***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: Purpose The purpose of this study was to evaluate the clinical effect of electrocautery on the reduction of pain in patellar non-resurfacing bilateral total knee arthroplasty . Material s and Methods A total of 50 patients were enrolled into this study ; all patients had undergone bilateral patellar non-resurfacing total knee arthoplasty at our hospital , between January 2007 to December 2008 . The minimum follow-up period was 1 year . The electrocautery of the patellar rim was performed r and omly on one side only . The clinical results were evaluated between the electrocautery group and the non-electrocautery group based on measures of anterior knee pain , range of motion , American Knee Society clinical rating score , Feller knee score , Western Ontario and McMaster Universities score , and radiographic analysis . Results There were statistically significant differences between preoperative and postoperative status for all parameters . There were no statistically significant differences noted between the electrocautery group and the non electrocautery group for all parameters . Conclusions Electrocautery of patellar rim is thought to be less effective in reducing anterior knee pain OBJECTIVE Anterior knee pain continues to be an important problem following total knee arthroplasty ( TKA ) . The aim of this study was to present the early results of patelloplasty with patellar decompression to relieve anterior knee pain in patients who undergo TKA . METHODS We prospect ively review ed 49 knees from 46 patients ( 35 females , 11 males ; mean age : 69.2 years ; range : 54 to 82 years ) who underwent TKA between January 2004 and December 2008 .  Decompression and patelloplasty were performed in patients in whom Grade 3 and 4 chondropathy was detected during operation according to the Outerbridge classification . All knees were rated according to the Knee Society Knee and Function Scores , before surgery and during the final follow-up . The patella score was evaluated according to a specific patellofemoral pain question naire used by Feller , and the mean knee range of motion was measured preoperatively and postoperatively . Additionally , a patient satisfaction question naire used by Levitsky was performed during the final follow-up exam . The mean follow-up period was 41.1 ( range : 24 to 68 ) months . RESULTS The mean preoperative and final follow-up knee scores were 48.6 ± 8.8 and 87.70 ± 9.3 , and function scores were 48.4 ± 10.4 and 81.4 ± 12.6 , respectively . The mean preoperative patellar score was 18.1 ± 3.5 , and the final follow-up patellar score was 25.7 ± 2.8 . The mean patellar scores were significantly greater in knees with Grade 3 chondropathy compared to Grade 4 chondropathy ( 26.47 ± 2.38 and 24.29 ± 3.19 , respectively ) . Postoperative anterior knee pain was present in four knees ( 8.2 % ) . The mean preoperative knee range of motion was 85.1 ± 12.7 , and the final follow-up knee range of motion was 117.0 ± 9.8 . Patients were " extremely " or " very " satisfied with 93.8 % of their operative outcomes on their knees . CONCLUSION Patellar decompression with patelloplasty in TKA is an option for the reduction of anterior knee pain , but there is a lack of significant evidence in the literature , demonstrating that this method is superior to patellar resurfacing and patellar retention BACKGROUND Anterior knee pain is still a major problem in total knee arthroplasty ( TKA ) . Although the most widely accepted opinion is that anterior knee pain is often associated with a patellofemoral etiology , there is no clear consensus as to etiology or treatment . Disabling pain receptors by electrocautery could theoretically achieve denervation of the anterior knee region . The present prospect i ve r and omized controlled study aim ed to evaluate results after patellar denervation with electrocautery in TKA at a minimum follow-up of 2 years . HYPOTHESIS Patellar denervation provides some benefit in terms of pain and clinical outcomes after TKA without patellar resurfacing . PATIENTS AND METHODS Clinical and radiological results for 35 patients with single-stage bilateral TKA ( 70 knees ; 26 women , nine men ; mean age , 68 years [ range , 58 to 77 years ] ) were review ed . In addition to removal of all osteophytes , patellar denervation by electrocautery was performed on one patella ; and debridement alone , removing all osteophytes , was performed on the contralateral patella , as a control . KSS score and a visual analog scale ( VAS ) were used to assess pre- and postoperative anterior knee pain . RESULTS Mean follow-up was 36 months ( 24 to 60 months ) . No revisions or re-operations were performed . There were no patellar fractures . On all parameters ( KSS score , range of motion and VAS ) , there was a statistically significant pre- to postoperative difference in favor of the denervation group . DISCUSSION Patellar denervation with electrocautery can reduce anterior knee pain , with satisfactory clinical and radiological outcome , in TKA without patellar resurfacing . LEVEL OF EVIDENCE Level II : low-powered prospect i ve r and omized trial Background : Whether to resurface the patella during a primary total knee arthroplasty performed for the treatment of degenerative osteoarthritis remains a controversial issue . Parameters that have been suggested as being useful in guiding this decision include patient height and weight , the presence of anterior knee pain preoperatively , and the grade of chondromalacia encountered intraoperatively . The purpose of this study was to determine whether these parameters were predictive of the clinical result following total knee arthroplasty with or without patellar resurfacing . Methods : Eighty-six patients ( 118 knees ) undergoing primary total knee arthroplasty for the treatment of osteoarthritis were enrolled in a prospect i ve , r and omized , double-blind study . All patients received the same posterior-cruciate-sparing total knee prosthetic components . Patients were r and omized to treatment with or without resurfacing of the patella . Evaluations consisted of the determination of a Knee Society clinical score , the completion of a patient satisfaction question naire , specific questions relating to patellofemoral symptoms , and radiographs .  Sixty-seven patients ( ninety-three knees ) were followed for a minimum of five years ( range , sixty to eighty-four months ; average , 70.5 months ) . Results : With the numbers available , there was no significant difference between the groups treated with and without resurfacing with regard to the overall Knee Society score or the pain and function subscores . Obesity , the degree of patellar chondromalacia , and the presence of preoperative anterior knee pain did not predict postoperative clinical scores or the presence of postoperative anterior knee pain . Conclusions : The occurrence of anterior knee pain could not be predicted with any clinical or radiographic parameter studied . On the basis of these results , it seems likely that postoperative anterior knee pain is related either to the component design or to the details of the surgical technique , such as component rotation , rather than to whether or not the patella is resurfaced We r and omized 126 consecutive patients undergoing primary total knee arthroplasty into group 1 : patella denervation ( n = 63 ) and group 2 : no patella denervation ( n = 63 ) . Assessment was performed preoperatively and at 3 , 12 and 24 months post-operatively . Average follow-up of patients was 26.5 months for denervation group and 26.3 months for no denervation group ( P = 0.84 ) . Pain scores for anterior knee pain were significantly better in the denervation group at 3 months but not at 12 and 24 months . Patient satisfaction was higher in the denervation group . Flexion range was higher in the denervation group at 3 , 12 and 24 months review ( P < 0.01 ) . There were , however , no statistically significant differences with other vali date d knee scores BACKGROUND There is conflicting evidence regarding the merits of patellar resurfacing during total knee arthroplasty , as many of the previous r and omized controlled trials have not been adequately powered . METHODS A pragmatic , multicenter , r and omized controlled trial was initiated in 1999 in the United Kingdom . Within a partial factorial design , 1715 patients were r and omly allocated  to receive or not receive patellar resurfacing during total knee arthroplasty .  The primary outcome measure was the Oxford Knee Score ; secondary measures included the Short Form-12 , the EuroQoL 5D , cost , cost-effectiveness , and the need for subsequent knee surgery . RESULTS The mean Oxford Knee Score was 35 points at five years postoperatively in both groups . There was no significant difference between the groups with respect to the mean Oxford Knee Score ( difference , 0.59 point ; 95 % confidence interval , -0.58 to 1.76 points ) or any other outcome measure at five years postoperatively . The outcome was not affected by whether the patella was domed or anatomic . There was no significant difference between the two groups with respect to the prevalence of knee-related readmission , of minor or intermediate reoperation , or of subsequent patella-related surgery . The total health care cost for the primary arthroplasty , subsequent monitoring , and any revision surgery did not differ significantly between the two groups . CONCLUSIONS In the largest r and omized controlled trial of patellar resurfacing reported to date , the functional outcome , reoperation rate , and total health care cost five years after primary total knee arthroplasty were not significantly affected by the addition of patellar resurfacing to the surgical procedure The efficacy of circumpatellar electrocautery in reducing the incidence of  post-operative anterior knee pain  is unknown . We conducted a single-centre , outcome -assessor and patient-blinded , parallel-group , r and omised , controlled trial to compare circumpatellar electrocautery with no electrocautery in total knee replacement in the absence of patellar resurfacing . Patients requiring knee replacement for primary osteoarthritis were r and omly assigned circumpatellar electrocautery ( intervention group ) or no electrocautery ( control group ) . The primary outcome measure was the incidence of anterior knee pain . A secondary measure was the st and ardised clinical and patient-reported outcomes determined by the American Knee Society scores and the Western Ontario and McMaster Universities ( WOMAC ) osteoarthritis index . A total of 131 knees received circumpatellar electrocautery and 131 had no electrocautery .  The overall incidence of anterior knee pain at follow-up at one year was 26 % ( 20 % to 31 % ) , with 19 % ( 12 % to 26 % ) in the intervention group and 32 % ( 24 % to 40 % ) in the control group ( p = 0.02 ) . The relative risk reduction from electrocautery was 40 % ( 9 % to 61 % ) and the number needed to treat was 7.7 ( 4.3 to 41.4 ) . The intervention group had a better mean total WOMAC score at follow-up at one year compared with the control group ( 16.3 ( 0 to 77.7 ) versus 21.6 ( 0 to 76.7 ) , p = 0.04 ) . The mean post-operative American Knee Society knee scores and function scores were similar in the intervention and control groups ( knee score : 92.4 ( 55 to 100 ) versus 90.4 ( 51 to 100 ) , respectively ( p = 0.14 ) ; function score : 86.5 ( 15 to 100 ) versus 84.5 ( 30 to 100 ) , respectively ( p = 0.49 ) ) . Our study suggests that in the absence of patellar resurfacing electrocautery around the margin of the patella improves the outcome of total knee replacement OBJECTIVE To compare the results of primary total knee arthroplasty with patellar reshaping or resurfacing . METHODS One hundred thirty-three patients were r and omized into patellar reshaping group and patellar resurfacing group . Patellar reshaping includes resecting the partial lateral facet of the patella and the osteophytes surrounding the patella , trimming the patella to match the trochlea of the femoral component . The minimum follow-up time was 7 years . The outcome was measured by anterior knee pain rate , Knee Society clinical score , and radiographs . RESULTS Eight patients in the reshaping group ( 12.5 % ) and 10 patients in the resurfacing group ( 14.7 % ) complained of anterior knee pain ( P=0.712 ) . Meanwhile , there were no significant differences between the two groups in terms of total Knee Society score , Knee Society pain score , Knee Society function score , as well as anterior knee pain rate . CONCLUSIONS With the numbers available , there was no significant difference between the groups treated with patellar reshaping or patellar resurfacing with regard to the KSS , anterior knee pain rate and radiographs . We prefer reshaping the patella to resurfacing the patella because the former preserves sufficient pat 
    Output:
    
However , the OKS ( p = 0.02 ) , patellar score ( p = 0.01 ) , AKSS-Knee Score ( p = 0.004 ) , range of motion ( ROM , p < 0.0001 ) and WOMAC Score ( p = 0.0003 ) indicated that circumpatellarelectrocautery improved clinical outcomes compared with non-electrocautery .
The results indicate that circumferential electrocautery of the patella does not significantly improve AKP compared with non-electrocautery techniques but that circumferential electrocautery significantly improves patients ' knee function after surgery .
Therefore , we believe that circumferential electrocautery is beneficial to the outcome of primary TKR surgery without patellar replacement