***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 , r and omized , controlled . Level 1 evidence . Objective To report functional outcomes at 48 months follow-up on prospect ively r and omized patients to either the Bryan cervical disc prosthesis or anterior cervical discectomy and fusion ( ACDF ) at a single site . Summary of Background Data Surgical treatment of cervical disc pathology can involve discectomy and fusion ( ACDF ) , the gold st and ard technique . The safety and effectiveness of this procedure has been established and demonstrated in the literature , however , limitations have evolved and alternatives such as disc replacement are being investigated . Intervertebral disc replacement is design ed to preserve motion , both at affected and adjacent levels avoiding limitations of fusion such as adjacent level degeneration . New onset degenerative changes and possible recurring neurologic symptoms may be deferred or eliminated with cervical disc replacement . A recent multicenter trial with 24 months follow-up has shown the Bryan disc to compare favorably with ACDF . Continued follow-up is needed to further evaluate and compare functional outcomes in both these cohorts . Methods A total of 47 patients were enrolled at our site as part of an ongoing multicenter prospect ively r and omized study investigating ACDF versus Bryan cervical disc prosthesis . Functional outcomes are now reported at 48 months follow-up for our cohort of participants . Neck disability index score ( NDI ) , VAS neck and arm and SF-36 both physical and mental as well as complications and reoperations will be reported . Results Functional outcome data collected at routine follow-up for 48-months has favorably demonstrated improved functional outcomes for NDI , neck/arm pain VAS scores , and the SF-36 physical/mental health component scores for the Bryan arthroplasty and ACDF cohorts . The NDI scores for the Bryan arthroplasty preoperatively was 51 and at 48 months 10 . For ACDF preoperative NDI score was also 51 and at 48 months 16.7 . At 48 months NDI success , measured by ≥15 points NDI improvement demonstrated a 93.3 % success for Bryan arthroplasty and an 82.4 % success for ACDF . VAS neck pain scores for the Bryan arthroplasty preoperatively was 76.2 and at 48 months was 13.6 . VAS neck pain scores for ACDF preoperatively was 80.6 and at 48 months was 28.1 . Arm Pain scores were also measured and for the Bryan arthroplasty preoperatively measured 78.8 and at 48 months 10.8 . For ACDF arm pain scores preoperatively measured 77.1 and at 48 months 21.7 . These outcomes have not been associated with any degradation of outcome measures from 2 to 4 years . During the 48 months of follow-up at our institution we also report 6 secondary surgeries in our control group ( ACDF ) and only 1 in our investigational group ( Bryan ) . Of the 6 surgeries in the control group performed , 3 or 12 % to date were for adjacent level degenerative disease and 1 or 4 % for remote level degenerative disc disease . The remaining 2 surgeries were performed on the same patient for a pseudarthrosis . In the investigational group there was only 1 secondary surgery performed to date for adjacent level disease 5 % . Conclusions At 48 months , cervical arthroplasty with the Bryan cervical disc prosthesis continues to compare favorably to ACDF at our institution . There has been no degradation of functional outcomes from 24 to 48 months for NDI , VAS of neck and arm , and SF-36 . There has been a lower incidence of secondary surgeries for the Bryan arthroplasty cohort to date OBJECT Spinal arthroplasty is becoming more widely performed in the treatment of degenerative cervical disc disease . Although this new technology may offer benefits over arthrodesis , it also requires that the surgeon acquire new operative techniques , and new potential complications are introduced . To determine the incidence and distribution of perioperative complications , the authors analyzed their early data obtained in a series of patients treated with the Bryan Cervical Disc prosthesis .  METHODS The authors prospect ively recorded operative data , complications , and clinical and radiographic outcome data in all patients treated with Bryan prosthesis-based arthroplasty at two tertiary care centers since 2001 . Patients underwent st and ard anterior cervical discectomy followed by one- to three-level arthroplasty . Ninety-six discs were implanted in 74 patients . The perioperative complication rate was 6.2 % per treated level . In one patient a retropharyngeal hematoma developed , requiring evacuation . Neurological worsening occurred in three patients . Intraoperative migration of the prosthesis was observed in one two-level case , whereas delayed migration occurred in one patient with postoperative segmental kyphosis . In another patient with severe postoperative segmental kyphosis , revision was required with a customized lordotic prosthesis . Heterotopic ossification and spontaneous fusion occurred in two cases ; motion was preserved in the remaining 94 prostheses . Partial dislocation of the prosthesis in extension occurred in one patient with preoperative segmental hypermobility , the first reported failure of a Bryan prosthesis . Twenty-five percent of patients reported neck and shoulder pain during the late follow-up period . There was a trend toward increased kyphosis of the C2 - 7 curvature postoperatively . CONCLUSIONS The Bryan prosthesis was effective in maintaining spinal motion . Major perioperative and device-related complications were infrequent 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 ) patients having cervical radiculopathy and or myelopathy at a single level were treated at 31 sites . A total of 242 patients received the disc and 221 patients had anterior cervical discectomy and fusion .  All patients were evaluated before surgery and at 1.5 , 3 , 6 , 12 , and 24 months after surgery . Adverse events were recorded concurrently and categorized by severity and as medically or surgically related . Results . No differences in overall medical events occurred between groups . Surgically related events occurred more frequently in the investigational group secondary to more complaints of postoperative dysphagia and late medical events occurred more frequently in the investigational patients . However , the more severe World Health Organization Grade 3 and 4 events occurred more frequently in the arthrodesis patients related to treatment of pseudarthrosis and persistent symptoms . Significantly , more cervical spine reoperations occurred in the fusion group . Only one spinal cord injury occurred and it was in the arthrodesis group and no patients had deep infection or death related to either procedure . Conclusion . Bryan cervical disc replacement and anterior cervical fusion are both safe procedures with a low incidence of significant adverse events related to the procedure . Statistically , more serious adverse events and reoperations occurred in the fusion group while a greater number of less serious surgically related events were seen in the investigational group BACKGROUND CONTEXT The Neck Disability Index ( NDI ) , the short form-36 ( SF-36 ) physical component summary ( PCS ) , and pain scales for arm and neck pain are increasingly used to evaluate treatment effectiveness after cervical spine surgery . The minimum clinical ly important difference ( MCID ) is a threshold of improvement that is clinical ly relevant to the patient . However , the true goal is to provide the patient with a substantial clinical benefit ( SCB ) . PURPOSE This study determines the MCID and SCB using common anchor-based methods for NDI , PCS , and pain scales for arm and neck pain in patients undergoing cervical spine fusion for degenerative disorders . STUDY DESIGN / SETTING The study setting is a longitudinal cohort in a multisurgeon spine specialty clinic . PATIENT SAMPLE The sample comprises 505 patients who underwent a cervical fusion for degenerative spine conditions and who have prospect ively collected outcome scores with a minimum 1-year follow-up . OUTCOME MEASURES The outcome measures of the study were NDI , SF-36 , and numeric rating scales for arm and neck pain . METHODS The MCID and SCB values for NDI , PCS , and pain scales for arm and neck pain were determined using receiver operating characteristic ( ROC ) curve analysis with the Health Transition Item of the SF-36 as an anchor . The Health Transition Item asks a patient " Compared to one year ago , how would you rate your health in general now ? " with answers ranging from " Much Better , " " Somewhat Better , " " About the Same , " " Somewhat Worse , " to " Much Worse . " An ROC curve was constructed for each measure . The ROC curve-derived MCID was the change score with equal sensitivity and specificity to distinguish the " Somewhat Better " from the " About the Same " patients . The ROC curve-derived SCB was the change score with equal sensitivity and specificity to distinguish the " Much Better " from the " Somewhat Better " patients . Distribution-based methods including the st and ard error of the mean and the minimum detectable change were also used to calculate MCID . RESULTS The calculated MCID is 7.5 for the NDI , 4.1 for SF-36 PCS , and 2.5 for arm and neck pain . The calculated SCB is 9.5 for the NDI , 6.5 for SF-36 PCS , and 3.5 for arm and neck pain . CONCLUSIONS Patients with an eight-point decrease in NDI , a 4.1-point increase in PCS , and a three-point decrease in arm or neck pain can detect a minimally clinical ly important change . Patients with a 10-point decrease in NDI , a 6.5-point increase in PCS , and a four-point decrease in arm or neck pain can detect an SCB after cervical spine fusion Study Design . Prospect i ve , r and omized , controlled study of patients with lumbar disc herniations , operated either in a full-endoscopic or microsurgical technique .  Objective . Comparison of results of lumbar discectomies in full-endoscopic interlaminar and transforaminal technique with the conventional microsurgical technique . Summary of Background Data . Even with good results , conventional disc operations may result in subsequent damage due to trauma . Endoscopic techniques have become the st and ard in many areas because of the advantages they offer intraoperatively and after surgery . With the transforaminal and interlaminar techniques , 2 full-endoscopic procedures are available for lumbar disc operations . Methods . One hundred seventy-eight patients with full-endoscopic or microsurgical discectomy  underwent follow-up for 2 years . In addition to general and specific parameters , the following measuring instruments were used : VAS , German version North American Spine Society Instrument , Oswestry Low-Back Pain Disability Question naire . Results . After surgery 82 % of the patients no longer had leg pain , and 14 % had occasional pain . The clinical results were the same in both groups . The recurrence rate was 6.2 % with no difference between the groups . The full-endoscopic techniques brought significant advantages in the following areas : back pain , rehabilitation , complications , and traumatization . Conclusion . The clinical results of the full-endoscopic technique are equal to those of the microsurgical technique . At the same time , there are advantages in the operation technique and reduced traumatization . With the surgical devices and the possibility of selecting an interlaminar or posterolateral to lateral transforaminal procedure , lumbar disc herniations outside and insidethe spinal canal can be sufficiently removed using the full-endoscopic technique , when taking the appropriate criteria into account . Full-endoscopic surgery is a sufficient and safe supplementation and alternative to microsurgical procedures BACKGROUND Although there have been case reports describing the use of cervical disc arthroplasty for the treatment of myelopathy , there is a concern that motion preservation may maintain microtrauma to the spinal cord , negatively affecting the clinical results . As we are not aware of any studies on the use of arthroplasty in this scenario , we performed a cross-sectional analysis of two large , prospect i ve , r and omized multicenter trials to evaluate the efficacy of cervical disc arthroplasty for the treatment of myelopathy . METHODS The patients in the current study were a cohort of patients who were enrolled in the United States Food and Drug Administration Investigational Device Exemption studies of the Prestige ST and Bryan disc replacements ( Medtronic , Memphis , Tennessee ) . The inclusion criteria were myelopathy and spondylosis or disc herniation at a single level from C3 to C7 . Clinical outcome measures were collected preoperatively and at six weeks , three months , six months , twelve months , and twenty-four months postoperatively . RESULTS A total of 199 patients were included in the present study ; 106 patients ( 53 % ) underwent arthroplasty , whereas ninety-three ( 47 % ) underwent arthrodesis . The Neck Disability Index , Short Form-36 scores , and specific arm and neck pain scores improved significantly from baseline at all time points . Patients in all four groups had improvement in the postoperative neurological status and gait function ; at twenty-four months after surgery , 90 % ( 95 % confidence interval , 77.8 % to 96.6 % 
    Output:
    
Patients with PTUCD arthroplasty had also less radiological degenerative changes at the upper adjacent level .
Overall adverse events were twice more frequent in patients with ACDF .
The rate of revision surgery including both adjacent and index level was slightly higher in patients with ACDF , showing no statistically significant difference .
Conclusions According to this review , PTUCD arthroplasty showed a global superiority to ACDF in clinical outcomes .
The impact of both surgical techniques on the cervical spine ( radiological spine deterioration and /or complications ) was more severe in patients undergoing ACDF .
However , the rate of revision surgeries at any cervical level was equivalent for ACDF and PTUCD arthroplasty