***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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    ***EXAMPLES*** 
    Input: 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 & NA ; Complex regional pain syndrome type 1 ( CRPS1 ) involves cortical abnormalities similar to those observed in phantom pain and after stroke . In those groups , treatment is aim ed at activation of cortical networks that subserve the affected limb , for example mirror therapy . However , mirror therapy is not effective for chronic CRPS1 , possibly because movement of the limb evokes intolerable pain . It was hypothesised that preceding mirror therapy with activation of cortical networks without limb movement would reduce pain and swelling in patients with chronic CRPS1 . Thirteen chronic CRPS1 patients were r and omly allocated to a motor imagery program ( MIP ) or to ongoing management . The MIP consisted of two weeks each of a h and laterality recognition task , imagined h and movements and mirror therapy . After 12 weeks , the control group was crossed‐over to MIP . There was a main effect of treatment group ( F(1,11)=57 , P<0.01 ) and an effect size of ∼25 points on the Neuropathic pain scale . The number needed to treat for a 50 % reduction in NPS score was ∼2 . The effect of treatment was replicated in the crossed‐over control subjects . The results uphold the hypothesis that a MIP initially not involving limb movement is effective for CRPS1 and support the involvement of cortical abnormalities in the development of this disorder . Although the mechanisms of effect of the MIP are not clear , possible explanations are sequential activation of cortical pre‐motor and motor networks , or sustained and focussed attention on the affected limb , or both Background . Complex regional pain syndrome type 1 ( CRPSt1 ) of the upper limb is a painful and debilitating condition , frequent after stroke , and interferes with the rehabilitative process and outcome . However , treatments used for CRPSt1 of the upper limb are limited . Objective . This r and omized controlled study was conducted to compare the effectiveness on pain and upper limb function of mirror therapy on CRPSt1 of upper limb in patients with acute stroke . Methods . Of 208 patients with first episode of unilateral stroke admitted to the authors ’ rehabilitation center , 48 patients with CRPSt1 of the affected upper limb were enrolled in a r and omized controlled study , with a 6-month follow-up , and assigned to either a mirror therapy group or placebo control group . The primary end points were a reduction in the visual analogue scale score of pain at rest , on movement , and brush-induced tactile allodynia . The secondary end points were improvement in motor function as assessed by the Wolf Motor Function Test and Motor Activity Log . Results . The mean scores of both the primary and secondary end points significantly improved in the mirror group ( P < .001 ) . No statistically significant improvement was observed in any of the control group values ( P > .001 ) . Moreover , statistically significant differences after treatment ( P < .001 ) and at the 6-month follow-up were found between the 2 groups . Conclusions . The results indicate that mirror therapy effectively reduces pain and enhances upper limb motor function in stroke patients with upper limb CRPSt1 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 Both regional intravenous guanethidine and reserpine have been reported as effective in the treatment of reflex sympathetic dystrophy .  Reserpine depletes storage of norepinephrine , and guanethidine interferes with transport of norepinephrine while depleting storage in the sympathetic nerve terminal . The purpose of this study was to compare drug efficacy in double-blind fashion . Twelve patients , 10 of whom had previous stellate or lumbar sympathetic blocks , were entered into this double-blind cross-over study . Each patient successively received 20 mg guanethidine in 50 ml 0.5 % lidocaine , 1.25 mg reserpine in 50 ml 0.5 % lidocaine , and 50 ml 0.5 % lidocaine with a 1-week interval between medications . At the end of the study and before the code was broken , each patient had the option of continuing treatment with any of the three drugs : the patient merely asked for the first , second , or third drug . Pain assessment used verbal ordinal , numeric , and visual analog scales . Follow-up lasted for a minimum of 6 months . Changes in pain intensity for the first 3 days did not differ significantly among guanethidine , reserpine , and control groups . Pain relief from 2 to 14 months was achieved in two patients receiving reserpine , one receiving guanethidine , and none receiving lidocaine . None of the patients experienced permanent relief . No difference was found between reserpine and guanethidine Background : Phantom limb and complex regional pain syndrome type 1 ( CRPS1 ) are characterized by changes in cortical processing and organization , perceptual disturbances , and poor response to conventional treatments . Grade d motor imagery is effective for a small subset of patients with CRPS1 . Objective : To investigate whether grade d motor imagery would reduce pain and disability for a more general CRPS1 population and for people with phantom limb pain . Methods : Fifty-one patients with phantom limb pain or CRPS1 were r and omly allocated to motor imagery , consisting of 2 weeks each of limb laterality recognition , imagined movements , and mirror movements , or to physical therapy and ongoing medical care . Results : There was a main statistical effect of treatment group , but not diagnostic group , on pain and function . The mean ( 95 % CI ) decrease in pain between pre- and post-treatment ( 100 mm visual analogue scale ) was 23.4 mm ( 16.2 to 30.4 mm ) for the motor imagery group and 10.5 mm ( 1.9 to 19.2 mm ) for the control group . Improvement in function was similar and gains were maintained at 6-month follow-up . Conclusion : Motor imagery reduced pain and disability in these patients with complex regional pain syndrome type I or phantom limb pain , but the mechanism , or mechanisms , of the effect are not clear Shoulder‐h  and syndrome  developed in 36 ( 27 % ) of 132 hemiplegic patients in a prospect i ve study . Subluxation , paresis of the shoulder girdle , moderate spasticity , and deficits in confrontation visual field testing were the major risk factors . In a placebo‐controlled , nonblinded trial , 31 of the 36 patients became almost symptom free within 10 days ' treatment with low doses of oral corticosteroids . Shoulder joint capsules taken at autopsy of 7 patients showed signs of previous trauma of the affected shoulder . In the second part of this study on another 86 patients , early awareness of potential injuries to shoulder joint structures reduced the frequency of shoulder‐h and syndrome from 27 to 8 % . These clinical findings suggest that shoulder‐h and syndrome in hemiplegia is initiated by peripheral lesions . A self‐perpetuating vicious cycle may be established , followed by the clinical picture of a “ reflex sympathetic dystrophy . ” In the majortity of stroke patients , this clinical phenomenon seems to be preventable by avoiding shoulder trauma OBJECTIVE To evaluate the effects of the antiresorptive agent alendronate at a daily oral dose of 40 mg in patients with posttraumatic complex regional pain syndrome type I ( CRPS I ) of the lower extremity . METHODS Forty patients were enrolled in this 8-week r and omized , double-blind , placebo-controlled study of alendronate therapy for CRPS I , a condition associated with regional osteoclastic overactivity . An optional 8-week open extension of alendronate therapy ( weeks 12 - 20 ) was available after a 4-week period without therapy . Clinical assessment s included joint mobility , edema of the lower extremity , tolerance to pressure in the lower extremity , and levels of spontaneous pain . Urinary levels of type I collagen N-telopeptide ( NTX ) were assessed by enzyme-linked immunosorbent assay . Patients were examined at weeks 4 , 8 , 12 , 16 , 20 , and 24 . Statistical analysis included two-way factorial analysis of variance . RESULTS In contrast to placebo-treated patients ( n = 20 ) , all of the alendronate-treated patients ( n = 19 ) exhibited a marked and sustained improvement in levels of spontaneous pain , pressure tolerance , and joint mobility , as well as a significant reduction in urinary levels of NTX at weeks 4 and 8 . The improvement was maintained at week 12 . Twelve patients from each treatment group volunteered for the 8-week open trial , and all of them had a positive response to alendronate . CONCLUSION Our findings support the use of oral alendronate in posttraumatic CRPS I. By reducing local acceleration of bone remodeling , alendronate might relieve pain by effects on nociceptive primary afferents in bone , pain-associated changes in the spinal cord , and possibly also through a central mechanism 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 of the distal radius . It does not improve the outcome of this condition and may delay the resolution of vasomotor instability when compared with the placebo BACKGROUND The pathogenesis of reflex sympathetic dystrophy ( RSD ) is not clear , nor is there a definitive treatment for this syndrome . The morbidity , costs in health care , and loss of work time justify the search for a means to prevent post-traumatic dystrophy . Although the role of toxic oxygen radicals has not yet been clarified , we investigated vitamin C ( ascor 
    Output:
    
RESULTS The review of r and omized controlled trials showed that only bisphosphonates were found to give uniformly positive effects , statistically significantly better than placebo .
Improvement has been reported with  topical dimethyl sulfoxide , systemic steroids , spinal cord stimulation and grade d motor imagery/mirror therapy programmes .
The available evidence does not support the use of other treatments in CRPS , however they are frequently used in clinical practice .
Available evidence , although numerous , does not necessarily reflect what is truly effective and what is sham in the management of CRPS