***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 . A prospect i ve r and omized controlled trial . Objectives . To examine the effectiveness of combined manipulative treatment , stabilizing exercises , and physician consultation compared with physician consultation alone for chronic low back pain . Summary of Background Data . Strong evidence exists that manual therapy provides more effective short-term pain relief than does placebo treatment in the management of chronic low back pain . The evidence for long-term effect is lacking . Methods . Two hundred four chronic low back pain patients , whose Oswestry disability index was at least 16 % , were r and omly assigned to either a manipulative-treatment group or a consultation group . All were clinical ly examined , informed about their back pain , provided with an educational booklet , and were given specific instructions based on the clinical evaluation . The treatment included four sessions of manipulation and stabilizing exercises aim ing to correct the lumbopelvic rhythm . Question naires inquired about pain intensity , self-rated disability , mental depression , health-related quality of life , health care costs , and production costs . Results . At the baseline , the groups were comparable , except for the percentage of employees ( P = 0.01 ) . At the 5- and 12-month follow-ups , the manipulative-treatment group showed more significant reductions in pain intensity ( P < 0.001 ) and in self-rated disability ( P = 0.002 ) than the consultation group . However , we detected no significant difference between the groups in health-related quality of life or in costs . Conclusions . The manipulative treatment with stabilizing exercises was more effective in reducing pain intensity and disability than the physician consultation alone . The present study showed that short , specific treatment programs with proper patient information may alter the course of chronic low back pain STUDY DESIGN A r and omized controlled comparative trial with an 8-month follow-up period was conducted . OBJECTIVE To compare the effect of the McKenzie treatment method with that of intensive dynamic strengthening training in patients with subacute or chronic low back pain . SUMMARY OF BACKGROUND DATA R and omized studies indicate that the efficacy of the McKenzie method in the treatment of patients with acute or subacute low back pain is debatable . Currently , no r and omized studies examining the effects of this method for patients with chronic low back pain have been published . METHODS For this study , 260 consecutive patients with low back pain and at least 8 weeks duration of symptoms ( 85 % of the patients had more than 3 months duration of symptoms ) were r and omized into two groups : Group A was treated with the McKenzie method ( n = 132 ) , and Group B was treated with intensive dynamic strengthening training ( n = 128 ) . The treatment period for both groups was 8 weeks at an outpatient clinic , followed by 2 months of self-training at home . Treatment results were recorded at the end of the treatment period at the clinic , then 2 and 8 months after . In both groups , 30 % of the patients were lost to follow-up evaluation . An intention-to-treat analysis of the main effect variables , disability , and pain was performed for all the patients included in the study . A supplementary analysis of the 180 patients who completed the full treatment program also was undertaken . RESULTS Intention-to-treat analysis showed a tendency toward a difference in reduction of disability in favor of the McKenzie group at the 2-month follow-up assessment ( P = 0.04 ) , but no differences at the end of treatment and at the 8-month follow-up evaluation . No differences in reduction of pain were observed at any time between the groups . The supplementary analysis of the patients who had completed the full intervention showed a tendency toward a difference in favor of the McKenzie method in reduction of pain at the end of treatment ( P = 0.02 ) . This difference reached statistical significance at the 2-month follow-up assessment ( P = 0.01 ) , but no difference was found after 8 months . The supplementary analysis showed no differences between the groups with regard to reduction of disability . CONCLUSION The McKenzie method and intensive dynamic strengthening training seem to be equally effective in the treatment of patients with subacute or chronic low back pain Study Design . A r and omized controlled trial with a 6-month follow-up period was conducted . Objective . To compare lumbar extension exercise and whole-body vibration exercise for chronic lower back pain . Summary of Background Data . Chronic lower back pain involves muscular as well as connective and neural systems . Different types of physiotherapy are applied for its treatment . Industrial vibration is regarded as a risk factor . Recently , vibration exercise has been developed as a new type of physiotherapy . It is thought to activate muscles via reflexes . Methods . In this study , 60 patients with chronic lower back pain devoid of “ specific ” spine diseases , who had a mean age of 51.7 years and a pain history of 13.1 years , practice d either isodynamic lumbar extension or vibration exercise for 3 months . Outcome measures were lumbar extension torque , pain sensation ( visual analog scale ) , and pain-related disability ( pain disability index ) . Results . A significant and comparable reduction in pain sensation and pain-related disability was observed in both groups . Lumbar extension torque increased significantly in the vibration exercise group ( 30.1 Nm/kg ) , but significantly more in the lumbar extension group ( + 59.2 Nm/kg ; SEM 10.2;P < 0.05 ) . No correlation was found between gain in lumbar torque and pain relief or pain-related disability ( P > 0.2 ) . Conclusions . The current data indicate that poor lumbar muscle force probably is not the exclusive cause of chronic lower back pain . Different types of exercise therapy tend to yield comparable results . Interestingly , well-controlled vibration may be the cure rather than the cause of lower back pain BACKGROUND AND PURPOSE The prescriptive validity of a treatment-oriented extension-mobilization category for patients with low back syndrome ( LBS ) was examined . SUBJECTS Of a total of 39 patients with LBS referred for physical therapy , 24 patients ( 14 male , 10 female ) , aged 14 to 50 years ( means = 31.3 , SD = 11.6 ) , were classified as having signs and symptoms indicating treatment with an extension-mobilization approach .  The remaining subjects were dismissed from the study . Patients in the extension-mobilization category were r and omly assigned to either an experimental ( treatment ) group ( n = 14 ) or a comparison group ( n = 10 ) . METHODS The experimental and comparison group subjects were treated with either mobilization and extension ( a treatment matched to the category ) or a flexion exercise regimen ( an unmatched treatment ) . Outcome was assessed with a modified Oswestry Low Back Pain Question naire administered initially and at 3 and 5 days after initiation of treatment . Data were analyzed with a 2 x 3 ( treatment group x treatment period ) analysis of variance . RESULTS The subjects ' rate of improvement , as indicated by the Oswestry question naire scores , was dependent on the treatment group to which they were assigned . Subjects treated with extension and mobilization positively responded at a faster rate than did those treated with a flexion-oriented program . CONCLUSION AND DISCUSSION This study illustrates that a priori classification of selected patients with LBS into a treatment category of extension and mobilization and subsequently treating the patients accordingly with specified interventions can be an effective approach to conservative management of selected patients Study Design . A r and omized , controlled trial . Objective . To examine the impact of physical function and pain on work status in patients who are long-term sick-listed because of back pain . Summary of Background Data . Sickness benefit is granted to a person who is incapable of working because of reduced functioning . Improved physical function and decrease of pain may be important in considering return to work . Methods . Physical performance ( five activities ) , disability , and pain ( self-reported question naires ) were assessed at baseline and at the 1-year follow-up evaluation in 117 patients r and omized to an intervention group ( n = 81 ) and a control group ( n = 36 ) . Results . At the 1-year follow-up evaluation , 50 % had returned to work . Statistically significant improvements were demonstrated from baseline to follow-up evaluation in returners to work : in the intervention group on all tests and in the control group on all except two performance tests . Improvement measures discriminated between returners and nonreturners to work in the intervention group on all physical tests and a pain test and in the control group on three physical tests and a pain test . In the intervention group , odds ratios for not having returned to work were high when test measures at follow-up indicated markedly impaired physical function and high pain ; in the control group , this appeared in high pain . Conclusions . Return to work was related to physical function and pain . More importance seemed to be attributed to physical performance in the intervention group than in the controls as a basis for returning patients to work Study Design A r and omized , placebo-controlled trial in which patients received either usual care by a general practitioner ( information and analgesics ) , or placebo physiotherapy given by a physiotherapist , or exercise therapy given by a physiotherapist . Objective To assess the efficacy of exercise therapy on sickness absence from work in patients with acute low back pain . Summary of Background Data Exercise therapy during the nonchronic phase of back pain is considered to reduce sickness absence , but this opinion is controversiel . Methods Patients with acute nonspecific low back pain and a paid job were included for analysis .  Sickness absence ( number of days ) was checked monthly during the 1-year follow-up period and compliance was also assessed . Results From 40 general practice s 363 patients who were gainfully employed were included . In the exercise therapy group the percentage of patients with sickness absence was higher and the duration of absence was longer than in the placebo and usual care groups , but these differences were not significant . Indications of more absence in the exercise therapy group appeared to be based largely on a greater number of patients with absences during the first 3 months . Patients in the exercise group who had not reported sick at entry had more sickness absences during the follow-up year than patients in the usual care and placebo group . Good compliance did not affect the results . Conclusions Exercise therapy for patients with acute low back pain does not reduce sickness absence BACKGROUND Chiropractic manipulation and strenuous exercise therapy have been shown effective in the treatment of nonspecific back pain .  Bone- setting , the predecessor of modern manual therapies , still survives in some parts of Finl and and was compared with a light exercise therapy and non-manipulative , pragmatic physiotherapy in a year-long r and omized controlled trial on patients with long-term back pain . METHODS One hundred fourteen ambulatory patients of working age with back pain for 7 weeks or more were r and omly assigned to the therapies , which were offered in up to 10 sessions during a 6-week treatment period . The outcome was measured by the Oswestry Disability Question naire . Sick-leaves and visits to health centers were recorded for 1 year before and after the therapy . RESULTS The Oswestry disability scores improved most in the bone- setting group ( P = .02 , Kruskall-Wallis test ) . Visits to health centers for back pain were reduced only in the physiotherapy group ( P = .01 , Wilcoxon test ) . Sick-leaves were not significantly different between groups . A secondary analysis based on the use of additional therapies after the intervention showed a possible subgroup with an enhanced effect from bone- setting . CONCLUSIONS Traditional bone- setting seemed more effective than exercise or physiotherapy on back pain and disability , even 1 year after therapy Design . R and omized prospect i ve study of the effects of three types of active therapy on back muscle function in chronic low back pain patients . Objectives . To quantify the effects of 3 months active therapy on strength , endurance , activation , and fatigability of the back entensor muscles . Summary of Background Data . Many studies have documented an association between chronic low back pain and diminished muscular performance capacity . Few studies have quantified the changes in these measures following interventions using objective measurement techniques or related them to changes in clinical outcome . Methods . A total of 148 individuals ( 57 % women ) with chronic low back pain ( age , 45.0 ± 10.0 years ; duration of low back pain , 10.9 ± 9.5 years ) were r and omized to a treatment that they attended for 3 months : active physiotherapy , muscle reconditioning on devices , or low-impact aerobics . Before and after therapy , assessment s were made of the following : trunk muscle strength ( in flexion , extension , lateral bending , and axial rotation ) , erector spinae activation ( maximal , and during forward bending movements ) , back extensor endurance ( Biering-S/orensen test ) , and erector spinae fatigability ( determined from changes in the median frequency of the surface electromyographic signal ) during isometric and dynamic tests . Results . A total of 132 of 148 patients ( 89 % ) completed the therapy . Isometric strength in each movement direction increased in all groups post-therapy ( P < 0.0008 ) , most notably in the devices group . Activation of the erector spinae during the extension tests also increased significantly in all groups and showed a weak , but significant , relationship with increased maximal strength ( P = 0.01 ) . Pretherapy 55 % of the subjects showed no relaxation of the back muscles at L5 when in the fully flexed position ; no changes were observed in any group post-therapy . Endurance time during the Biering-S/orensen test increased significantly post-therapy in all groups ( P = 0.0001 ) , but there were no significant changes in EMG-determined fatigability . Fatigability of the lumbar muscles at L5 ( EMG median frequency changes ) during the dynamic test increased post-therapy ( P = 0.0001 ) without group differences . Conclusion . Significant changes in muscle performance were observed in all three active therapy groups post-therapy , which appeared to be mainly due to changes in neural activation of the lumbar muscles and psychological changes concerning , for example , motivation or pain tolerance Abstract Objective : To evaluate effectiveness of 
    Output:
    
There is some evidence of effectiveness of grade d-activity exercise program in subacute low-back pain in occupational setting s , though the evidence for other types of exercise therapy in other population s is inconsistent .
Exercise therapy appears to be slightly effective at decreasing pain and improving function in adults with chronic low-back pain , particularly in healthcare population s. In subacute low-back pain there is some evidence that a grade d activity program improves absenteeism outcomes , though evidence for other types of exercise is unclear .
In acute low-back pain , exercise therapy is as effective as either no treatment or other conservative treatments