***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: Objectives : Pathophysiological mechanisms underlying spinal cord injury ( SCI ) partially involve edema and formation of a hematoma . Myelotomy seems to be a promising intervention . However , the appropriate timing of myelotomy is still unknown in SCI . Here we aim ed to determine the timing of microsurgical myelotomy in an animal model of SCI . Methods : The SCI model was contusion-induced with a new york university impactor . Sixty-five adult female rats were r and omly divided into the following groups : laminectomy alone ( the ‘ sham group ’ , SG ) , laminectomy plus contusion ( the ‘ contusion group ’ , CG ) or laminectomy plus contusion followed by myelotomy at 8 , 24 or 48 h ( 8 h-MTG [ myelotomy-treated group ] , 24 h-MTG or 48 h-MTG ) . Functional recovery was evaluated via the open field test and the inclined plane test every week after SCI . The percentage of spared white matter area ( SWMA ) and ultrastructure characteristics of the injured dorsolateral spinal cord were determined on the 42nd day after SCI . Results : Compared with the CG , myelotomy at 8 h-MTG or 24 h-MTG greatly improved the BASSO-BEATTIE- BRESNAHAN scores ( P<0.008 ) , whereas the 48 h-MTG showed less efficacy ( P=0.023 ) . All myelotomy groups showed higher mean angle values in an inclined plane test ( P<0.005 ) and had greater percentages of SWMA than the CG . Rats in the 24 h-MTG showed a higher intra-axonal fraction and myelin fraction than those in 48 h-MTG ( P<0.005 ) . Conclusion : Myelotomy up to 48 h after SCI improves recovery in rats . The potential time window of myelotomy may be between 8 and 24 h after SCI Background There is convincing pre clinical evidence that early decompression in the setting of spinal cord injury ( SCI ) improves neurologic outcomes . However , the effect of early surgical decompression in patients with acute SCI remains uncertain . Our objective was to evaluate the relative effectiveness of early ( < 24 hours after injury ) versus late ( ≥24 hours after injury ) decompressive surgery after traumatic cervical SCI . Methods We performed a multicenter , international , prospect i ve cohort study ( Surgical Timing in Acute Spinal Cord Injury Study : STASCIS ) in adults aged 16–80 with cervical SCI . Enrolment occurred between 2002 and 2009 at 6 North American centers . The primary outcome was ordinal change in ASIA Impairment Scale ( AIS ) grade at 6 months follow-up . Secondary outcomes included assessment s of complications rates and mortality . Findings A total of 313 patients with acute cervical SCI were enrolled . Of these , 182 underwent early surgery , at a mean of 14.2(±5.4 ) hours , with the remaining 131 having late surgery , at a mean of 48.3(±29.3 ) hours . Of the 222 patients with follow-up available at 6 months post injury , 19.8 % of patients undergoing early surgery showed a ≥2 grade improvement in AIS compared to 8.8 % in the late decompression group ( OR = 2.57 , 95 % CI:1.11,5.97 ) . In the multivariate analysis , adjusted for preoperative neurological status and steroid administration , the odds of at least a 2 grade AIS improvement were 2.8 times higher amongst those who underwent early surgery as compared to those who underwent late surgery ( OR = 2.83 , 95 % CI:1.10,7.28 ) . During the 30 day post injury period , there was 1 mortality in both of the surgical groups . Complications occurred in 24.2 % of early surgery patients and 30.5 % of late surgery patients ( p = 0.21 ) . Conclusion Decompression prior to 24 hours after SCI can be performed safely and is associated with improved neurologic outcome , defined as at least a 2 grade AIS improvement at 6 months follow-up Using data from the Second National Acute Spinal Cord Injury Study ( NASCIS II ) , the authors sought to characterize the role of surgery in the management of traumatic spinal cord injury and to examine the interaction between pharmacological treatment and surgery .  Patients who did not undergo surgery  had more severe spinal cord injuries initially than those who had surgery .  However , no differences in neurological improvement at 1-year follow-up were found between those who underwent surgery and those who did not . The results suggest that either early surgery ( < or = 25 hours after injury ) or late surgery ( > 200 hours ) may be associated with increased neurological recovery , particularly motor function , but these results are equivocal . Surgery was not shown to interact with pharmacological treatments , indicating that the effect of drug treatment in NASCIS II , reported elsewhere , is not influenced by surgery . Other independent variables that best predicted improvement in motor score were age of 25 years or younger , incomplete injury , and lower baseline emergency department neurological scores . This study does not provide clinical ly relevant evidence concerning the efficacy of timing or the value of surgery in treating patients with spinal cord injuries . A r and omized study on the timing and efficacy of spinal cord surgery is needed to obtain valid comparisons of the efficacy of surgical treatments BACKGROUND CONTEXT Surgical treatment in the setting of central cord syndrome ( CCS ) has become safer since Schneider 's original description . It is generally accepted that a decompressive surgical intervention is a valid treatment option in a patient with CCS and radiographic evidence of spinal cord compression . The optimal timing of surgical intervention for CCS remains controversial . PURPOSE To review a single institution 's experience managing CCS , with particular emphasis on surgical versus medical management , timing of surgery , neurologic outcomes , hospital length of stay , and complications . STUDY DESIGN Retrospective review . PATIENT SAMPLE One hundred twenty-six patients diagnosed with CCS were treated at Wake Forest University Baptist Medical Center between June 1985 and September 2006 . OUTCOME MEASURES Neurological outcomes were measured using the Frankel grading scale . Other outcome measures included hospital and intensive care unit ( ICU ) length of stay and complication profiles . METHODS A retrospective chart review was performed on patients admitted to Wake Forest University Baptist Medical Center with the diagnosis of traumatic central cord injury from June 1985 to September 2006 with institutional review board approval . Neurologic status was recorded on presentation and at maximum follow-up using the Frankel classification . The surgical cohort was stratified into three subgroups with regard to the timing of surgical intervention after injury : surgery less than 24 hours after injury , surgery greater than 24 hours after injury but during the initial admission , and delayed operative intervention on a second hospital admission . Other variables collected included ICU and hospital length of stay and complication profiles . Data analyses were performed using SPSS ( SPSS , Chicago , IL , USA ) and Excel 2002 ( Microsoft , Seattle , WA , USA ) . RESULTS A total of 126 patients treated for CCS were review ed . Sixty-seven patients received surgery compared with 59 patients managed nonoperatively . Of those managed operatively , 16 patients received surgery within 24 hours of the time of injury . There were 34 patients who received surgery greater than 24 hours after the time of injury but during their initial admission with a mean time to surgery of 6.4 days ( 5 - 52 days ) . There were 17 patients who received their operation on a second hospital admission with a mean time interval of 137 days between injury and surgery ( 3 - 209 ) . Mean follow-up was 32 months ( 1 - 210 months ) . An improvement in Frankel grade was seen in the overall operative cohort compared with those patients who received medical management alone . No statistically significant difference in neurologic outcome using Frankel grade s was identified between the surgical subgroups with regard to timing of surgery . A trend toward decreased length of stay was seen in the surgical subgroup that received surgery during their initial admission . No statistically significant difference was identified between complication rates for the operative and nonoperative groups ; however , a trend toward fewer complications and deaths was seen in those who received surgery in the first 24 hours or during the initial hospitalization . CONCLUSIONS Surgical treatment in the setting of CCS has become safer since Schneider 's original description . Acknowledging its numerous limitations , this retrospective study supports surgical intervention in the setting of CCS as a safe effective management option . Improved Frankel grade s were identified in those patients managed surgically compared with those receiving medical management alone . The data further shed light on the safety and potential benefits of early operative intervention for acute CCS compared with delayed surgical treatment . A prospect i ve r and omized controlled trial is needed to definitively compare surgical versus medical management and /or early versus delayed surgical treatment in the setting of traumatic CCS Study Design Prospect i ve observational study . Purpose To assess the clinical outcome after early versus late decompression for traumatic cervical cord injury . Overview of Literature Traumatic spinal cord injury is common globally with the most tragic outcomes in the cervical spine . Although recent studies have shown that early decompression results in more favourable outcome , its authority is yet to be established . Methods Study on 98 patients with a traumatic cervical cord injury was conducted over a period of 5 years . The patients who were operated on within 24 hours of the onset of the primary injury ( n=34 ) were classified as the early group , and those who were  operated on after 24 hours of the onset of the injury ( n=64 ) were categorized as the late group . The outcome of both the groups was assessed using the American Spinal Injury Association ( ASIA ) Impairment Scale ( AIS ) at the 6-month follow-up . Results The patients in the early group were operated on at a mean time of 18.4 hours ( range , 13 - 24 hours ) while patients were operated on at a mean time of 52.7 hours ( range , 31 - 124 hours ) in the late group . At the 6-month follow-up , 7 ( 23.3 % ) in the early group and 5 ( 8.7 % ) in the late group showed > 2 grade improvement in the AIS . Conclusions The results of patients undergoing decompression within 24 hours of the injury are better than those who are operated on later . An attempt should be made to decompress the traumatic cervical spine early in all possible cases STUDY DESIGN A prospect i ve , longitudinal study of multiply injured patients treated with segmental instrumentation for spinal fractures with a minimum 2-year follow-up . OBJECTIVES To determine whether urgent stabilization of  spinal fractures in severely injured patients increases the risk of surgery compared with early treatment and historical results . SUMMARY AND BACKGROUND DATA Opinion in clinical studies is divided about whether operative treatment offers an advantage over nonoperative treatment in isolated spine fractures . Concomitant trauma is rarely discussed relative to decision making or surgical timing . Urgent stabilization of long-bone fractures improves survival and outcome in polytrauma patients . To date , urgent treatment of spine fractures in polytrauma patients has not been considered in the literature . METHODS Seventy-five consecutive patients treated with segmental instrumentation for spinal trauma  were observed prospect ively to assess perioperative and longterm outcome . Twenty-seven patients with severe polytrauma ( injury severity score , > 26 ) were separately analyzed . Perioperative and postoperative results were analyzed relative to timing of surgery , injury severity score , and surgical approach . Urgent treatment was defined as that provided within 24 hours of the spinal injury , and early treatment was defined as that provided between 24 and 72 hours after injury . RESULTS Twenty-five patients ( 93 % ) sustained two or more major injuries in addition to the spine fracture , and 17 of 27 ( 63 % ) had neurologic injury . The mean injury severity score approached or exceeded the LD50 ( 50 % expected mortality ) in each group--36.0 for the early-treatment group and 42.0 for the urgent group -- but only one patient in each group died . There were no deep venous thromboses , pulmonary emboli , neurologic injuries , decubiti , deep wound infections , or episodes of sepsis in either group . Blood loss for anterior procedures was significantly higher in the urgent group , but estimated blood loss for posterior procedures was similar for both groups . At 49 months ' mean follow-up , no revisions were necessitated by the urgent spinal treatment . CONCLUSIONS Urgent spinal stabilization is safe and appropriate in polytrauma patients when progressive neurologic deficit , thoracoabdominal trauma , or fracture instability increase the risks of delayed treatment Study Design . A prospect i ve analysis evaluating neurologic outcome after early versus late surgery for cervical spinal cord trauma . Objectives . The study was conducted to determine whether neurologic and functional outcome is improved in traumatic cervical spinal cord‐injured patients ( C3‐T1 , American Spinal Injury Association grade s A‐D ) who had early surgery ( < 72 hours after spinal cord injury ) compared with those patients who had late surgery ( > 5 days after spinal cord injury ) . Summary of Background Data . There is considerable controversy as to the appropriate timing of surgical decompression and stabilization for cervical spinal cord trauma . There have been numerous retrospective studies , but no prospect i ve studies , to determine whether neurologic outcome is best after early versus late surgical treatment for cervical spinal cord injury . Methods . Patients meeting appropriate inclusion criteria were r and omized to an early ( < 72 hours after spinal cord injury ) or late ( > 5 days after spinal cord injury ) surgical treatment protocol .  The neuro 
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There was significant variability in the definition of early and late decompression in both clinical and pre clinical studies .
Pre clinical data were in favor of early decompression .
From a clinical st and point , there was only level II evidence proving safety and feasibility of early decompression with no definite evidence of improved outcome for any of the two groups .
There is growing evidence in favor of early decompression following SCI .
Early decompression was proven to be clinical ly safe and feasible , but there is still no definite proof that early decompression leads to improved outcomes .