***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: Study Design Prospect i ve cohort study . Purpose To assess whether additional implantation of Coflex following spinal decompression provided better clinical outcomes compared to decompression alone for symptomatic lumbar spinal stenosis ( LSS ) and to determine whether improvement in clinical outcomes correlated with changes in the radiological indices studied . Overview of Literature Literature on benefits of additional Coflex implantation compared to decompression alone for symptomatic LSS is limited . Methods Patients with symptomatic LSS who met the study criteria were offered spinal decompression with Coflex implantation . Those patients who accepted Coflex implantation were placed in the  Coflex group ( n=22 ) ; while those opting for decompression alone , were placed in the  comparison group ( n=24 ) . Clinical outcomes were assessed preoperatively , six-months , one-year and two-years postoperatively , using the Oswestry disability index , 100 mm visual analogue scale (VAS)-back pain and VAS-leg pain , and short form-36 ( SF-36 ) . Radiological indices ( disc height , foraminal height and sagittal angle ) were assessed preoperatively , six months , one year , and two years postoperatively . Results Both groups showed statistically significant ( p<0.001 ) improvement in all the clinical outcome indicators at all points in time as compared to the preoperative status . However , improvement in the Coflex group was significantly greater ( p<0.001 ) than the comparison group . Changes in the radiological indices did not correlate significantly with the improvement in clinical outcome indicators . Conclusions Additional Coflex implantation after spinal decompression in symptomatic LSS offers better clinical outcomes than decompression alone in the short-term . Changes in radiological indices do not correlate with the improvements in clinical outcomes after surgery for symptomatic LSS OBJECT Posterolateral spinal fusion ( PSF ) has long been the st and ard of care for degenerative spondylolisthesis , but less invasive , motion-preserving alternatives have been proposed to reduce the complications associated with fusion while still providing neural decompression and stabilization . The object of the current study is to evaluate the safety and efficacy of coflex Interlaminar Stabilization compared with PSF to treat low- grade spondylolisthesis with spinal stenosis . METHODS This is a prospect i ve , r and omized , multicenter FDA investigational device exemption ( IDE ) trial comparing coflex Interlaminar Stabilization with laminectomy and PSF .  A total of 322 patients from 21 sites in the US were enrolled between 2006 and 2008 for the IDE trial . The current study evaluated only the subset of patients from this overall cohort with Grade 1 spondylolisthesis ( 99 in the coflex group and 51 in the fusion group ) . Subjects were r and omized 2:1 to receive decompression and coflex interlaminar stabilization or decompression and posterolateral spinal fusion with spinal instrumentation . Data collected included perioperative outcomes , Oswestry Disability Index ( ODI ) , back and worse leg visual analog scale ( VAS ) scores , 12-Item Short Form Health Survey , Zurich Claudication Question naire ( ZCQ ) , and radiographic outcomes at a minimum of 2 years . The FDA criteria for overall device success required the following to be met : 15-point reduction in ODI , no reoperations , no major device-related complications , and no postoperative epidural injections . RESULTS At a minimum of 2 years , patient follow-up was 94.9 % and 94.1 % in the coflex and fusion control groups , respectively . There were no group differences at baseline for any demographic , clinical , or radiographic parameter . The average age was 63 years in the coflex cohort and 65 years in the fusion cohort . Coflex subjects experienced significantly shorter operative times ( p < 0.0001 ) , less estimated blood loss ( p < 0.0001 ) , and shorter length of stay ( p < 0.0001 ) than fusion controls . Both groups experienced significant improvements from baseline at 2 years in ODI , VAS back , VAS leg , and ZCQ , with no significant group differences , with the exception of significantly greater ZCQ satisfaction with coflex at 2 years . FDA overall success was achieved in 62.8 % of coflex subjects ( 59 of 94 ) and 62.5 % of fusion controls ( 30 of 48 ) ( p = 1.000 ) . The reoperation rate was higher in the coflex cohort ( 14 [ 14.1 % ] of 99 ) compared with fusion ( 3 [ 5.9 % ] of 51 , p = 0.18 ) , although this difference was not statistically significant . Fusion was associated with significantly greater angulation and translation at the superior and inferior adjacent levels compared with baseline , while coflex showed no significant radiographic changes at the operative or index levels . CONCLUSIONS Low- grade spondylolisthesis was effectively stabilized by coflex and led to similar clinical outcomes , with improved perioperative outcomes , compared with PSF at 2 years . Reoperation rates , however , were higher in the coflex cohort . Patients in the fusion cohort experienced significantly increased superior and inferior level angulation and translation , while those in the coflex cohort experienced no significant adjacent or index level radiographic changes from baseline . Coflex Interlaminar Stabilization is a less invasive , safe , and equally efficacious clinical solution to PSF to treat low- grade spondylolisthesis , and it appears to reduce stresses at the adjacent levels . Clinical trial registration no. : NCT00534235 ( Clinical Trials.gov ) The authors hypothesized that the placement of the interspinous implant would show a similar clinical outcome to the posterior lumbar interbody fusion ( PLIF ) in patients having spinal stenosis with mild segmental instability and that this method would be superior to PLIF without significantly affecting degeneration at the adjacent segments . Forty two adult patients having degenerative spinal stenosis with mild segmental instabilit who underwent implantation of Coflex ™ ( Spine motion , Germany ) or PLIF at L4 - 5 between January 2000 and December 2003 were consecutively selected and studied for one-year clinical outcome . At 12 months after surgery , both groups showed a significant improvement in the visual analogue scale score and Oswestry disability index score for both lower extremity pain and low back pain . However , the range of motion at the upper adjacent segments ( L3 - 4 ) increased significantly after surgery in the PLIF group , which was not manifested in the Coflex ™ group during the follow-up . The authors assumed that interspinous implantation can be an alternative treatment for the spinal stenosis with segmental instability in selected conditions posing less stress on the superior adjacent level than PLIF Introduction If nonoperative treatment for lumbar stenosis fails , surgery may be considered . This traditionally includes decompression often combined with fusion . Desire for less extensive surgery led to developing new techniques and implants , including an interlaminar device design ed with the goal of providing segmental stability without fusion , following decompression . The purpose of this study was to investigate 5-year outcomes associated with an interlaminar device . Methods This prospect i ve , r and omized , controlled trial was conducted at 21 centers . Patients with moderate to severe lumbar stenosis at one or two contiguous levels and up to Grade I spondylolisthesis were r and omized ( 2:1 ratio ) to decompression and interlaminar stabilization ( D+ILS ; n=215 ) using the coflex ® Interlaminar Stabilization ® device ( Paradigm Spine , LLC ) or decompression and fusion with pedicle screws ( D+PS ; n=107 ) . Clinical evaluations were made preoperatively and at 6 weeks and 3 , 6 , 12 , 18 , 24 , 36 , 48 , and 60 months postoperatively . Overall Food and Drug Administration success criteria required that a patient meet 4 criteria : 1 ) > 15 point improvement in Oswestry Disability Index ( ODI ) score ; 2 ) no reoperation , revision , removal , or supplemental fixation ; 3 ) no major device-related complication ; and 4 ) no epidural steroid injection after surgery . Results At 5 years , 50.3 % of D+ILS vs. 44 % of D+PS patients ( p>0.35 ) met the composite success criteria . Reoperation/revision rates were similar in the two groups ( 16.3 % vs. 17.8 % ; p > 0.90 ) . Both groups had statistically significant improvement through 60 months in ODI scores with 80.6 % of D+ILS patients and 73.2 % of D+PS patients demonstrating > 15 point improvement ( p>0.30 ) . VAS , SF-12 , and ZCQ scores followed a similar pattern of maintained significant improvement throughout follow-up . On the SF-12 and ZCQ , D+ILS group scores were statistically significantly better during early follow-up compared to D+PS . In the D+ILS group , foraminal height , disc space height , and range of motion at the index level were maintained through 5 years . Conclusion Both treatment groups achieved and maintained statistically significant improvements on multiple outcome assessment s throughout 5-year follow-up . On some clinical measures , there were statistically significant differences during early follow-up favoring D+ILS . At no point were there significant differences favoring D+PS . Results of this 5-year follow-up study demonstrate that decompression and interlaminar stabilization with coflex is a viable alternative to traditional decompression and fusion in the treatment of patients with moderate to severe stenosis at one or two lumbar levels . Level of Evidence and Ethical Statements This is a Level I study . Institutional approval was received at each of the sites participating in the trial . Each patient gave informed consent to participate in the trial STUDY DESIGN A cohort of 100 patients with symptomatic lumbar spinal stenosis , characterized in a previous article , were given surgical or conservative treatment and followed for 10 years . OBJECTIVES To identify the short- and long-term results after surgical and conservative treatment , and to determine whether clinical or radiologic predictors for the treatment result can be defined . SUMMARY OF BACKGROUND DATA Surgical decompression has been considered the rational treatment . However , clinical experience indicates that many patients do well with conservative treatment . METHODS In this study , 19 patients with severe symptoms were selected for surgical treatment and 50 patients with moderate symptoms for conservative treatment , whereas 31 patients were r and omized between the conservative ( n = 18 ) and surgical ( n = 13 ) treatment groups .  Pain was decisive for the choice of treatment group . All patients were observed for 10 years by clinical evaluation and question naires . The results , evaluated by patient and physician , were rated as excellent , fair , unchanged , or worse . RESULTS After a period of 3 months , relief of pain had occurred in most patients . Some had relief earlier , whereas for others it took 1 year . After a period of 4 years , excellent or fair results were found in half of the patients selected for conservative treatment , and in four fifths of the patients selected for surgery . Patients with an unsatisfactory result from conservative treatment were offered delayed  surgery  after 3 to 27 months ( median , 3.5 months ) . The treatment result of  delayed surgery  was essentially similar to that of the initial group . The treatment result for the patients r and omized for surgical treatment was considerably better than for the patients r and omized for conservative treatment . Clinical ly significant deterioration of symptoms during the final 6 years of the follow-up period was not observed . Patients with multilevel afflictions , surgically treated or not , did not have a poorer outcome than those with single-level afflictions . Clinical or radiologic predictors for the final outcome were not found . There were no dropouts , except for 14 deaths . CONCLUSIONS The outcome was most favorable for surgical treatment . However , an initial conservative approach seems advisable for many patients because those with an unsatisfactory result can be treated surgically later with a good outcome OBJECTIVE : To test the feasibility of creating a valid and reliable checklist with the following features : appropriate for assessing both r and omised and non-r and omised studies ; provision of both an overall score for study quality and a profile of scores not only for the quality of reporting , internal validity ( bias and confounding ) and power , but also for external validity . DESIGN : A pilot version was first developed , based on epidemiological principles , review s , and existing checklists for r and omised studies . Face and content validity were assessed by three experienced review ers and reliability was determined using two raters assessing 10 r and omised and 10 non-r and omised studies . Using different raters , the checklist was revised and tested for internal consistency ( Kuder-Richardson 20 ) , test-retest and inter-rater reliability ( Spearman correlation coefficient and sign rank test ; kappa statistics ) , criterion validity , and respondent burden . MAIN RESULTS : The performance of the checklist improved considerably after revision of a pilot version . The Quality Index had high internal consistency ( KR-20 : 0.89 ) as did the subscales apart from external validity ( KR-20 : 0.54 ) . Test-retest ( r 0.88 ) and inter-rater ( r 0.75 ) reliability of the Quality Index were good . Reliability of the subscales varied from good ( bias ) to poor ( external validity ) . The Quality Index correlated highly with an existing , established instrument for assessing r and omised studies ( r 0.90 ) . There was little difference between its performance with non-r and omised and with r and omised studies . Raters took about 20 minutes to assess each paper ( range 10 to 45 minutes ) . CONCLUSIONS : This study has shown that it is feasible to develop a checklist that can be used to assess the method ological quality not only of r and omised controlled trials but also non-r and omised studies . It has also shown that it is possible to produce a checklist that provides a profile of the paper , alerting 
    Output:
    
RESULTS The results of our meta- analysis showed that decompression and coflex was more effective than the control procedure in terms of the Oswestry Disability Index ( ODI ) , length of hospital stay ( LOS ) and blood loss .
However , no significant difference was found in visual analogue scale ( VAS ) and major device-related complications .
CONCLUSIONS Compared with conventional decompression plus fusion surgery , coflex was not inferior in terms of functional clinical outcomes , including ODI and VAS pain score .
Moreover , coflex showed less blood loss , shorter LOS and similar device-related complications compared to decompression plus fusion surgery .
Therefore , the coflex interlaminar stabilisation device was found to be safe and effective compared to decompression plus fusion for the treatment of LSS