***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: BACKGROUND AND OBJECTIVE To develop a checklist of items measuring the quality of reports of r and omized clinical trials ( RCTs ) assessing nonpharmacological treatments ( NPTs ) . STUDY DESIGN AND SETTING The Delphi consensus method was used to select and reduce the number of items in the checklist . A total of 154 individuals were invited to participate : epidemiologists and statisticians involved in the field of methodology of RCTs ( n = 55 ) , members of the Cochrane Collaboration ( n = 41 ) , and clinicians involved in planning NPT clinical trials ( n = 58 ) . Participants ranked on a 10-point Likert scale whether an item should be included in the checklist . RESULTS Fifty-five experts ( 36 % ) participated in the survey . They were experienced in systematic review s ( 68 % were involved in the Cochrane Collaboration ) and in planning RCTs ( 76 % ) . Three rounds of the Delphi method were conducted to achieve consensus . The final checklist contains 10 items and 5 subitems , with items related to the st and ardization of the intervention , care provider influence , and additional measures to minimize the potential bias from lack of blinding of participants , care providers , and outcome assessors . CONCLUSIONS This tool can be used to critically appraise the medical literature , design NPT studies , and assess the quality of trial reports included in systematic review Study Design . A prospect i ve , r and omized , multicenter , Food and Drug Administration-regulated Investigational Device Exemption clinical trial . Objective . To evaluate the safety and effectiveness of the ProDisc ® -L ( Synthes Spine , West Chester , PA ) lumbar total disc replacement compared to circumferential spinal fusion for the treatment of discogenic pain at 1 vertebral level between L3 and S1 . Summary of Background Data . As part of the Investigational Device Exemption clinical trial , favorable single center results of lumbar total disc replacement with the ProDisc ® -L have been reported previously . Methods . Two hundred eighty-six ( 286 ) patients were treated on protocol . Patients were evaluated before and after surgery , at 6 weeks , 3 , 6 , 12 , 18 , and 24 months . Evaluation at each visit included patient self- assessment s , physical and neurologic examinations , and radiographic evaluation . Results . Safety of ProDisc ® -L implantation was demonstrated with 0 % major complications . At 24 months , 91.8 % of investigational and 84.5 % of control patients reported improvement in the Oswestry Low Back Pain Disability Question naire ( Oswestry Disability Index [ ODI ] ) from preoperative levels , and 77.2 % of investigational and 64.8 % of control patients met the ≥15 % Oswestry Disability Index improvement criteria . Overall neurologic success in the investigational group was superior to the control group ( 91.2 % investigational and 81.4 % control ; P = 0.0341 ) . At 6 weeks and 3 months follow-up time points , the ProDisc ® -L patients recorded SF-36 Health Survey scores significantly higher than the control group ( P = 0.018 , P = 0.0036 , respectively ) . The visual analog scale pain assessment showed statistically significant improvement from preoperative levels regardless of treatment ( P < 0.0001 ) . Visual analog scale patient satisfaction at 24 months showed a statistically significant difference favoring investigational patients over the control group ( P = 0.015 ) . Radiographic range of motion was maintained within a normal functional range in 93.7 % of investigational patients and averaged 7.7 ° . Conclusions . ProDisc ® -L has been found to be safe and efficacious . In properly chosen patients , ProDisc ® -L has been shown to be superior to circumferential fusion by multiple clinical criteria Background The objective of this clinical study is to evaluate the safety and effectiveness of the Activ-L Artificial Disc for treatment of single-level degenerative disc disease of the lumbar spine in patients who have been unresponsive to at least six months of prior conservative care . The hypothesis of the study is that the Activ-L Disc is non-inferior to the control ( the Charité ® Artificial Disc [ DePuy Spine ] or ProDisc-L ® Total Disc Replacement [ Synthes Spine ] ) with respect to the rate of individual subject success at 24 months . Individual subject success is a composite of effectiveness and safety . Methods / Design The study proposed is a prospect i ve , r and omized , single-masked , controlled , multi-center clinical trial consisting of an estimated 414 subjects with single-level DDD of the lumbar spine ( L4/L5 , or L5/S1 ) who have failed to improve with conservative treatment for at least six months prior to enrollment . After enrollment , subjects will be r and omized in a 2:1 ratio to either the Activ-L Disc ( investigational device ) or the control ( Charité or ProDisc-L ) . Radiographic endpoints will be evaluated by an independent review er at an imaging core laboratory . Each subject will be followed for 5 years post-treatment . Discussion The safety and effectiveness of the Activ-L Artificial Disc for treatment of single-level degenerative disc disease of the lumbar spine will be equivalent to Charité ® Artificial Disc [ DePuy Spine ] or ProDisc-L ® Total Disc Replacement [ Synthes Spine ] at 24 months . Trial Registration Current Controlled Trials NCT00589797 Study Design . Prospect i ve study analyzing midterm clinical results of  total lumbar disc replacement ( ProDisc II )  for different indications . Objectives . To assess functional outcome after total lumbar disc replacement ( TDR )  treated for varying indications . Summary of Background Data . Despite its frequent use and increasing popularity , indications and contraindications for TDR have not been defined precisely at this stage and remain a matter of debate , leading to disc replacement procedures in a variety of pathologies that have not yet been evaluated and compared separately . Methods . Patients meeting inclusion criteria were evaluated prospect ively according to Visual Analogue Scale ( VAS ) , Oswestry Question naire , SF-36 , and numerous clinical parameters . Indications included degenerative disc disease ( DDD ) , DDD with accompanying soft disc herniation ( nucleus pulposus prolapse , NPP ) , osteochondrosis following previous discectomy , and DDD with presence of Modic changes . Postoperative improvement was recorded and analyzed for influence of preoperative diagnosis . Results . Overall , 92 patients from four groups with a mean follow-up of 34.2 months ( minimum , 24 months ) achieved significant and maintained improvement from preoperative levels ( P < 0001 ) . Patients with DDD + NPP achieved results significantly better than patients from the other groups ( P < 0.05 ) . Presence of Modic changes or previous discectomy did not influence outcome negatively . Improvement was achieved for both monosegmental and bisegmental disc replacements ( P < 0.05 ) , nevertheless with significantly inferior results for bisegmental interventions at 12- and 24-month follow-up and considerably higher complication rate . While older patients were still highly satisfied with postoperative outcome , better functional outcome was observed in younger patients . Conclusion . Present data suggest beneficial clinical results of TDR for treatment of DDD in a highly selected group of patients . Better functional outcome was obtained in younger patients under 40 years of age and patients with degenerative disc disease in association with disc herniation . Multilevel disc replacement had significantly higher complication rate and inferior outcome . Results are significantly dependent on preoperative diagnosis and patient selection , number of replaced segments , and age of the patient at the time of operation . Because of significantly varying outcomes , indications for disc replacement must be defined precisely Background Difficulties in performing r and omized controlled trials ( RCTs ) to evaluate new treatment options are increasing . Higher costs and patient unwillingness are the main obstacles . A  spinal surgery register  has been in use in Sweden for 11 years . Our aim was to determine whether this register can provide the same information as an RCT and whether register data compare favorably with RCT data , making RCTs unnecessary . If not the case , was patient selection or follow-up frequency the cause of any differences ? Material s and methods We compared baseline data and outcome , retrieved from our register , between 2 surgical groups , total disc replacement ( TDR ) and fusion at 1 or 2 levels , performed for degenerative disc disease . One hundred fifty-two patients were part of an RCT , whereas four hundred fifty-five patients had been treated according to an active decision . These 2 subgroups were the subjects for comparison . Results The 2 subgroups were not similar at baseline . Patients who were fused in the non- RCT subgroup were older , had a higher Oswestry Disability Index , and were more frequently smokers than the other patients . The outcome for the non- RCT group showed larger differences in favor of TDR than the RCT did . The nonresponders in the non- RCT group showed worse life quality and disability at baseline , and patients who answered the 1-year follow-up question naire but not the 2-year follow-up question naire had an inferior clinical result compared with the other patients at 1 year . Conclusion Data from our register showed results similar to the RCT , but a register can not fully replace an RCT study when evaluating a new treatment option if the RCT has narrower selection than just the diagnosis . In this RCT comparing TDR with posterior fusion , the normal exclusion criteria for TDR were used . These were not registered , so the register could not prevent a possible selection bias , which might also be caused by the nonresponders Study Design . Radiographic results from a prospect i ve , r and omized , multicenter trial assessing patients who underwent lumbar total disc replacement ( TDR ) or circumferential arthrodesis for 1-level degenerative disc disease . Objective . To quantify the relative segmental contribution to total lumbar range of motion ( ROM ) at the operative level at each adjacent level in lumbar TDR and arthrodesis . Summary of Background Data . Although previous studies have evaluated ROM in TDR and fusion , no study has quantified or compared the relative segmental contribution to total lumbar ROM . Further , no study to the best of our knowledge has evaluated the kinematic profile of the more cranial adjacent segments ( i.e. , the second or third adjacent levels ) following implantation of either TDR or fusion . Methods . Radiographic data collected from all r and omized 1-level degenerative disc disease patients operated at L4/5 or L5/S1 that participated in the multicenter , prospect i ve , r and omized IDE study comparing ProDisc-L with circumferential lumbar arthrodesis were evaluated before surgery and at 24 months . Radiographic measurements were performed independently using custom digitized image stabilization software to generate ROM at the operative level , and at each cranial and caudal adjacent level . Results . There were 200 total patients included ( 155 ProDisc-L , average age 39 years ; 45 arthrodesis , average age 40 years ) . At 24 months , the L4/5 TDR group experienced a significant improvement in total lumbar ROM from baseline ( + 6.3 ° ) , whereas there was no change seen with L5/S1 TDR or any fusion group . Between-group comparisons from baseline to 24 months postoperatively revealed : ( 1 ) significantly more contribution from the operative level towards total lumbar range in TDR  at operative level L4/5 ( TDR : −2.5 % , fusion : −16.8 % , P = 0.006 ) , and operative level L5/S1 ( TDR : −5.1 % , fusion : −15.9 % , P < 0.001 ) , and ( 2 ) the relative contribution towards total lumbar range of motion from the first cranial adjacent segment to fusion at L5/S1 increased by 12.1 % , compared with −1.2 % seen in TDR ( P = 0.03 ) . There were elevated contributions from the more cranial adjacent levels to a fusion when compared with TDR , however , these differences were not statistically significant . At operative level L4/5 , there was significantly increased ROM from the first caudal segment below TDR ( 6 % , P = 0.03 ) , but not below fusion ( 3.1 % , P = 0.59 ) . Conclusion . In conclusion , patients with TDR lost slight relative contribution to total lumbar motion from the operative level which was mostly compensated for by the caudal adjacent level ( if operated at L4/5 ) . In contrast , the significant loss of relative range of motion contribution from the operative level in fusions was redistributed among multiple cranial adjacent levels , most notably at the first cranial adjacent level Sixty patients with one-level discogenic pain confirmed by plain radiography , magnetic resonance imaging , and provocative discography for degenerative disc disease were r and omized : one-third BAK anterior interbody fusion and two-thirds anterior SB Charité artificial disc replacement . The mean age was 40.3 years ( range 21 - 56 years ) . Nineteen cases were at L4-L5 and 41 cases were at L5-S1 . Nineteen cases had BAK anterior interbody fusion and 41 cases were r and omized as SB Charité disc replacement . The length of surgery was mean 88.4 minutes ( range 54 - 137 minutes ) for both groups . The estimated blood loss was mean 289.5 mL ( range 50 - 1800 mL ) . The length of hospital stay was a mean of 3.03 days ( range 2 - 6 days ) . Oswestry Disability Index scores for the SB Charité disc ( aggregate study group ) were 50.0 + /- 14.3 preoperatively and 25.0 + /- 20.1 at 1 - 3 years ' follow-up ( P < 0.001 ) . This is the first study that shows improvement of functional outcome measures in a prospect i ve r and omized design with disc arthroplasty treating primarily mechanical back pain and achieving comparable successful results to lumbar fusion-interbody fusion cage and BMP or interbody autograft and pedicle screw instrumentation OBJECT A secondary lumbar 
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Choice of control group ( circumferential or anterior fusion ) did not appear to result in different outcomes .
AUTHORS ' CONCLUSIONS Although statistically significant , the differences between disc replacement and conventional fusion surgery for degenerative disc disease were not beyond the generally accepted clinical important differences with respect to short-term pain relief , disability and Quality of Life .
Therefore , because we believe that harm and complications may occur after years , we believe that the spine surgery community should be prudent about adopting this technology on a large scale , despite the fact that total disc replacement seems to be effective in treating  low-back pain in selected patients , and in the short term is at least equivalent to fusion surgery