***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 : To test the effects of pregabalin on the induction of neurogenic claudication . Methods : This study was a r and omized , double-blind , active placebo-controlled , 2-period , crossover trial . Twenty-nine subjects were r and omized to receive pregabalin followed by active placebo ( i.e. , diphenhydramine ) or active placebo followed by pregabalin . Each treatment period lasted 10 days , including a 2-step titration . Periods were separated by a 10-day washout period , including a 3-day taper phase after the first period . The primary outcome variable was the time to first moderate pain symptom ( Numeric Rating Scale score ≥4 ) during a 15-minute treadmill test ( Tfirst ) . Secondary outcome measures included pain intensity at rest , pain intensity at the end of the treadmill test , distance walked , and vali date d self-report measures of pain and functional limitation including the Rol and -Morris Disability Question naire , modified Brief Pain Inventory – Short Form , Oswestry Disability Index , and Swiss Spinal Stenosis Question naire . Results : No significant difference was found between pregabalin and active placebo for the time to first moderate pain symptom ( difference in median Tfirst = −1.08 [ 95 % confidence interval −2.25 to 0.08 ] , p = 0.61 ) . In addition , none of the secondary outcome measures of pain or functional limitation were significantly improved by pregabalin compared with active placebo . Conclusions : Pregabalin was not more effective than active placebo in reducing painful symptoms or functional limitations in patients with neurogenic claudication associated with lumbar spinal stenosis . Classification of evidence : This study provides Class I evidence that for patients with neurogenic claudication , compared with diphenhydramine , pregabalin does not increase the time to moderate pain during a treadmill test Study Design . A prospect i ve , r and omized , single ( investigator ) blind , comparative efficacy trial was conducted . Objective . To compare the efficacy of continuous low-level heat wrap therapy ( 40 C , 8 hours/day ) with that of ibuprofen ( 1200 mg/day ) and acetaminophen ( 4000 mg/day ) in subjects with acute nonspecific low back pain . Summary of Background Data . The efficacy of topical heat methods , as compared with oral analgesic treatment of low back pain , has not been established . Methods . Subjects ( n = 371 ) were r and omly assigned to heat wrap ( n = 113 ) , acetaminophen ( n = 113 ) , or ibuprofen ( n = 106 ) for efficacy evaluation , or to oral placebo ( n = 20 ) or unheated back wrap ( n = 19 ) for blinding . Outcome measures included pain relief , muscle stiffness , lateral trunk flexibility , and disability . Efficacy was measured over two treatment days and two follow-up days . Results . Day 1 pain relief for the heat wrap ( mean , 2 ) was higher than for ibuprofen ( mean , 1.51;P = 0.0007 ) or acetaminophen ( mean , 1.32;P = 0.0001 ) . Extended mean pain relief ( Days 3 to 4 ) for the heat wrap ( mean , 2.61 ) also was higher than for ibuprofen ( mean , 1.68;P = 0.0001 ) or acetaminophen ( mean , 1.95;P = 0.0009 ) . Lateral trunk flexibility was improved with the heat wrap ( mean change , 4.28 cm ) during treatment ( P ≤ 0.009 vs acetaminophen [ mean change , 2.93 cm ] , P ≤ 0.001 vs ibuprofen [ mean change , 2.51 cm ] ) . The results were similar on Day 4 . Day 1 reduction in muscle stiffness with the heat wrap ( mean , 16.3 ) was greater than with acetaminophen ( mean , 10.5;P = 0.001 ) . Disability was reduced with the heat wrap ( mean , 4.9 ) , as compared with ibuprofen ( mean , 2.7;P = 0.01 ) and acetaminophen ( mean , 2.9;P = 0.0007 ) , on Day 4 . None of the adverse events were serious . The highest rate ( 10.4 % ) was reported in the ibuprofen group . Conclusion . Continuous low-level heat wrap therapy was superior to both acetaminophen and ibuprofen for treating low back pain A double-blind , 18-center , balanced trial of diflunisal vs. cyclobenzaprine HCl vs. these two drugs combined vs. placebo produced complete results from 175 patients . They had sought treatment at the cooperating centers for acute painful spasms of the back within a day or two of trauma or strain . Global results over the 7 to 10 days of observations revealed a clinical ly and statistically significant superiority of the combined therapy by Day 4 ( P=0.006 ) and almost all patients recovered within a week to 10 days . A combination therapy with an effective safe analgesic and a true muscle relaxant for less than a week appears to be an excellent relief measure for acute back problems Tizanidine and aceclofenac individually have shown efficacy in the treatment of low back pain . The efficacy and tolerability of the combination have not yet been established . The objective of the study was to evaluate the efficacy and safety of aceclofenac-tizanidine fixed dose combination against aceclofenac alone in patients with acute low back pain . This double-blind , double-dummy , r and omized , comparative , multicentric , parallel group study enrolled 197 patients of either sex in the age range of 18–70 years with acute low back pain . The patients were r and omized to receive either aceclofenac ( 100 mg)–tizanidine ( 2 mg ) b.i.d or aceclofenac ( 100 mg ) alone b.i.d for 7 days . The primary efficacy outcomes were pain intensity ( on movement , at rest and at night ; on VAS scale ) and pain relief ( on a 5-point verbal rating scale ) . The secondary efficacy outcomes measures included functional impairment ( modified Schober ’s test and lateral body bending test ) and patient ’s and investigator ’s global efficacy assessment .  aceclofenac – tizanidine was significantly superior to aceclofenac  for pain intensity ( on movement , at rest and at night ; P < 0.05 ) and pain relief ( P = 0.00 ) on days 3 and 7 . There was significant increase in spinal flexion in both the groups from baseline on days 3 and 7 with significant difference in favour of the combination group ( P < 0.05 ) . There were significantly more number of patients with excellent to good response for the aceclofenac – tizanidine treatment as compared to aceclofenac alone ( P = 0.00 ) . Both the treatments were well tolerated . In this study , aceclofenac – tizanidine combination was more effective than aceclofenac alone and had a favourable safety profile in the treatment of acute low back pain This large , open-label , r and omized , parallel-group , multicenter study compared two oral sustained-release opioids (SROs)--AVINZA ( A-MQD ) , morphine sulfate extended-release capsules given once a day , and OxyContin ( O-ER ) , oxycodone modified-release tablets given twice a day -- in SRO-naive subjects ages 30 to 70 with chronic , moderate to severe low back pain . Of the 392 subjects enrolled and r and omized , 266 ( 132 in the A-MQD group and 134 in the O-ER group ) completed the  opioid dose titration phase and entered an eight-week evaluation phase . During the evaluation phase , A-MQD achieved significantly better pain control than O-ER , as demonstrated by a greater decrease from baseline in pain scores obtained four times daily during weeks one , four , and eight ( p = 0.002 ) . The number of breakthrough-pain rescue medication doses adjusted for the number of patient days was significantly lower in the A-MQD group ( p < 0.0001 ) . Better pain control with A-MQD was achieved with a significantly lower daily opioid dose than with O-ER ( mean 69.9 mg and 91 mg morphine equivalents , respectively ; p = 0.0125 ) . Quality of sleep was significantly better with A-MQD for the entire evaluation phase ( p = 0.0026 ) . The incidence and severity of elicited opioid side effects were similar in the two groups . This trial demonstrated that once-daily A-MQD provides consistent around-the-clock pain relief in patients with low back pain . In patients who completed opioid dose titration , A-MQD was significantly better than O-ER for reducing pain and improving sleep , while requiring a lower daily opioid dose & NA ; We evaluated the efficacy of pregabalin in patients with chronic lumbosacral radiculopathy . This r and omized , controlled , withdrawal trial included five phases : screening ( 4–18 days ) ; run‐in ( 4–10 days ) to screen out placebo responders ; single‐blind ( 28 days ) to identify pregabalin responders ; double‐blind to r and omize responders to pregabalin or placebo ( 35 days ) ; and final study medication taper ( 7 days ) . The primary endpoint was time to loss of response ( LOR ) during the double‐blind phase ( ≥1‐point increase in pain , discontinuation , or rescue‐medication use ) . In the single‐blind phase , 58 % of patients had ≥30 % pain reduction . In the double‐blind phase , pregabalin ( n = 110 ) and placebo ( n = 107 ) groups did not differ significantly in time to LOR . Adverse events caused the discontinuation of 9.9 % and 5.6 % of pregabalin‐treated and placebo‐treated patients , respectively . Most patients with chronic lumbosacral radiculopathy  responded to pregabalin therapy ; however , time to LOR did not significantly differ between pregabalin and placebo . Considering the results of all phases of the study , it is difficult to draw definitive conclusions from it , suggesting a need for further work to underst and the clinical potential of pregabalin treatment for lumbosacral radiculopathy Background Corticoids have potent anti-inflammatory effects , which may help in relieving pain and dysfunction associated with lumbar canal stenosis . We assessed the effectiveness of a decreasing-dose regimen of oral corticoids in the treatment of lumbar canal stenosis in a prospect i ve , double-blind , r and omized , placebo-controlled trial . Results Sixty-one patients with lumbar canal stenosis ( 50–75 years ; canal area < 100 mm2 at L3/L4 , L4/L5 , and /or L5/S1on magnetic resonance imaging ; and claudication within 100 m were electronically r and omized to an oral corticoid group ( n = 31 ) or a placebo group ( n = 30 ) . The treatment group received 1 mg/kg of oral corticoids daily , with a dose reduction of one-third per week for 3 weeks . Patients and controls were assessed by the Short Form 36 Health Survey , Rol and –Morris Question naire , 6-min walk test , visual analog scale , and a Likert scale . All instruments showed similar outcomes for the corticoid and placebo groups ( P > 0.05 ) . Obese patients exhibited more severe symptoms compared with non-obese patients . L4/L5 stenosis was associated with more severe symptoms compared with stenosis at other levels . Conclusion The oral corticoid regimen used in this study was not effective in the treatment of lumbar canal stenosis Study Design . Two replicate , 4-week , r and omized , double-blind , placebo-controlled , trials of rofecoxib 25 and 50 mg versus placebo for chronic low back pain . Objectives . To determine the efficacy and safety of two doses of rofecoxib compared to placebo in the treatment of chronic low back pain . Summary of Background Data . Although nonsteroidal anti-inflammatory drugs are commonly prescribed for chronic low back pain , their efficacy is unproven and toxicity can be serious . These studies evaluated the efficacy and tolerability of rofecoxib , a selective COX-2 inhibitor , in the treatment of chronic low back pain . Methods . Patients with chronic low back pain were r and omized 1:1:1 to rofecoxib 25 mg , 50 mg , or placebo once daily . Primary endpoint : Low Back Pain Intensity . Secondary endpoints : Pain Bothersomeness , Global Assessment s of Response to Therapy , Global Assessment of Disease Status , Rol and -Morris Disability Question naire , SF-12 Health Survey , Use of Rescue Acetaminophen , and Discontinuations Due to Lack of Efficacy . Results . Combining both studies , 690 patients were r and omized to placebo ( N = 228 ) ,  rofecoxib 25 mg ( N = 233 ) , or  rofecoxib 50 mg ( N = 229 ) . Mean ( ± SD ) age was 53.4 ( ± 12.9 ) years , pain duration 12.1 ( ± 11.8 ) years , 62.3 % female .  Both rofecoxib groups improved significantly . Mean differences from placebo in pain intensity were −13.50 mm , −13.81 mm ( 25 , 50 mg doses ) respectively ( P < 0.001 ) . Both regimens were superior to placebo 
    Output:
    
Three trials in this review found no differences between an NSAID and