human
***TASK*** the task is to summarize an input biomedical literature in six sentences 
    ***INPUT*** the input is a biomedical literature 
    ***OUTPUT*** the output is the summary of an input biomedical literature in six sentences 
    ***DOCUMENTATION*** 
    ***EXAMPLES*** 
    Input: 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 BACKGROUND Numerous pre clinical and clinical studies have reported on the use of platelet concentrates to promote tissue healing . The results in spinal fusion applications are limited and controversial . PURPOSE The purpose of the current prospect i ve clinical cohort study is to assess the effect of Autologous Growth Factors ( AGF ) on lumbar interbody fusion with specific attention paid to determination of clinical and radiographic outcomes . STUDY DESIGN / SETTING Prospect i ve clinical study PATIENT SAMPLE C and i date s for anterior-posterior lumbar fusion with diagnosis of degenerative disc disease and /or up to grade I spondylolytic spondylolisthesis based on positive provocative discography . OUTCOME MEASURES Clinical ( visual analogue pain scale/functional outcome assessment ) and radiographic outcomes ( fusion on computed tomography at 6 months and plain radiographs at 12 and 24 months ) . METHODS Thirty-seven patients were assigned to st and ard anterior-posterior interbody fusion L2-S1 ( single or two-level ) using iliac crest bone graft ( autograft group : 22 patients with 32 levels operated ) or allograft combined with autogenous growth factors ( AGF group : 15 patients with 25 levels operated ) . Radiographic outcomes were collected at 6 months postsurgery with computed tomography and at 12 and 24 months with plain radiographs . Pre- and postoperative clinical outcome measures included visual analog scores ( VAS ) for back and leg pain ( 0 - 10 ) , SF-36 scores , and Oswestry disability determination . Average clinical and radiographic follow-up for the autograft group was 24.3+/-5.6 months ( 12 - 36 months ) and AGF was 25.7+/-7.5 ( 6 - 40 months ) . RESULTS Fusion incorporation at each end plate was determined at 56 % in both autograft and AGF ( p = NS ) patients based on computed tomography at 6 months with minimal subsidence noted and no direct correlation between the incidence or degree of cage subsidence and bone graft technique . The 12- and 24-month radiographic results confirmed an 85 % arthrodesis rate for the autograft patients , whereas the AGF patients had an 89 % fusion rate ( p = NS ) . Clinical outcomes were similar for both groups and no significant differences were noted for pain or functional outcome improvements . CONCLUSIONS AGF combined with an allograft carrier is equivalent in radiographic and clinical outcomes to autograft in one- or two-level lumbar interbody fusion with supplemental posterior fixation and , thus , eliminates any morbidity from iliac crest bone graft harvesting . AGF combined with an appropriate carrier is a reasonable alternative to autograft and expensive bone induction technologies . Further research is still required to examine the optimum carriers , preparation and formulation , and platelet concentrations for this technology 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 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 BACKGROUND CONTEXT There is mounting evidence supporting the efficacy of bone morphogenetic protein ( BMP ) for both anterior interbody and posterolateral lumbar fusion . However , the relative cost of BMP remains an important concern for physicians , hospitals , and payers . PURPOSE The purpose of this study is to report on the perioperative costs for patients treated with rhBMP-2 as compared with an iliac crest bone graft ( ICBG ) supplemented with graft extenders .  STUDY DESIGN / SETTING A prospect i ve r and omized controlled trial of rhBMP-2/ACS ( Infuse Bone Graft ; Medtronic Sofamor Danek , Memphis , TN ) versus ICBG+/-graft extender for lumbar spine fusion in patients over 60 years old . PATIENT SAMPLE One hundred two patients over 60 years old who required a posterolateral lumbar spine fusion r and omized between receiving rhBMP-2/ACS or ICBG .  OUTCOME MEASURES All health-care costs over the first 3 months after surgery . METHODS As part of a prospect i ve r and omized trial of rhBMP-2/ACS versus ICBG+/-graft extender for lumbar spine fusion , all costs over the first 3 months after surgery were directly recorded by a dedicated coder funded by Norton Healthcare , Louisville , KY . A dedicated research nurse also followed all patients throughout their hospital stay and posthospitalization recovery to identify any adverse events or additional outpatient medical care . RESULTS Fifty patients received rhBMP-2/ACS and 52 underwent ICBG harvest . The mean hospital cost for the index admission was $ 24,736 for the rhBMP-2/ACS group and $ 21,138 for the ICBG group . Mean inpatient physician costs were $ 5,082 in the rhBMP-2/ACS group and $ 5,316 in the ICBG group . Costs associated with posthospital rehabilitation averaged $ 4,906 in 
    Output:
    
agent
***TASK*** the task is to summarize an input biomedical literature in six sentences 
    ***INPUT*** the input is a biomedical literature 
    ***OUTPUT*** the output is the summary of an input biomedical literature in six sentences 
    ***DOCUMENTATION*** 
    ***EXAMPLES*** 
    Input: 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 BACKGROUND Numerous pre clinical and clinical studies have reported on the use of platelet concentrates to promote tissue healing . The results in spinal fusion applications are limited and controversial . PURPOSE The purpose of the current prospect i ve clinical cohort study is to assess the effect of Autologous Growth Factors ( AGF ) on lumbar interbody fusion with specific attention paid to determination of clinical and radiographic outcomes . STUDY DESIGN / SETTING Prospect i ve clinical study PATIENT SAMPLE C and i date s for anterior-posterior lumbar fusion with diagnosis of degenerative disc disease and /or up to grade I spondylolytic spondylolisthesis based on positive provocative discography . OUTCOME MEASURES Clinical ( visual analogue pain scale/functional outcome assessment ) and radiographic outcomes ( fusion on computed tomography at 6 months and plain radiographs at 12 and 24 months ) . METHODS Thirty-seven patients were assigned to st and ard anterior-posterior interbody fusion L2-S1 ( single or two-level ) using iliac crest bone graft ( autograft group : 22 patients with 32 levels operated ) or allograft combined with autogenous growth factors ( AGF group : 15 patients with 25 levels operated ) . Radiographic outcomes were collected at 6 months postsurgery with computed tomography and at 12 and 24 months with plain radiographs . Pre- and postoperative clinical outcome measures included visual analog scores ( VAS ) for back and leg pain ( 0 - 10 ) , SF-36 scores , and Oswestry disability determination . Average clinical and radiographic follow-up for the autograft group was 24.3+/-5.6 months ( 12 - 36 months ) and AGF was 25.7+/-7.5 ( 6 - 40 months ) . RESULTS Fusion incorporation at each end plate was determined at 56 % in both autograft and AGF ( p = NS ) patients based on computed tomography at 6 months with minimal subsidence noted and no direct correlation between the incidence or degree of cage subsidence and bone graft technique . The 12- and 24-month radiographic results confirmed an 85 % arthrodesis rate for the autograft patients , whereas the AGF patients had an 89 % fusion rate ( p = NS ) . Clinical outcomes were similar for both groups and no significant differences were noted for pain or functional outcome improvements . CONCLUSIONS AGF combined with an allograft carrier is equivalent in radiographic and clinical outcomes to autograft in one- or two-level lumbar interbody fusion with supplemental posterior fixation and , thus , eliminates any morbidity from iliac crest bone graft harvesting . AGF combined with an appropriate carrier is a reasonable alternative to autograft and expensive bone induction technologies . Further research is still required to examine the optimum carriers , preparation and formulation , and platelet concentrations for this technology 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 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 BACKGROUND CONTEXT There is mounting evidence supporting the efficacy of bone morphogenetic protein ( BMP ) for both anterior interbody and posterolateral lumbar fusion . However , the relative cost of BMP remains an important concern for physicians , hospitals , and payers . PURPOSE The purpose of this study is to report on the perioperative costs for patients treated with rhBMP-2 as compared with an iliac crest bone graft ( ICBG ) supplemented with graft extenders .  STUDY DESIGN / SETTING A prospect i ve r and omized controlled trial of rhBMP-2/ACS ( Infuse Bone Graft ; Medtronic Sofamor Danek , Memphis , TN ) versus ICBG+/-graft extender for lumbar spine fusion in patients over 60 years old . PATIENT SAMPLE One hundred two patients over 60 years old who required a posterolateral lumbar spine fusion r and omized between receiving rhBMP-2/ACS or ICBG .  OUTCOME MEASURES All health-care costs over the first 3 months after surgery . METHODS As part of a prospect i ve r and omized trial of rhBMP-2/ACS versus ICBG+/-graft extender for lumbar spine fusion , all costs over the first 3 months after surgery were directly recorded by a dedicated coder funded by Norton Healthcare , Louisville , KY . A dedicated research nurse also followed all patients throughout their hospital stay and posthospitalization recovery to identify any adverse events or additional outpatient medical care . RESULTS Fifty patients received rhBMP-2/ACS and 52 underwent ICBG harvest . The mean hospital cost for the index admission was $ 24,736 for the rhBMP-2/ACS group and $ 21,138 for the ICBG group . Mean inpatient physician costs were $ 5,082 in the rhBMP-2/ACS group and $ 5,316 in the ICBG group . Costs associated with posthospital rehabilitation averaged $ 4,906 in 
    Output:
    