Demineralized bone matrix composite grafting for posterolateral spinal fusion. Comparison of OP-1 Putty (rhBMP-7) to Iliac Crest Autograft for Posterolateral Lumbar Arthrodesis: A Minimum 2-Year Follow-up Pilot Study Grafton and Local Bone Have Comparable Outcomes to Iliac Crest Bone in Instrumented Single-Level Lumbar Fusions RhBMP-2 Versus Iliac Crest Bone Graft for Lumbar Spine Fusion: A Randomized, Controlled Trial in Patients Over Sixty Years of Age The safety and efficacy of OP-1 (rhBMP-7) as a replacement for iliac crest autograft for posterolateral lumbar arthrodesis: minimum 4-year follow-up of a pilot study. Radiographic Analysis of Fusion Mass Using Fresh Autologous Bone Marrow With Ceramic Composites as an Alternative to Autologous Bone Graft Allograft alone versus allograft with bone marrow concentrate for the healing of the instrumented posterolateral lumbar fusion. Two-year fusion and clinical outcomes in 224 patients treated with a single-level instrumented posterolateral fusion with iliac crest bone graft. Use of Recombinant Human Bone Morphogenetic Protein-2 With Local Bone Graft Instead of Iliac Crest Bone Graft in Posterolateral Lumbar Spine Arthrodesis Efficacy of Silicate-Substituted Calcium Phosphate Ceramic in Posterolateral Instrumented Lumbar Fusion The Fusion Rate of Calcium Sulfate With Local Autograft Bone Compared With Autologous Iliac Bone Graft for Instrumented Short-Segment Spinal Fusion Randomized Radiostereometric Study Comparing Osteogenic Protein-1 (BMP-7) and Autograft Bone in Human Noninstrumented Posterolateral Lumbar Fusion: 2002 Volvo Award in Clinical Studies Accelerating lumbar fusions by combining rhBMP-2 with allograft bone: a prospective analysis of interbody fusion rates and clinical outcomes. Recombinant human bone morphogenetic protein-2 on an absorbable collagen sponge with an osteoconductive bulking agent in posterolateral arthrodesis with instrumentation. A prospective randomized trial. Initial Fusion Rates With Recombinant Human Bone Morphogenetic Protein-2/Compression Resistant Matrix and a Hydroxyapatite and Tricalcium Phosphate/Collagen Carrier in Posterolateral Spinal Fusion RhBMP-2 Versus Iliac Crest Bone Graft for Lumbar Spine Fusion in Patients Over 60 Years of Age: A Cost-Utility Study Fabrication of polycaprolactone-silanated β-tricalcium phosphate-heparan sulfate scaffolds for spinal fusion applications. Healos graft carrier with bone marrow aspirate instead of allograft as adjunct to local autograft for posterolateral fusion in degenerative lumbar scoliosis: a minimum 2-year follow-up study. Development of a per-operative procedure for concentrated bone marrow adjunction in postero-lateral lumbar fusion Use of Recombinant Human Bone Morphogenetic Protein-2 as an Adjunct in Posterolateral Lumbar Spine Fusion: A Prospective CT-Scan Analysis at One and Two Years Evaluation of autologous platelet concentrate for intertransverse lumbar fusion Single-Level Instrumented Posterolateral Fusion of Lumbar Spine With &bgr;-Tricalcium Phosphate Versus Autograft: A Prospective, Randomized Study With 3-Year Follow-up The Efficacy of rhBMP-2 for Posterolateral Lumbar Fusion in Smokers Efficacy of calcium sulfate plus decompression bone in lumbar and lumbosacral spinal fusion: preliminary results in 40 patients. Clinical Outcomes and Fusion Success at 2 Years of Single-Level Instrumented Posterolateral Fusions With Recombinant Human Bone Morphogenetic Protein-2/Compression Resistant Matrix Versus Iliac Crest Bone Graft Instrumented Spondylodesis in Degenerative Spondylolisthesis With Bioactive Glass and Autologous Bone: A Prospective 11-year Follow-up rhBMP-2 for Posterolateral Instrumented Lumbar Fusion: A Multicenter Prospective Randomized Controlled Trial Correlative radiological, self-assessment and clinical analysis of evolution in instrumented dorsal and lateral fusion for degenerative lumbar spine disease. Autograft versus coralline hydroxyapatite A Prospective Randomized Study of Posterolateral Lumbar Fusion Using Osteogenic Protein-1 (OP-1) Versus Local Autograft With Ceramic Bone Substitute: Emphasis of Surgical Exploration and Histologic Assessment Use of Recombinant Human Bone Morphogenetic Protein-2 to Achieve Posterolateral Lumbar Spine Fusion in Humans: A Prospective, Randomized Clinical Pilot Trial 2002 Volvo Award in Clinical Studies A Preliminary Study of the Efficacy of Beta Tricalcium Phosphate as a Bone Expander for Instrumented Posterolateral Lumbar Fusions 1997 Volvo Award Winner in Clinical Studies: Degenerative Lumbar Spondylolisthesis With Spinal Stenosis: A Prospective, Randomized Study Comparing Decompressive Laminectomy and Arthrodesis With and Without Spinal Instrumentation Hydroxyapatite-Bioactive Glass Ceramic Composite as Stand-alone Graft Substitute for Posterolateral Fusion of Lumbar Spine: A Prospective, Matched, and Controlled Study Platelet Gel (AGF) Fails to Increase Fusion Rates in Instrumented Posterolateral Fusions Beta tricalcium phosphate: observation of use in 100 posterolateral lumbar instrumented fusions. Radiographic Assessment of Interbody Fusion Using Recombinant Human Bone Morphogenetic Protein Type 2 Clinical and Radiographic Outcomes of Anterior Lumbar Interbody Fusion Using Recombinant Human Bone Morphogenetic Protein-2 A Pilot Study Evaluating the Safety and Efficacy of OP-1 Putty (rhBMP-7) as a Replacement for Iliac Crest Autograft in Posterolateral Lumbar Arthrodesis for Degenerative Spondylolisthesis Mixture Ratios of Local Bone to Artificial Bone in Lumbar Posterolateral Fusion A Prospective Analysis of Autograft Versus Allograft in Posterolateral Lumbar Fusion in the Same Patient: A Minimum of 1‐Year Follow‐up in 144 Patients An analysis of noninstrumented posterolateral lumbar fusions performed in predominantly geriatric patients using lamina autograft and beta tricalcium phosphate.
In a prospect i ve series , the 24-month fusion status was evaluated radiographically among patients undergoing instrumented posterolateral lumbosacral spinal fusion . Seventy-three patients had a diagnosis of degenerative disk disease or degenerative spondylolisthesis and had supplemental bone grafting with demineralized bone matrix ( DBM ) putty ( Grafton DBM ; Osteotech , Eatontown , NJ ) enriched with aspirated bone marrow ( DBM bone marrow ) , DBM putty combined with iliac crest autograft ( DBM autograft ) , or autograft . Overall , approximately 63 % ( 12 of 19 ) of DBM bone marrow , 70 % ( 19 of 27 ) of DBM autograft , and 67 % ( 18 of 27 ) of autograft patients were fused at 24 months ( P = .875 ) . These findings suggest that both DBM composites offer similar performance to autograft in posterolateral spinal fusion Study Design . A prospect i ve , r and omized , controlled , multicenter clinical study . Objective . To compare the safety and clinical and radiographic outcomes of OP-1 ( BMP-7 ) Putty to autogenous iliac crest bone graft in a population of patients undergoing laminectomy and posterolateral fusion for symptomatic lumbar stenosis associated with degenerative spondylolisthesis . Summary of Background Data . Although the existing pre clinical and clinical data suggest that OP-1 is able to achieve osteoinduction and clinical fusion in a variety of situations , the efficacy of this recombinant protein in a clinical spine fusion population has not been fully eluci date d. This study directly compares the efficacy and safety of OP-1 putty to autograft bone for arthrodesis in patients with symptomatic stenosis in association with degenerative spondylolisthesis . Methods . Thirty-six patients with degenerative lumbar spondylolisthesis and symptoms of neurogenic claudication underwent laminectomy , bilateral medial facetectomy , and posterolateral fusion using either iliac crest autograft or OP-1 Putty .  Oswestry scores and SF-36 question naires were used to determine the clinical response to treatment . Independent , blinded neuroradiologists review ed both static and dynamic radiographs to determine the fusion status . Successful fusion was declared whenthe presence of continuous bridging bone between the transverse processes was observed and less than 5 ° of angular motion and 2 mm of translational movement was measured using digital calipers . Results . Efficacy data were tabulated for 27 patients at the 24-month time point and an additional 4 patients ( without evaluable 24-month results ) at the 36-month time point . One patient was not evaluable for radiology , so the data reflect clinical information for 31 patients and radiology for 30 patients .  Clinical success , defined as a 20 % improvement in the preoperative Oswestry score , was achieved by 17 of 20 ( 85 % ) OP-1 Putty patients and 7 of 11 ( 64 % ) autograft patients . A successful posterolateral fusion was achieved in 11 of 20 ( 55 % ) OP-1 Putty patients and 4 of 10 ( 40 % ) autograft patients . SF-36 scores showed similar clinical improvement in both groups . No systemic toxicity , ectopic bone formation , recurrent stenosis , or other adverse events specifically related to the use of the OP-1 Putty implant were observed . Conclusion . This study represents the first clinical trial to demonstrate the safety and similarity of OP-1 Putty as a replacement for autogenous bone graft in the posterolateral fusion environment with a minimum of 2-year follow-up . OP-1 Putty was able to achieve osteoinduction leading to a radiographically solid fusion in the absence of autogenous iliac crest bone graft in 55 % of the patients at 24 and 36 months . These results compare favorably to the historical fusion rates reported for uninstrumented arthrodesis in this challenging clinical scenario Study Design . Prospect i ve multicenter r and omized clinical trail . Objective . The goal of our 2-year prospect i ve study was to perform a r and omized clinical trial comparing the outcomes of Grafton demineralized bone matrix ( DBM ) Matrix with local bone with that of iliac crest bone graft ( ICBG ) in a single-level instrumented posterior lumbar fusion . Summary of Background Data . There has been extensive research and development in identifying a suitable substitute to replace autologous ICBG that is associated with known morbidities . DBMs are a class of commercially available grafting agents that are prepared from allograft bone . Many such products have been commercially available for clinical use ; however , their efficacy for spine fusion has been mostly based on anecdotal evidence rather than r and omized controlled clinical trials . Methods . Forty-six patients were r and omly assigned ( 2:1 ) to receive Grafton DBM Matrix with local bone ( 30 patients ) or autologous ICBG ( 16 patients ) . The mean age was 64 ( females [ F ] = 21 , males [ M ] = 9 ) in the DBM group and 65 ( F = 9 , M = 5 ) in the ICBG group . An independent radiologist evaluated plain radiographs and computed tomographic scans at 6-month , 1-year , and 2-year time points . Clinical outcomes were measured using Oswestry Disability Index ( ODI ) and Medical Outcomes Study 36-Item Short Form Health Survey . Results . Forty-one patients ( DBM = 28 and ICBG = 13 ) completed the 2-year follow-up .  Final fusion rates were 86 % ( Grafton Matrix ) versus 92 % ( ICBG ) ( P = 1.0 not significant ) . The Grafton group showed slightly better improvement in ODI score than the ICBG group at the final 2-year follow-up ( Grafton [ 16.2 ] and ICBG [ 22.7 ] ) ; however , the difference was not statistically significant ( P = 0.2346 at 24 mo ) . Grafton showed consistently higher physical function scores at 24 months ; however , differences were not statistically significant ( P = 0.0823 ) . Similar improvements in the physical component summary scores were seen in both the Grafton and ICBG groups . There was a statistically significant greater mean intraoperative blood loss in the ICBG group than in the Grafton group ( P < 0.0031 ) . Conclusion . At 2-year follow-up , subjects who were r and omized to Grafton Matrix and local bone achieved an 86 % overall fusion rate and improvements in clinical outcomes that were comparable with those in the ICBG group Study Design . Prospect i ve r and omized controlled trial of rhBMP-2/ACS ( Infuse bone graft ) versus iliac crest bone graft ( ICBG ) for lumbar spine fusion in patients over 60 years of age . Objective . To report on clinical , radiographic , and economic outcomes , at 2-year follow-up , in patients treated by posterolateral lumbar fusion with rhBMP-2/ACS versus ICBG .  Summary of Background Data . RhBMP-2/ACS is widely used “ off-label ” for posterolateral spinal fusion . Despite encouraging initial reports , outst and ing issues include the need for evidence regarding safety and efficacy in an older population ; and an assessment of cost-effectiveness . Methods . Patients over 60 years old were r and omized to rhBMP-2/ACS ( n = 50 ) or ICBG ( n = 52 ) .  Oswestry Disability Index , Short Form-36 , and numerical rating scales for back and leg pain were determined preoperatively and at 6 , 12 , and 24 months postoperatively . Fusion was evaluated by fine-cut computed tomography scan 2 years postoperatively by 3 review ers . All in-patient and subsequent out-patient event costs were recorded by a dedicated hospital coder . Results . Two-year postoperative improvement in Oswestry Disability Index averaged 15.8 in the rhBMP-2/ACS group and 13.0 in the ICBG group . Mean improvement in Short Form-36 physical component score was 6.6 in the rhBMP-2/ACS group and 7.5 in the ICBG group . There were 20 complications in the ICBG group and 8 complications in the rhBMP-2/ACS group ( P = 0.014 ) . Sixteen ICBG and 10 rhBMP-2/ACS patients required additional treatment for persistent back or leg symptoms . Two rhBMP-2/ACS patients had revision procedures , 1 for nonunion . Eight patients in the ICBG group had revision procedures , 5 for nonunion . Mean fusion grade on computed tomography scan was significantly ( P = 0.030 ) better in the rhBMP-2/ACS ( 4.3 ) compared with the ICBG group ( 3.8 ) . Mean cost of the initial admission was $ 36,530 in the rhBMP-2/ACS group and $ 34,235 in the iliac crest bone graft ( ICBG ) group . Total cost of care over 2 years was $ 42,574 for the ICBG group and $ 40,131 for the rhBMP-2/ACS group . Conclusion . RhBMP-2/ACS is a viable ICBG replacement in older patients in terms of safety , clinical efficacy , and cost-effectiveness BACKGROUND CONTEXT Although autogenous bone is still considered to be the gold st and ard graft material for promoting spinal fusion , other bone graft substitutes have been developed in an attempt to improve arthrodesis rates and avoid the complications associated with the procurement of autograft . The bone morphogenetic proteins ( BMPs ) represent a family of osteoinductive growth factors that are known to stimulate the osteoblastic differentiation of stem cells . Osteogenic protein-1 ( OP-1 ) Putty is a commercially available BMP preparation that is already approved for use in humans . Previous clinical studies involving patients with degenerative spondylolisthesis have reported that the efficacy and safety of OP-1 Putty is comparable to that of autograft at both 1- and 2-year follow-up . PURPOSE The purpose of this study was to evaluate the intermediate-term efficacy and safety of OP-1 Putty as an alternative to autogenous bone by comparing the 4-year radiographic , clinical , and safety data of these same patients who underwent decompression and uninstrumented fusion with either OP-1 Putty or iliac crest autograft .  STUDY DESIGN / SETTING A prospect i ve , r and omized , controlled , multicenter clinical pilot study . PATIENT SAMPLE Thirty-six patients undergoing decompressive laminectomy and single-level uninstrumented fusion for degenerative spondylolisthesis and symptomatic spinal stenosis were r and omized in a 2:1 fashion to receive either OP-1 Putty ( 24 patients ) or autogenous iliac crest bone graft ( 12 patients ) . OUTCOME MEASURES Patient-reported outcome measures consisting of Oswestry Disability Index and Medical Outcomes Study 36-Item Short Form Health Survey ( SF-36 ) scores were used to evaluate clinical efficacy . Perioperative data including operative time , estimated blood loss , and duration of hospital stay were also recorded for each surgery . Postoperatively , a neurological examination and an assessment of donor-site pain ( if applicable ) were performed at every follow-up visit . Radiographic fusion success was defined as the presence of continuous bridging bone formation between the transverse processes at the level of the spondylolisthesis with minimal motion evident on dynamic lateral x-ray films . The primary efficacy endpoint was the overall success rate , a composite measure derived from both radiographic and clinical parameters . The safety of OP-1 Putty was confirmed by comparing the nature and frequency of all adverse events and complications that were prospect ively observed in either of the groups . METHODS Thirty-six patients with degenerative spondylolisthesis and symptoms of neurogenic claudication underwent decompressive laminectomy and single-level uninstrumented fusion with either OP-1 Putty or autograft . All patients were evaluated at 6 weeks and 3 , 6 , 9 , 12 , and 24 months , after which time they were instructed to return on a yearly basis . Multiple neuroradiologists blinded to the assigned treatment review ed static and dynamic X-ray films with digital calipers to assess fusion status according to the presence of continuous bridging bone across the transverse processes as well as the amount of residual motion evident at the level of interest . Oswestry Disability Index surveys and SF-36 question naires were used to assess clinical outcomes . RESULTS At the 48-month time point , complete radiographic and clinical data were available for 22 of 36 patients ( 16 OP-1 Putty and 6 autograft ) and 25 of 36 patients ( 18 OP-1 Putty and 7 autograft ) , respectively . Radiographic evidence of a solid arthrodesis was present in 11 of 16 OP-1 Putty patients ( 68.8 % ) and 3 of 6 autograft patients ( 50 % ) . Clinical ly successful outcomes defined as at least a 20 % improvement in preoperative Oswestry scores were experienced by 14 of 19 OP-1 Putty patients ( 73.7 % ) and 4 of 7 autograft patients ( 57.1 % ) ; these clinical findings were corroborated by similar increases in SF-36 scores . The respective overall success rates of the OP-1 Putty and autograft group were 62.5 % and 33.3 % . In this study , there were no incidents of local or systemic toxicity , ectopic bone production , or other adverse events directly related to the use of OP-1 Putty . CONCLUSION Despite the challenges associated with obtaining a solid uninstrumented fusion in patients with degenerative spondylolisthesis , the rates of radiographic fusion , clinical improvement , and overall success associated with the use of OP-1 Putty were at least comparable to that of the autograft controls for at least 48 months after surgery . These results appear to vali date the short-term results previously reported for OP-1 Putty and suggest that this material may potentially represent a viable bone graft substitute for certain fusion applications Objective To determine whether a biphasic calcium phosphate ( BCP ) ceramic supplemented with fresh autologous bone marrow ( BMA ) can give rise to adequate bone to achieve a vertebral fusion mass . Material s and Methods A prospect i ve nonr and omized , radiographic study on 35 patients with posterolateral fusion using rigid transpedicular instrumentation for degenerative lumbar disease . At least 2-year follow-up . On the left side : autologous bone graft obtained from decompression . On the right side : a mixture of BCP and fresh autogenous bone marrow from the right iliac crest . Single-level fusion in 22 patients and two or more levels in 13 . Patients assessed with x-rays and computed tomography by an orthopedic surgeon and an independent radiologist .  Fusion mass was considered “ good ” when there was a continuous block of bone without radiolucent areas . No intersegmental bony bridging fusion was considered “ poor ” mass . McNemar , Fisher , and kappa tests were used for statistical analysis . Results The interobserver agreement ( κ ) had an average of 0.75 for the fusion masses . The interobserver average in the radiologic evaluation of ceramic resorption was 0.68 . No differences between smokers and nonsmokers were found . Plain radiography findings : good left fusion masses ( autologous bone ) in 31 patients and poor in 4 ; good right masses  ( BMA plus BCP ) in 31 patients and poor in 4 ( P>0.05 ) . Computed tomography evaluation : good left fusion masses in 28 patients and poor in 7 ; good right fusion masses in 31 patients and poor in 4 ( P>0.05 ) . One patient was reoperated , allowing biopsies to be performed : compact bone tissue was observed around hydroxyapatite in the right fusion mass . Conclusions The differences detected between right-side and left-side masses are not statistically significant . This indicates that , BMA and BCP , when mixed , behave like composite grafts and are able to generate sufficient bone mass for arthrodesis when a rigid instrumentation is used . However , a larger number of cases and longer follow-up are needed to generalize the indication BACKGROUND CONTEXT Spondylodesis in the operative management of lumbar spine diseases has been the subject of numerous studies over several decades . The posterolateral fusion ( PLF ) with pedicle screw fixation is a commonly used procedure . PURPOSE To determine whether the addition of bone marrow concentrate ( BMC ) to allograft bone increases fusion rate after instrumented posterior lumbar fusion . STUDY DESIGN The study was prospect i ve , r and omized , controlled , and blinded . METHODS Eighty patients with degenerative disease of the lumbar spine underwent instrumented lumbar or lumbosacral PLF ( 22 men , 58 women ; body mass index less than 35 for a good visualization of the PLF in the X-rays ) . In 40 cases , the PLF was done with spongious allograft chips alone ( Group I , age 62.7 years in average , range 47 - 77 years , level of fusion 1 - 2 ) . In another 40 cases , spongious allograft chips were mixed with BMC ( Group II , age 58.5 years in average , range 42 - 80 , level of fusion 1 - 3 ) , including the mesenchymal stem cells ( MSCs ) . Patients were scheduled for anteroposterior and lateral radiographs 12 and 24 months after the surgery and for computed tomography scanning 24 months after the surgery . Fusion status and the degree of mineralization of the fusion mass were evaluated separately by two radiologists blinded to patient group affiliation . The bony mass was judged as fused if there was uninterrupted bridging of well-mineralized bone between the transverse processes or sacrum , with trabeculation indicating bone maturation on least at one side of the spines . RESULTS In Group I at 12 months , the bone graft mass was assessed in X-rays as fused in no cases ( 0 % ) and at 24 months in four cases ( 10 % ) . In Group II , 6 cases ( 15 % ) achieved fusion at 12 months and 14 cases ( 35 % ) at 24 months . The statistically significant difference between both groups was proven for complete fusion at both 12 ( p=.041 ) and 24 months ( p=.011 ) . Computed tomography scans showed that 16 cases ( 40 % ) in Group I and 32 cases ( 80 % ) in Group II had evidence of at least unilateral continuous bridging bone between neighboring vertebrae at 24 months ( p<.05 ) . CONCLUSIONS We have confirmed the hypothesis that the autologous BMC together with the allograft is a better alternative for PLF than the allograft alone . The use of autologous MSCs in form of BMC in combination with allograft is an effective option to enhance the PLF healing BACKGROUND CONTEXT Reported fusion rates for spine fusions using iliac crest bone graft ( ICBG ) vary between 40 % and 100 % because of different fusion techniques , patient comorbidity , diagnosis and assessment criteria . PURPOSE We report two-year results of  single-level instrumented posterolateral fusions  evaluated with radiographs , fine-cut computed tomography ( CT ) scans with reconstructions and outcome measures . STUDY DESIGN / SETTING : Retrospective analysis of data from a prospect i ve multicenter r and omized clinical controlled trial . PATIENT SAMPLE Patients with various degenerative diagnoses enrolled in the control arm of a Food and Drug Administration ( FDA ) -regulated , multicenter trial of single-level decompression and posterolateral fusion for degenerative lumbar disease . OUTCOME MEASURES Short Form-36 ( SF-36 ) , Oswestry Disability Index ( ODI ) , Numeric Rating Scales ( 0 - 20 ) for back , leg , and graft site pain , CT scans , anteroposterior and lateral flexion/extension radiographs . METHODS Patients enrolled in an FDA -regulated , multicenter trial at 29 sites with degenerative lumbar disease treated with single-level instrumented posterolateral fusion with ICBG were included in the analysis . Demographic and surgical data were collected . Clinical outcomes were followed using st and ard metrics . Fusion was assessed by independent radiologists at 6 , 12 , and 24 months postoperatively . Two fusion criteria were compared : anteroposterior and flexion/extension radiographs to assess motion and bridging bone , with CT scans as needed to confirm bridging bone ; and CT scan assessment for bridging bone only . RESULTS One hundred ninety-four of 224 subjects ( 86.6 % ) completed the study . The mean operative time was 2.9 hours with a blood loss of 448.6 mL. The average graft volume was 36.3 mL. There were 21 ( 9.4 % ) wound infections , 18 ( 8.0 % ) incidental durotomies , 3 ( 1.3 % ) implant displacements , 2 ( 0.9 % ) malpositioned implants , and 17 ( 7.6 % ) graft-related complications . Twenty-seven patients ( 13.9 % ) required reoperation , the majority for nonunions . Fusion rates based on radiographs with selective CTs at 6 , 12 , and 24 months were 65.3 % , 82.5 % , and 89.3 % , respectively . Fusion rates based on bridging bone on CT scans were 56.1 % , 71.5 % , 83.9 % , respectively . Two-year improvement for all outcome measures was significant (p<.001)-ODI 25.3 , SF-36 Physical Component Score ( PCS ) 12.2 , back pain 7.9 , and leg pain 7.1 . Two years postoperatively , 60 % of patients complained of graft site pain ( mean pain score=8.5 ) . CONCLUSION In a large series of patients who had primary single-level instrumented posterolateral fusion with ICBG , evidence of bridging bone on fine-cut CT scans improved with time to 83.9 % at 24 months . Significant improvement from baseline was noted in all clinical outcome measures at all time intervals with 75 % achieving minimum clinical ly important difference ( MCID ) for ODI and 66 % achieving MCID for SF-36 PCS Study Design . Prospect i ve clinical study . Objective . Compare fusion rates between recombinant human bone morphogenetic protein-2 ( rhBMP-2 ) and iliac crest bone graft ( ICBG ) with rhBMP-2 and local bone graft ( LBG ) ( ±bone graft extenders ) in posterolateral fusion . Summary of Background Data . Previous reports have shown higher fusion rates when adding rhBMP-2 to ICBG in lumbar posterolateral fusion , compared with ICBG alone . We compared the fusion success rates between rhBMP-2 delivered with ICBG versus that with LBG . Methods . Fusion rates were compared in patients with degenerative spondylolisthesis ( 1–2 levels ) with accompanying lumbar stenosis .  RhBMP-2 ( INFUSE , Medtronic ) was delivered on an absorbable collagen sponge ( 6 mg/side at 1.5 mg/mL ) with ICBG alone or with LBG wrapped inside the sponge . Thin slice computed tomographic scans were assessed at 6 , 12 , and 24 months . Results . In a consecutive series , 16 patients ( 30 levels ) received ICBG with rhBMP-2 and 35 patients ( 49 levels ) received LBG with rhBMP-2 . For the ICBG cohort , 80.0 % , 93.4 % , 96.7 % of levels were fused at 6 , 12 , and 24 months . In contrast , for the local bone with rhBMP-2 cohort , 87.7 % , 98.0 % , and 98.0 % were fused at 6 , 12 , and 24 months . There was no statistically significant difference in fusion success rates between the 2 groups at any time point . As for fusion quality , the fusion mass showed superior quality in ICBG group than in the local bone group at each time point . Conclusion . This study vali date s the high fusion success rates previously reported by adding rhBMP-2 to ICBG and shows that local bone may be safely substituted for ICBG in 1- to 2-level posterolateral fusion . The fusion rates were comparable . The avoidance of ICBG harvest has implication s for operative time , blood loss , and morbidity . Lastly , this is the first study that directly compares the fusion success rate and quality using local bone with rhBMP-2 versus ICBG with rhBMP-2 at various times . Level of Evidence : Study Design / Setting . Retrospective review of a consecutive , nonr and omized series operated on by 2 surgeons . Objective . To evaluate the clinical and radiographic effectiveness of a silicated hydroxyapatite ceramic as a bone graft substitute in a series of patients undergoing posterolateral instrumented lumbar fusion . Summary of Background Data . Newer-generation synthetic ceramics have been refined to maximize their host-graft interaction and stimulation of new tissue formation , including silicate-substitution . Methods . An independent radiologist interpreted the computed tomography images at 6 , 12 , and 24 months after surgery . Forty-two patients with 1- or 2-level lumbar degenerative disorders underwent posterior laminectomy ( when indicated ) and posterolateral fusion with instrumentation .  Surgical levels included 15 patients who underwent 2-level and 27 single-level fusion procedures ( 57 levels operated on in total ) . Results . The average back pain scores improved from 5.6 ± 2.5 preoperative to 2.1 ± 2.5 at follow-up ( P < 0.05 ) . Similar results were seen with leg pain improvement from 5.8 ± 2.5 to 1.4 ± 1.9 ( P < 0.05 ) . At 6 months , 35 % of levels revealed fusion , which increased to 76.2 % and 76.5 % at 12 and 24 months , respectively . No evidence of ectopic bone formation or osteolysis was noted . Conclusion . In this study , a silicated calcium phosphate-based ceramic has been shown to be effective as a graft substitute and eliminate the need for autogenous iliac crest bone graft . The results confirm radiographic healing in posterolateral instrumented lumbar fusion at 24-months follow-up . The clinical outcomes also substantiate significant pain improvement consistent with published data in the literature compared with other bone graft alternatives Study Design . A prospect i ve study . Objectives . To compare the efficacy of calcium sulfate pellets plus laminectomy bone chips with a fresh autologous iliac bone graft for short-segment lumbar fusion . Summary of Background Data . Bone graft substitute material can be used to exp and an existing quantity of available laminectomy bone chips . Methods . Seventy-four patients underwent surgery for instrumented one- or two-segment fusion with decompression .  Autologous iliac crest bone graft was placed in one posterolateral gutter , while on the other side , an equal quantity of autogenous laminectomy bone supplemented with calcium sulfate was placed .  Radiographic assessment included radiographs alone ; this was performed every 3 months ( 3 months to 12 months ) , then annually . The status of fusion and the relative size of the fusion bone mass on either side of the vertebra were compared . Results . Using iliac crest bone graft ( control side ) versus autograft laminectomy bone with calcium sulfate ( test side ) , there was no significant difference between the fusion rate and sizes of the fusion bone mass ( P > 0.05 ) . Follow-up periods ranged from 30 months to 34 months , averaging 32.5 months . For the 39 patients who received single-segment fusion , 34 patients ( 87.2 % ) exhibited bone fusion on the test side , and 35 patients ( 89.7 % ) had evidence of fusion on the control side . For the 35 patients who received two-segment fusion , 29 patients ( 82.9 % ) exhibited bone fusion on the test side and 30 patients ( 85.7 % ) demonstrated complete fusion on the control side . Conclusions . The fusion rate and fusion size between the two groups are similar . Calcium sulfate pellets may play a role as a bone graft extender in short-segment spinal fusion Study Design . R and omized efficacy trial comparing two types of noninstrumented posterolateral fusion between L5 and S1 in patients with L5 spondylolysis and vertebral slip less than 50 % , as evaluated by radiostereometric analysis . Objective . To determine whether osteogenic protein-1 ( BMP-7 ) in the OP-1 Implant yields better stabilizing bony fusion than autograft bone . Summary of Background Data . Animal studies of osteoinductive proteins in noninstrumented posterolateral fusions have shown high fusion rates . No similar conclusive study on humans has been performed . Methods . For this study , 20 patients were r and omized to fusion with either OP-1 Implant or autograft bone from the iliac crest , 10 in each group . The patients were instructed to keep the trunk straight for 5 months after surgery with the aid of a soft lumbar brace . At surgery 0.8-mm metallic markers were positioned in L5 and the sacrum , enabling radiostereometric follow-up analysis during 1 year . The three-dimensional vertebral movements , as measured by radiostereometric analysis induced by positional change from supine posture to st and ing and sitting , were calculated with an accuracy of 0.5 to 0.7 mm and 0.5 ° to 2.0 ° . Conventional radiography was added . Results . No significant difference was noted between the radiostereometric and radiographic results of fusion with the OP-1 Implant and fusion with autograft bone . There was a significant relation between reduced vertebral movements and better bone formation . No adverse effects of the OP-1 Implant occurred . Persistent minor pain at the iliac crest was noticed in one patient . Conclusions . There was no significant difference between the two fusion versions . Thus , the OP-1 Implant did not yield better stabilizing bony fusion than autograft bone BACKGROUND CONTEXT Recombinant human bone morphogenetic protein-2 ( rhBMP-2 ) is an osteoinductive protein approved for use in the anterior lumbar interspace . High fusion rates with rhBMP-2 have been reported with threaded interbody allograft dowels . There may be a clinical benefit for the patient by adding rhBMP-2 to the allograft . PURPOSE To compare the fusion rates and clinical outcomes of patients treated with allograft interbody fusions  with and without the addition of rhBMP-2 . STUDY DESIGN Prospect i ve consecutive patient enrollment with minimum 24-month follow-up . PATIENT SAMPLE Seventy-five patients with lumbar interbody fusions at 1 - 3 spinal segments . OUTCOMES MEASURES Clinical : Numerical Rating Scale ( NRS ) and Oswestry Disability Index ( ODI ) . Radiographic : X-ray and computed tomographic scan analysis using the Molinari-Bridwell fusion scale . METHODS Seventy-five patients scheduled for lumbar fusion were enrolled sequentially . Group 1 : 30 patients had anterior interbody allografts alone . Group 2 : 45 patients had anterior interbody allograft filled with rhBMP-2 . All cases had posterior pedicle screw instrumentation . A total of 165 surgical levels ( 62 allograft alone/103 allograft+BMP ) were included . Fusion data and clinical outcomes were collected for a minimum of 2 years after surgery . RESULTS Statistically higher fusion rates were observed in the patients with BMP at all time points compared with allograft alone . Group 2 ( + BMP ) fusion rates were 94 % , 100 % , and 100 % at 6 , 12 , and 24 months after surgery . Group 1 ( -BMP )  fusion rates were 66 % , 84 % , and 89 % at the same time intervals . Clinical outcomes were significantly improved in Group 2 compared with Group 1 at 6 months . There were no revisions ( 0 % ) in the BMP group and 4 revision fusion surgeries ( 13 % ) in the allograft group . No untoward effects were attributable to the rhBMP-2 . CONCLUSIONS Our study confirms the efficacy of an innovative lumbar fusion technique : an interbody femoral ring allograft , combined with an osteoinductive stimulant ( rhBMP-2 ) , protected by pedicle screws . This combination of a structural interbody allograft with rhBMP-2 eliminates the insult of iliac crest harvest , allows for reliable radiographic analysis , and results in successful fusion formation in 100 % of the cases in this study BACKGROUND Recombinant human bone morphogenetic protein-2 ( rhBMP-2 ) on an absorbable collagen sponge has been shown to be a safe and effective replacement for iliac crest bone graft when used with a threaded fusion device in anterior lumbar interbody arthrodesis . Use of rhBMP-2 on an absorbable collagen sponge in posterolateral lumbar arthrodesis requires the addition of a bulking agent to provide resistance against compression and to serve as an osteoconductive scaffold for new bone formation . METHODS We performed a prospect i ve , r and omized , multicenter pilot study to investigate the use of rhBMP-2 on an absorbable collagen sponge combined with a ceramic-granule bulking agent as a replacement for autogenous iliac crest bone graft in single-level posterolateral lumbar arthrodesis with instrumentation . The investigational group ( twenty-five patients ) was treated with a 1.5 mg/mL solution of rhBMP-2 on two strips of absorbable collagen sponge ( total dose of rhBMP-2 , 12 mg ) combined with 10 cm(3 ) of ceramic granules .  The control group ( twenty-one patients ) received iliac crest bone graft . Clinical outcomes were assessed with use of well-established instruments . Radiographs were review ed to assess consolidation of fusion . RESULTS Eighty-eight percent ( twenty-two ) of the twenty-five patients in the investigational group and 86 % ( eighteen ) of the twenty-one patients in the control group were considered to have completed the twenty-four-month follow-up . At all follow-up intervals , there were significant improvements in the clinical outcome measures , including the Oswestry Disability Index ( ODI ) scores , Short Form-36 scores , and back and leg pain scores , in both groups . At twenty-four months , the improvement in the mean ODI score , as compared with the preoperative score , was 28.2 points in the investigational group and 23.0 points in the control group . By twenty-four months , 95 % ( eighteen ) of nineteen patients in the investigational group compared with 70 % ( fourteen ) of twenty in the control group had a radiographically documented fusion . The overall success rate was 81 % ( seventeen of twenty-one ) in the investigational group and 55 % ( eleven of twenty ) in the control group ( p = 0.345 ) . CONCLUSIONS Compared with an iliac crest bone graft , the combination of an absorbable collagen sponge soaked with rhBMP-2 and ceramic granules result ed in trends toward improvements in clinical outcomes and toward a higher rate of radiographic fusion . This combination of an osteoinductive agent with an osteoconductive matrix may be an effective replacement for autograft in single-level posterolateral lumbar arthrodeses with instrumentation Study Design . Prospect i ve , r and omized , unblinded study of iliac crest bone graft ( ICBG ) versus recombinant human bone morphogenetic protein-2/compression resistant matrix (rhBMP-2/CRM)in a posterolateral instrumented fusion procedure . Objectives . Document initial radiographic characteristics , based on computed tomography , with rhBMP-2/CRM for posterolateral fusion at 6 and 12-month intervals . Summary of Background Data . As the acceptance of INFUSE bone graft as an ICBG replacement becomes more widespread , surgeons have begun to study applications for rhBMP-2 in posterior spinal fusion . Pre clinical studies have examined variables including carrier composition , rhBMP-2 concentration , and rhBMP-2 dose . Pilot studies have been performed with encouraging initial results . Methods . Patients with single level lumbar degenerative disease were enrolled in a r and omized study of ICBG versus rhBMP-2/CRM in a posterolateral instrumented fusion procedure . Computed tomography scans at 6 and 12 months were grade d as demonstrating no fusion ( grade 1 ) , partial or limited unilateral fusion ( grade 2 ) , partial or limited bilateral fusion ( grade 3 ) , solid unilateral fusion ( grade 4 ) , or solid bilateral fusion ( grade 5 ) . Results . At our institution , 74 patients ( 38 rhBMP-2/CRM  , 36 ICBG ) reached minimum 1-year follow-up and were included in this analysis . Mean fusion grade ( scale1–5 ) at 6 months after surgery was 4.35 in the rhBMP-2/CRM group versus 3.09 in the ICBG group ( P < 0.0001 ) . At 1 year after surgery mean fusion grade was 4.62 in the rhBMP-2/CRM group versus 3.77 in the ICBG group ( P < 0.0023 ) . Conclusions . These early results are encouraging and suggest a more rapid incorporation and development of the fusion mass with rhBMP-2/CRM than iliac crest autograft in a single level posterior instrumented fusion Study Design . R and omized clinical trial . Objective . To perform a cost-utility analysis using actual cost data from a r and omized clinical trial of patients over 60 years old who underwent posterolateral fusion using either rhBMP-2/ACS or iliac crest bone graft ( ICBG ) .  Summary Background Data . Bone morphogenetic protein has been shown to be an effective bone graft substitute for spine fusion . However , a clinical trial-based economic analysis of rhBMP-2/ACS compared with iliac crest bone graft has not been done . Methods . Patients over 60 years old requiring decompression and posterolateral fusion were r and omized to rhBMP-2/ACS ( n = 50 ) or ICBG ( n = 52 ) . A dedicated hospital coder and research nurse tracked each patient to determine direct costs of inpatient care and all postoperative healthcare encounters up to 2 years after surgery . Preoperative and 2-year-postoperative SF-6D utility scores for each patient were determined . A decision tree was created , which included the probability of complications , need for additional treatments and revision surgery ; and the costs associated with initial surgery and treatment for complications and additional treatment for continued spine symptoms ; and utility scores . Results . The mean total 2-year cost for care ( excluding complication and additional spine treatment costs ) was $ 34,235 in the ICBG group and $ 36,530 in the rhBMP-2/ACS group . For the entire group , the mean cost to treat a major complication was $ 10,888 , the cost of revision surgery for nonunion was $ 46,852 , and additional treatment for spine-related events was $ 5892 . In the ICBG group , 8 patients had complications ; 20 had additional interventions , 5 of whom required revision for nonunion . In the rhBMP-2/ACS group , 6 patients had complications , 10 had additional interventions , and 1 required revision for nonunion . The cost of using rhBMP-2/ACS was $ 39,967 with a 0.11 mean improvement in SF-6D ; and for ICBG the cost was $ 42,286 with a mean improvement of 0.10 in SF-6D . Conclusion . There are more complications , increased need for additional treatment and revision surgery in patients over 60 years old receiving  ICBG  compared with rhBMP-2/ACS . This may account for higher costs and lower improvements in utility seen in patients receiving ICBG compared with rhBMP-2/ACS in this study population BACKGROUND CONTEXT Interbody spinal fusion relies on the use of external fixation and the placement of a fusion cage filled with graft material s ( scaffolds ) without regard for their mechanical performance . Stability at the fusion site is instead reliant on fixation hardware combined with a selected cage . Ideally , scaffolds placed into the cage should both support the formation of new bone and contribute to the mechanical stability at the fusion site . PURPOSE We recently developed a scaffold consisting of silane-modified PCL-TCP ( PCL-siTCP ) with mechanical properties that can withst and the higher loads generated in the spine . To ensure the scaffold more closely mimicked the bone matrix , we incorporated collagen ( Col ) and a heparan sulfate glycosaminoglycan sugar ( HS3 ) with increased affinity for heparin-binding proteins such as bone morphogenetic protein-2 ( BMP-2 ) . The osteostimulatory characteristic of this novel device delivering exogenous BMP2 was assessed in vitro and in vivo as a prelude to future spinal fusion studies with this device . STUDY DESIGN / SETTING A combination of cell-free assays ( BMP2 release ) , progenitor cell-based assays ( BMP2 bioactivity , cell proliferation and differentiation ) , and rodent ectopic bone formation assays was used to assess the osteostimulatory characteristics of the PCL-siTCP-based scaffolds . MATERIAL S AND METHODS Freshly prepared rat mesenchymal stem cells were used to determine reparative cell proliferation and differentiation on the PCL-siTCP-based scaffolds over a 28-day period in vitro . The bioactivity of BMP2 released from the scaffolds was assessed on progenitor cells over a 28-day period using ALP activity assays and release kinetics as determined by enzyme-linked immunosorbent assay . For ectopic bone formation , intramuscular placement of scaffolds into Sprague Dawley rats ( female , 4 weeks old , 120 - 150 g ) was achieved in five animals , each receiving four treatments r and omized for location along the limb . The four groups tested were ( 1 ) PCL-siTCP/Col ( 5-mm diameter × 1-mm thickness ) , PCL-siTCP/Col/BMP2 ( 5 µg ) , ( 3 ) PCL-siTCP/Col/HS3 ( 25 µg ) , and ( 4 ) PCL-siTCP/Col/HS3/BMP2 ( 25 and 5 µg , respectively ) . Bone formation was evaluated at 8 weeks post implantation by microcomputed tomography ( µCT ) and histology . RESULTS Progenitor cell-based assays ( proliferation , mRNA transcripts , and ALP activity ) confirmed that BMP2 released from PCL-siTCP/Col/HS3 scaffolds increased ALP expression and mRNA levels of the osteogenic biomarkers Runx2 , Col1a2 , ALP , and bone gla protein-osteocalcin compared with devices without HS3 . When the PCL-siTCP/Col/HS3/BMP2 scaffolds were implanted into rat hamstring muscle , increased bone formation ( as determined by two-dimensional and three-dimensional µCTs and histologic analyses ) was observed compared with scaffolds lacking BMP2 . More consistent increases in the amount of ectopic bone were observed for the PCL-siTCP/Col/HS3/BMP2 implants compared with PCL-siTCP/Col/BMP2 . Also , increased mineralizing tissue within the pores of the scaffold was seen with modified-tetrachrome histology , a result confirmed by µCT , and a modest but detectable increase in both the number and the thickness of ectopic bone structures were observed with the PCL-siTCP/Col/HS3/BMP2 implants . CONCLUSIONS The combination of PCL-siTCP/Col/HS3/BMP2 thus represents a promising avenue for further development as a bone graft alternative for spinal fusion surgery OBJECT The objective of this study was to examine the efficacy and safety of Healos graft carrier with bone marrow aspirate and local autograft compared with the results of allograft in patients with lumbar degenerative scoliosis undergoing posterolateral fusion . METHODS Twenty-eight patients with degenerative scoliosis underwent posterolateral instrumented fusion and decompression . Patients were grouped according to the graft used . Group A consisted of 12 cases in which the authors used a Healos graft carrier , bone marrow aspirate , and local autograft , and Group B consisted of 16 cases in which the authors used cancellous allograft and local autograft . Patients were followed for a minimum of 2 years postoperatively in terms of pain ( visual analog scale ) , function ( Oswestry Disability Index ) , curve magnitude ( Cobb angle ) , and fusion status ( plain and dynamic radiographs ) . The 2 groups did not differ statistically significantly ( p > 0.05 ) in age , sex , smoking habits , magnitude of preoperative visual analog scale score , Oswestry Disability Index score , Cobb angle , or number of levels requiring decompression and fusion . RESULTS The groups had similar ( p > 0.05 ) results in terms of pain , function , curve progression , and fusion rates at the 2-year follow-up examination . Radiographic fusion was achieved in all but 2 cases , 1 in each group , in which the patients were asymptomatic . Patients in the allograft group ( Group B ) showed evidence of fusion earlier than in the Healos group ( p < 0.05 ) . No toxicity from  Healos graft was recorded . CONCLUSIONS The combination of Healos hydroxyapatite sponge and bone marrow aspirate plus local allograft had significantly slower fusion rates but equal clinical outcomes compared with cancellous allograft plus local autograft when used for posterolateral fusion in patients with degenerative lumbar scoliosis Purpose Addition of bone marrow to the bone graft in the postero-lateral lumbar arthrodesis is a widely used technique . Bone marrow brings stem cells and growth factors contained in the platelets , favorable for bone growth . Adjunction of concentrated bone marrow should create better conditions and may increase bone growth . Methods Simple blind r and omized clinical , prospect i ve , monocentric trial was conducted . Fifteen patients underwent lumbar arthrodesis .  During surgery , a fraction of the bone marrow harvested was centrifuged . One side received this concentrate with autologous bone and ceramics ; the other side received the same graft with unconcentrated bone marrow . A quantitative study , realised with a volume calculating software on CT-scan images , determined the cortical bone volume in the graft post-operatively and at 3 months . The osteoprogenitor cells , nucleated cells and platelet concentrations were determined . Results The biological study found an average concentration of six times for the nucleated cells , 3.5 times for the platelets and 2.2 times for the osteoprogenitor cells . The comparison of the mean cortical bone volumes post-operatively and at 3 months was not significantly different . Conclusions Despite the concentration obtained , there was no increase of bone growth by adding concentrated bone marrow . However , the number of stem cells in bone marrow was low and maybe a stronger concentration is needed to obtain a difference . The 3D reconstruction of the graft and the analysis of the graft ’s volume using a novel software was efficient according to the similarity of the graft ’s volume post-operatively in all patients Introduction This study determines whether recombinant human bone morphogenetic protein-2 ( rhBMP-2 ) ( 12 mg at the rate of 1.5 mg/mL ) delivered on an absorbable collagen sponge with an added bulking agent can increase posterolateral lumbar spine fusion success rates and decrease time for fusion with autogenous bone grafts . Method A prospect i ve , single institution , clinical case-matched , radiographic , cohort study was undertaken . A total of 52 patients underwent posterolateral lumbar arthrodesis with pedicle screw instrumentation .  The experimental group ( n=41 ) underwent placement of Iliac crest bone graft ( ICBG ) with InFUSE ( 12 mg/level at the rate of 1.5 mg/mL ) . The control group ( n=11 ) consisted of sex-matched patients , consecutively collected over the same time period with an instrumented posterolateral arthrodesis and ICBG placed in the intertransverse space . Outcome Measures Thin-cut ( 2 mm ) axial , coronal , and sagittal reconstructions were blindly evaluated for evidence of bridging bone and cortication of the fusion mass by 3 separate review ers . Fusions were grade d and an overall score was given to the quality of the fusion mass . Results Fifty patients ( ICBG alone n=11 ; ICBG/rhBMP-2 n=39 ) were available for CT evaluation at 2-year follow-up . An overall 97 % ( 68/70 levels ; Definite+Probably Fused ) fusion rate in the rhBMP-2 group was achieved as compared to the 77 % fusion rate ( 17/22 levels ) in the ICBG alone group ( P<0.05 ) . In the rhBMP-2 group , 92 % of the patients ( 36/39 patients ) received an overall excellent subjective fusion rating as compared to 27 % ( 3/11 ) in the control group ( P<0.05 ) . There was no computed tomographic evidence of soft-tissue ossification , dural ossification , or laminar bone regrowth in any patient . Conclusions The adjunctive use of rhBMP-2 and ICBG seems to be safe and results in significantly larger and more consistent posterolateral fusion masses Introduction The aim of the study was to analyze if the adding of autologous platelet concentrate ( APC ) to a mixture of local autograft plus tricalcium phosphate and hidroxiapatite ( TCP/HA ) would improve the fusion rate in posterolateral lumbar fusion . Material s and methods A prospect i ve , controlled , blinded , non-r and omized clinical trial was carried out in 107 patients affected by degenerative lumbar pathology . The study group consisted of 67 patients , in which  autologous platelet concentration was added to a mixture of autologous local bone graft and TCP/HA . A control group of 40 patients with same pathology and surgical technique but without APC addition  was used to compare the fusion mass obtained . By means of plain X-rays , a blinded evaluation of the intertransverse fusion mass quality at twelve and twenty-four months was made according to type A ( bilateral uniform mass ) , type B ( unilateral uniform mass ) and type C ( irregular or lack bilateral mass ) . Patients with type C were regarded as pseudoarthrosis . Results In the study group 17 patients had lack or irregular fusion mass ( 25.4 % ) versus three patients in the control group ( 7.5 % ) , which was statistically significant . Conclusions This study shows that the adding of autologous platelet concentration to a mixture of autologous bone graft plus TCP/HA has decreased our rates of posterolateral lumbar fusion Study Design . A prospect i ve , r and omized clinical study comparing & bgr;-tricalcium phosphate ( & bgr;-TCP ) with autograft bone graft with follow-up of 3 years . Objective . To determine the efficacy of & bgr;-TCP as a bone graft substitute combined with local autograft obtained from decompression compared with the use of autologous iliac crest bone graft in single-level instrumented posterolateral lumbar fusion . Summary of Background Data . A variety of bone graft substitutes have been used in posterolateral lumbar fusion with different efficacy reported , but no controlled study was conducted on the clinical performance of & bgr;-TCP in instrumented posterolateral lumbar fusion . Methods . Sixty-two patients with symptomatic degenerative lumbar spinal stenosis were treated with single-level instrumented posterolateral lumbar fusion . They were r and omly assigned to fusion with & bgr;-TCP combined with local bone obtained from the decompression ( group A , n = 32 ) or autogenous iliac crest bone graft plus decompression bone ( group B , n = 30 ) . The patients were observed up for 3 years after surgery . The results were assessed clinical ly and radiographically . Results . There were no significant differences in recovery rate of Japanese Orthopedic Association score and SF-36 score at all time intervals . Successful radiographic fusion was documented in all patients in both treatment groups . All patients in group B , however , complained bone graft donor site pain although significant improvement of pain was observed during the follow-up . Conclusion . Instrumented posterolateral fusion with & bgr;-TCP combined with local autograft results in the same radiographic fusion rates and similar improvement of clinical outcomes and life quality compared with autograft alone . The authors therefore recommend the use of & bgr;-TCP as bone graft substitute for instrumented posterolateral fusion of lumbar spine to eliminate the need of bone grafting harvesting from the ilium Study Design . Retrospective review of prospect ively collected data , as part of an IRB-approved , FDA -regulated , r and omized , nonblinded IDE trial of rhBMP-2 matrix for lumbar spinal fusion . Objectives . The purpose of this study is to examine the influence of smoking on fusion rate and outcome in a large series of patients treated with an rhBMP-2 matrix ( AMPLIFY ) or iliac crest bone graft as part of a r and omized IDE trial for single-level lumbar fusion . Summary of Background Data . Pre clinical studies suggest that bone morphogenetic proteins ( BMPs ) are able to reverse the negative influence of nicotine on fusion healing in animal models . It remains unclear if a similar benefit will be seen in humans , and if so , what formulation and amount of BMP will be required to achieve that improvement . Methods . We review ed the clinical and radiographic records of 148 patients who underwent single-level instrumented lumbar fusion at three spine centers as part of an ongoing FDA -regulated IDE trial . Clinical outcome measures included Oswestry Disability Index , SF-36 , back , and leg pain scores . Radiographic measures were plain radiographs with flexion-extension views and fine cut computed tomography scans with sagittal and coronal reconstruction . Fusion success was determined by independent radiologist readings . Results . At 2 years postoperatively , solid fusion was demonstrated in all 55 nonsmokers in the rhBMP-2 group ( 100 % ) . Successful fusion was seen in 20 of 21 smokers in the rhBMP-2 group ( 95.2 % ) . Fusion was achieved in 48 of 51 nonsmokers in the iliac crest bone graft ( ICBG ) group ( 94.1 % ) , but only 16 of 21 smokers ( 76.2 % ) in the ICBG group . Conclusions . The results of this study suggest that rhBMP-2 may enhance fusion rate in cigarette smokers undergoing single-level instrumented posterolateral lumbar fusion . Despite the improvement in fusion rate with rhBMP-2 , clinical outcomes measures were still adversely affected in smokers OBJECTIVE To compare the efficacy of calcium sulfate pellets plus bone obtained from decompression with fresh autologous iliac crest bone in lumbar and lumbosacral spinal fusion with decompression . DESIGN A prospect i ve r and omized clinical trial . SETTING Four tertiary care centres in Halifax , NS . PATIENTS All were consenting , skeletally mature and suffering from degenerative disc disease or spondylolisthesis . The first 40 patients from a single test centre are reported ; 32 of these had completed 1-year follow-up . INTERVENTIONS Posterolateral lumbar or lumbosacral spinal fusion with spinal canal decompression and r and omized placement of test material ( decompression bone plus an equal volume of calcium sulfate pellets ) on one side and control material ( autologous posterior iliac crest bone of equal volume to the test material ) on the contralateral side , which allowed subjects to act as their own control . OUTCOME MEASURES Assessment of bone formation by radiographic evaluation at 6 and 12 months after fusion by an independent musculoskeletal radiologist blinded to the placement of test material . RESULTS At 6 and 12 months after fusion , 78 % and 88 % of patients , respectively , showed bone formation at the test site that was 75 % to 100 % of , equal to or more than that at the control site . Increases in bone formation at 6 and 12 months were almost identical at both sites . Smoking status , patient gender or age , instrumentation used and volume of graft used were not predictive of outcome . CONCLUSIONS Calcium sulfate pellets plus decompression bone provided bone formation equivalent to autologous iliac crest bone in a majority of patients . Calcium sulfate pellets plus decompression bone may provide a viable alternative to autologous iliac crest as a graft material for spinal fusion Study Design . This is a prospect i ve , r and omized study comparing iliac crest bone graft to bone morphogenetic protein (BMP)/compression resistant matrix in instrumented posterolateral fusions for single-level lumbar degenerative disease . A higher recombinant human bone morphogenetic protein (rhBMP)-2 dose and a carrier specific for posterior spine applications were used . Objectives . As part of a Food and Drug Administration IDE study , clinical outcomes and fusion rates of single-level instrumented posterolateral fusions using iliac crest bone graft or BMP/compression resistant matrix were evaluated . Summary of Background Data . Although iliac crest graft is the gold st and ard for lumbar fusion , alternatives to obviate the morbidity of graft harvest have become available . R and omized clinical trials have demonstrated equivalent fusion rates and clinical outcomes with rhBMP-2 and a collagen sponge versus autograft in anterior lumbar fusions . A human pilot study using rhBMP-2 with biphasic calcium phosphate demonstrated similar results for posterolateral fusions . Methods . Demographic and perioperative data , Short Form 36 , Oswestry Low Back Pain Disability Index , and leg and back pain scores were determined before surgery , and 1.5 , 3 , 6 , 12 , and 24 months after surgery . Independent neuroradiologists ’ evaluation of fine-cut computerized tomography scans with reconstructions were obtained at 6 , 12 , and 24 months . Results . There were 98 subjects , 45 in the iliac crest bone graft group and 53 in the BMP/compression resistant matrix group . There were no significant differences for age , weight , sex , smoking , or previous surgery between the groups . The average operative time ( 2.9 hours ) and blood loss ( 465 cc ) in the iliac crest bone graft group was greater than in the BMP/compression resistant matrix group ( 2.4 hours and 273 cc ) . There were no significant differences in any outcome measure at all time intervals . The fusion rate was lower in the iliac crest bone graft group ( 73 % ) than in the BMP/compression resistant matrix group ( 88 % ) at P = 0.051 . Conclusion . There was significant improvement of Short Form 36 ( physical component score and pain ) , Oswestry Low Back Pain Disability Index , and leg and back pain scores in both groups over all time intervals . Surgical time and blood loss were significantly less in the BMP/compression resistant matrix group . The fusion rate in the BMP/compression resistant matrix group was significantly higher than the iliac crest bone graft group A prospect i ve long-term follow-up study of bioactive glass (BAG)-S53P4 and autogenous bone ( AB ) used as bone graft substitutes for posterolateral spondylodesis in treatment of degenerative spondylolisthesis during 1996 to 1998 was conducted . The surgical procedure was a st and ardized instrumented posterolateral fusion that used USS/VAS . BAG was implanted on the left side of the fusion bed and AB on the right side . The operative outcome was evaluated on x-rays and computed tomography scans , and a clinical examination was also performed . Seventeen patients ( 12 women , 5 men ) participated in the 11-year follow-up . The mean Oswestry Disability Index score at the follow-up was 21 ( range 0 to 52 ) , compared with 49 ( range 32 to 64 ) at the preoperative time . A solid bony fusion was seen on computed tomography scans on the AB side in all patients and on the BAG side in 12 patients . The fusion rate of all fusion sites ( n=41 ) for BAG as a bone substitute was 88 % at the L4/5 level and 88 % at the L5/S1 level . The use of BAG as a bone graft extender can be considered as a good alternative in spinal surgery in the future Study Design . Multicenter r and omized controlled trial . Objective . To evaluate the effect of recombinant human bone morphogenetic protein ( rhBMP-2 ) on radiographical fusion rate and clinical outcome for surgical lumbar arthrodesis compared with iliac crest autograft . Summary of Background Data . In many types of spinal surgery , radiographical fusion is a primary outcome equally important to clinical improvement , ensuring long-term stability and axial support . Biologic induction of bone growth has become a commonly used adjunct in obtaining this objective . We undertook this study to objectify the efficacy of rhBMP-2 compared with traditional iliac crest autograft in instrumented posterolateral lumbar fusion . Methods . Patients undergoing 1- or 2-level instrumented posterolateral lumbar fusion were r and omized to receive either autograft or rhBMP-2 for their fusion construct . Clinical and radiographical outcome measures were followed for 2 to 4 years postoperatively . Results . One hundred ninety seven patients were successfully r and omized among the 8 participating institutions .  Adverse events attributable to the study drug were not significantly different compared with controls . However , the control group experienced significantly more graft-site complications as might be expected . 36-Item Short Form Health Survey , Oswestry Disability Index , and leg/back pain scores were comparable between the 2 groups . After 4 years of follow-up , radiographical fusion rates remained significantly higher in patients treated with rhBMP-2 ( 94 % ) than those who received autograft ( 69 % ) ( P = 0.007 ) . Conclusion . The use of rhBMP-2 for instrumented posterolateral lumbar surgery significantly improves the chances of radiographical fusion compared with the use of autograft . However , there is no associated improvement in clinical outcome within a 4-year follow-up period . These results suggest that use of rhBMP-2 should be considered in cases where lumbar arthrodesis is of primary concern . Level of Evidence : This prospect i ve longitudinal r and omized clinical and radiological study compared the evolution of instrumented posterolateral lumbar and lumbosacral fusion using either coralline hydroxyapatite ( CH ) , or iliac bone graft ( IBG ) or both in three comparable groups , A , B and C , which included 19 , 18 and 20 patients , respectively , who suffered from symptomatic degenerative lumbar spinal stenosis and underwent decompression and fusion . The patients were divided r and omly according to the graft used and the side that it was applied . The spines of group A received autologous IBG bilaterally ; group B , IBG on the left side and hydroxyapatite mixed with local bone and bone marrow on the right side ; group C , hydroxyapatite mixed with local bone and bone marrow bilaterally .  The age of the patients in the groups A , B and C was 61±11 years , 64±8 years and 58±8 years , respectively .  The SF-36 , Oswestry Disability Index ( ODI ) , and Rol and -Morris ( R-M ) surveys were used for subjective evaluation of the result of the surgery and the Visual Analogue Scale ( VAS ) for pain severity . Plain roentgenograms including anteroposterior , lateral and oblique views , and lateral plus frontal bending views of the instrumented spine and CT scan were used to evaluate the evolution of the posterolateral fusion in all groups and sides . Two independent senior orthopaedic radiologists were asked to evaluate first the evolution of the dorsolateral bony fusion 3–48 months postoperatively with the Christiansen ’s radiologic method , and secondly the hydroxyapatite resorption course in the spines of groups B and C. The diagnosis of solid spinal fusion was definitively confirmed with the addition of the bending views , CT scans and self- assessment scores . The intraobserver and interobserver agreement ( r ) for radiological fusion was 0.71 and 0.69 , respectively , and 0.83 and 0.76 for evaluation of CH resorption . T12−S1 lordosis and segmental angulation did not change postoperatively . There was no radiological evidence for non-union on the plain roentgenograms and CT scans . Radiological fusion was achieved 1 year postoperatively and was observed in all groups and vertebral segments . Six months postoperatively there was an obvious resorption of hydroxyapatite granules at the intertransverse intersegmental spaces in the right side of the spines of group B and both sides of group C. The resorption of hydroxyapatite was completed 1 year postoperatively . Bone bridging started in the third month postoperatively in all instrumented spines and all levels posteriorly as well as between the transverse processes in the spines of the group A and on the left side of the spines of group B where IBG was applied . SF-36 , ODI , and R-M score improved postoperatively in a similar way in all groups . There was one pedicle screw breakage at the lowermost instrumented level in group A and two in group C without radiologically visible pseudarthrosis , which were considered as having non-union . Operative time and blood loss were less in the patients of group C , while donor site complaints were observed in the patients of the groups A and B only . This study showed that autologous IBG remains the “ gold st and ard ” for achieving solid posterior instrumented lumbar fusion , to which each new graft should be compared . The incorporation of coralline hydroxyapatite mixed with local bone and bone marrow needs adequate bleeding bone surface . Subsequently , hydroxyapatite was proven in this series to not be appropriate for intertransverse posterolateral fusion , because the host bone in this area is little . However , the use of hydroxyapatite over the decorticated laminae that represents a wide host area was followed by solid dorsal fusion within the expected time Study Design . A prospect i ve , r and omized and controlled study . Objectives . To evaluate the osteoinductive property of Osteogenic Protein-1 ( OP-1 or BMP-7 ) and fusion rate in human instrumented posterolateral lumbar fusion through radiographic examination , surgical exploration , and histologic assessment . Summary of Background Data . The use of osteoinductive agents is a current topic in spinal fusion . Numerous pre clinical investigations have demonstrated efficacy of osteoinductive proteins in spinal fusion , but few human clinical studies have been reported . Methods . Nineteen patients with L3–L4 or L4–L5 degenerative spondylolisthesis underwent posterolateral lumbar fusion using pedicle screw instrumentation .  The patients were r and omized to receive either OP-1 Putty ( 3.5 mg OP-1/g of collagen matrix per side ) alone ( n = 9 ) , or local autograft with HA-TCP granules ( n = 10 ) . Fusion status was evaluated using plain radiography and CT scan . Radiographic fusion criteria included less than 5 ° of angular motion , less than 2 mm of translation , and evidence of bridging bone in the posterolateral lumbar area in which the graft material s were placed following decortication . After a minimum 1-year follow-up , the patients who showed radiographic evidence of fusion underwent instrumentation removal and surgical exploration of the fusion site . Biopsy specimens were taken from the fusion mass and evaluated histologically . Results . Radiographic fusion rate was 7 of 9 OP-1 patients and 9 of 10 control patients . Based on surgical exploration of these 16 patients , new bone formation was macroscopically observed in the posterolateral lumbar region in all cases ; however , solid fusion was observed in 4 of 7OP-1 and 7 of 9 HA-TCP/autograft patients . Histologic assessment demonstrated viable bone in 6 of 7 OP-1 patients . All the control ( HA-TCP/autograft ) specimens contained viable bone and fibrous tissue surrounding ceramic granules , suggesting slow incorporation of the graft material . Conclusions . In a human posterolateral lumbar spine trial , OP-1 reliably induced viable amounts of new bone formation , but the fusion success rate evaluated by surgical exploration was only 4 of 7 Study Design . A prospect i ve r and omized clinical study was conducted . Objective . To determine whether the dose and carrier that were successful in rhesus monkeys could induce consistent radiographic spine fusion in humans . Summary of Background Data . Pre clinical studies have demonstrated that recombinant human bone morphogenetic protein-2 ( rhBMP-2 ) , an osteoinductive bone morphogenetic protein , is successful at generating spine fusion in rabbits and rhesus monkeys . Methods . For this study , 25 patients undergoing lumbar arthrodesis were r and omized ( 1:2:2 ratio ) based on the arthrodesis technique : autograft/Texas Scottish Rite Hospital ( TSRH ) pedicle screw instrumentation ( n = 5 ) , rhBMP-2/TSRH ( n = 11 ) , and rhBMP-2 only without internal fixation ( n = 9 ) . On each side , 20 mg of rhBMP-2 were delivered on a carrier consisting of 60 % hydroxyapatite and 40 % tricalcium phosphate granules ( 10 cm3/side ) . The patients had single-level disc degeneration , Grade 1 or less spondylolisthesis , mechanical low back pain with or without leg pain , and at least 6 months failure of nonoperative treatment . Results . All 25 patients were available for follow-up evaluation ( mean , 17 months ; range 12–27 months ) . The radiographic fusion rate was 40 % ( 2/5 ) in the autograft/TSRH group and 100 % ( 20/20 ) with rhBMP-2 group with or without TSRH internal fixation ( P = 0.004 ) . A statistically significant improvement in Oswestry score was seen at 6 weeks in the rhBMP-2 only group ( −17.6;P = 0.009 ) , and at 3 months in the rhBMP-2/TSRH group ( −17.0;P = 0.003 ) , but not until 6 months in the autograft/TSRH group ( −17.3;P = 0.041 ) . At the final follow-up assessment , Oswestry improvement was greatest in the rhBMP-2 only group ( −28.7 , P < 0.001 ) . The SF-36 Pain Index and PCS subscales showed similar changes . Discussion . This pilot study is the first with at least 1 year of follow-up evaluation to demonstrate successful posterolateral spine fusion using a BMP-based bone graft substitute , with radiographs and CT scans as the determinant . Consistently , rhBMP-2 was able to induce bone in the posterolateral lumbar spine when delivered at a dose of 20 mg per side with or without the use of internal fixation . Patients with spondylolisthesis classified higher than Meyerding Grade 1 or with more than 5 mm of translational motion may still require internal fixation . Some patients did smoke during the postoperative period , and all in the rhBMP-2 groups still obtained solid fusions . Conclusions . Consistently , rhBMP-2 with the biphasic calcium phosphate granules induced radiographic posterolateral lumbar spine fusion with or without internal fixation in patients whose spondylolisthesis did not exceed Grade 1 . Statistically greater and quicker improvement in patient-derived clinical outcome was measured in the rhBMP-2 groups The associated morbidity of allograft(s ) as bone graft exp and ers in spinal surgery has prompted the search for alternatives . The efficacy of Vitoss/Beta Tricalcium Phosphate ( B-TCP : OrthoVita , Malvern PA , USA ) , an artificial bone substitute , combined with lamina autograft ( 50:50 mix ) in 40 prospect i ve posterolateral fusions utilizing pedicle/screw instrumentation was analyzed . Multilevel lumbar laminectomies ( average 3.7 levels ) were accompanied by 1 ( 27 patients ) and 2 level ( 13 patients ) fusions . Two neuroradiologists independently assessed fusion progression on dynamic x-rays and 2D-CT studies performed at 3 , 6 , and up to 12 months postoperatively . Outcomes were quantified utilizing Odom Criteria and Short-Form 36 ( SF-36 ) question naires ( preoperatively ; and 3 , 6 , and 12 months postoperatively ) . By the sixth postoperative month , fusion was neuroradiologically confirmed on both dynamic x-rays and CT studies for 26 of 27 single level fusions ( 1 pseudarthrosis ) , and 11 of 13 two level fusions ( L4-S1 ) . Odom Criteria 3 , 6 , and 12 months postoperatively revealed continued improvement for all patients . SF-36 outcomes , however , revealed deterioration on 2 Health Scales ( Role Physical , Role Emotional ) 3 and 6 months post-operatively , and minimal to marked improvement on 6 Health Scales ( PF , V , PF , V , SF , BP ) . Twelve months postoperatively improvement occurred on all 8 Health Scales , exceeding pre-operative baselines ; minimal ( RP , GH ) , mild ( MH ) , moderate ( PF , BP , V , SF ) , and marked improvement ( RE ) . Although Vitoss/B-TCP and laminar autograft result ed in pseudarthrosis for 1 of 27 single level and 2 of 13 two level posterolateral instrumented lumbar fusions , only 1 of the latter patients required a secondary fusion Study Design . This prospect i ve study analyzed the influence of transpedicular instrumented on the operative treatment of patients with degenerative spondylolisthesis and spinal stenosis . Objectives . To determine whether the addition of transpedicular instrumented improves the clinical outcome and fusion rate of patients undergoing posterolateral fusion after decompression for spinal stenosis with concomitant degenerative spondylolisthesis . Summary of Background Data . Decompression is often necessary in the treatment of symptomatic patients who have degenerative spondylolisthesis and spinal stenosis . Results of recent studies demonstrated that outcomes are significantly improved if posterolateral arthrodesis is performed at the listhesed level . A meta‐ analysis of the literature concluded that adjunctive spinal instrumentation for this procedure can enhance the fusion rate , although the effect on clinical outcome remains uncertain . Methods . Seventy‐six patients who had symptomatic spinal stenosis associated with degenerative lumbar spondylolisthesis were prospect ively studied . All patients underwent posterior decompression with concomitant posterolateral intertransverse process arthrodesis . The patients were r and omized to a segmental transpedicular instrumented or noninstrumented group . Results . Sixty‐seven patients were available for a 2‐year follow‐up  . Clinical outcome was excellent or good in 76 % of the patients in whom instrumentation was placed and in 85 % of those in whom no instrumentation was placed ( P = 0.45 ) . Successful arthrodesis occurred in 82 % of the instrumented cases versus 45 % of the noninstrumented cases ( P = 0.0015 ) . Overall , successful fusion did not influence patient outcome ( P = 0.435 ) . Conclusions . In patients undergoing single‐level posterolateral fusion for degenerative spondylolisthesis with spinal stenosis , the use of pedicle screws may lead to a higher fusion rate , but clinical outcome shows no improvement in pain in the back and lower Study Design Prospect i ve , matched , and controlled study . Objective To evaluate the efficacy of hydroxyapatite-bioactive glass ceramic composite ( Chitra-HABg ) as a st and -alone graft substitute in promoting posterolateral fusion in the lumbar spine as compared with autologous bone . Background The use of ceramics as st and -alone graft substitutes in posterolateral fusion remains controversial . The Chitra-HABg is a new composite that has undergone clinical trials in various orthopedic applications with excellent clinical and radiologic outcomes . Methods Twenty-four patients underwent instrumented posterolateral fusion , with Chitra-HABg laid on the left intertransverse bed and autogenous graft on the right side . The primary outcome measure was radiologic consolidation of the graft , and secondary outcome measures were the work status and the Modified Oswestry Disability index . The McNamara and Student χ2 test were applied for statistical analysis . Results Although the study was prematurely terminated owing to the high incidence of resorption of Chitra-HABg , 22 of the 24 subjects were followed-up for a minimum of 1 year . At the end of 1-year , excellent radiologic outcome was seen on the right side ( autogenous graft ) in all the cases , whereas 95 % ( 21/22 ) of the cases had poor consolidation on the left side ( Chitra-HABg ) . The clinical outcome was rated as good in 16/22 ( 73 % ) patients , fair in 5 , and poor in only 1 patient , but this had no statistically significant association with the consolidation of the fusion mass . Conclusions This study clearly demonstrates that hydroxyapatite-bioactive glass ceramic composites ( Chitra-HABg ) has no role as st and -alone bone graft substitutes in posterolateral fusion of the lumbar spine , as the composite undergoes resorption without the formation of bridging callus . Level of Evidence Level 1 Study Design . Retrospective cohort study . Objective . To determine the effect on fusion of adding platelet gel to autologous iliac crest graft . Summary of Background Data . Platelet gel is an osteoinductive material prepared by ultra-concentration of platelets and contains multiple growth factors . Proprietary commercial methods are available for harvesting autologous platelet gel concentrates for use as graft supplement in spine fusions . Methods . We review ed 76 consecutive patients who underwent instrumented posterolateral lumbar fusion with autologous iliac crest bone graft mixed with autologous growth factor ( AGF ) . A control group was r and omly selected from patients who underwent instrumented posterolateral lumbar fusion with autologous bone graft alone .  The groups were matched for age , sex , smoking history , and number of levels fused . Demographic , surgical , and clinical data were collected from medical records . Diagnosis of nonunion was based on exploration during revision surgery or evidence of nonunion on computerized tomography . The Fisher exact test was used to compare fusion rates . Results . In both groups , mean age was 50 years , and 24 % were smokers . The nonunion rate was 25 % in the AGF group and 17 % in the control group . This difference was not statistically significant ( P = 0.18 ) . Conclusions . Platelet gel preparation requires blood draws from the patient . This procedure adds to the risk and cost of surgery . The technique for AGF harvest evaluated in this study provides the highest concentration of platelets among the commercially available methods . Despite this , we showed that platelet gel failed to enhance fusion rate when added to autograft in patients undergoing instrumented posterolateral spinal fusion . The authors do not recommend the use of platelet gel to supplement autologous bone graft during instrumented posterolateral spinal fusion BACKGROUND Beta tricalcium phosphate ( B-TCP ) is increasingly used to supplement lamina autograft to perform posterolateral lumbar-instrumented arthrodesis . PURPOSE To determine the radiographic arthrodesis and pseudarthrosis rates after multisegment lumbar laminectomies and one- or two-segment posterolateral instrumented fusion using lamina autograft and an artificial bone graft exp and er B-TCP ( Vitoss ; Orthovita , Malvern , PA , USA ) . STUDY DESIGN / SETTING To document radiographic arthrodesis/pseudarthrosis rates using lamina autograft and B-TCP . PATIENT SAMPLE One hundred patients with lumbar spinal stenosis underwent multisegment laminectomies ( average 3.6 segments ) and one- ( 78 patients ) or two- ( 22 patients ) segment posterolateral instrumented arthrodesis .  OUTCOME MEASURES Two-year postoperative outcomes were assessed using Short-Form 36 question naires . METHODS The arthrodesis mass consisted of lamina autograft and B-TCP . Two independent neuroradiologists , using both dynamic X-rays and 2D-CT studies performed 3 , 4.5 , 6 , and up to 12 months postoperatively , documented radiographic arthrodesis progression . RESULTS One-segment arthrodesis was performed in 79 patients ; 74 ( 93.7 % ) were radiographically fused " early " ( 6.5 postoperative months ) , 2 ( 2.5 % ) fused " late " ( 6.5 - 12 months ) , and 3 ( 3.8 % ) exhibited pseudarthrosis . Two-segment arthrodesis was performed in 21 patients ; 14 ( 66.7 % ) radiographically fused " early , " 5 ( 23.8 % ) fused " late , " and 2 ( 9.5 % ) exhibited pseudarthrosis . Although chi-square analyses revealed a significant increase in the number of " late " radiographic fusions occurring for patients undergoing two-level arthrodesis , no significant difference in radiographic pseudarthrosis rates was noted between the two patient population s. In both groups , Short-Form 36 question naires revealed nearly comparable maximal improvement on seven of eight Health Scales by the second postoperative year . CONCLUSIONS At 6.5 months after multisegment lumbar laminectomies with posterolateral instrumented lumbar arthrodesis using lamina autograft/B-TCP , more one-segment ( 93.7 % ) versus two-segment ( 66.7 % ) radiographic arthrodesis occurred . By 1 year after operation , there was no significant difference in fusion rates between one- and two-segment radiographic arthrodeses Study Design . A prospect i ve r and omized study investigated the radiographic progress of fusion at 6 , 12 , and 24 months in 42 patients who underwent a single-level anterior lumbar interbody fusion using cylindrical interbody fusion cages . Objective . To determine the patterns and rates of osteoinduction associated with the use of recombinant human bone morphogenetic protein type 2 ( rhBMP-2 ) and an absorbable collagen sponge carrier in anterior lumbar interbody fusion with a tapered cylindrical fusion device . Summary of Background Data . Studies have shown that rhBMP-2 used with allograft dowels increases the rate of interbody fusion by promoting osteoinduction and enhancing incorporation of the allograft . In a small series of human patients undergoing anterior lumbar interbody fusion with a tapered cylindrical fusion cage , rhBMP-2 has been shown to promote osteoinduction and fusion . Methods . In this prospect i ve nonblinded study , 42 patients were r and omly divided into two groups . The investigational group underwent interbody fusion using two tapered cylindrical fusion cages ( LT – CAGE ) and rhBMP-2 on an absorbable collagen sponge , and a control group underwent the procedure , receiving the devices and autogenous iliac crest bone graft . Plain radiographs and computed tomographic scans were used to evaluate the pattern of osteoinduction in the interbody space and the progression of fusion 6 , 12 , and 24 months after surgery . Results . All the patients who received rhBMP-2 showed radiographic evidence of osteoinduction in the interbody cages 6 months after surgery . The density in the cages had increased an average of 142 Hounsfield units by 6 months . At 12 months , the increase had reached 228.7 Hounsfield units New bone formation occurred in the disc space outside the cages by 6 months in 18 of the patients in the investigational group ( 18/22 ; 82 % ) . By 24 months , all the investigational patients showed new formation outside the cages . In the autograft control group , the density in the cages increased an average of 42 Hounsfield units , and 10 patients ( 10/20 ; 50 % ) showed evidence of bone formation outside the cages . Conclusions . The use of rhBMP-2 is a promising method for facilitating anterior intervertebral spinal fusion in patients who have undergone anterior lumbar fusion surgery Study Design . A prospect i ve , nonblinded , multicenter study of outcomes in patients undergoing single-level anterior lumbar discectomy and interbody fusion with InFUSE ™ Bone Graft .  Objective . To determine the safety and effectiveness of InFUSE ™ Bone Graft applied to an absorbable collagen sponge in anterior lumbar interbody fusion with threaded cortical allografts . Summary of Background Data . In primates , InFUSE ™ Bone Graft used with allograft dowels was shown to increase rates of interbody fusion by promoting osteoinduction and enhancing incorporation of the allograft . Recently , in a small series of human patients undergoing anterior lumbar interbody fusion with a tapered cylindrical metal fusion cage , InFUSE ™ Bone Graft has been shown to promote osteoinduction and fusion . Methods . Forty-six patients underwent a single-level anterior lumbar discectomy and interbody fusion at five investigational sites . They were r and omly assigned to one of two groups , and the results in the investigational patients who received threaded cortical allograft dowels with InFUSE ™ Bone Graft were compared with those in the control patients who received threaded allograft dowels with autogenous iliac crest bone graft . Patients ’ clinical outcomes were assessed using neurologic status , work status , and Oswestry Low Back Pain Disability , Short Form-36 , and back and leg pain question naires . Anteroposterior , lateral , flexion-extension radiographs , and computed tomography scans were used to evaluate the progression of fusion at 6 , 12 , and 24 months after surgery . Results . All patients who received InFUSE ™ Bone Graft  showed radiographic evidence of bony induction and early incorporation of the cortical allografts . All patients in this group had fusions at 12 months that remained fused at 24 months . At 12 and 24 months , the investigational group showed higher rates of fusion and improved neurologic status and back and leg pain when compared with the control group . There were no unanticipated adverse events related to the use of InFUSE ™ Bone Graft . Conclusion . The use of InFUSE ™ Bone Graft is a promising method of facilitating anterior intervertebral spinal fusion , decreasing pain , and improving clinical outcomes in patients who have undergone anterior lumbar fusion surgery with structural threaded cortical allograft bone dowels Study Design . A prospect i ve , r and omized , controlled , multicenter clinical study was conducted . Objective . To compare the clinical and radiographic outcomes of patients treated with OP-1 ( BMP-7 ) Putty to autogenous iliac crest bone graft for one-level uninstrumented posterolateral fusion of the lumbar spine following decompressive laminectomy for the treatment of symptomatic degenerative spondylolisthesis with spinal stenosis . Background . Pre clinical studies have demonstrated that osteoinductive recombinant human osteogenic protein1 in the form of OP-1 Putty is successful at achieving a posterolateral fusion in rabbits and dogs without any significant safety concerns . Methods . Thirty-six patients with degenerative lumbar spondylolisthesis and symptoms of neurogenic claudication were r and omized ( 2:1 ) to either OP-1 Putty ( 3.5 mg of OP-1 per side ) or autogenous iliac crest bone graft for one-level uninstrumented posterolateral fusion following a decompressive laminectomy . Enrollment in the study was complete when 24 OP-1 Putty patients and 12 autograft patients had been r and omized and treated . A patient administered Oswestry scale and SF-36 scale were used to determine clinical outcomes . Independent , blinded neuroradiologists review ed both static and dynamic radiographs to determine fusion status . Results . At the 1-year follow-up , 32 patients were available for clinical analysis and 29 patients were available for radiographic review .  Clinical success as measured on the Oswestry scale was achieved by 18 of 21 ( 86 % ) OP-1 Putty patients and 8 of 11 ( 73 % ) autograft patients . SF-36 pain index scores showed similar results . Fourteen of 19 ( 74 % ) OP-1 Putty patients and 6 of 10 ( 60 % ) autograft patients achieved a successful posterolateral fusion fulfilling all fusion criteria . Of the 29 evaluable patients , 15 were both clinical and radiographic successes , 5 were radiographic successes but were clinical failures , 1 patient was both a radiographic and clinical failure , and 8 patients were radiographic failures but were clinical successes . No systemic toxicity , ectopic bone formation , recurrent stenosis , or other adverse events related to the OP-1 Putty implant were observed . Conclusion . Although the posterolateral spine is a challenging fusion environment in patients with degenerative spondylolisthesis , successful radiographic fusion was obtained using OP-1 Putty at a rate that was similar to autograft given the number of patients in this study . Importantly , there were no apparent adverse consequences related to the use of the OP-1 Putty implant in this patient population There have been no reports on the effects of the mixture ratio of local bone graft to artificial bone on the outcome of intervertebral bone fusion . The purpose of this study was to determine whether the mixture ratio of local bone removed from laminae and spinous processes to apatite- and wollastonite-containing glass ceramic ( AWGC ) granules affected fusion rates in spinal fusion . Posterolateral lumbar fusion at two levels without spinal instrumentation was performed in 35 patients who were diagnosed with lumbar spinal canal stenosis . The patients were r and omly divided into three groups , each of which received a different mixture ratio of local bone to AWGC granules : 2:1 , 1:1 , and 1:2 . The total mass of grafted bone was 20 g in all three groups . The fusion rate was approximately 80 % in all three groups . Our results indicate that lumbar posterolateral fusion can be successfully achieved even when the mixture ratio of local bone graft to AWGC granules is 1:2 Study Design One hundred forty four patients who underwent lumbar spine fusions had autografts placed on one side as a control and on the opposite side one of the following types of graft material was placed : iliac autograft , demineralized cancellous chips , demineralized cortical powder , demineralized cortical powder mixed with autograft , or mineralized cancellous chips . Alar anteroposterior and lateral postoperative radiographs were review ed by three independent observers and grade d for quality of fusion mass bilaterally . The follow-up was 14 to 27 months . Objectives This study evaluated the efficacy of various types of ethylene oxide-sterilized allograft bone used for spine fusions and compared them with autograft iliac bone in the same patient . Summary of Background Data Previous studies comparing autograft with allograft showed poorer fusion rates with allograft with posterior fusions . Most of the previous studies included smaller numbers of patients . No previous studies compared ethylene oxidetreated allograft with autograft . Results An analysis of the radiographs at a minimum of 1 year postoperatively revealed significantly lower values when allograft alone or in combination with autograft was used in comparison to autograft alone . Conclusions Ethylene oxide-treated allograft is inferior to autograft and should not be used for posterior lumbar fusions BACKGROUND CONTEXT The artificial bone-volume exp and er , beta tricalcium phosphate ( B-TCP , Vitoss , OrthoVita , Malvern , PA ) , is increasingly used to supplement autograft in posterolateral lumbar fusions . PURPOSE To determine fusion rates/ outcomes using B-TCP/autograft . STUDY DESIGN / SETTING Fusion rates and outcomes were assessed for 60 predominantly geriatric patients undergoing multilevel lumbar laminectomies and 1- to 2-level noninstrumented fusions using B-TCP/autograft .  PATIENT SAMPLE Patients on average were 70 years old . OUTCOME MEASURES Odom 's criteria and Short-Form 36 ( SF-36 ) outcomes were studied 2 years postoperatively . METHODS Sixty patients underwent an average of 5.4-level laminectomies with 1- to 2-level noninstrumented fusions . Based on dynamic X-ray/magnetic resonance/computed tomography ( CT ) studies , laminectomies addressed multilevel stenosis ( 60 patients ) , ossification of the yellow ligament ( 46 patients ) , disc herniations ( 20 patients ) , or synovial cysts ( 8 patients ) , and fusions addressed degenerative spondylolisthesis ( 48 patients ) , spondylolisthesis/lysis ( 2 patients ) , or degenerative scoliosis ( 10 patients ) . The fusion mass on each side contained half of all harvested autograft combined with one to 1.5 strips of B-TCP ( saturated in 10cc of bone marrow aspirate/strip ) . Fusion rates were documented by two independent neuroradiologists using both dynamic X-rays , and thin-cut CT ( 2-dimensional/3-dimensional CT ) studies obtained up to 2 years postoperatively . Odom 's criteria and SF-36 outcomes were assessed over the same interval . RESULTS Pseudarthrosis was documented in nine ( 15 % ) patients . Two years postoperatively , Odom 's criteria revealed 28 excellent , 23 good , 5 fair , and 4 poor results , whereas SF-36 data revealed improvement on 6 of 8 Health Scales in all patients . CONCLUSIONS A 15 % pseudarthrosis rate followed multilevel laminectomy and 1- to 2-level noninstrumented posterolateral fusion using lamina autograft/B-TCP
Abstract Background Iliac crest has long been the gold st and ard for lumbar fusion , but concerns over donor site morbidity have led to a wide variety of bone graft substitutes .
Despite prolific research , a general consensus is yet to be reached on bone graft material s that lead to optimal fusion .
Purpose The purpose of this review is to evaluate the current literature for bone graft material options that maximize fusion rate in posterolateral lumbar fusion surgery .