***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 
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    Input: Background : Pain following spinal cord injury ( SCI ) is a therapeutic challenge . Only a few treatments have been assessed in r and omized , controlled trials . The primary objective of the present study was to examine the analgesic effect of ketamine and lidocaine in a group of patients with neuropathic pain below the level of spinal cord injury . We also wanted to assess sensory abnormalities to see if this could help us to identify responders and if treatments result ed in changes of sensibility OBJECTIVES Complex regional pain syndrome ( CRPS ) , formerly known as reflex sympathetic dystrophy ( RSD ) , is a painful , disabling disorder for which treatment is difficult . The aim of this study was to determine the efficacy of pamidronate in a double-blind r and omized placebo-controlled trial . METHODS Patients referred to our regional multidisciplinary pain management center who fulfilled the International Association for the Study of Pain criteria for CRPS Type I were enrolled in the study over a 2-year period . Patients were administered , intravenously , either pamidronate , 60 mg as a single dose , or normal saline . Patients ' pain scores , global assessment of disease severity scores , and functional assessment ( SF-36 ) scores were documented at baseline and at 1 and 3 months . RESULTS Twenty-seven patients ( 18 female , 9 male ; average age 45 years ) were recruited , of whom 14 received pamidronate and 13 received placebo . Overall improvements in pain score , patient 's global assessment of disease severity score , and physical function ( SF-36 ) score were noted in the pamidronate group at 3 months , and improvements in role physical ( SF-36 ) score were noted at 1 and 3 months . There was variability in pamidronate response among individuals . CONCLUSIONS Pamidronate may be a useful treatment option in the management of patients with CRPS Type I. Although treatment response was variable , the majority of patients improved . Early administration in t and em with other treatment measures is recommended Background : The mechanisms underlying neuropathic pain are incompletely understood . Targeting specific molecular mechanisms in the pain signaling system may assist in underst and ing key features in neuropathic pains such as allodynia . This study examined the effect of systemically administered ketamine , an N-methyl-d-aspartate receptor antagonist and lidocaine , a sodium channel blocker , on spontaneous pain , brush-evoked pain , and pinprick-evoked pain in patients with nerve injury pain . Methods : Twenty patients participated in two r and omized , double-blinded , placebo-controlled , crossover experiments in which they , on four different days , received a 30-minute intravenous infusion of ketamine ( 0.24 mg/kg ) , lidocaine ( 5 mg/kg ) , or saline .  Ongoing pain , pain evoked by brush and repetitive pinprick stimuli , and acetone was measured before , during , and after infusion . Results : Ketamine significantly reduced ongoing pain and evoked pain to brush and pinprick , whereas lidocaine only reduced evoked pain to repetitive pinprick stimuli . In individual patients , there was no correlation between the pain-relieving effect of lidocaine and ketamine on ongoing or mechanically evoked pains . Conclusions : N-methyl-d-aspartate receptor-linked systems and sodium channels are involved in generation and maintenance of pain in patients with peripheral nerve injury . It is likely that ongoing pain as well as mechanical hyperalgesia in individual patients is dependent on several separate molecular mechanisms Study Design . A r and omized , controlled , double-blind trial . Objective . To assess the effectiveness of fluoroscopically directed caudal epidural injections in managing chronic low back and lower extremity pain in patients with disc herniation and radiculitis with local anesthetic with or without steroids .  Summary of Background Data . The available literature on the effectiveness of epidural injections in managing chronic low back pain secondary to disc herniation is highly variable . Methods . One hundred twenty patients suffering with low back and lower extremity pain with disc herniation and radiculitis were r and omized to one of the two groups : group I received caudal epidural injections with an injection of local anesthetic , lidocaine 0.5 % , 10 mL ; group II patients received caudal epidural injections with 0.5 % lidocaine , 9 mL , mixed with 1 mL of steroid . The Numeric Rating Scale ( NRS ) , the Oswestry Disability Index 2.0 ( ODI ) , employment status , and opioid intake were utilized with assessment at 3 , 6 , and 12 months posttreatment . Results . The percentage of patients with significant pain relief of 50 % or greater and /or improvement in functional status with 50 % or more reduction in ODI scores was seen in 70 % and 67 % in group I and 77 % and 75 % in group II with average procedures per year of 3.8 ± 1.4 in group I and 3.6 + 1.1 in group II . However , the relief with first and second procedures was significantly higher in the steroid group . The number of injections performed was also higher in local anesthetic group even though overall relief was without any significant difference among the groups . There was no difference among the patients receiving steroids . Conclusion . Caudal epidural injection with local anesthetic with or without steroids might be effective in patients with disc herniation or radiculitis . The present evidence illustrates potential superiority of steroids compared with local anesthetic at 1-year follow-up Background and objective To investigate the effect of intravenous regional anesthesia ( Bier block ) with methylprednisolone and lidocaine in complex regional pain syndrome ( CRPS ) type I in a r and omized , double-blinded , and placebo-controlled study . Methods Twenty-two patients with the diagnosis of CRPS of their upper limb were divided r and omly into 2 groups . The mean age was 22.3 ±1.6 years . Average pain duration was 3.1 ± 1.4 months . In the placebo group ( 10 patients ) , patients received only 100 mL of saline . In the study group ( 12 patients ) , 40 mg of methylprednisolone and 10 mL of 2 % lidocaine were added to the saline . Treatments were applied once a week . Unless significant adverse effects occurred , 3 sessions of blockade were completed . Pain severity , range of motion ( ROM ) , and volumetric edema measurements were obtained before treatment . Pain severity and satisfaction ( resolved , better , no change , or worse ) were recorded after each session . The final assessment was performed 1.5 months later . ROM and volumetric measurements were repeated the day after the block and at the final assessment . Results Differences in pretreatment features of the patients were not statistically significant ( P > .05 ) . In all assessment periods during the study , improvement in pain severity was statistically significant ( P < .05 ) in both groups . This statistically significant difference disappeared at the final assessment ( P > .05 ) . No statistically significant difference was obtained in ROM and volumetric measures in any assessment period before and after the block . Satisfaction scores between the groups were also not different in any assessment period . Conclusions Bier block with methylprednisolone and lidocaine in CRPS type I does not provide long-term benefit in CRPS , and its short-term benefit is not superior to placebo Background Efficacy of epidural local anesthetics plus steroids for the treatment of cervicobrachial pain is uncertain . Methods A prospect i ve study r and omized 160 patients with cervicobrachial pain resistant to conventional therapy . Patients were divided into 4 groups on the basis of the time between pain onset and treatment initiation : group A , 40 patients with pain onset 15 to 30 days ; group B , 40 patients with pain from 31 to 60 days ; group C , 40 patients , 61 to 180 days ; and group D , 40 patients with pain > 180 days . Patients of each group were r and omized to receive an epidural block with bupivacaine and methylprednisolone at intervals of 4 to 5 days ( Single injection ) or continuous epidural bupivacaine every 6 , 12 , or 24 hours plus methylprednisolone every 4 to 5 days ( Continuos epidural ) . The maximum duration of treatment ( 9 blocks in Single injection , and 30 days in Continuos epidural ) was dependent on achieving Pain Control ( PC ) ≥80 % [ PC is defined by this formulae : ( 100 ) (VASinitial−VASfinal)/VASinitial ] . Follow-up at 1 month and 6 months compared PC and the number of pain-free hours of sleep . Results One hundred forty-one patients completed the study . The 4 groups had similar characteristics . At the 1-month and 6-month follow-up analysis based on the time between pain onset and treatment initiation showed that patients of group D , who received the Continuous epidural treatment , had significantly greater PC and significantly more pain-free hours of sleep compared with similar patients in Single injection . Conclusions Therapy with continuous epidural local anesthetic and methylprednisolone provides better control of chronic cervicobrachial pain compared with Single injection . These results are discussed with respect to the possible mechanism of action of the drugs and may relate to the physiopathologic mechanisms associated with neuronal plasticity that result in chronic pain Background : Neuropathic pain in spinal cord injury is a common challenging therapeutic condition . The current study examines the analgesic effect of the sodium channel blocker lidocaine on neuropathic pain in patients with spinal cord injury and the predictive role of concomitant evoked pain on pain relief with lidocaine . Methods : Twenty-four spinal cord injury patients with neuropathic pain at or below the level of injury were r and omized and completed a double-blind crossover trial of 5 mg/kg lidocaine and placebo infused over 30 min . Twelve patients reported evoked pain , and 12 patients had no evoked pain . Spontaneous and evoked pains were assessed using a visual analog scale and quantitative sensory testing . Results : Lidocaine significantly reduced spontaneous pain in all patients ( P < 0.01 ) and in each of the two groups with ( P < 0.01 ) and without ( P = 0.048 ) evoked pain , with no difference in number of responders ( pain reduction ≥ 33 % ) between the patients with ( n = 6 ) and without ( n = 5 ) evoked pain . Lidocaine significantly relieved both at-level and below-level neuropathic pain and decreased brush-evoked dysesthesia but not cold allodynia , pinprick hyperalgesia , or pain evoked by repetitive pinprick . Conclusions : Lidocaine reduced neuropathic pain at and below the level of injury irrespective of the presence or absence of evoked pain . Results are consistent with a central -acting effect of sodium channel blockers acting on neuronal hyperexcitability . Agents ( such as anticonvulsants or antiarrhythmics ) with sodium channel – blocking properties may be a treatment option for spinal cord injury pain Study Design . Clinical practice guideline . Objective . To develop evidence -based recommendations on use of interventional diagnostic tests and therapies , surgeries , and interdisciplinary rehabilitation for low back pain of any duration , with or without leg pain . Summary of Background Data . Management of patients with persistent and disabling low back pain remains a clinical challenge . A number of interventional diagnostic tests and therapies and surgery are available and their use is increasing , but in some cases their utility remains uncertain or controversial . Interdisciplinary rehabilitation has also been proposed as a potentially effective noninvasive intervention for persistent and disabling low back pain . Methods . A multidisciplinary panel was convened by the American Pain Society . Its recommendations were based on a systematic review that focused on evidence from r and omized controlled trials . Recommendations were grade d using methods adapted from the US Preventive Services Task Force and the Grading of Recommendations , Assessment , Development , and Evaluation Working Group . Results . Investigators review ed 3348 abstract s. A total of 161 r and omized trials were deemed relevant to the recommendations in this guideline . The panel developed a total of 8 recommendations . Conclusion . Recommendations on use of interventional diagnostic tests and therapies , surgery , and interdisciplinary rehabilitation are presented . Due to important trade-offs between potential benefits , harms , costs , and burdens of alternative therapies , shared decision-making is an important component of a number of the recommendations A total of 57 patients , aged between 23 and 86 years , with complex regional pain syndrome ( CRPS ) type 1 nine weeks after an isolated closed fracture of the distal radius , was r and omised to receive either serial intravenous regional blockade ( IVRB ) with 15 mg of guanethidine in 30 ml of 0.5 % prilocaine or serial IVRB with 30 ml of normal saline at weekly intervals until the tenderness in their fingers had resolved or they had received a maximum of four IVRBs . The analgesic efficacy was assessed at 24 hours , 48 hours and one week after each procedure by the dolorimetry ratio and verbal pain scores , and at intervals up to six months after the fracture . There was no significant difference in the number of IVRBs administered or in finger tenderness , stiffness or grip strength between the two groups . The guanethidine group experienced more pain in the affected h and ( p = 0.025 ) and at six months had more vasomotor instability ( p < 0.0001 ) compared with the control group . IVRB using guanethidine offers no significant analgesic advantage over a normal saline placebo block in the treatment of early CRPS type 1 of the h and after fracture 
    Output:
    
There is sufficient evidence to support recommendations for some of these interventions for selected neuropathic pain conditions .