***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: In this prospect i ve r and omised study two treatments after non-traumatic medial meniscal tear diagnosed with radiological examination and magnetic resonance imaging were compared ; arthroscopic partial meniscectomy followed by supervised exercise or supervised exercise alone . The aim was to evaluate knee function and physical activity . Ninety patients ( mean age 56 years ) were evaluated using the  Knee Injury and Osteoarthritis Outcome Score , the Lysholm Knee Scoring Scale , the Tegner Activity Scale and a Visual Analogue Scale for knee pain prior to the intervention , after 8 weeks of exercise and after 6 months . According to the outcome scores arthroscopic partial medial meniscectomy combined with exercise did not lead to greater improvement than exercise alone . After the intervention both groups reported decreased knee pain , improved knee function and a high satisfaction ( P < 0.0001 ) . Forty-one per cent of the patients returned to their pre-injury activity level after 6 months . In conclusion , when evaluated with outcome scores , arthroscopic partial medial meniscectomy followed by supervised exercise was not superior to supervised exercise alone in terms of reduced knee pain , improved knee function and improved quality of life We report the results of a prospect i ve longitudinal study of 147 athletes who had had a meniscectomy for an isolated meniscus injury . The patients were review ed in detail after median periods of 4.5 years and 14.5 years and the results analysed . The frequency of complaints related to the operation increased from 53 % at 4.5 years to 67 % at 14.5 years , while demonstrable knee instability increased from 10 % to 36 % . The incidence of radiographic changes of degeneration rose from 40 % to 89 % and at late review 8 % of patients had definite osteoarthritis by the criteria of Ahlbäck ( 1968 ) . In consequence 46 % had given up or reduced their sporting activity , and 6.5 % had changed their occupation . Radiographic deterioration started after the 4.5-year review in 49 % of the patients and was more frequent after lateral than medial meniscectomy Summary Two hundred patients were r and omly selected for either a partial or a total meniscectomy for a meniscal tear during open operation . They were followed for a median of 7.8 years after operation . After partial meniscectomy , posterior horn tears had the worst outcome , but this was only apparent when more than two-thirds of the meniscus had been removed . The amount of meniscal tissue excised was inversely related to the function of the knee , except with bucket-h and le tears treated by partial meniscectomy .  Patients with bucket-h and le , anterior and posterior horn tears had similar functional results after total meniscectomy . Preservation of the peripheral rim of the meniscus following partial meniscectomy produces the best functional results .RésuméDeux  cents patients atteints de lésion méniscale ont été répartis en cours d'opération , de façon r and omisée , entre méniscectomie partielle et méniscectomie totale . Ces patients ont été revus , au dernier examen , de 6.3 à 9.8 ans après l'intervention ( à 7.8 ans en moyenne ) . Après méniscectomie partielle c'étaient les lésions de la corne postérieure qui avaient les moins bons résultats fonctionnels , mais les différences de résultat selon les types de lésion n'étaient observées que lorsque plus d'un tiers de la surface méniscale avait été réséquée . La quantité de tissu méniscal enlevé était inversement proportionnelle à la qualité de la fonction du genou , sauf dans les déchirures en anse de seau traitées par méniscectomie partielle . Ces lésions étaient celles où la plus forte proportion de tissu méniscal avait été réséquée , mais do nt les résultats fonctionnels étaient meilleurs que ceux des lésions de la corne postérieure . Les patients présentant des anses de seau , des lésions de la corne antérieure ou de la corne postérieure , avaient des résultats fonctionnels similaires après méniscectomie totale . La conservation de la périphérie du ménisque après méniscectomie partielle est le facteur essentiel d'un bon résultat fonctionnel post-opératoire Two hundred patients with a meniscus lesion were peroperatively allocated to partial or total meniscectomy . The results were compared at one year and at 6.3 - 9.8 years ( median 7.8 ) . After one year , more patients with  partial meniscectomy  ( 90 % ) than with  total meniscectomy  ( 80 % ) had no complaints ( p = 0.029 ) . At the late review these figures were 62 % and 52 % respectively ( p = 0.18 ) . However , patients with partial meniscectomy had the highest functional scores . In five percent knee joint function had improved and in 35 % deteriorated , in the latter group without detectable difference between partial and total meniscectomy . The incidence of lateral laxity rose from eight to 47 % , most frequently seen after total meniscectomy . During the observation period radiological signs of knee joint degeneration changed from solely joint line narrowing into additional ridge formation and flattening of the femoral condyle , but unrelated to whether partial or total meniscectomy had been performed . Following partial meniscectomy posterior horn lesions had the poorest functional outcome , but only if more than one third of the meniscal surface had been removed . The amount of meniscal tissue excised was inversely correlated to the level of knee joint function except in bucket h and le lesions treated with partial meniscectomy . These lesions had the largest areas of meniscal tissue removed , but higher functional scores than posterior horn lesions . Preservation of the peripheral rim of the meniscus following partial meniscectomy was essential for the functional outcome after surgery Background Repair of meniscal tears is generally preferred over meniscectomy . Hypothesis Repair of unstable bucket-h and le tears of the medial meniscus leads to better outcomes than partial meniscectomy . Study Design Retrospective review of prospect ively collected data . Methods We review ed the records of 155 patients who had isolated bucket-h and le medial meniscal tears and anterior cruciate ligament tears . Fifty-six menisci were repaired ; 99 that were degenerative and crushed beyond repair were removed . Patients were evaluated at a mean follow-up of 6 to 8 years after surgery with the International Knee Documentation Committee examination and a modified Noyes question naire . Results The mean subjective scores were similar for patients in both the repair ( N = 51 ) and meniscectomy ( N = 87 ) groups . However , in the repair group , the mean subjective score of 93.9 for nondegenerative menisci was significantly better than the 87.1 for degenerative menisci . Objective grade s for 25 patients in the repair group were normal or nearly normal in 22 patients ( 88 % ) and for 51 of 56 patients ( 91 % ) in the removal group . Radiographic subscores for the repair group were normal or nearly normal in 23 patients in the repair group and 49 in the removal group . Conclusion Outcomes from meniscal repair were not superior to those from partial removal . Patients with repaired degenerative tears had significantly lower subjective scores than those with nondegenerative tears We have carried out a prospect i ve , longitudinal 30-year review of 95 adolescents who underwent total meniscectomy in one knee  , and have compared the results with those observed 13 years earlier . All the medical records were scrutinised . Of the 63 patients review ed clinical ly , 47 reported decreased sporting activity , although subjective satisfaction rose by 3 % to 71 % . The scores on the WOMAC osteoarthritis index differed significantly between patients grouped by subjective global assessment . Satisfactory function scores increased from 48 % to 60 % . In the 53 patients consenting to bilateral radiography of the knee  , the incidence of narrowing of the articular cartilage in the operated knee increased significantly between the review s ( 19 % to 36 % ) . Progression of degenerative change paralleled reduction in activity . Outcome measures were best after medial , intermediate after lateral and worst after double meniscectomy In order to compare  partial with total meniscectomy  a prospect i ve clinical study of 200 patients was carried out . At arthrotomy 100 patients were allocated to each type of operation . The two groups did not differ in duration of symptoms , age distribution , or sex ratio . The operations were performed as conventional arthrotomies .  One hundred and ninety two of the patients were seen at follow up 2 and 12 months after operation . There was no difference in the period off work between the two groups . One year after operation , 6 of the 98 patients treated with partial meniscectomy had undergone further operation . In all posterior tears were found at both procedures . Among the 94 patients undergoing total meniscectomy  , 4 required further operation . In each , part of the posterior horn had been left at the primary procedure . One year after operation significantly more patients who had undergone partial meniscectomy  had been relieved of symptoms . However , the two groups did not show any difference in the degree of radiological changes present BACKGROUND The efficacy of arthroscopic surgery for the treatment of osteoarthritis of the knee is unknown . METHODS We conducted a single-center , r and omized , controlled trial of arthroscopic surgery in patients with moderate-to-severe osteoarthritis of the knee . Patients were r and omly assigned to surgical lavage and arthroscopic débridement together with optimized physical and medical therapy or to treatment with physical and medical therapy alone . The primary outcome was the total Western Ontario and McMaster Universities Osteoarthritis Index ( WOMAC ) score ( range , 0 to 2400 ; higher scores indicate more severe symptoms ) at 2 years of follow-up . Secondary outcomes included the Short Form-36 ( SF-36 ) Physical Component Summary score ( range , 0 to 100 ; higher scores indicate better quality of life ) . RESULTS Of the 92 patients assigned to surgery , 6 did not undergo surgery . Of the 86 patients assigned to control treatment , all received only physical and medical therapy . After 2 years , the mean ( + /-SD ) WOMAC score for the surgery group was 874+/-624 , as compared with 897+/-583 for the control group ( absolute difference [ surgery-group score minus control-group score ] , -23+/-605 ; 95 % confidence interval [ CI ] , -208 to 161 ; P=0.22 after adjustment for baseline score and grade of severity ) . The SF-36 Physical Component Summary scores were 37.0+/-11.4 and 37.2+/-10.6 , respectively ( absolute difference , -0.2+/-11.1 ; 95 % CI , -3.6 to 3.2 ; P=0.93 ) . Analyses of WOMAC scores at interim visits and other secondary outcomes also failed to show superiority of surgery . CONCLUSIONS Arthroscopic surgery for osteoarthritis of the knee provides no additional benefit to optimized physical and medical therapy . ( Clinical Trials.gov number , NCT00158431 . 
    Output:
    
While an intact meniscus or meniscal repair was generally favorable in the ACL-reconstructed knees , meniscal repair of degenerative meniscal tissue was not favorable .
Although r and omized controlled trials are considered to be the gold st and ard in medical research , a multicenter prospect i ve cohort design may be more appropriate in assessing the long-term outcome of meniscal surgery and the role that multiple preoperative and intraoperative variables may play in clinical outcomes .