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: 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 : The objective of this study is to compare the clinical , functional , and radiological outcomes of using bone-filled Polymethylmethacrylate ( PMMA ) implant as an inexpensive alternative to Polyetheretherketone ( PEEK ) cage and Autologous bone graft ( ABG ) fusion after anterior cervical discectomy ( ACD ) for the treatment of single level cervical disc disease . Methods : 60 patients were prospect ively r and omized according to the material used for fusion after ACD into : 1 ) PMMA implant ; 2 ) ABG ; and 3 ) PEEK implant . The clinical outcomes were evaluated using Visual Analogue Scale ( VAS ) , whereas the functional outcomes were evaluated using Odom 's criteria . Radiological evaluations were also conducted using radiography and Computerized tomography ( CT ) scans and considered the following factors ; bony fusion , cervical stability and disc space height ( DSH ) changes . The post- operative outcomes were evaluated at the following intervals ; 2 weeks , 3 and 6 months . Results : The clinical outcomes demonstrated insignificant difference among the three treated groups throughout their follow up period . ABG group showed significant lower satisfactory functional outcomes ( 68.1 % ) compared to PMMA and PEEK groups ( 85 % and 88.9 % , respectively ) at the 2-week post operative evaluation , but the ABG group showed closer functional outcomes to the PMMA and PEEK groups at the 3 and 6-month post operative evaluations . Despite the inferior bony fusion rates of the PMMA group ( 30 % ) compared to ABG group ( 86.3 % ) and PEEK group ( 77.7 % ) at the 6-month post operative evaluation , the clinical and functional outcomes were comparable . Conclusions : Bone-filled PMMA implant is a reliable treatment option ; despite its inferior fusion rate at the 6-month postoperative evaluation , it still provides acceptable segmental stability , satisfactory clinical and functional outcomes that are comparable to ABG and PEEK grafting procedures BACKGROUND CONTEXT Multiple bone graft substitutes for spinal fusion have been studied with varying results . PURPOSE The purpose of this study was to assess the effectiveness of a mineralized collagen matrix combined with bone marrow , versus autologous bone , in the same patients undergoing a posterior lumbar interbody fusion and an instrumented posterolateral lumbar fusion . STUDY DESIGN / SETTING A prospect i ve , comparative study . PATIENT SAMPLE Patients indicated for one-level posterior lumbar interbody fusion and instrumented posterolateral lumbar fusion , serving as self-controls . OUTCOME MEASURES  Thin-cut computed tomographic scans with sagittal reconstruction and plain radiographs , including lateral flexion/extension views were performed and assessed at 12 and 24 months after surgery . Oswestry Disability Index and Visual Analog Scale question naires were completed by all patients preoperatively and at 12 and 24 months after surgery . METHODS After informed consent and failure of nonoperative treatment , 25 consecutive patients requiring one-level instrumented posterolateral fusion combined with posterior interbody fusion were enrolled in the study . Mineralized collagen bone graft substitute combined with bone marrow aspirate was used on one side of the posterolateral fusion , with iliac crest autograft on the contralateral side . RESULTS A fusion rate of 84 % ( 21/25 ) was achieved for the autologous bone grafts and 80 % ( 20/25 ) for the bone graft substitute . The interbody fusion rate was 92 % ( 23/25 ) . Mean Oswestry Disability Index ( ODI ) scores decreased 57.2 % at 12 months and 55.6 % at 24 months , compared with baseline . CONCLUSIONS Mineralized collagen bone graft substitute exhibited similar radiographic results compared with autograft in this model . Further trials incorporating bilateral fusion , as well as posterolateral fusion alone without interbody fusion are warranted to confirm the results of this study 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 Background Porous β-calcium pyrophosphate ( β-CPP ) was developed to improve the fusion success of posterolateral lumbar fusion ( PLF ) . The possibility of accomplishing PLF using a mixture of porous β-CPP and iliac bone was studied . This paper reports the radiologic results of PLF using the β-CPP plus autograft for lumbar degenerative disease as a bone graft extender . Methods A prospect i ve , case-matched , radiographic study evaluating the results of short segment lumbar fusion using a β-CPP plus autograft was performed to compare the efficacy of β-CPP plus autograft with that of an autograft alone for short segment lumbar fusion . Thirty one consecutive patients ( 46 levels ) underwent posterolateral fusion with pedicle screw fixation and additional posterior lumbar interbody fusion .  In all patients , 3 mL of β-CPP plus 3 mL of autogenous bone graft was placed r and omly in one side of a posterolateral gutter , and 6 mL of autogenous iliac bone graft was placed on the other . The fusion rates , volumes of fusion masses , and bone absorption percentage were evaluated postoperatively using simple radiographs and 3 dimensional computed tomography ( 3D-CT ) scans . Results The control sides treated with an autograft showed significantly better Lenke scores than the study sides treated with β-CPP at 3 and 6 months postoperatively , but there was no difference between the two sides at 12 months . The fusion rates ( confirmed by 3D-CT ) were 87.0 % in the β-CPP group and 89.1 % in the autograft group , which were not significantly different . The fusion mass volumes and bone absorption percentage at 12 months postoperatively were 2.49 mL ( 58.4 % ) and 1.89 mL ( 69.5 % ) for the β-CPP and autograft groups , respectively , and mean fusion mass volume was significantly higher in the β-CPP group . Conclusions β-CPP combined with an autograft is as effective as autologous bone for grafting during instrumented posterolateral spinal fusion . These findings suggest that β-CPP bone chips can be used as a novel bone graft extender for short-segment posterolateral spinal fusion Study Design One hundred fifteen patients having symptomatic cervical disc disease were recruited prospect ively for this study . They were allocated r and omly for either autologous iliac bone graft or biocompatible osteoconductive polymer implants . Both groups were compared clinical ly and radiologically . Objectives Complications , long‐term clinical and radiologic outcome , and hospital stay were compared to determine if biocompatible osteoconductive polymer was an improvement on iliac bone graft in terms of reduced donor site pain and shortened hospital stay . Summary of Background Data Donor site morbidity is a significant problem in anterior cervical fusion . Hospital stay is another factor in the recent era of cost consciousness . Biocompatible osteoconductive polymer has been used in many centers as a biodegradable implant to circumvent these problems . Methods  Smith‐Robinson technique was used in 74 patients , and Cloward technique was used in 41 patients . Sixty‐five patients had biocompatible osteoconductive polymer implants , and 50 patients had iliac bone graft . Patients were followed‐up routinely in the outpatient clinic where pain visual analogue scale and Odom 's criteria were used for outcome evaluation . Plain radiography , computed tomography scan , and magnetic resonance imaging were used for radiologic evaluation . Results The mean hospital stay was 4.8 days for those with iliac bone graft and 4.7 days for those with biocompatible osteoconductive polymer . Clinical outcome was identical in both groups . The incidence of partial graft protrusion and postoperative intersegmental kyphosis was statistically higher with iliac bone graft ( P = 0.018 and P = 0.02 , respectively ) . “ Sclerosis ” started to form around biocompatible osteoconductive polymer like a “ halo ” at 2 months . It increased with time , and sometimes was associated with new osteophyte formation ; however , there was no biocompatible osteoconductive polymer incorporation or biodegradation . Conclusions Biocompatible osteoconductive polymer acts as a good “ spacer ” that reduces graft collapse and intersegmental kyphosis . However , it did not show any radiologic evidence of biodegradation or incorporation during the follow‐up period of 24 months Study Design . A prospect i ve r and omized trial with independent clinical and radiographic outcome review of patients receiving either hydroxyapatite or tricortical iliac crest graft for cervical interbody fusion was conducted . Objective . To determine whether coralline-derived hydroxyapatite is a suitable bone graft substitute in cervical interbody fusion . Summary of Background Data . Tricortical iliac crest bone is the “ gold st and ard ” graft material for cervical interbody fusion . Various bone substitutes have been used for this procedure to avoid potential donor site morbidity . ProOsteon 200 is a coralline-derived hydroxyapatite product , the use of which remains unclear for cervical interbody fusion . Methods . In this study , 29 patients undergoing anterior cervical fusion and plating were r and omized to receive either ProOsteon 200 or iliac crest grafts . The SF-36 and Oswestry Disability Index were used to measure clinical outcome . Postoperative radiographs were analyzed for graft fragmentation , loss of height , angular alignment , and hardware failure to assess structural integrity of the graft material . Plain radiographs and computed tomography scans were used to evaluate fusion . Results . Both the ProOsteon 200 and iliac crest groups demonstrated significant improvement in clinical outcome scores . There was no significant difference in clinical outcome or fusion rates between the two groups . Graft fragmentation occurred in 89 % 
    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: 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 : The objective of this study is to compare the clinical , functional , and radiological outcomes of using bone-filled Polymethylmethacrylate ( PMMA ) implant as an inexpensive alternative to Polyetheretherketone ( PEEK ) cage and Autologous bone graft ( ABG ) fusion after anterior cervical discectomy ( ACD ) for the treatment of single level cervical disc disease . Methods : 60 patients were prospect ively r and omized according to the material used for fusion after ACD into : 1 ) PMMA implant ; 2 ) ABG ; and 3 ) PEEK implant . The clinical outcomes were evaluated using Visual Analogue Scale ( VAS ) , whereas the functional outcomes were evaluated using Odom 's criteria . Radiological evaluations were also conducted using radiography and Computerized tomography ( CT ) scans and considered the following factors ; bony fusion , cervical stability and disc space height ( DSH ) changes . The post- operative outcomes were evaluated at the following intervals ; 2 weeks , 3 and 6 months . Results : The clinical outcomes demonstrated insignificant difference among the three treated groups throughout their follow up period . ABG group showed significant lower satisfactory functional outcomes ( 68.1 % ) compared to PMMA and PEEK groups ( 85 % and 88.9 % , respectively ) at the 2-week post operative evaluation , but the ABG group showed closer functional outcomes to the PMMA and PEEK groups at the 3 and 6-month post operative evaluations . Despite the inferior bony fusion rates of the PMMA group ( 30 % ) compared to ABG group ( 86.3 % ) and PEEK group ( 77.7 % ) at the 6-month post operative evaluation , the clinical and functional outcomes were comparable . Conclusions : Bone-filled PMMA implant is a reliable treatment option ; despite its inferior fusion rate at the 6-month postoperative evaluation , it still provides acceptable segmental stability , satisfactory clinical and functional outcomes that are comparable to ABG and PEEK grafting procedures BACKGROUND CONTEXT Multiple bone graft substitutes for spinal fusion have been studied with varying results . PURPOSE The purpose of this study was to assess the effectiveness of a mineralized collagen matrix combined with bone marrow , versus autologous bone , in the same patients undergoing a posterior lumbar interbody fusion and an instrumented posterolateral lumbar fusion . STUDY DESIGN / SETTING A prospect i ve , comparative study . PATIENT SAMPLE Patients indicated for one-level posterior lumbar interbody fusion and instrumented posterolateral lumbar fusion , serving as self-controls . OUTCOME MEASURES  Thin-cut computed tomographic scans with sagittal reconstruction and plain radiographs , including lateral flexion/extension views were performed and assessed at 12 and 24 months after surgery . Oswestry Disability Index and Visual Analog Scale question naires were completed by all patients preoperatively and at 12 and 24 months after surgery . METHODS After informed consent and failure of nonoperative treatment , 25 consecutive patients requiring one-level instrumented posterolateral fusion combined with posterior interbody fusion were enrolled in the study . Mineralized collagen bone graft substitute combined with bone marrow aspirate was used on one side of the posterolateral fusion , with iliac crest autograft on the contralateral side . RESULTS A fusion rate of 84 % ( 21/25 ) was achieved for the autologous bone grafts and 80 % ( 20/25 ) for the bone graft substitute . The interbody fusion rate was 92 % ( 23/25 ) . Mean Oswestry Disability Index ( ODI ) scores decreased 57.2 % at 12 months and 55.6 % at 24 months , compared with baseline . CONCLUSIONS Mineralized collagen bone graft substitute exhibited similar radiographic results compared with autograft in this model . Further trials incorporating bilateral fusion , as well as posterolateral fusion alone without interbody fusion are warranted to confirm the results of this study 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 Background Porous β-calcium pyrophosphate ( β-CPP ) was developed to improve the fusion success of posterolateral lumbar fusion ( PLF ) . The possibility of accomplishing PLF using a mixture of porous β-CPP and iliac bone was studied . This paper reports the radiologic results of PLF using the β-CPP plus autograft for lumbar degenerative disease as a bone graft extender . Methods A prospect i ve , case-matched , radiographic study evaluating the results of short segment lumbar fusion using a β-CPP plus autograft was performed to compare the efficacy of β-CPP plus autograft with that of an autograft alone for short segment lumbar fusion . Thirty one consecutive patients ( 46 levels ) underwent posterolateral fusion with pedicle screw fixation and additional posterior lumbar interbody fusion .  In all patients , 3 mL of β-CPP plus 3 mL of autogenous bone graft was placed r and omly in one side of a posterolateral gutter , and 6 mL of autogenous iliac bone graft was placed on the other . The fusion rates , volumes of fusion masses , and bone absorption percentage were evaluated postoperatively using simple radiographs and 3 dimensional computed tomography ( 3D-CT ) scans . Results The control sides treated with an autograft showed significantly better Lenke scores than the study sides treated with β-CPP at 3 and 6 months postoperatively , but there was no difference between the two sides at 12 months . The fusion rates ( confirmed by 3D-CT ) were 87.0 % in the β-CPP group and 89.1 % in the autograft group , which were not significantly different . The fusion mass volumes and bone absorption percentage at 12 months postoperatively were 2.49 mL ( 58.4 % ) and 1.89 mL ( 69.5 % ) for the β-CPP and autograft groups , respectively , and mean fusion mass volume was significantly higher in the β-CPP group . Conclusions β-CPP combined with an autograft is as effective as autologous bone for grafting during instrumented posterolateral spinal fusion . These findings suggest that β-CPP bone chips can be used as a novel bone graft extender for short-segment posterolateral spinal fusion Study Design One hundred fifteen patients having symptomatic cervical disc disease were recruited prospect ively for this study . They were allocated r and omly for either autologous iliac bone graft or biocompatible osteoconductive polymer implants . Both groups were compared clinical ly and radiologically . Objectives Complications , long‐term clinical and radiologic outcome , and hospital stay were compared to determine if biocompatible osteoconductive polymer was an improvement on iliac bone graft in terms of reduced donor site pain and shortened hospital stay . Summary of Background Data Donor site morbidity is a significant problem in anterior cervical fusion . Hospital stay is another factor in the recent era of cost consciousness . Biocompatible osteoconductive polymer has been used in many centers as a biodegradable implant to circumvent these problems . Methods  Smith‐Robinson technique was used in 74 patients , and Cloward technique was used in 41 patients . Sixty‐five patients had biocompatible osteoconductive polymer implants , and 50 patients had iliac bone graft . Patients were followed‐up routinely in the outpatient clinic where pain visual analogue scale and Odom 's criteria were used for outcome evaluation . Plain radiography , computed tomography scan , and magnetic resonance imaging were used for radiologic evaluation . Results The mean hospital stay was 4.8 days for those with iliac bone graft and 4.7 days for those with biocompatible osteoconductive polymer . Clinical outcome was identical in both groups . The incidence of partial graft protrusion and postoperative intersegmental kyphosis was statistically higher with iliac bone graft ( P = 0.018 and P = 0.02 , respectively ) . “ Sclerosis ” started to form around biocompatible osteoconductive polymer like a “ halo ” at 2 months . It increased with time , and sometimes was associated with new osteophyte formation ; however , there was no biocompatible osteoconductive polymer incorporation or biodegradation . Conclusions Biocompatible osteoconductive polymer acts as a good “ spacer ” that reduces graft collapse and intersegmental kyphosis . However , it did not show any radiologic evidence of biodegradation or incorporation during the follow‐up period of 24 months Study Design . A prospect i ve r and omized trial with independent clinical and radiographic outcome review of patients receiving either hydroxyapatite or tricortical iliac crest graft for cervical interbody fusion was conducted . Objective . To determine whether coralline-derived hydroxyapatite is a suitable bone graft substitute in cervical interbody fusion . Summary of Background Data . Tricortical iliac crest bone is the “ gold st and ard ” graft material for cervical interbody fusion . Various bone substitutes have been used for this procedure to avoid potential donor site morbidity . ProOsteon 200 is a coralline-derived hydroxyapatite product , the use of which remains unclear for cervical interbody fusion . Methods . In this study , 29 patients undergoing anterior cervical fusion and plating were r and omized to receive either ProOsteon 200 or iliac crest grafts . The SF-36 and Oswestry Disability Index were used to measure clinical outcome . Postoperative radiographs were analyzed for graft fragmentation , loss of height , angular alignment , and hardware failure to assess structural integrity of the graft material . Plain radiographs and computed tomography scans were used to evaluate fusion . Results . Both the ProOsteon 200 and iliac crest groups demonstrated significant improvement in clinical outcome scores . There was no significant difference in clinical outcome or fusion rates between the two groups . Graft fragmentation occurred in 89 % 
    Output:
    