***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 evaluate the effectiveness and safety of cervical arthroplasty and anterior cervical discectomy fusion methods . METHODS The r and omised clinical trial was conducted at the neurosurgical clinic of University of Harran , Turkey , between February 2009 and January 2010 . The patients had single level disc disorder between C4-C7 levels . Before surgery , all of the patients had taken medical treatment with no improvement . Surgery was conducted with anterior approach , and disc prosthesis or polyetheretherketone cage for fusion were applied after patients were r and omly divided into two groups . For preoperative and postoperative clinical evaluations Neck Disability Index and Visual Analogue Scale were used . Surgical results were evaluated according to Odom 's criterion , and ' excellent ' and ' good ' results were accepted as successful . P<0.05 was taken as statistically significant . RESULTS Of the 42 patients in the study , 23(54.76 % ) were treated with Anterior Cervical Discectomy and Fusion , and 19(45.23 % ) with Cervical Disc Arthroplasty . There were no statistical differences between postoperative mean Visual Analogue Scale score ( p<0.86 ) and Neck Disability Index scores ( p<0.11 ) in the two groups . Average decrease in lordosis angle was 1.2 degree in Arthroplasty group , while it was 1 degree in the Fusion group . Postoperative adjacent segment degeneration was not detected in either group . CONCLUSION Anterior Cervical Discectomy and Fusion , and Cervical Disc Arthroplasty are safe and successful methods for the treatment of single level cervical disc disease . Although the latter is a relatively new technique performed with increased frequency , but its superiority is still uncertain BACKGROUND CONTEXT Cervical total disc replacement ( TDR ) is intended to address radicular pain and preserve functional motion between two vertebral bodies in patients with symptomatic cervical disc disease ( SCDD ) . PURPOSE The purpose of this trial is to compare the safety and efficacy of cervical TDR , ProDisc-C ( Synthes Spine Company , L.P. , West Chester , PA ) , to anterior cervical discectomy and fusion ( ACDF ) surgery for the treatment of one-level SCDD between C3 and C7 . STUDY DESIGN / SETTING The study was conducted at 13 sites . A noninferiority design with a 1:1 r and omization was used . PATIENT SAMPLE Two hundred nine patients were r and omized and treated ( 106 ACDF ; 103 ProDisc-C ) . OUTCOME MEASURES Visual analog scale ( VAS ) pain and intensity ( neck and arm ) , VAS satisfaction , neck disability index ( NDI ) , neurological exam , device success , adverse event occurrence , and short form-36 ( SF-36 ) st and ardized question naires . METHODS A prospect i ve , r and omized , controlled clinical trial was performed . Patients were enrolled and treated in accordance with the US Food and Drug Administration ( FDA ) -approved protocol . Patients were assessed pre- and postoperatively at six weeks , 3 , 6 , 12 , 18 , and 24 months . RESULTS Demographics were similar between the two patient groups ( ProDisc-C : 42.1+/-8.4 years , 44.7 % males ; Fusion : 43.5 + /- 7.1 years , 46.2 % males ) . The most commonly treated level was C5-C6 ( ProDisc-C : 56.3 % ; Fusion=57.5 % ) . NDI and SF-36 scores were significantly less compared with presurgery scores at all follow-up visits for both the treatment groups ( p<.0001 ) . VAS neck pain intensity and frequency as well as VAS arm pain intensity and frequency were statistically lower at all follow-up timepoints compared with preoperative levels ( p<.0001 ) but were not different between treatments . Neurologic success ( improvement or maintenance ) was achieved at 24 months in 90.9 % of ProDisc-C and 88.0 % of Fusion patients ( p=.638 ) . Results show that at 24 months postoperatively , 84.4 % of ProDisc-C patients achieved a more than or equal to 4 degrees of motion or maintained motion relative to preoperative baseline at the operated level . There was a statistically significant difference in the number of secondary surgeries with 8.5 % of Fusion patients needing a re-operation , revision , or supplemental fixation within the 24 month postoperative period compared with 1.8 % of ProDisc-C patients ( p=.033 ) . At 24 months , there was a statistically significant difference in medication usage with 89.9 % of ProDisc-C patients not on strong narcotics or muscle relaxants , compared with 81.5 % of Fusion patients . CONCLUSIONS The results of this clinical trial demonstrate that ProDisc-C is a safe and effective surgical treatment for patients with disabling cervical radiculopathy because of single-level disease . By all primary and secondary measures evaluated , clinical outcomes after ProDisc-C implantation were either equivalent or superior to those same clinical outcomes after Fusion OBJECT The authors report the results of a prospect i ve r and omized multicenter study in which the results of cervical disc arthroplasty were compared with anterior cervical discectomy and fusion ( ACDF ) in patients treated for symptomatic single-level cervical degenerative disc disease ( DDD ) . METHODS Five hundred forty-one patients with single-level cervical DDD and radiculopathy were enrolled at 32 sites and r and omly assigned to one of two treatment groups : 276 patients in the investigational group underwent anterior cervical discectomy and decompression and arthroplasty with the PRESTIGE ST Cervical Disc System ( Medtronic Sofamor Danek ) ;  265 patients in the control group underwent decompressive ACDF . Eighty percent of the arthroplasty-treated patients ( 223 of 276 ) and 75 % of the control patients ( 198 of 265 ) completed clinical and radiographic follow-up examinations at routine intervals for 2 years after surgery . Analysis of all currently available postoperative 12- and 24-month data indicated a two-point greater improvement in the neck disability index score in the investigational group than the control group . The arthroplasty group also had a statistically significant higher rate of neurological success ( p = 0.005 ) as well as a lower rate of secondary revision surgeries ( p = 0.0277 ) and supplemental fixation ( p = 0.0031 ) . The mean improvement in the 36-Item Short Form Health Survey Physical Component Summary scores was greater in the investigational group at 12 and 24 months , as was relief of neck pain . The patients in the investigational group returned to work 16 days sooner than those in the control group , and the rate of adjacent-segment reoperation was significantly lower in the investigational group as well ( p = 0.0492 , log-rank test ) . The cervical disc implant maintained segmental sagittal angular motion averaging more than 7 degrees . In the investigational group , there were no cases of implant failure or migration . CONCLUSIONS The PRESTIGE ST Cervical Disc System maintained physiological segmental motion at 24 months after implantation and was associated with improved neurological success , improved clinical outcomes , and a reduced rate of secondary surgeries compared with ACDF OBJECT There are now 3 r and omized , multicenter , US FDA investigational device exemption , industry-sponsored studies comparing arthroplasty with anterior cervical discectomy and fusion ( ACDF ) for single-level cervical disease with 2 years of follow-up . These 3 studies evaluated the Prestige ST , Bryan , and ProDisc-C artificial discs . The authors analyzed the combined results of these trials . METHODS A total of 1213 patients with symptomatic , single-level cervical disc disease were r and omized into 2 treatment arms in the 3 r and omized trials . Six hundred twenty-one patients received an artificial cervical disc , and 592 patients were treated with ACDF .  In the three trials , 94 % of the arthroplasty group and 87 % of the ACDF group have completed 2 years of follow-up . The authors analyzed the 2-year data from these 3 trials including previously unpublished source data . Statistical analysis was performed with fixed and r and om effects models . RESULTS The authors ' analysis revealed that segmental sagittal motion was preserved with arthroplasty ( preoperatively 7.26 ° and postoperatively 8.14 ° ) at the 2-year time point . The fusion rate for ACDF at 2 years was 95 % . The Neck Disability Index , 36-Item Short Form Health Survey Mental , and Physical Component Summaries , neck pain , and arm pain scores were not statistically different between the groups at the 24-month follow-up . The arthroplasty group demonstrated superior results at 24 months in neurological success ( RR 0.595 , I(2 ) = 0 % , p = 0.006 ) . The arthroplasty group had a lower rate of secondary surgeries at the 2-year time point ( RR 0.44 , I(2 ) = 0 % , p = 0.004 ) . At the 2-year time point , the reoperation rate for adjacent-level disease was lower for the arthroplasty group when the authors analyzed the combined data set using a fixed effects model ( RR 0.460 , I(2 ) = 2.9 % , p = 0.030 ) , but this finding was not significant using a r and om effects model . Adverse event reporting was too heterogeneous between the 3 trials to combine for analysis . CONCLUSIONS Both anterior cervical discectomy and fusion as well as arthroplasty demonstrate excellent 2-year surgical results for the treatment of 1-level cervical disc disease with radiculopathy . Arthroplasty is associated with a lower rate of secondary surgery and a higher rate of neurological success at 2 years . Arthroplasty may be associated with a lower rate of adjacent-level disease at 2 years , but further follow-up and analysis are needed to confirm this finding Purpose Heterotopic ossification is a phenomenon in cervical arthroplasty . Previous reports have mainly focused on various semiconstrained devices and only a few publications have focused on ossification around devices that are nonconstrained . The purpose of this study was to assess the occurrence of heterotopic ossification around a nonconstrained cervical device and how it affects clinical outcome 2 years after surgery . Methods Thirty-seven patients were included from a larger cohort of a r and omized controlled trial ( NORCAT ) which compared single-level cervical arthroplasty with fusion .  The occurrence of heterotopic ossification was assessed with a CT scan and two neuroradiologists determined its degree . For grading , we used the Mehren/Suchomel classification system ( grade 0–4 ) . The patients were divided by level of ossification , low grade ( 0–2 ) or high grade ( 3–4 ) , and clinical outcomes were compared . Self-rated disability for neck and arm pain ( Neck Disability Index ) , health-related quality of life ( the Short Form-36 and EuroQol-5D ) , and pain ( the Numeric Rating Scale 11 ) were used as clinical outcome measures . Results Heterotopic ossification was encountered in all patients 2 years after surgery . Complete fusion ( grade 4 ) was found in 16 % of participants , and high- grade ossification ( grade 3–4 ) occurred in 62 % . The remaining patients were classified as having low- grade ossification ( grade 2 ) . There were no differences in the clinical outcomes of patients with low- and high- grade ossification . Conclusion High- grade heterotopic ossification and spontaneous fusion 2 years after surgery were seen in a significant number of patients . However , the degree of ossification did not influence the clinical outcome Purpose St and ard surgical treatment for symptomatic cervical disc disease has been discectomy and fusion , but the use of arthroplasty , design ed to preserve motion , has increased , and most studies report clinical outcome in its favor . Few of these trials , however , blinded the patients . We , therefore , conducted the Norwegian Cervical Arthroplasty Trial , and present 2-year clinical outcome after arthroplasty or fusion . Methods This multicenter trial included 136 patients with single-level cervical disc disease . The patients were r and omized to arthroplasty or fusion , and blinded to the treatment modality . The surgical team was blinded to r and omization until nerve root decompression was completed . Primary outcome was the self-rated Neck Disability Index . Secondary outcomes were the numeric rating scale for pain and quality of life question naires Short Form-36 and EuroQol-5Dimension-3 Level . Results There was a significant improvement in the primary and all secondary outcomes from baseline to 2-year follow-up for both arthroplasty and fusion ( P < 0.001 ) , and no observed significant between-group differences at any follow-up times . However , linear mixed model analyses , correcting for baseline values , dropouts and missing data , revealed a difference in Neck Disability Index ( P = 0.049 ) , and arm pain ( P = 0.027 ) in favor of fusion at 2 years . The duration of surgery was longer ( P < 0.001 ) , and the frequency of reoperations higher ( P = 0.029 ) with arthroplasty . Conclusion The present study showed excellent clinical results and no significant difference between treatments at any scheduled follow-up . However , the rate of index level reoperations was higher and the duration of surgery longer with arthroplasty 
    Output:
    
Conclusions : There is a lack of consistency in reporting of AEs among RCTs of cervical arthroplasty .
FDA IDE trials scored better in AE event reporting compared to other studies .