***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 
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    Input: Study Design . Single blind r and omized study . Objectives . To compare the effectiveness of  lumbar instrumented fusion with cognitive intervention and exercises in patients with chronic low back pain and disc degeneration . Summary of Background Data . To the authors ’ best knowledge , only one r and omized study has evaluated the effectiveness of lumbar fusion . The Swedish Lumbar Spine Study reported that lumbar fusion was better than continuing physiotherapy and care by the family physician . Patients and Methods . Sixty-four patients aged 25–60 years with low back pain lasting longer than 1 year and evidence of disc degeneration at L4–L5 and /or L5–S1 at radiographic examination were r and omized to either lumbar fusion with posterior transpedicular screws and postoperative physiotherapy , or cognitive intervention and exercises . The cognitive intervention consisted of a lecture to give the patient an underst and ing that ordinary physical activity would not harm the disc and a recommendation to use the back and bend it . This was reinforced by three daily physical exercise sessions for 3 weeks . The main outcome measure was the Oswestry Disability Index . Results . At the 1-year follow-up visit , 97 % of the patients , including 6 patients who had either not attended treatment or changed groups , were examined . The Oswestry Disability Index was significantly reduced from 41 to 26 after surgery , compared with 42 to 30 after cognitive intervention and exercises . The mean difference between groups was 2.3 ( −6.7 to 11.4 ) ( P = 0.33 ) . Improvements inback pain , use of analgesics , emotional distress , life satisfaction , and return to work were not different . Fear-avoidance beliefs and fingertip-floor distance were reduced more after nonoperative treatment , and lower limb pain was reduced more after surgery . The success rateaccording to an independent observer was 70 % after surgery and 76 % after cognitive intervention and exercises .  The early complication rate in the surgical group was 18 % . Conclusion . The main outcome measure showed equal improvement in patients with chronic low back pain and disc degeneration r and omized to cognitive intervention and exercises , or lumbar fusion BACKGROUND Management of degenerative spondylolisthesis with spinal stenosis is controversial . Surgery is widely used , but its effectiveness in comparison with that of nonsurgical treatment has not been demonstrated in controlled trials . METHODS Surgical c and i date s from 13 centers in 11 U.S. states who had at least 12 weeks of symptoms and image-confirmed degenerative spondylolisthesis were offered enrollment in a  r and omized cohort or an  observational cohort . Treatment was st and ard decompressive laminectomy ( with or without fusion ) or usual nonsurgical care . The primary outcome measures were the Medical Outcomes Study 36-Item Short-Form General Health Survey ( SF-36 ) bodily pain and physical function scores ( 100-point scales , with higher scores indicating less severe symptoms ) and the modified Oswestry Disability Index ( 100-point scale , with lower scores indicating less severe symptoms ) at 6 weeks , 3 months , 6 months , 1 year , and 2 years . RESULTS We enrolled 304 patients in the r and omized cohort and 303 in the observational cohort . The baseline characteristics of the two cohorts were similar . The one-year crossover rates were high in the r and omized cohort ( approximately 40 % in each direction ) but moderate in the observational cohort ( 17 % crossover to surgery and 3 % crossover to nonsurgical care ) . The intention-to-treat analysis for the r and omized cohort showed no statistically significant effects for the primary outcomes . The as-treated analysis for both cohorts combined showed a significant advantage for surgery at 3 months that increased at 1 year and diminished only slightly at 2 years . The treatment effects at 2 years were 18.1 for bodily pain ( 95 % confidence interval [ CI ] , 14.5 to 21.7 ) , 18.3 for physical function ( 95 % CI , 14.6 to 21.9 ) , and -16.7 for the Oswestry Disability Index ( 95 % CI , -19.5 to -13.9 ) . There was little evidence of harm from either treatment . CONCLUSIONS In nonr and omized as-treated comparisons with careful control for potentially confounding baseline factors , patients with degenerative spondylolisthesis and spinal stenosis treated surgically showed substantially greater improvement in pain and function during a period of 2 years than patients treated nonsurgically . ( Clinical Trials.gov number , NCT00000409 [ Clinical Trials.gov ] . ) Abstract . The reported complication rates after various surgical techniques used to create a lumbar fusion vary within wide ranges . In a previous paper , the Swedish Lumbar Spine Study Group have reported on the clinical outcome of lumbar spine fusion for chronic low back pain in a comparably homogeneous patient population where there were no significant differences between baseline sociodemographic , clinical and para clinical characteristics . In this report we compared the complication rates of the surgical procedures used in that study and analyzed the association between complications and baseline variables , and between outcome results and complications . A multicenter r and omized study was conducted where 211 patients aged 25–65 were treated with lumbar fusion according to three different surgical techniques : noninstrumented posterolateral fusion ( PLF , n=71 ) , instrumented posterolateral fusion ( VSP , n=68 ) , and in the third procedure we added an interbody fusion with solid autogenous bone grafts ( " 360 " , n=72 ) . We categorized complications as : early/late , major/minor . The association between complications and sociodemographic characteristics ( age , gender , comorbidity , previous surgery , smoking ) , and technical variables ( surgical technique , levels fused , hospital category ) was analyzed . The association between outcome variables ( patient global assessment , pain , disability , depressive symptoms ) and complications was analyzed . A literature review was conducted . There was no mortality . There was no significant difference in clinical outcome between the surgical groups after 2 years , although the power to detect such a difference was low . The total complication rate after 2 years in the PLF group was 12 % , compared with 22 % in the VSP group , and 40 % in the " 360 " group ( P=0.0003 ) . After exclusion of complications , there was still no difference in outcome between the groups . The odds ratio ( confidence intervals ) of having a complication was 5.3 ( 2.2–12.7 ) when " 360 " was used compared with PLF , and 2.4 ( 1.1–5.3 ) for " 360 " compared with VSP . There was no association between clinical outcome and complications on a group level . The reintervention rate was 6 % in the PLF group , 22 % in the VSP , and 17 % in the " 360 " group ( P=0.020 ) . The odds ratio ( confidence intervals ) of having a reintervention was 4.0 ( 1.3–11.9 ) when instrumentation was used compared with non-instrumented fusion . In this prospect i ve r and omized study comparing three  lumbar fusion techniques  in a comparably homogeneous patient population , complications increased significantly with increasing technicality of the surgical procedure . Even though we did not find a significant association between clinical outcome and complications after 2 years , the increased morbidity inflicted on an individual patient was not negligible . In this light , and as no fusion technique produced superior clinical outcome irrespective of whether complications were included or excluded in the analyses , the patient and the treating physician should carefully discuss the possible advantages and drawbacks of the different surgical options before making a decision . In order to make valid comparisons of both complication and reintervention rates after lumbar fusion , there is a need for a consensus in the spinal society regarding the definition of these entities Background Decompressive laminotomy is the st and ard surgical procedure in the treatment of patients with canal stenosis related intermittent neurogenic claudication . New techniques , such as interspinous process implants , cl aim a shorter hospital stay , less post-operative pain and equal long-term functional outcome . A comparative ( cost- ) effectiveness study has not been performed yet . This protocol describes the design of a r and omized controlled trial ( RCT ) on ( cost- ) effectiveness of the use of interspinous process implants versus conventional decompression surgery in patients with lumbar spinal stenosis . Methods / Design Patients ( age 40 - 85 ) presenting with intermittent neurogenic claudication due to lumbar spinal stenosis lasting more than 3 months refractory to conservative treatment , are included . R and omization into interspinous implant surgery versus bony decompression surgery will take place in the operating room after induction of anesthesia . The primary outcome measure is the functional assessment of the patient measured by the Zurich Claudication Question naire ( ZCQ ) , at 8 weeks and 1 year after surgery . Other outcome parameters include perceived recovery , leg and back pain , incidence of re-operations , complications , quality of life , medical consumption , absenteeism and costs . The study is a r and omized multi-institutional trial , in which two surgical techniques are compared in a parallel group design . Patients and research nurses are kept blinded of the allocated treatment during the follow-up period of 1 year . Discussion Currently decompressive laminotomy is the golden st and ard in the surgical treatment of lumbar spinal stenosis . Whether surgery with interspinous implants is a reasonable alternative can be determined by this trial . Trial registerDutch Trial register number : We prospect ively evaluated the results of decompression of the spine , with and without arthrodesis , for the treatment of lumbar spinal stenosis without instability in forty-five patients ( twenty-one men and twenty-four women ) who had been managed between November 1989 and November 1990 . The average age at the time of the operation was sixty-seven years ( range , forty-eight to eighty-seven years ) . The patients were r and omly assigned to one of three treatment groups ( fifteen patients in each group ) according to when they were admitted to the hospital . Group I was treated with decompression with laminotomy and medial facetectomy ; Group II , with decompression and arthrodesis of the most stenotic segment ; and Group III , with decompression and arthrodesis of all of the decompressed vertebral segments . All of the operations were performed by the same surgeon . The average duration of follow-up was twenty-eight months ( range , twenty-four to thirty-two months ) . All three groups had a significant improvement in the distance that the patients were able to walk at the time of the latest follow-up examination compared with before the operation ( p < 0.001 for Group I , p < 0.002 for Group II , and p < 0.005 for Group III ) . With the numbers available , there were no significant differences in the results among the three groups with regard to the relief of pain ( p = 0.25 for Group I compared with Group II , p = 0.36 for Group II compared with Group III , and p = 0.92 for Group I compared with Group III ) . ( ABSTRACT TRUNCATED AT 250 WORDS BACKGROUND Lumbar-disk surgery often is performed in patients who have sciatica that does not resolve within 6 weeks , but the optimal timing of surgery is not known . METHODS We r and omly assigned 283 patients who had had severe sciatica for 6 to 12 weeks to early surgery  or to prolonged conservative treatment with surgery if needed . The primary outcomes were the score on the Rol and Disability Question naire , the score on the visual-analogue scale for leg pain , and the patient 's report of perceived recovery during the first year after r and omization . Repeated- measures analysis according to the intention-to-treat principle was used to estimate the outcome curves for both groups . RESULTS Of 141 patients assigned to undergo early surgery  , 125 ( 89 % ) underwent  microdiskectomy  after a mean of 2.2 weeks . Of 142 patients design ated for conservative treatment , 55 ( 39 % ) were treated surgically after a mean of 18.7 weeks . There was no significant overall difference in disability scores during the first year ( P=0.13 ) . Relief of leg pain was faster for patients assigned to early surgery ( P<0.001 ) . Patients assigned to early surgery also reported a faster rate of perceived recovery ( hazard ratio , 1.97 ; 95 % confidence interval , 1.72 to 2.22 ; P<0.001 ) . In both groups , however , the probability of perceived recovery after 1 year of follow-up was 95 % . CONCLUSIONS The 1-year outcomes were similar for patients assigned to early surgery and those assigned to conservative treatment with eventual surgery if needed , but the rates of pain relief and of perceived recovery were faster for those assigned to early surgery . ( Current Controlled Trials number , IS RCT N26872154 [ controlled-trials.com ] . ) Summary of Background Data . The Spine Patient Outcomes Research Trial ( SPORT ) was design ed to assess the relative efficacy and cost-effectiveness of  surgical and nonsurgical approaches to the treatment of common conditions associated with low back and leg pain . Objectives . To describe the rationale and design of the SPORT project and to discuss its strengths and limitations . Study Design . Descriptive . Methods . First , the authors explain the rationale for embarking on SPORT , i.e. , deficiencies in the existing scientific knowledge base for treatment of these conditions . Second , the authors describe the design of SPORT , including topics such as specific aims , participating sites , study population , recruitment and enrollment , study interventions , follow-up , outcomes , statistical analysis , and study governance and organization . Finally , issues that complicate the performance of r and omized trials 
    Output:
    
In all the studies , surgery showed better results for pain , disability , and quality of life , although not for walking ability .
Results of surgery were similar among patients with and without spondylolisthesis , and slightly better among those with neurogenic claudication than among those without it .
In patients with symptomatic LSS , the implantation of a specific type of device or decompressive surgery , with or without fusion , is more effective than continued conservative treatment when the latter has failed for 3 to 6 months