***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: The purpose of this pilot study was to compare the effectiveness of conservative therapy involving medical exercise therapy ( MET ) versus arthroscopic surgery in patients with knee pain , with MRI-verified degenerative meniscus . The patients were r and omly assigned either to  MET ( n = 9 ) or to  arthroscopic surgery ( n = 8) . Patients receiving MET  had 3 treatments a week for 3 months , a total of 36 treatments . The arthroscopy consisted of meniscectomy with no structured conservative therapy after surgery . Assessment of pain , function , anxiety and depression were performed at inclusion and after 3 months . At the end of treatment , which was 3 months after inclusion , there were no statistical differences between the two groups regarding pain and function . However , anxiety and depression were significantly reduced in the MET group compared with the patients receiving arthroscopic surgery . Bearing in mind the low number of included patients in this pilot study , arthroscopy was found to be no better than MET regarding knee pain and overall daily function . The results from this pilot study are similar to other clinical studies , thereby demonstrating that conservative therapy is just as effective as surgery Background : It is still debated whether a degenerative horizontal tear of the medial meniscus should be treated with surgery . Hypothesis : The clinical outcomes of arthroscopic meniscectomy will be better than those of nonoperative treatment for a degenerative horizontal tear of the medial meniscus . Study Design : R and omized controlled trial ; Level of evidence , 1 . Methods : A total of 102 patients with knee pain and a degenerative horizontal tear of the posterior horn of the medial meniscus on magnetic resonance imaging were included in this study between January 2007 and July 2009 . The study included 81 female and 21 male patients with an average age of 53.8 years ( range , 43 - 62 years ) . Fifty patients underwent arthroscopic meniscectomy ( meniscectomy group ) , and 52 patients underwent nonoperative treatment with strengthening exercises  ( nonoperative group ) . Functional outcomes were compared using a visual analog scale ( VAS ) for pain , Lysholm knee score , Tegner activity scale , and patient subjective knee pain and satisfaction . Radiological evaluations were performed using the Kellgren-Lawrence classification to evaluate osteoarthritic changes . Results : In terms of clinical outcomes , meniscectomy did not provide better functional improvement than nonoperative treatment . At the final follow-up , the average VAS scores were 1.8 ( range , 1 - 5 ) in the meniscectomy group and 1.7 ( range , 1 - 4 ) in the nonoperative group ( P = .675 ) . The average Lysholm knee scores at 2-year follow-up were 83.2 ( range , 52 - 100 ) and 84.3 ( range , 58 - 100 ) in the meniscectomy and nonoperative groups , respectively ( P = .237 ) . In addition , the average Tegner activity scale and subjective satisfaction scores were not significantly different between the 2 groups . Although most patients initially had intense knee pain with mechanical symptoms , both groups reported a relief in knee pain , improved knee function , and a high level of satisfaction with treatment ( P < .05 for all values ) . Two patients in the meniscectomy group and 3 in the nonoperative group with Kellgren-Lawrence grade 1 progressed to grade 2 at the 2-year follow-up . Conclusion : There were no significant differences between arthroscopic meniscectomy and nonoperative management with strengthening exercises in terms of relief in knee pain , improved knee function , or increased satisfaction in patients after 2 years of follow-up BACKGROUND Arthroscopic partial meniscectomy is one of the most common orthopedic procedures , yet rigorous evidence of its efficacy is lacking . METHODS We conducted a multicenter , r and omized , double-blind , sham-controlled trial in 146 patients 35 to 65 years of age who had knee symptoms consistent with a degenerative medial meniscus tear and no knee osteoarthritis . Patients were r and omly assigned to arthroscopic partial meniscectomy or sham surgery . The primary outcomes were changes in the Lysholm and Western Ontario Meniscal Evaluation Tool ( WOMET ) scores ( each ranging from 0 to 100 , with lower scores indicating more severe symptoms ) and in knee pain after exercise ( rated on a scale from 0 to 10 , with 0 denoting no pain ) at 12 months after the procedure . RESULTS In the intention-to-treat analysis , there were no significant between-group differences in the change from baseline to 12 months in any primary outcome . The mean changes ( improvements ) in the primary outcome measures were as follows : Lysholm score , 21.7 points in the partial-meniscectomy group as compared with 23.3 points in the sham-surgery group ( between-group difference , -1.6 points ; 95 % confidence interval [ CI ] , -7.2 to 4.0 ) ; WOMET score , 24.6 and 27.1 points , respectively ( between-group difference , -2.5 points ; 95 % CI , -9.2 to 4.1 ) ; and score for knee pain after exercise , 3.1 and 3.3 points , respectively ( between-group difference , -0.1 ; 95 % CI , -0.9 to 0.7 ) . There were no significant differences between groups in the number of patients who required subsequent knee surgery ( two in the partial-meniscectomy group and five in the sham-surgery group ) or serious adverse events ( one and zero , respectively ) . CONCLUSIONS In this trial involving patients without knee osteoarthritis but with symptoms of a degenerative medial meniscus tear , the outcomes after arthroscopic partial meniscectomy were no better than those after a sham surgical procedure . ( Funded by the Sigrid Juselius Foundation and others ; Clinical Trials.gov number , NCT00549172 . ) Purpose The aim of this prospect i ve r and omized intervention study was to evaluate the outcome at a 2 and 5 year follow-up whether combined arthroscopic surgery followed by exercise therapy was superior to the same exercise therapy alone when treating non-traumatic , degenerative medial meniscal tears . Methods Ninety-six middle-aged patients with MRI-verified degenerative medial meniscus tear and radiographic osteoarthritis grade ≤1 ( Ahlbäck ) participated in the study . Radiographic examination was done before r and omization and after 5 years . The patients were r and omly assigned to either arthroscopic treatment followed by exercise therapy for 2 months or to the same exercise therapy alone . At the start of the study and at the follow-ups at 24 and 60 months the patients answered three question naires KOOS , Lysholm Knee Scoring Scale and Tegner Activity Scale and made pain ratings on the Visual Analogue Scale ( VAS ) . Results Both groups showed highly significant clinical improvements from baseline to the follow-ups at 24 and 60 months on all subscales of KOOS , Lysholm Knee Scoring Scale and VAS ( p < 0.0001 ) . No group differences were found at any of the testing occasions . One third of the patients that were treated with exercise therapy alone did not feel better after the treatment but were improved after arthroscopic surgery . According to radiographic findings two patients from each group had a slight progression of their osteoarthritis after 5 years . Conclusion The findings indicate that arthroscopic surgery followed by exercise therapy was not superior to the same exercise therapy alone for this type of patients . Consequently , exercise therapy can be recommended as initial treatment . However , one third of the patients from the exercise group still had disabling knee symptoms  after exercise therapy but improved to the same level as the rest of the patients after arthroscopic surgery with partial meniscectomy . Level of evidence BACKGROUND Magnetic resonance imaging ( MRI ) of the knee is often performed in patients who have knee symptoms of unclear cause . When meniscal tears are found , it is commonly assumed that the symptoms are attributable to them . However , there is a paucity of data regarding the prevalence of meniscal damage in the general population and the association of meniscal tears with knee symptoms and with radiographic evidence of osteoarthritis . METHODS We studied persons from Framingham , Massachusetts , who were drawn from census-tract data and r and om-digit telephone dialing . Subjects were 50 to 90 years of age and ambulatory ; selection was not made on the basis of knee or other joint problems . We assessed the integrity of the menisci in the right knee on 1.5-tesla MRI scans obtained from 991 subjects ( 57 % of whom were women ) . Symptoms involving the right knee were evaluated by question naire . RESULTS The prevalence of a meniscal tear or of meniscal destruction in the right knee as detected on MRI ranged from 19 % ( 95 % confidence interval [ CI ] , 15 to 24 ) among women 50 to 59 years of age to 56 % ( 95 % CI , 46 to 66 ) among men 70 to 90 years of age ; prevalences were not material ly lower when subjects who had had previous knee surgery were excluded . Among persons with radiographic evidence of osteoarthritis ( Kellgren-Lawrence grade 2 or higher , on a scale of 0 to 4 , with higher numbers indicating more definite signs of osteoarthritis ) , the prevalence of a meniscal tear was 63 % among those with knee pain , aching , or stiffness on most days and 60 % among those without these symptoms . The corresponding prevalences among persons without radiographic evidence of osteoarthritis were 32 % and 23 % . Sixty-one percent of the subjects who had meniscal tears in their knees had not had any pain , aching , or stiffness during the previous month . CONCLUSIONS Incidental meniscal findings on MRI of the knee are common in the general population and increase with increasing age Patient safety in surgery has historically suffered from a lack of physician-driven initiatives aim ed at recognizing , preventing and mitigating medical errors and surgical complications [ 1 ] . In spite of a multiplicity of global patient safety initiatives , m and atory safety protocol s and the introduction of surgical safety checklists , we continue to fall short of protecting our patients from preventable harm [ 2–6 ] . This unrecognized problem has escalated so far that medical errors currently rank as the 3 leading cause of death in the United States [ 7 , 8 ] ( Table 1 ) . Strikingly , in the 21 century , we still have to come to terms with the absurd reality that it is significantly safer to board a commercial airplane , a spacecraft , or a nuclear submarine , than to be admitted to a U.S. hospital [ 9–14 ] . What can surgeons do to protect their patients from the hidden dangers of an imperfect health care system ? The most intuitive solution is to avoid complications originating from surgical treatment that may not be indicated or beneficial for patients in the first place . In other words , avoiding unnecessary surgery could be considered the most pragmatic approach towards reducing preventable surgical complication rates . What do we mean by unnecessary surgery ? We define this as any surgical intervention that is either not needed , not indicated , or not in the patient ’s best interest when weighed against other available options , including conservative measures [ 1 , 15 ] . From a historic perspective , the threat of unnecessary surgery has been publicized as far back as the 1950s , when Dr. Paul Hawley , the Director of the American College of Surgeons ( ACS ) , stated that “ the public would be shocked if it knew the amount of unnecessary surgery performed ( ... ) ” [ 16 ] . More than twenty years later , in 1976 , the American Medical Association ( AMA ) called for a congressional hearing on unnecessary surgery , cl aim ing that there were “ 2.4 million unnecessary operations performed on Americans at a cost of $ 3.9 billion and that 11,900 patients had died from unneeded operations ( ... ) ” [ 17 ] . In 2016 , the existence of unnecessary surgery remains a daunting reality that continues to expose our patients to an unjustified surgical risk [ 18 ] . For example , multiple clinical trials have shown that spinal fusions for back pain do not lead to improved long-term patient outcomes when compared to non-operative treatment modalities , including physical therapy and core strengthening exercises [ 19 , 20 ] . In spite of these insights from high- quality trials , spinal fusion rates continue to dramatically increase in the United States [ 18 ] . Another relevant example is arthroscopic partial meniscectomy , one of the most commonly performed surgical procedures in the world [ 21 ] . This minimally invasive surgery allows treating internal knee damage through small percutaneous skin incisions , with a fast-track postoperative recovery period . In the United States alone , surgeons perform approximately 700,000 arthroscopic partial meniscectomies every year . Strikingly , a recently published prospect i ve r and omized controlled trial ( “ Finnish Degenerative Meniscal Lesion Study ” /FIDELITY trial ) that assessed patient outcomes after arthroscopic meniscal trimming compared to sham surgery revealed no benefit for patients from the routine surgical procedure at 12 months follow-up [ 22 ] . Actually , considering the risk for patients sustaining a severe intraor postoperative complication , no surgical procedure should be considered “ routine ” from the patient ’s perspective [ 23 ] . Yet , until present , a change in practice has not occurred , and arthroscopic meniscectomies continue to be performed on hundreds of thous and s of patients in the United States every year [ 24 , 25 ] . Consider this provocative analogy : If surgery were a pharma 
    Output:
    
The authors concluded that the trial results justify an initial conservative approach using PT in patients with degenerative meniscal tears .
First , if patients do not appear harmed and symptoms appear improved following surgery , surgeons will rely on their prior professional experience to anticipate surgical benefit , when there may be regression to the mean or a placebo effect , rather than benefit from the surgery.16 Second , community norms around the usefulness of the treatment may strengthen the perceived benefit of surgery or encourage continued use because surgery is st and ard of care among surgeons.17 Third , in a health care environment that continues to be based on volume , rather than outcomes or value , financial incentives exist to perform more procedures , sometimes to please the patient or enhance the surgeon ’s prestige or income.18 As long as insurance companies do not limit authorization for these procedures , APM may continue to be used in this patient population .