***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: Background The extended knee lateral midpatellar portal for intraarticular injection of the knee is accurate but is not practical for all patients . We hypothesized that a modified anteriolateral portal where the synovial membrane of the medial femoral condyle is the target would be highly accurate and effective for intraarticular injection of the knee . Methods 83 subjects with non-effusive osteoarthritis of the knee were r and omized to intraarticular injection using the modified anteriolateral bent knee versus the st and ard lateral midpatellar portal . After hydrodissection of the synovial membrane with lidocaine using a mechanical syringe ( reciprocating procedure device ) , 80 mg of triamcinolone acetonide were injected into the knee with a 2.0-in ( 5.1-cm ) 21-gauge needle .  Baseline pain , procedural pain , and pain at outcome ( 2 weeks and 6 months ) were determined with the 10 cm Visual Analogue Pain Score ( VAS ) . The accuracy of needle placement was determined by sonographic imaging . Results The lateral midpatellar and anteriolateral portals result ed in equivalent clinical outcomes including procedural pain ( VAS midpatellar : 4.6 ± 3.1 cm ; anteriolateral : 4.8 ± 3.2 cm ; p = 0.77 ) , pain at outcome ( VAS midpatellar : 2.6 ± 2.8 cm ; anteriolateral : 1.7 ± 2.3 cm ; p = 0.11 ) , responders ( midpatellar : 45 % ; anteriolateral : 56 % ; p = 0.33 ) , duration of therapeutic effect ( midpatellar : 3.9 ± 2.4 months ; anteriolateral : 4.1 ± 2.2 months ; p = 0.69 ) , and time to next procedure ( midpatellar : 7.3 ± 3.3 months ; anteriolateral : 7.7 ± 3.7 months ; p = 0.71 ) . The anteriolateral portal was 97 % accurate by real-time ultrasound imaging . Conclusion The modified anteriolateral bent knee portal is an effective , accurate , and equivalent alternative to the st and ard lateral midpatellar portal for intraarticular injection of the knee . Trial Registration Clinical Trials.gov : OBJECTIVE --To assess the efficacy of a single intra-articular injection of triamcinolone hexacetonide ( THA ) in knee osteoarthritis ( OA ) and examine factors which may relate to treatment efficacy . METHODS --Eighty four patients with clinical and radiographic evidence of knee OA were recruited and r and omly allocated to receive either THA ( 20 mg in 1 ml ) or placebo ( 0.9 % normal saline , 1 ml ) . Follow up assessment s evaluated the following outcome variables : patient opinion of overall change in the treated knee , visual analogue pain score ( VAS ) , distance walked in one minute ( WD ) , and Health Assessment Question naire modified for lower limb function ( HAQ ) . RESULTS --Seventy eight percent of THA and 49 % of placebo treated patients reported overall improvement at week 1 ( p < 0.05 ) . At week 6 , improvement was reported in 57 % and 55 % of patient groups , respectively . VAS improved in both groups at week 1 ( THA , p < 0.001 ; placebo , p < 0.05 ) and week 6 ( both p < 0.01 ) . Improvement in VAS was significantly greater among THA treated patients at week 1 only ( p < 0.01 ) . Subgroup analysis of THA treated patients revealed greater improvement in VAS among patients with clinical evidence of an effusion ( p < 0.05 ) , and those who had synovial fluid successfully aspirated at the time of injection ( p < 0.01 ) . WD improved in THA treated patients at week 1 ( p < 0.001 ) , and in both groups at week 6 ( THA , p < 0.001 ; placebo , p < 0.01 ) . Improvements in HAQ were seen in THA patients only at weeks 1 and 6 ( p < 0.05 ) . Regression analysis did not identify any additional clinical , radiographic , or synovial fluid characteristics which influenced the response . CONCLUSIONS --THA provided short term pain relief in knee OA . Increased benefit was associated with both clinical evidence of joint effusion and successful aspiration of synovial fluid at the time of injection OBJECTIVES : To show whether intra-articular steroid injections are effective in osteoarthritis ; to determine factors that predict response ; and to determine whether injection has a beneficial effect on muscle strength . METHODS : Double blind , placebo controlled , crossover study in 59 patients with symptomatic osteoarthritis of the knee . Outcome measure- Primary outcome measure : change in visual analogue score for pain at three weeks . Predictors of response analysed using logistic regression with a 15 % decrease in pain score at three weeks defining response . RESULTS : Intra-articular methyl prednisolone acetate produced a significant reduction in visual analogue pain score at three weeks compared to both baseline ( median change -2.0 mm , interquartile range -16.25 to 4.0 ) and placebo ( median 0.0 mm , interquartile range -9.0 to 6.25 ) . No clinical predictors of response could be identified . Muscle strength was not significantly improved in the short term by intra-articular injection . CONCLUSIONS : Intra-articular corticosteroids are effective for short term relief of pain in osteoarthritis but predicting responders is not possible . There may be a place for their more widespread use OBJECTIVES Patients with knee osteoarthritis ( OA ) often suffer pain that is not fully controlled by analgesics and often require intra-articular therapies . The aim of this study was to compare the benefits of intra-articular corticosteroid injections ( CSIs ) and tidal irrigation ( TI ) in patients with OA of the knee . METHODS We performed a dual-centre , single blind , r and omised , parallel group trial comparing TI and CSI .  Patients with knee OA were r and omised to either irrigation using a 3.2 mm arthroscope under local anaesthesia or an intra-articular injection of 40 mg triamcinolone acetonide and 1 % lidocaine . Patients were followed for 6 months . The primary outcome measure was the Western Ontario and McMaster Universities OA Index total pain score ( visual analogue scale , VAS ) . RESULTS One hundred and fifty patients were recruited of whom 71 received TI and 79 CSI . In both treatment groups , over 80 % of patients reported improvement at 2 and 4 weeks . After this time , the benefit of CSI decreased whereas that of TI was maintained : at 26 weeks the pain relief afforded by TI was significantly greater than that of CSI . At 26 weeks 29 % of the CSI group reported improvement vs 64 % of the TI group ( P<0.001 ) . Patients with a knee effusion responded better to both treatments , however , this was most apparent for CSI . Patients with less severe radiographic OA also obtained the greatest improvement from both treatments . CONCLUSION Both procedures lead to significant short-term pain relief of at least 4 weeks , however , TI displayed a significantly greater duration of benefit .  Patients with effusions and milder radiographic change obtained the best response to treatment Objective . To assess whether inflammation on ultrasound is predictive of clinical response to intraarticular ( IA ) corticosteroid injections in patients with knee osteoarthritis ( OA ) . Methods . Patients with symptomatic knee OA were r and omized to receive either an IA injection of 40 mg triamcinolone acetonide in the treatment group or 1 cc 0.9 % saline in the placebo group . Clinical response was assessed by changes in baseline Western Ontario and McMaster Universities ( WOMAC ) index scores and physician global assessment at 4 and 12 weeks . Ultrasounds were performed at each visit . Patients and assessors were blinded to treatment status . Results . Seventy-nine patients were enrolled into the study . Four-week data were available for 67 patients in the primary analysis comparing change in WOMAC pain score from baseline to 4 weeks . There was almost no change in the WOMAC pain subscale score from baseline to 4 weeks in the control group , but there was a significant improvement in WOMAC pain subscale score from 10.8 ( SD ± 3.2 ) at baseline to 8.75 ( SD ± 4.0 ) at 4 weeks in the treatment group ( adjusted p = 0.001 ) . Of the 34 patients in the treatment group ; 16 ( 47 % ) had inflammatory disease and 18 ( 53 % ) had noninflammatory disease as determined by ultrasound . There was no difference in the change in WOMAC pain score between the inflammatory and noninflammatory patients in the treatment group at 4 weeks . There was a statistically significant greater improvement in pain subscale scores among noninflammatory patients than among inflammatory patients at 12 weeks . Conclusion . Intraarticular corticosteroid injections are an effective short-term treatment for symptomatic knee OA compared to placebo . Patients with noninflammatory characteristics on ultrasound had a more prolonged benefit from IA corticosteroids compared to inflammatory patients OBJECTIVE To assess the efficacy of intra-articular steroid injections following arthroscopy and joint lavage in symptomatic OA of the knee . METHODS Seventy-seven patients with OA of the knee were r and omized to receive either 120 mg methylprednisolone acetate ( MPA ) or placebo following arthroscopy . Clinical assessment s included severity of pain on movement and at rest , stiffness , the presence of joint effusions , range of movement , WOMAC ( Western Ontario and McMaster Universities Osteoarthritis Index ) score and Lequesne functional assessment . The outcome measures were evaluated at baseline and 2 , 4 , 8 , 12 and 24 weeks . Further arthroscopies and synovial biopsies were performed at the time of clinical response and at relapse . RESULTS An intention-to-treat analysis was performed on 71 patients ( 38 MPA , 33 placebo ) . Using the OARSI ( Osteoarthritis Research Society International ) response criteria , 58 % of the steroid group vs 33 % of the placebo group ( adjusted relative risk = 2.38 ) ( P = 0.004 ) responded at 4 weeks . At other time points , there were no significant differences between the treatment groups . There were no significant differences between the two treatment groups for pain , stiffness or WOMAC or Lequesne assessment s at any time point . CONCLUSIONS The response to intra-articular corticosteroids following joint lavage is short-lived ( 2 - 4 weeks ) , achievement of an OARSI response criterion being the only difference between the two groups OBJECTIVE To evaluate the efficacy of joint lavage and intraarticular steroid injection , alone and in combination , in the treatment of patients with symptomatic knee osteoarthritis ( OA ) . METHODS Ninety-eight patients with painful tibiofemoral OA were enrolled in a prospect i ve , r and omized , controlled , 2 x 2 factorial- design trial of 6 months ' duration . The 4 treatment groups consisted of 1 ) intraarticular placebo ( 1.5 ml of 0.9 % normal saline ) , 2 ) intraarticular corticosteroids ( 3.75 mg of cortivazol in 1.5 ml ) , 3 ) joint lavage and intraarticular placebo , and 4 ) joint lavage and intraarticular corticosteroid . Outcome measures evaluated at baseline , week 1 , week 4 , week 12 , and week 24 included severity of pain ( 100-mm visual analog scale [ VAS ] ) , global status ( 100-mm VAS ) , and Lequesne 's functional index . RESULTS No interaction between steroid injection and joint lavage was demonstrated . Patients who had undergone joint lavage had significantly improved pain VAS scores at week 24 ( P = 0.020 ) . In contrast , corticosteroid injection had no long-term effect ( P = 0.313 ) ; corticosteroid injection was associated with a decrease in pain only at week 1 ( P = 0.003 ) and week 4 ( P = 0.020 ) . After week 4 , Lequesne 's functional index was not significantly improved regardless of the assigned treatment . CONCLUSION Compared with placebo , both treatments significantly relieved pain but did not improve functional impairment . The effects of the 2 treatments were additive . Cortivazol provided short-term relief of pain ( up to week 4 ) . The effects of joint lavage persisted up to week 24 OBJECTIVE To evaluate the safety and efficacy of long-term intraarticular ( IA ) steroid injections for  knee pain related to osteoarthritis ( OA ) . METHODS In a r and omized , double-blind trial , 68 patients with OA of the knee received IA injections of triamcinolone acetonide 40 mg ( 34 patients ) or saline ( 34 patients ) into the study knee every 3 months for up to 2 years . The primary outcome variable was radiologic progression of joint space narrowing of the injected knee after 2 years . Measurements of minimum joint space width were performed by an automated computerized method 
    Output:
    
Data from individual publications , although not consistent across studies , suggest that the presence of effusion , withdrawal of fluid from the knee , severity of disease , absence of synovitis , injection delivery under US guidance and greater symptoms at baseline may all improve the likelihood of response to IASI .
Such data would help in better targeting therapy to those most likely to benefit