***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: Background Total hip or knee replacement is highly successful when judged by prosthesis-related outcomes . However , some people experience long-term pain . Objectives To review published studies in representative population s with total hip or knee replacement for the treatment of osteoarthritis reporting proportions of people by pain intensity . Data sources MEDLINE and EMBASE data bases search ed to January 2011 with no language restrictions . Citations of key articles in ISI Web of Science and reference lists were checked . Study eligibility criteria , participants and interventions Prospect i ve studies of consecutive , unselected osteoarthritis patients representative of the primary total hip or knee replacement population , with intensities of patient-centred pain measured after 3 months to 5-year follow-up . Study appraisal and synthesis methods Two authors screened titles and abstract s. Data extracted by one author were checked independently against original articles by a second . For each study , the authors summarised the proportions of people with different severities of pain in the operated joint . Results Search es identified 1308 articles of which 115 reported patient-centred pain outcomes .  Fourteen articles describing 17 cohorts ( 6 with hip and 11 with knee replacement ) presented appropriate data on pain intensity . The proportion of people with an unfavourable long-term pain outcome in studies ranged from about 7 % to 23 % after hip and 10 % to 34 % after knee replacement . In the best quality studies , an unfavourable pain outcome was reported in 9 % or more of patients after hip and about 20 % of patients after knee replacement . Limitations Other studies reported mean values of pain outcomes . These and routine clinical studies are potential sources of relevant data . Conclusions and implication s of key findings After hip and knee replacement , a significant proportion of people have painful joints . There is an urgent need to improve general awareness of this possibility and to address determinants of good and bad outcomes Pain control is necessary for successful rehabilitation and outcome after total knee arthroplasty . Our goal was to compare the clinical efficacy of periarticular injections consisting of a long-acting local anesthetic ( ropivacaine ) and epinephrine with and without combinations of an α2-adrenergic agonist ( clonidine ) and /or a nonsteroidal anti-inflammatory agent ( ketorolac ) . In a double-blinded controlled study , we r and omized 160 patients undergoing total knee arthroplasty to receive 1 of 4 intraoperative periarticular injections : Group A , ropivacaine , epinephrine , ketorolac , and clonidine ; Group B , ropivacaine , epinephrine , and ketorolac ; Group C , ropivacaine , epinephrine , and clonidine ; Group D ( control ) , ropivacaine and epinephrine . Compared with Group D , Group A and B patients had significantly lower postoperative visual analog pain scores and nurse pain assessment and Group C patients had a significantly greater reduction in physical therapist pain assessment . We found no differences in other parameters analyzed Although the analgesic effects of periarticular multimodal drug injection ( PMDI ) after TKA have been well documented , there is little information about additional pain relieving effects of PMDI incorporated to contemporary multimodal pain control protocol s which have been proved to provide excellent analgesia . We performed a parallel-group , r and omised , controlled study to determine whether PMDI provides additional clinical benefits on contemporary multimodal analgesic protocol s including preemptive analgesics , continuous femoral nerve block , and IV-PCA . Eighty-seven patients were r and omized to a PMDI group ( n=45 ) or to a No-PMDI group ( n=42 ) .  Pain level and opioid consumption were compared as primary outcomes . The incidences of narcotic and ropivacaine related side effects and complications , functional recovery , and satisfaction were also compared . The PMDI group experienced less pain during the operation night and the 1st postoperative day and showed lower opioid consumption over 24h after surgery . However , the PMDI group had a higher VAS pain score on the 1st postoperative day than during the operation night . No group differences in side-effects and complication incidences , functional recovery , and satisfaction were found . This study demonstrates that PMDI provides additional pain relief and reduces opioid consumption only during the early postoperative period in patients managed by the contemporary pain management protocol following TKA Background Several reports have confirmed the ability of intraoperative periarticular injections to control pain after THA . However , these studies used differing combinations of analgesic agents and the contribution of each , including the local anesthetic agent , is uncertain . Underst and ing the independent effects of the various agents could assist in improved pain management after surgery . Questions / purpose sWe therefore determined the ability of intraoperative periarticular infiltration of levobupivacaine to ( 1 ) reduce postoperative pain , ( 2 ) reduce postoperative morphine requirements , and ( 3 ) reduce the incidence of nausea and urinary retention . Patients and Methods A double-blinded , r and omized , placebo-controlled trial of patients undergoing primary THAs was performed . Patients were r and omized to receive a periarticular infiltration of 150 mg levobupivacaine in 60 mL 0.9 % saline ( n = 45 ) or a placebo consisting of 60 mL 0.9 % saline ( n = 46 ) . We obtained a short-form McGill pain score , visual analog scale ( VAS ) , and morphine requirements via patient-controlled analgesia ( PCA ) as primary measures . Postoperative antiemetic requirements and need for catheterization for urinary retention were determined as secondary measures . Results Subjectively reported pain scores and the overall intensity scores were similar for both groups in the postoperative period . At the same time the mean morphine consumption was less in the levobupivacaine group , most notable in the first 12 hours after surgery : treatment group 11.5 mg vs control group 21.2 mg . We observed no differences in the frequency of postoperative nausea and vomiting or urinary retention . Conclusions Our observations suggest periarticular injection of levobupivacaine can supplement available postoperative analgesic techniques and reduce postoperative morphine requirements after THA.Level of Evidence Level I , therapeutic study . See Guidelines for Authors for a complete description of levels of evidence Background and Objectives : High-volume local infiltration analgesia ( LIA ) is widely applied as part of a multimodal pain management strategy in total hip arthroplasty ( THA ) . However , method ological problems hinder the exact interpretation of previous trials , and the evidence for LIA in THA remains to be clarified . Therefore , we evaluated whether intraoperative high-volume LIA , in addition to a multimodal oral analgesic regimen , would further reduce acute postoperative pain after THA . Methods : Patients scheduled for unilateral , primary THA under spinal anesthesia were included in this r and omized , double-blind , placebo-controlled trial receiving high-volume ( 150 mL ) wound infiltration with ropivacaine 0.2 % with epinephrine ( 10 & mgr;g/mL ) or saline 0.9 % . A multimodal oral analgesic regimen consisting of slow-release acetaminophen 2 g , celecoxib 400 mg , and gabapentin 600 mg was instituted preoperatively . Rescue analgesic consisted of oral oxycodone .  Pain was assessed repeatedly the first 8 hrs after surgery using the 100-mm visual analog scale . The primary end point was pain during walking ( 5 m ) 8 hrs after surgery . Secondary end points were pain at rest , pain on 45 degrees of passive flexion of the hip with the leg straight , and cumulative consumption of oxycodone .  Results : A total of 120 patients were included .  Pain during walking ( median [ interquartile range ] [ 95 % confidence interval ] ) was low in the ropivacaine versus the placebo group ( 20 [ 14 - 38 ] [ 0 - 93 ] vs 22 [ 10 - 40 ] [ 0 - 83 ] ) and did not differ significantly ( P = 0.71 ) . Consumption of rescue oxycodone  ( 5 mg [ 0 - 10 mg ] [ 0 - 24 mg ] vs 10 mg [ 0 - 15 mg ] [ 0 - 29 mg ] ) did not differ ( P = 0.45 ) . Conclusions : Intraoperative high-volume LIA with ropivacaine 0.2 % provided no additional reduction in acute pain after THA when combined with a multimodal oral analgesic regimen consisting of acetaminophen , celecoxib , and gabapentin and is therefore not recommended This study tests the null hypothesis that there is no difference between sciatic nerve block ( SNB ) and periarticular anesthetic infiltration ( PI ) as adjuncts to femoral nerve blockade ( FNB ) in total knee arthroplasty in terms of postoperative opioid requirements . Fifty-two patients undergoing total knee arthroplasty were r and omized to receive either ( a ) combined FNB-SNB or ( b ) combined FNB-PI .  Average morphine consumption in the first 24 ( 20 vs 23 mg ) and 48 hours ( 26 vs 33 mg ) showed no significant difference . Visual Analogue Scale scores , knee flexion ( 60 ° vs 67.5 ° ) and extension lag ( 0 ° vs 5 ° ) were comparable . Anesthetic time , surgical time , and length of hospital stay ( 5.5 vs 6 days ) were similar . This study showed no significant difference between the 2 groups . The PI offers a practical and potentially safer alternative to SNB Purpose Several analgesic techniques are available for pain management after a major operation . Material s and Methods From December 2005 to February 2006 , a prospect i ve , double-blind study was performed involving 90 patients who had undergone a total knee arthroplasty . Patients were r and omly divided into three equal groups ( n = 30 ) . Demographic data , including age , height , weight , knee score , visual analogue scale ( VAS ) , and range of flexion were evaluated preoperatively . Before wound closure , patients were given intra-synovial injections of the following solutions : patients in group I received 40 mL of 300 mg ropivacaine with 1 : 200,000 epinephrine and 5 mg morphine ; patients in Group II received 40 mL of 300 mg ropivacaine with epinephrine ; and patients in Group III received 50 mL normal saline as a control . All patients received an epidural patient-controlled analgesia ( PCA ) for 24 postoperative hours . Analgesic efficacy was evaluated using the VAS at intervals of 2 , 4 , 6 , 12 , 24 , 32 , 40 , and 48 hours postoperatively . During this period , the side effects , the dosage of rescue analgesia required , and the range of knee flexion were recorded for each group . Results There were no significant differences among the three groups with regards to the VAS and the required dose of rescue analgesia ( p > 0.05 ) . None of the groups demonstrated significant differences in the range of knee flexion and the incidence of postoperative nausea and emesis ( p > 0.05 ) . Conclusion Therefore , we found that ropivacaine , alone or with morphine , injected into the synovial tissue , along with an epidural PCA has no additional benefits in pain control after a total knee arthroplasty Background For the majority of patients with osteoarthritis ( OA ) , joint replacement is a successful intervention for relieving chronic joint pain . However , between 10 - 30 % of patients continue to experience chronic pain after joint replacement . Evidence suggests that a risk factor for chronic pain after joint replacement is the severity of acute post-operative pain . The aim of this r and omised controlled trial ( RCT ) is to determine if intra-operative local anaesthethic wound infiltration additional to a st and ard anaethesia regimen can reduce the severity of joint pain at 12-months after total knee replacement ( TKR ) and total hip replacement ( THR ) for OA . Methods 300 TKR patients and 300 THR patients are being recruited into this single-centre double-blind RCT . Participants are recruited before surgery and r and omised to either the st and ard care group or the intervention group . Participants and outcome assessors are blind to treatment allocation throughout the study . The intervention consists of an intra-operative local anaesthetic wound infiltration , consisting of 60 mls of 0.25 % bupivacaine with 1 in 200,000 adrenaline . Participants are assessed on the first 5 days post-operative , and then at 3-months , 6-months and 12-months . The primary outcome is the WOMAC Pain Scale , a vali date d measure of joint pain at 12-months . Secondary outcomes include pain severity during the in-patient stay , post-operative nausea and vomiting , satisfaction with pain relief , length of hospital stay , joint pain and disability , pain sensitivity , complications and cost-effectiveness . A nested qualitative study within the RCT will examine the acceptability and feasibility of the intervention for both patients and healthcare professionals . Discussion Large-scale RCTs assessing the effectiveness of a surgical intervention are uncommon , particulary in orthopaedics . The results from this trial will inform evidence -based recommendations for both short-term and long-term pain management after lower limb joint replacement . If a local anaesthetic wound infiltration is found to be an effective and cost-effective intervention , implementation into clinical practice could improve long-term pain outcomes for patients 
    Output:
    
There was no evidence of pain control additional to that provided by femoral nerve block .
Conclusions Local anaesthetic infiltration is effective in reducing short-term pain and hospital stay in patients receiving THR and TKR .