on functional outcome , as assessed by the Dallas Pain Question naire , but preoperative smoking predicted a negative answer to the question “ Would you undergo the same treatment again , now that you know the result ? ” ( odds ratio , 1.65;P < 0.054 ) . Conclusions . Smoking was shown to have a negative effect on fusion and overall patient satisfaction , but no measurable influence on the functional outcome as assessed by the Dallas Pain Question naire Background The purpose of this prospect i ve semi-r and omised comparative study was to compare fusion rates , course of fusion , and occurrence of collapse and subsidence of autologous and allogenic bone grafts in instrumented anterior cervical fusion . The number of fused levels and the smoking status were investigated as potential factors influencing the bone-healing process . No similar prospect i ve study on instrumented anterior cervical discectomy and fusion was found in the literature . Methods Seventy-nine consecutive patients were operated on using the Smith – Robinson technique with a single instrumentation system at one or two levels . Seventy-six cadaverous fibular bone grafts and 37 autologous iliac-crest bone grafts were inserted . All patients were followed up for at least 2 years . Results The radiographs obtained during the follow-up were analysed , and showed no statistical difference in fusion and collapse rate between autografts and allografts . Allografts showed significantly longer time to union . No case of graft migration was observed . No difference was found between fusion and collapse rate with respect to the number of fused levels in general , but greater time to union was seen in two-level fusions . When one- and two-level subgroups were compared , there was no evidence of any significant difference in fusion or collapse rates between autografts and allografts , and the healing process took longer in allogenic grafts . Smoking status did not alter any of the fusion or collapse rates , or the course of bone fusion . Conclusions This study demonstrates that allografts are suitable substitutes for autografts in instrumented ACDF . Prolonged time to union observed in allogenic bone grafts does not seem to be an important factor in instrumented procedures . Two-level grafting does not imply a significantly lower fusion rate , but longer time to union can be expected than with single-level instrumented procedures in both allograft and autograft subgroups . Our relatively small number of patients may not have been sufficient to decipher significant differences between smokers and non-smokers in the rate or course of fusion as previously reported Study Design . A prospect i ve , r and omized , pilot clinical trial compared recombinant human bone morphogenetic protein-2 ( rhBMP-2 ) with iliac crest autograft bone for the treatment of human cervical disc disease . Objective . To examine the safety and effectiveness of using INFUSE ™ Bone Graft ( rhBMP-2 applied to an absorbable collagen sponge ) , as compared with an autogenous iliac crest bone graft placed inside the CORNERSTONE-SR ™ fibular allograft , in anterior cervical discectomy and interbody fusion . Summary of Background Data . Recombinant human bone morphogenetic protein-2 is an osteoinductive protein that induces a reliable fusion in the lumbar spine , but it has not been studied in patients with degenerative cervical disc disease . Methods . For this study , 33 patients with degenerative cervical disc disease were r and omly assigned to investigational or control groups . The investigational group received a fibular allograft ( CORNERSTONE-SR ™ Allograft Ring ) with an rhBMP-2–laden collagen carrier inside the graft along with an ATLANTIS ™ anterior cervical plate . The control group received a fibular allograft with cancellous iliac crest autograft placed inside it , along with an ATLANTIS anterior cervical plate . The patients underwent plain radiographs at 6 weeks , then at 3 , 6 , 12 , and 24 months , and CT scans at 3 and 6 months after surgery . They also completed general health profiles and self-evaluation scales . Adverse events were evaluated for severity , duration , association with the implant , and the need for a second surgical procedure . Results . All the patients evaluated had solid fusions 6 , 12 , and 24 months after surgery . There were no device-related adverse events . At 24 months , the investigational group had mean improvement superior to that of the control group in neck disability and arm pain scores ( P < 0.03 each ) . Conclusions . This pilot study demonstrates the feasibility of using rhBMP-2 safely and effectively in the cervical spine BACKGROUND At present , the use of a cervical cage and plating has become an accepted and widely practice d surgical intervention for the treatment of cervical spondylosis and disc herniation .  Polymethylmethacrylate ( PMMA ) bone cement has been used in cervical disc disease as a spacer , with good longterm outcomes , but the method does not result in solid bone fusion in all cases . METHODS A prospect i ve study was performed with 92 consecutive patients who underwent single-level anterior cervical discectomy and fusion ( ACDF ) with a hollow PMMA spacer , cancellous allograft and titanium cervical plate stabilization between January 2002 and December 2003 . Patients were followed for a minimum of 2 years . RESULTS The surgical procedures used were technically successful for all patients , and there were no major complications related to anesthesia or the overall surgical procedure . The fusion rate was 89.8 % at the 12-month follow-up , and 100 % at the 24-month follow-up . The mean intervertebral disc height was 6.5 + /- 1.5 mm and regained height was 3.4 + /- 1.3 mm at the 24-month follow- up . The mean segmental lordotic angle was 3.7 + /- 2.0 degrees with an increase of 6.1 + /- 2.3 degrees at the 24-month follow-up . There was no hollow PMMA spacer dislodgment or failure . However , 5 ( 5.4 % ) patients had screw loosening and 3 ( 3.3 % ) patients underwent a secondary operation for removal of the plate and screws . CONCLUSIONS The procedure for a single-level ACDF with a hollow PMMA spacer , cancellous allograft and titanium cervical plate stabilization is safe and effective . There were no complications related to the hollow PMMA spacer . This procedure has a high fusion rate , and can restore disc height and maintain normal cervical lordosis . This method achieves results similar to those of other methods BACKGROUND CONTEXT Live mesenchymal stem cell ( MSC ) allograft-containing allogeneic bone grafts have recently gained popularity and currently account for greater than 17 % of all bone grafts and bone graft substitutes used in spinal surgery . Although the cl aim of cellular bone matrices containing osteogenic cells with osteoinductive properties is attractive , little is known about their clinical success when used in anterior cervical discectomy and fusion ( ACDF ) . PURPOSE The objective of this study was to report on the radiographic fusion rates in one- and two-level instrumented ACDF using an MSC . STUDY DESIGN / SETTING This was a retrospective review of prospect ively matched cohort of patients with radiologic assessment of fusion as the primary end point . PATIENT SAMPLE Two matched cohorts of adult patients who underwent ACDF with MSC or st and ard allograft  were included . OUTCOMES MEASURES The outcome measures included radiographic and clinical evidence of healing at 1 year . METHODS A consecutive series of 57 patients who underwent a one- or two-level instrumented ACDF procedure between 2010 and 2012 were retrospectively analyzed . All fusion constructs comprised an interbody allograft , an anterior plate , and Osteocel ( NuVasive , San Diego , CA , USA ) . These patients were matched to a  control group of 57 patients . RESULTS Of the 57 cases in both cohorts , 29 ( 50.9 % ) were single-level , and 28 ( 49.1 % ) were two-level instrumented ACDFs . There were no significant differences in patient age ( p=.71 ) , gender , comorbidity burden ( Charlson Comorbidity Index [ CCI ] : 1.95 ; 2.42 , p=.71 ) or body mass index ( p=.79 ) . At the 1-year follow-up , 50 of 57 ( 87.7 % ) patients in the Osteocel cohort demonstrated a solid fusion compared with 54 of 57 ( 94.7 % ) in the control group ( p=.19 ) . Seven ( 12.3 % ) patients in the Osteocel cohort were reported as having a failed fusion at 1 year . CONCLUSIONS This is the first non-industry sponsored study to analyze a matched cohort assessing the 1-year arthrodesis rates associated with a nonstructural MSC allograft in one- and two-level ACDF procedures . Although not statistically significant , patients treated with MSC allografts demonstrated lower fusion rates compared with a matched non-MSC cohort
To undertake a systematic review of published literature to evaluate efficacy of bone graft substitutes  on radiographic and clinical outcomes in single- or double-level anterior cervical discectomy and fusion ( ACDF ) for degenerative disease .
ACDF is one of the most common spinal surgeries completed in the United States .
Today bone graft substitutes including ceramic-based synthetic bone grafts , allografts , bone morphogenetic proteins ( BMPs ) , mesenchymal stem cells , and bone marrow aspirate are widely used to enhance fusions ; even though the efficacy of these substitutes is poorly defined .
Critical evaluation of these products is necessary to optimize radiographic and clinical outcomes for ACDF in degenerative disease .