***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: In ventral fusion after anterior cervical discectomy there is still a remarkable number of cage subsidence and segmental kyphosis seen . The aim of the present study is to assess whether the cage design influences the extent of correction loss during follow-up . Sixty patients with single-level cervical disc herniation were r and omly treated with two different cervical inter-body cages ( group1 : Solis ™ cage , Stryker Company and group2 : Shell ™ cage , AMT Company ) . Clinical and radiological follow-up was done before and after surgery , 3 and 6 months post-surgery . Clinical follow-up was done with the help of Odom ’s criteria . Both groups were similar in the baseline parameters ( age , sex , treated level ) . Statistically , the subsidence was significantly higher at 3 and 6-month follow-ups in group1 than in group2 , however , clinical results showed no significant differences . In 67 % , subsidence was seen in the anterior lower aspect of the treated segment . Segmental kyphosis was seen in seven patients of group1 and two patients of group2 . A significant correlation is found between Odom ’s criteria and subsidence . Although there was no significant difference in a short-term clinical result between the two treatment groups , we recommend the use of cages which preserve the determined segmental height and lordosis Study Design . A question naire was mailed to 3000 r and omly selected 35‐45‐year‐old individuals in three communities in central Sweden . Objectives . To study the 1‐year prevalence of spinal pain and its ramifications in the form of pain , function , sick leave , and health care use . Summary of Background Data . Previous research ers have used a variety of definitions and population s , but primarily have investigated the occurrence of pain . Comprehensive data are needed concerning health care use , the degree of the pain problem , functional disturbances , and sick leave . Method . Participants in the study completed a question naire regarding spinal pain during the past year including the degree of their experienced pain , functional impairment , lost work days , and health care use . Results . A total of 2305 people ( 78.5 % ) responded to the question naire . Nonrespondents had similar characteristics but a slightly lower 1‐year prevalence rate than did respondents . For respondents , the prevalence of spinal pain during the past year was 66.3 % , with women having a slightly higher prevalence than men . Approximately 25 % of the respondents indicated that they had a substantial problem based on ratings of pain , functional impairment , and sick leave . Work absenteeism reported to the Public Social Insurance Office involved 19 % of those with pain , but an additional 15 % indicated unreported absenteeism . On average , those with pain visited health care providers three times during the past year , but a small number of those who experienced pain consumed large amounts of health care and illness benefits . An important gender difference was shown , such that when pain was at its worst , men took sick leave , whereas women sought health care . Conclusions . Taken together , these data indicate that spinal pain is common among 35‐45‐year‐old men and ‐ women , and that it is related to marked problems for approximately one fourth of those who experience pain . Gender differences exist in the pattern of sick leave and health care use , and a small proportion of those with pain consume very large amounts of the re sources . Consequently , there is a need for early , effective , preventive treatments 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 The authors compare clinical outcome and fusion rates after iliac crest autograft (ICAG)- and rectangular titanium cage (RTC)-augmented fusion in patients undergoing anterior cervical discectomy ( ACD ) . METHODS One hundred consecutive patients with 127 levels of cervical disc disease refractory to conservative treatment were r and omized into one of the two treatment groups ( ICAG/RTC fusion ) . The visual analog scale was used by the patient to rate overall pain and head , neck , arm , and donor site pain separately . Myelopathy was documented according to Japanese Orthopaedic Association and Nurick grading systems . Outcome was analyzed using Odom criteria , the 36-Item Short Form ( SF-36 ) , and Patient Satisfaction Index scales . Fusion rates were assessed on st and ard and flexion-extension radiographs . Follow-up data of at least 12 months ' duration were available for 95 patients . More residual overall pain after 12 months was documented in patients who underwent ICAG fusion ( 3.3 + /- 2.5 [ ICAG ] and 2.2 + /- 2.4 [ RTC ] ; p < 0.05 ) . Although arm and head pain were minimal in both groups , neck pain proved to be the predominant symptom ( 2.7 + /- 2.5 [ ICAG ] and 1.9 + /- 2.1 [ RTC ] ) , which resolved in only 67 and 48 % of RTC- and ICAG-treated patients , respectively ( p < 0.05 ) . Myelopathy improved comparably in both groups . Regardless of increased pain in ICAG-treated patients , PSI and SF-36 scores were not significantly different between groups ( only four [ 8 % ] of 47 ICAG-treated patients and five [ 10 % ] of 48 RTC-treated patients were unsatisfied ) . Good to excellent functional recovery according to Odom criteria was observed in 75 and 79 % of ICAG- and RTC-treated patients , respectively . Fusion rates were 81 and 74 % , respectively ( p = 0.51 ) . CONCLUSIONS Fusion rates and clinical outcome at 12 months after ACD were comparable between patients who underwent ICAG and RTC fusion . The use of rectangular cages , however , avoids donor site morbidity and reduces overall pain and , thus , seems to be an advantageous treatment alternative BACKGROUND : Sagittal alignment of the cervical spine has received increased attention in the literature as an important determinant of clinical outcomes after anterior cervical diskectomy and fusion . Surgeons use parallel or lordotically fashioned grafts depending on preference or simple availability . OBJECTIVE : To quantitatively assess and compare cervical sagittal alignment and clinical outcome when lordotic or parallel allografts were used for fusion . METHODS : A prospect i ve , r and omized , double-blind clinical study that enrolled 122 patients was performed . The mean follow-up was 37.5 months ( range , 12 - 54 months ) . RESULTS : The mean postoperative cervical sagittal alignment was 19 ° ( range , −7 ° -36 ° ) and 18 ° ( range , −7 ° -37 ° ) in the lordotic and parallel graft patient groups , respectively . The mean segmental sagittal alignment was 6 ° ( range , −4 ° -19 ° ) and 7 ° ( range , −3 ° -19 ° ) in the lordotic and parallel graft patient groups , respectively . There were no statistically significant differences in clinical outcome scores between the lordotic and parallel graft patient groups . However , patients who had maintained or improved segmental sagittal alignment , regardless of graft type , achieved a higher degree of improvement in Short Form-36 Physical Component Summary and Neck Disability Index scores . This was statistically significant ( P < .038 ) . CONCLUSION : The use of lordotically shaped allografts does not increase cervical/segmental sagittal alignment or improve clinical outcomes . Maintaining a consistent segmental sagittal alignment or increasing segmental lordosis was related to a higher degree of improvement in clinical outcomes Study Design . R and omized controlled study . Objective . To compare the rates of adverse events associated with disc arthroplasty versus those of anterior cervical discectomy and arthrodesis with allograft and plate . Summary of Background Data . Cervical disc arthroplasty as a substitute for fusion has been developed to maintain motion and , theoretically , prevent adjacent segment degeneration . Currently , cervical arthroplasty devices are undergoing clinical testing for safety and efficacy . The evaluation of safety is performed by critical analysis of all adverse occurrences following surgery to determine if the new device has a beneficial risk profile for the patient . Methods . Adverse events associated with Bryan Disc arthroplasty and arthrodesis were compared in a prospect i ve r and omized study . Four hundred sixty-three ( 463 ) 
    Output:
    
We found low- quality evidence for no difference in effectiveness between various surgical techniques used for anterior discectomy .
There is a small , clinical ly irrelevant benefit on recovery and pain in favour of prosthetic disc surgery when compared with fusion techniques .