Raine Sihvonen

Arthroscopic Partial Meniscectomy versus Sham Surgery for a Degenerative Meniscal Tear

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, randomized, 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 randomly 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; ClinicalTrials.gov number, NCT00549172.).

Double-bundle anterior cruciate ligament reconstruction using hamstring autografts and bioabsorbable interference screw fixation: prospective, randomized, clinical study with 2-year results.

Background Conventional anterior cruciate ligament reconstruction techniques have focused on restoration of the anterome-dial bundle only, which, however, may be insufficient in restoring the rotational stability of the knee. Hypothesis Rotational stability of the knee is better when using a double-bundle technique instead of a single-bundle technique for anterior cruciate ligament reconstruction. Study Design Randomized controlled clinical trial; Level of evidence, 1. Methods Seventy-seven patients were randomized into 3 different groups for anterior cruciate ligament reconstruction with hamstring tendons: double-bundle with bioabsorbable screw fixation (n = 25), single-bundle with bioabsorbable screw fixation (n = 27), and single-bundle with metallic screw fixation (n = 25). The evaluation methods were clinical examination, KT-1000 arthrometric measurement, and the International Knee Documentation Committee and Lysholm knee scores. Results There were no differences between the study groups preoperatively. Seventy-three patients (95%) were available at a minimum 2-year follow-up (range, 24–35 mo). The rotational stability of the knee, as evaluated by the pivot-shift test, was the best in the patients in the double-bundle group. In addition, the patients in the single-bundle groups had more graft failures than those in the double-bundle group. Concerning the anterior stability of the knee as measured with the KT-1000 arthrometer, the group differences were not statistically significant. No significant differences were found between the groups in knee scores. Conclusion Rotational stability of the knee is better when using the double-bundle technique instead of the single-bundle technique in anterior cruciate ligament reconstruction.

Blinded interpretation of study results can feasibly and effectively diminish interpretation bias

OBJECTIVE Controversial and misleading interpretation of data from randomized trials is common. How to avoid misleading interpretation has received little attention. Herein, we describe two applications of an approach that involves blinded interpretation of the results by study investigators. STUDY DESIGN AND SETTINGS The approach involves developing two interpretations of the results on the basis of a blinded review of the primary outcome data (experimental treatment A compared with control treatment B). One interpretation assumes that A is the experimental intervention and another assumes that A is the control. After agreeing that there will be no further changes, the investigators record their decisions and sign the resulting document. The randomization code is then broken, the correct interpretation chosen, and the manuscript finalized. Review of the document by an external authority before finalization can provide another safeguard against interpretation bias. RESULTS We found the blinded preparation of a summary of data interpretation described in this article practical, efficient, and useful. CONCLUSIONS Blinded data interpretation may decrease the frequency of misleading data interpretation. Widespread adoption of blinded data interpretation would be greatly facilitated were it added to the minimum set of recommendations outlining proper conduct of randomized controlled trials (eg, the Consolidated Standards of Reporting Trials statement).

Finnish Degenerative Meniscal Lesion Study (FIDELITY): a protocol for a randomised, placebo surgery controlled trial on the efficacy of arthroscopic partial meniscectomy for patients with degenerative meniscus injury with a novel ‘RCT within-a-cohort’ study design

Introduction Arthroscopic partial meniscectomy (APM) to treat degenerative meniscus injury is the most common orthopaedic procedure. However, valid evidence of the efficacy of APM is lacking. Controlling for the placebo effect of any medical intervention is important, but seems particularly pertinent for the assessment of APM, as the symptoms commonly attributed to a degenerative meniscal injury (medial joint line symptoms and perceived disability) are subjective and display considerable fluctuation, and accordingly difficult to gauge objectively. Methods and analysis A multicentre, parallel randomised, placebo surgery controlled trial is being carried out to assess the efficacy of APM for patients from 35 to 65 years of age with a degenerative meniscus injury. Patients with degenerative medial meniscus tear and medial joint line symptoms, without clinical or radiographic osteoarthritis of the index knee, were enrolled and then randomly assigned (1 : 1) to either APM or diagnostic arthroscopy (placebo surgery). Patients are followed up for 12 months. According to the prior power calculation, 140 patients were randomised. The two randomised patient groups will be compared at 12 months with intention-to-treat analysis. To safeguard against bias, patients, healthcare providers, data collectors, data analysts, outcome adjudicators and the researchers interpreting the findings will be blind to the patients’ interventions (APM/placebo). Primary outcomes are Lysholm knee score (a generic knee instrument), knee pain (using a numerical rating scale), and WOMET score (a disease-specific, health-related quality of life index). The secondary outcome is 15D (a generic quality of life instrument). Further, in one of the five centres recruiting patients for the randomised controlled trial (RCT), all patients scheduled for knee arthroscopy due to a degenerative meniscus injury are prospectively followed up using the same protocol as in the RCT to provide an external validation cohort. In this article, we present and discuss our study design, focusing particularly on the internal and external validity of our trial and the ethics of carrying out a placebo surgery controlled trial. Ethics and dissemination The protocol has been approved by the institutional review board of the Pirkanmaa Hospital District and the trial has been duly registered at ClinicalTrials.gov. The findings of this study will be disseminated widely through peer-reviewed publications and conference presentations. Trial registration ClinicalTrials.gov, number NCT00549172.

All-Inside Meniscal Repair With Bioabsorbable Meniscal Screws or With Bioabsorbable Meniscus Arrows A Prospective, Randomized Clinical Study With 2-Year Results

Background All-inside meniscal repairs have gained popularity in the past few years. However, only a few prospective, randomized clinical studies have been done to compare different all-inside meniscal repair techniques. Hypothesis Meniscal repair with bioabsorbable meniscal screws and arrows results in similar clinical outcome on short-term follow-up. Study Design Randomized controlled trial; Level of evidence, 2. Methods Forty-two patients were prospectively randomized to have all-inside meniscal repair either by using bioabsorbable meniscal screws or bioabsorbable meniscus arrows (21 patients, 23 meniscal repairs in each group) for the fixation. The evaluation methods were clinical examination, Lysholm score, the International Knee Documentation Committee (IKDC) knee score, and magnetic resonance arthrography (MRA) evaluation. The average follow-up time was 27 months (standard deviation, 8). Results There were no differences between the study groups preoperatively. All 42 patients (100%) were available for the follow-up. However, during the follow-up, 11 patients had clinical failure, confirmed at second-look arthroscopy, of the repair leading to partial meniscal resection. Four failures (all on the medial meniscus) were observed with the use of meniscal screw fixation (17%), and 7 (4 on the medial meniscus, and 3 on the lateral meniscus) with the use of meniscus arrow fixation (30%) (P = .242). Six patients with meniscus arrows (29%) had chondral damage on the femoral condyles evaluated by MRA or at second-look arthroscopy, while none of the patients with the meniscal screws had the same (P = .018). However, the Lysholm and the IKDC scores were similar in both groups at follow-up. Conclusion All-inside meniscal repair with bioabsorbable meniscal screws and arrows resulted in similar clinical outcome, although significantly more chondral damage was observed when using bioabsorbable meniscus arrows for fixation.

Changes in rates of arthroscopy due to degenerative knee disease and traumatic meniscal tears in Finland and Sweden

Background and purpose — Knee arthroscopy is commonly performed to treat degenerative knee disease symptoms and traumatic meniscal tears. We evaluated whether the recent high-quality randomized control trials not favoring arthroscopic surgery for degenerative knee disease affected the procedure incidence and trends in Finland and Sweden. Patients and methods — We conducted a bi-national registry-based study including all adult (aged ≥18 years) inpatient and outpatient arthroscopic surgeries performed for degenerative knee disease (osteoarthritis (OA) and degenerative meniscal tears) and traumatic meniscal tears in Finland between 1997 and 2012, and in Sweden between 2001 and 2012. Results — In Finland, the annual number of operations was 16,389 in 1997, reached 20,432 in 2007, and declined to 15,018 in 2012. In Sweden, the number of operations was 9,944 in 2001, reached 11,711 in 2008, and declined to 8,114 in 2012. The knee arthroscopy incidence for OA was 124 per 105 person-years in 2012 in Finland and it was 51 in Sweden. The incidence of knee arthroscopies for meniscal tears coded as traumatic steadily increased in Finland from 64 per 105 person-years in 1997 to 97 per 105 person-years in 2012, but not in Sweden. Interpretation — The incidence of arthroscopies for degenerative knee disease declined after 2008 in both countries. Remarkably, the incidence of arthroscopy for degenerative knee disease and traumatic meniscal tears is 2 to 4 times higher in Finland than in Sweden. Efficient implementation of new high-quality evidence in clinical practice could reduce the number of ineffective surgeries.

Validation of the Western Ontario Meniscal Evaluation Tool (WOMET) for patients with a degenerative meniscal tear: a meniscal pathology-specific quality-of-life index.

BACKGROUND Arthroscopic partial meniscectomy is the most common orthopaedic procedure and is often carried out to treat a degenerative meniscal lesion. The purpose of the present study was to determine the psychometric properties of the Western Ontario Meniscal Evaluation Tool (WOMET) for patients with an arthroscopically verified degenerative meniscal tear. METHODS Four hundred and eighty-five patients with an arthroscopically verified degenerative meniscal tear were included. Two groups of patients were formed: one consisted of 385 patients for the purpose of psychometric testing of the WOMET and the other consisted of 100 patients for the assessment of criterion validity. The reliability of the WOMET questionnaire was assessed by determining both internal consistency and test-retest repeatability; for the latter, a subgroup of forty patients completed the form two weeks preoperatively and again on the day of the operation. Validity assessment included determination of content validity (floor and ceiling effects), criterion validity (completion of the WOMET, the Lysholm knee score, and a generic quality-of-life questionnaire by a group of 100 patients), and construct validity (hypothesis testing). Finally, the responsiveness of the WOMET was determined with two successive assessments (on the day of surgery and six months postoperatively). RESULTS The WOMET showed acceptable internal consistency, test-retest reliability, floor and ceiling effects, criterion validity (agreement with both Lysholm and 15-D scores), and construct validity (all hypotheses were significant). The WOMET was also found to be responsive to change. CONCLUSION The WOMET score demonstrated acceptable psychometric performance as a patient-administered outcome measure for patients with an arthroscopically verified degenerative meniscal tear.

Arthroscopy for degenerative knee—a difficult habit to break?

Patients with degenerative musculoskeletal disease are the largest group referred for orthopedic consultation. The prevailing understanding regarding the etiology, pathogenesis, diagnosis, and treatment of many degenerative musculoskeletal problems is very similar: pain is usually attributable to a mechanical problem—for example, an impinging acromion in the shoulder or femoroacetabular impingement in the hip, degenerative and herniated intervertebral discs, or a degenerative meniscus tear in the knee. This has led to a relatively straightforward diagnostic and treatment strategy for these complaints: attempts at non-operative treatment are usually followed quite soon after by surgical intervention that usually aims to “restore deranged anatomy” by removing degenerative tissue. Many patients report improvement after such surgery, but similar results have also been obtained with nonoperative treatment in randomized, non-placebo controlled trials. Despite the considerable clinical and economic implications, the evidence on the true efficacy of many orthopedic procedures is at best scarce. The efficacy of any given surgery cannot be addressed simply by evaluating the outcome of patients who have undergone the procedure, as the role of the underlying disease process (e.g., the natural course of the disease, regression to mean, and fluctuations in symptoms), the placebo effects, and the possible beneficial effects of the actual surgical procedure cannot be disentangled from each other with such a study design (Krogsboll et al. 2009). However, one particular trial published some 10 years ago marked an important turning point for the orthopedic community as a whole. Using a sham-surgery controlled design, Moseley and colleagues showed that arthroscopic lavage or debridement provides no benefit over a placebo procedure (skin incisions only) in patients with advanced knee osteoarthritis (Moseley et al. 2002). Quite understandably, such a finding—one that essentially eroded the justification of a very common orthopedic procedure—was met with unprecedented criticism and even hostility. There were, however, a few colleagues who chose a different path: rather than resorting to challenging Moseley’s findings solely with no or low-level evidence, they put the procedure to the only proper test, a randomized controlled trial (RCT). The resulting high-quality RCTs corroborated the general finding that “arthroscopic surgery” is no better than either physiotherapy or sham surgery in patients with various degrees of knee OA and meniscal “tear” (Herrlin et al. 2007, 2013, Kirkley et al. 2008, Katz et al. 2013, Sihvonen et al. 2013, Yim et al. 2013). Given the massive clinical experience on arthroscopic surgery for degenerative knee disease (at least 2 million such procedures are carried out annually around the world with generally highly satisfactory outcome) and the convincing biological rationale behind the procedure, the reservations among our peers are easily understandable. But are they justified? In assessing this, we note that meniscal tears are found on MRI in every third knee in individuals from the general population aged 50–90 years. In those who have radiographic evidence of osteoarthritis (whether they have knee symptoms or not), the prevalence of a meniscal tear is even higher (> 60%). In other words, the more severe the radiographic osteoarthritis, the higher the prevalence of “degenerative meniscus tear” (Englund et al. 2008). Importantly, most meniscal tears are found in people without any knee pain. Also, having knee pain and a meniscal tear does not necessarily mean the tear is the cause of the pain, as the evidence convincingly shows that there are other sources of knee pain (Englund et al. 2012). But has all this evidence resulted in a reversal of clinical practice? In this issue of Acta Orthopaedica, Thorlund et al. (2014) report nationwide statistics on the annual incidence of meniscal procedures in the years 2000–2011 in Denmark. The national database used for the analysis contains all healthcare procedures performed in public and private hospitals and clinics, and thus enables reliable estimation of trends in knee arthroscopy. The age, sex, and diagnosis are also recorded, and accordingly, this database enables the identification/differentiation of patients with traumatic tears (who are generally younger) from middle-aged patients with degenerative tear and/or knee OA (acknowledging the inherent problems due to the lack of universally accepted criteria/coding for “degenerative” or “traumatic” tears, and for knee OA). The data of Thorlund et al. show a paradoxical association between evidence and clinical practice in arthroscopic surgery for patients with symptomatic degenerative knee disease, as a large increase in meniscal procedures was observed in patients aged 35 years or more during the study period. In contrast, the incidence rate of meniscal procedures in patients aged 35 or less was stable over the same time period. Although the paper is probably the most methodologically sound (using nationwide statistics with almost 100% coverage), it is not the first to report similar trends in knee arthroscopy. In 2011, Kim et al. reported a large increase in knee arthroscopies in middle-aged patients (most being meniscectomies) from 1996 to 2006 based on the nationally representative sample of hospital-based and freestanding ambulatory surgery centers in the USA (Kim et al. 2011). Earlier this year, Lazic et al. (2014) reported a more than 2-fold increase in the incidence of arthroscopic meniscal resections performed from 2000 to 2012 based on hospital records of all patients over 60 years of age admitted to National Health Service (NHS) hospitals in the UK, including outpatient appointments (Lazic et al. 2014). In both of these studies, the large increases in the incidence of meniscectomies were reflected by decreases (between 30% and 80%) in the numbers of arthroscopic procedures for established knee OA (lavage or debridement) (Kim et al. 2011, Lazic et al. 2014). In essence, from these studies it appears that while the incidence of the procedures for younger patients with meniscal injury has been relatively stable, the incidence of procedures for middle-aged patients with degenerative knee disease (meniscus tear with or without knee OA) has increased substantially. It seems that orthopedic surgeons are unmoved by the pivotal trials (Moseley et al. 2002, Herrlin et al. 2007, Kirkley et al. 2008) and are still scoping the same patients and their knees, yet possibly coding the procedure differently (Kim et al. 2011). Is it time to abandon ship? We would argue that the amount of quality evidence on the benefit of arthroscopic surgery for a degenerative knee is second to none among all orthopedic complaints. And quite extraordinarily, that evidence is also very uniform, pointing in one and the same direction. Despite all this, it is readily apparent that the vast majority of our peers still consider the existing evidence insufficient to cause a major shift in the current practice of treating patients with a degenerative knee disease (Price and Beard 2014, Rossi et al. 2014). If so, we feel that at the very least, the present situation supplies very convincing leverage, and an ethical justification, to start carrying out whatever type of randomized controlled trial one might consider appropriate to prove the efficacy of knee arthroscopy. We believe that the weight of the evidence is causing the current ship of state to lean over badly and may soon require us to abandon the vessel unless new and more convincing research comes to the rescue. It may be that funding authorities will choose to stop paying for these surgeries unless more buoyant and countervailing evidence can be brought to bear. Encouragingly, some have assessed the dangers and have launched new RCTs on the topic (Hare et al. 2013, Giori, Stensrud), operating under the principle that reliable evidence on the use of very common medical procedures is absolutely vital for keeping our healthcare systems sustainable and productive. Thorlund and colleagues are to be praised for their important contribution in the pursuit of more cost-effective practice in arthroscopic knee surgery, perhaps helping us to navigate safely and sustainably.

Correspondence: Arthroscopic Partial Meniscectomy for Degenerative Meniscal Tear

To the Editor: Previous studies have suggested that partial meniscectomy has little benefit in patients with advanced osteoarthritis1,2 but some benefit in those with mild-to-moderate osteoarthritis.3 Sihvonen and colleagues (Dec. 26 issue)4 attempted to assess the benefit of partial meniscectomy in patients without osteoarthritis. However, although the authors excluded patients with radiographic degenerative changes, the declaration of “no knee osteoarthritis” is misleading. It is important to note that patients in this study did have cartilage degeneration. In fact, 80% of the patients in the partial-meniscectomy group and 67% of those in the sham group had degenerative or osteoarthritic changes on diagnostic arthroscopy. In addition, patients with traumatic tears or mechanical symptoms were excluded, yet this is probably the group that would benefit most from arthroscopic partial meniscectomy.5 Lastly, magnetic resonance imaging (MRI) was not used to exclude or stratify patients according to factors such as subchondral edema or chondromalacia. We submit that arthroscopy remains an effective treatment for meniscal tears in selected patients. Surgical decision making should be individualized, including consideration of mechanical symptoms, degenerative versus traumatic meniscal tear, and other pain generators, including the degree of arthritis.Dr. Stuart reports receiving consulting fees and royalties from Arthrex and Stryker, and receiving research funding from Stryker; and Dr. Levy, receiving consulting fees and royalties from Arthrex and VOT Solutions, and receiving research funding from Arthrex, Biomet, and Stryker. No other potential conflict of interest relevant to this letter was reported.

A positive viewpoint regarding arthroscopy for degenerative knee conditions

Sir—In the latest issue of Acta Orthopaedica, Thorlund et al. (2014) report figures from the Danish National Patient Register (DNPR) showing a 2-fold increase in knee arthroscopy with meniscal surgery from 2000 to 2011, and they conclude that arthroscopy for degenerative conditions in particular has increased in the middle-aged population. In a guest editorial in the same issue, Jarvinen et al. (2014; from Finland and Sweden) conclude that since any additional effect of arthroscopic operations in these conditions has not been shown, that arthroscopy is contraindicated, and that political decisions may be the next step to stop arthroscopic operations. In Thorlund’s article, 2 significant confounders are of importance for the results and conclusions. The authors state that in the year 2000, several hospitals did not report to the DNPR and they suggest an under-reporting rate of about 5%, based on a general estimate of all operations. This cannot be extrapolated to knee arthroscopy, which is a small operation that is performed more often in private hospitals and in orthopedic specialist practices (often under local anesthesia) than in public hospitals, in contrast to larger operations. Private hospitals and clinics did not report to the DNPR before the mid-2000s. Therefore, the increase between 2000 and 2011 is substantially overestimated; the authors could have contacted the Danish National Board of Health to make the estimate of missing operations more qualified. Alternatively, the authors could have excluded hospitals and clinics that did not report over the whole period of 11 years. It is a mistake to regard meniscal changes coded as DM232 as degenerative. The distinction between DS832 and DM232 is only related to the duration of symptoms, and most clinicians would use 3 months as the dividing time. In addition, the salary for diagnosing and non-operatively treating meniscal changes is higher if the code DM23.2 is used, which may make clinicians aware of the time consideration regarding individual patients. Thus, how many of the meniscal operations were actually performed on degenerative meniscal changes and how many were performed on traumatic ruptures is pure speculation. Although it is not stated clearly in Thorlund’s article, we assume that the incidences are based on population numbers for each age category and not for the whole population. On the internet, it is easy to obtain numbers of inhabitants in Denmark for every 3 months—and with 1-year age intervals (http://www.statistikbanken.dk/02). If this information had been used, the extrapolation that is used for population numbers in the article could have been avoided. Is it bad to arthroscope and debride knees with meniscal or degenerative changes? The “well-conducted” randomized studies have all shown an effect, but have not been able to demonstrate any difference between operative and non-operative treatments. No one has had a control group (with no treatment). Thus, there may not be any difference, or the outcome measures that are used in these studies, which are generally constructed for much more painful conditions, might not be relevant or sensitive enough for people with milder disease to show any difference. But the randomized studies show that arthroscopy has an effect—which is not less than non-operative treatment. Another important issue with the data from these randomized studies is that they contain too few patients to be able to perform relevant subgroup analysis. From clinical experience, we know that male patients with mechanical symptoms have very good outcome compared to female patients without mechanical symptoms. In the editorial, Jarvinen et al. (2014 state – quite strangely – that on top of no difference, there are complications to arthroscopy. In well-conducted randomized studies, these complications are included in the outcome comparisons. Jarvinen et al. missed 2 very important points that should have been considered before they abandoned arthroscopy for the degenerative knee. Firstly, the number of people who engaged in regular sports activity increased by 30% in Denmark between 1998 and 2011; in the middle-aged group, almost 70% had regular physical activity and 42% had sports activity 3–4 hours a week or more (Laub 2013). 20% of adults must stop sports because of health problems. Symptoms from degenerative conditions are load-related, and it could be expected that higher numbers of middle-aged people would have symptoms from their knees in 2011 than in 2000, just because of the substantially increased physical activity in this age group. In addition, this can be expected to increase over the coming years. The second point has, strangely enough, not been part of this discussion at any time. What if non-operative treatment is not working? There has been an annual increase in public physiotherapy treatment in Denmark of 3–5 % every year from 2000 to 2011 ([Praksisplan for fysioterapi] Reports from the Danish regions 2012–13), particularly in the middle-aged population. The total amount of physiotherapy and other non-operative interventions has most probably increased much more, as many Danes obtained a private health insurance during this period. So there is quite substantial data on a marked increase in non-operative treatments of the degenerative knee during the period in question. So, banning arthroscopy is not based on scientific evidence but has a much more political sound. For us as clinicians seeing many of these patients, in contrast to several of the authors of the articles that have created this debate, it is evident that most patients have tried relevant non-operative interventions before they are seen by the orthopedic surgeon. There is an increasing demand to stay fit and to be able to engage in physical activity irrespective of age, and the general health benefits of this have been substantially documented. A large proportion of these patients are very fit, and for them it is difficult to argue for further exercise as treatment. We suggest that, instead of closing one eye and pressing the patients into the same standard protocol, the healthcare staff should evaluate the individual person. A fit 50-year-old plumber who is in danger of loosing his job because of knee pain from mild cartilage changes and meniscal flaps, might be helped most quickly with an arthroscopic debridement. An unfit, overweight person might best be treated with muscle training and weight loss. And a person who has become fit from training and has lost weight etc., should not be kept from the possibility of arthroscopic debridement when non-operative treatment has failed. Clinicians know that the situation of failed non-operative treatment is very common. Knee arthroscopy is one option among several in treatment of the degenerative knee. Based on the available data outlined above and our long clinical experience, it is our view that in Denmark the use of arthroscopy has not increased more than non-operative treatments (and probably less). We feel that increases in the numbers of treatments (both operative and non-operative) must be expected during the coming years, and these are important modalities to keep the Danish population physically active as they get older. This benefits everyone, and also the public finances.