Arthroscopic partial meniscectomy for the degenerative meniscus tear: a comparison of patients included in RCTs and prospective cohort studies.

BACKGROUND AND PURPOSE: Concerns exist regarding the generalizability of results from randomized controlled trials (RCTs) evaluating arthroscopic partial meniscectomy (APM) to treat degenerative meniscus tears. It has been suggested that study populations are not representative of subjects selected for surgery in daily clinical practice. Therefore, we aimed to compare patients included in trials and prospective cohort studies that received APM for a degenerative meniscus tear. PATIENTS AND METHODS: Individual participant data from 4 RCTs and 2 cohort studies undergoing APM were collected. 1,970 patients were analyzed: 605 patients included in RCTs and 1,365 included in the cohorts. We compared patient and disease characteristics, knee pain, overall knee function, and health-related quality of life at baseline between the RCT and cohort groups using standardized differences, ratios comparing the variance of continuous covariates, and graphical methods such as quantile-quantile plots, side-by-side boxplots, and non-parametric density plots. RESULTS: Differences between RCT and the cohort were observed primarily in age (younger patients in the cohort; standardized difference: 0.32) and disease severity, with the RCT group having more severe symptoms (standardized difference: 0.38). While knee pain, overall knee function, and quality of life generally showed minimal differences between the 2 groups, it is noteworthy that the largest observed difference was in knee pain, where the cohort group scored 7 points worse (95% confidence interval 5-9, standardized difference: 0.29). CONCLUSION: Patients in RCTs were largely representative of those in cohort studies regarding baseline scores, though variations in age and disease severity were observed. Younger patients with less severe osteoarthritis were more common in the cohort; however, trial participants still appear to be broadly representative of the target population.

Evaluation of the changes in incidence and patient age of knee arthroscopy along with changes in time between knee arthroscopy and arthroplasty between 1998 and 2018: a nationwide register study.

BACKGROUND: Recent evidence has led to guidelines to refrain from recommending knee arthroscopy for patients with an osteoarthritis diagnosis. The aim of this study was to evaluate the latest changes in the incidence of arthroscopic surgery for degenerative knee disease, changes in the ages of those patients and the delay between knee arthroscopy and arthroplasty, in Finland between 1998 and 2018. METHOD: The data for were collected from the Finnish National Hospital Discharge Register (NHDR). All knee arthroplasties and arthroscopies performed due to osteoarthritis, degenerative meniscal tears, and traumatic meniscal tears were included. Incidence rates (per 100,000 person-years) as well as the median age of patients were calculated. RESULTS: The incidence of arthroscopy decreased 74% (413 to 106 per 100,000 person-years) and knee arthroplasty increased 179% (94 to 262 per 100,000 person-years) between 1998 and 2018. The incidence of all arthroscopies increased until 2006. Subsequently, the incidence of arthroscopy due to OA decreased by 91% and arthroscopic partial meniscectomy (APM) for degenerative meniscal tears decreased by 77% until 2018. The decrease of traumatic meniscal tears begun later, leading to decrease of 57% between 2011 and 2018. Conversely, the incidence of patients undergoing APM of traumatic meniscal tear increased 375%. The median age of patients who underwent knee arthroscopy decreased from 51 to 46 and from 71 to 69 in knee arthroplasty patients. CONCLUSIONS: Increasing evidence that recommends refraining from knee arthroscopy in OA and degenerative meniscal tears has led to a dramatic decrease in the incidence of arthroscopies. Simultaneously, the median age of the patients who undergo these operations has continued to decrease.

Effect of Osteochondroplasty on Time to Reoperation After Arthroscopic Management of Femoroacetabular Impingement: Analysis of a Randomized Controlled Trial.

Background: A subset of patients with femoroacetabular impingement (FAI) fail arthroscopic management. It is not clear which patients will fail surgical management; however, several surgical and patient factors, such as type of procedure and age, are thought to be important predictors. Purpose: This time-to-event analysis with a 27-month follow-up analysis compared the effect of (1) arthroscopic osteochondroplasty with or without labral repair versus (2) arthroscopic lavage with or without labral repair on the time to reoperation in adults aged 18 to 50 years with FAI. Study Design: Randomized controlled trial; Level of evidence, 1. Methods: Eligible participants had been randomized in a previous study trial to a treatment of arthroscopic osteochondroplasty or arthroscopic lavage with or without labral repair. Using the comprehensive data set from the Multinational Femoroacetabular Impingement Randomized controlled Trial, all reoperations until 27 months after surgery were identified. The analysis was conducted using a Cox proportional hazards model, with percentage of patients with a reoperation evaluated in a time-to-event analysis as the outcome. The independent variable was the procedure, with age and impingement subtype explored as potential covariates. The effects from the Cox model were expressed as the hazard ratio (HR). All tests were 2-sided, with an alpha level of .05. Results: A total of 108 patients in the osteochondroplasty group and 106 patients in the lavage group were included. The mean age of the patients included in the study was 36 ± 8.5 years. Overall, 27 incident reoperations were identified within the 27-month follow-up, with an incidence rate of 6 per 100 person-years. Within the osteochondroplasty group, 8 incident reoperations were identified (incidence rate, 3.4 per 100 person-years), while within the lavage group, 19 incident reoperations were identified (incidence rate, 8.7 per 100 person-years). The hazard of reoperation for patients undergoing osteochondroplasty was 40% of that of patients undergoing lavage (HR, 0.40 [95% CI, 0.17-0.91] P = .029). Conclusion: This study demonstrated that for adults between the ages of 18 and 50 years with FAI, arthroscopic osteochondroplasty was associated with a 2.5-fold decrease in the hazard of reoperation at any point in time compared with arthroscopic lavage. Registration: NCT01623843 (ClinicalTrials.gov identifier).

Osteochondroplasty and Labral Repair for the Treatment of Young Adults With Femoroacetabular Impingement: A Randomized Controlled Trial.

BACKGROUND: Femoroacetabular impingement (FAI) is a condition known to cause hip pain in young adults. PURPOSE: To evaluate the efficacy of the surgical correction of FAI via arthroscopic osteochondroplasty with or without labral repair compared with arthroscopic lavage of the hip joint with or without labral repair. STUDY DESIGN: Randomized controlled trial; Level of evidence, 1. METHODS: A total of 220 male and female participants aged 18 to 50 years with nonarthritic FAI suitable for surgical treatment were recruited for the trial at 10 clinical centers in Canada, Finland, and Denmark between October 2012 and November 2017, of whom 214 were included in the final analysis. In the osteochondroplasty group, cam- and/or pincer-type lesions were resected using fluoroscopic guidance. In the lavage group, the joint was washed out with 3 L of normal saline. Surgeons were instructed to repair the labrum in both groups if it was mechanically unstable once probed, showing visible displacement or chondrolabral separation. The primary outcome was patient-reported pain (using the 100-point visual analog scale [VAS]) at 12 months. Secondary outcomes included hip function (Hip Outcome Score [HOS] and International Hip Outcome Tool), physical and mental health (12-Item Short Form Health Survey), and health utility (EuroQol-5 Dimensions) at 12 months as well as any reoperations and other hip-related adverse events at 24 months. RESULTS: At 12 months, there was no difference in pain (VAS) between the groups (mean difference [MD], 0.11 [95% CI, -7.22 to 7.45]; P = .98). Also, 88.3% (189/214) of participants had a labral tear, of which 60.3% were repaired. For the secondary outcomes, there were no significant differences between treatment groups, with the exception of the HOS activities of daily living domain in which lavage showed significant improvement compared with osteochondroplasty (MD, -5.03 [95% CI, -10.40 to -0.03]; P = .049). By 24 months, there were significantly fewer reoperations reported in the osteochondroplasty group (8/105) than the lavage group (19/104) (odds ratio, 0.37 [95% CI, 0.15-0.89]; P = .026). The primary reasons for a reoperation included hip pain (15/27; 55.6%) and a reinjury of the labrum (11/27; 40.7%). CONCLUSION: Both the osteochondroplasty and the lavage groups with or without labral repair for FAI had significantly improved pain or function significantly at 1 year. By 2 years, the reoperation rate was significantly lower in the osteochondroplasty group. REGISTRATION: NCT01623843 (ClinicalTrials.gov identifier).

Arthroscopic partial meniscectomy for a degenerative meniscus tear: a 5 year follow-up of the placebo-surgery controlled FIDELITY (Finnish Degenerative Meniscus Lesion Study) trial.

OBJECTIVES: To assess the long-term effects of arthroscopic partial meniscectomy (APM) on the development of radiographic knee osteoarthritis, and on knee symptoms and function, at 5 years follow-up. DESIGN: Multicentre, randomised, participant- and outcome assessor-blinded, placebo-surgery controlled trial. SETTING: Orthopaedic departments in five public hospitals in Finland. PARTICIPANTS: 146 adults, mean age 52 years (range 35-65 years), with knee symptoms consistent with degenerative medial meniscus tear verified by MRI scan and arthroscopically, and no clinical signs of knee osteoarthritis were randomised. INTERVENTIONS: APM or placebo surgery (diagnostic knee arthroscopy). MAIN OUTCOME MEASURES: We used two indices of radiographic knee osteoarthritis (increase in Kellgren and Lawrence grade ≥1, and increase in Osteoarthritis Research Society International (OARSI) atlas radiographic joint space narrowing and osteophyte sum score, respectively), and three validated patient-relevant measures of knee symptoms and function (Western Ontario Meniscal Evaluation Tool (WOMET), Lysholm, and knee pain after exercise using a numerical rating scale). RESULTS: There was a consistent, slightly greater risk for progression of radiographic knee osteoarthritis in the APM group as compared with the placebo surgery group (adjusted absolute risk difference in increase in Kellgren-Lawrence grade ≥1 of 13%, 95% CI -2% to 28%; adjusted absolute mean difference in OARSI sum score 0.7, 95% CI 0.1 to 1.3). There were no relevant between-group differences in the three patient-reported outcomes: adjusted absolute mean differences (APM vs placebo surgery), -1.7 (95% CI -7.7 to 4.3) in WOMET, -2.1 (95% CI -6.8 to 2.6) in Lysholm knee score, and -0.04 (95% CI -0.81 to 0.72) in knee pain after exercise, respectively. The corresponding adjusted absolute risk difference in the presence of mechanical symptoms was 18% (95% CI 5% to 31%); there were more symptoms reported in the APM group. All other secondary outcomes comparisons were similar. CONCLUSIONS: APM was associated with a slightly increased risk of developing radiographic knee osteoarthritis and no concomitant benefit in patient-relevant outcomes, at 5 years after surgery. TRIAL REGISTRATION: ClinicalTrials.gov (NCT01052233 and NCT00549172).

Statistical analysis plan for the 5-year and 10-year follow-up assessments of the FIDELITY trial.

BACKGROUND: The research objectives of the 5-year and 10-year assessments in the Finnish degenerative meniscal lesion study (FIDELITY) are twofold: (1) to assess the long-term efficacy of arthroscopic partial meniscectomy (APM) in adults (age 35 to 65 years) with a degenerative meniscus tear and (2) to determine the respective effects of APM and degenerative meniscus tear on the development of radiographic and clinical knee osteoarthritis (OA). METHODS AND DESIGN: FIDELITY is an ongoing multi-center, randomized, participant and outcome assessor blinded, placebo-surgery-controlled trial in 146 patients. This statistical analysis plan (SAP) article describes the overall principles for analysis of long-term outcomes (5-year and 10-year follow up), including how participants will be included in each analysis, the primary and secondary outcomes and their respective analyses, adjustments for covariates, and the presentation of the results. In addition, we will present the planned sensitivity and subgroup analyses. DISCUSSION: To assess the long-term efficacy of APM on knee symptoms and function we are carrying out a long-term (5-year and 10-year) follow up of our placebo-surgery-controlled FIDELITY trial according to statistical principles outlined in detail in this document. As our second primary objective, whether APM (resection of torn meniscus tear) accelerates or delays the development of knee osteoarthritis in patients with an arthroscopically verified degenerative tear of the medial meniscus, a pre-registered follow-up is also carried out. TRIAL REGISTRATION: ClinicalTrials.gov, NCT00549172 (Arthroscopy in the Treatment of Degenerative Medial Meniscus Tear). Registered on 25 October 2007 (NCT00549172). ClinicalTrials.gov, NCT01052233 (Development of Knee Osteoarthritis After Arthroscopic Partial Resection of Degenerative Meniscus Tear). Registered on 20 January 2010.

Arthroscopic partial meniscectomy versus placebo surgery for a degenerative meniscus tear: a 2-year follow-up of the randomised controlled trial.

OBJECTIVE: To assess if arthroscopic partial meniscectomy (APM) is superior to placebo surgery in the treatment of patients with degenerative tear of the medial meniscus. METHODS: In this multicentre, randomised, participant-blinded and outcome assessor-blinded, placebo-surgery controlled trial, 146 adults, aged 35-65 years, with knee symptoms consistent with degenerative medial meniscus tear and no knee osteoarthritis were randomised to APM or placebo surgery. The primary outcome was the between-group difference in the change from baseline in the Western Ontario Meniscal Evaluation Tool (WOMET) and Lysholm knee scores and knee pain after exercise at 24 months after surgery. Secondary outcomes included the frequency of unblinding of the treatment-group allocation, participants' satisfaction, impression of change, return to normal activities, the incidence of serious adverse events and the presence of meniscal symptoms in clinical examination. Two subgroup analyses, assessing the outcome on those with mechanical symptoms and those with unstable meniscus tears, were also carried out. RESULTS: In the intention-to-treat analysis, there were no significant between-group differences in the mean changes from baseline to 24 months in WOMET score: 27.3 in the APM group as compared with 31.6 in the placebo-surgery group (between-group difference, -4.3; 95% CI, -11.3 to 2.6); Lysholm knee score: 23.1 and 26.3, respectively (-3.2; -8.9 to 2.4) or knee pain after exercise, 3.5 and 3.9, respectively (-0.4; -1.3 to 0.5). There were no statistically significant differences between the two groups in any of the secondary outcomes or within the analysed subgroups. CONCLUSIONS: In this 2-year follow-up of patients without knee osteoarthritis but with symptoms of a degenerative medial meniscus tear, the outcomes after APM were no better than those after placebo surgery. No evidence could be found to support the prevailing ideas that patients with presence of mechanical symptoms or certain meniscus tear characteristics or those who have failed initial conservative treatment are more likely to benefit from APM.

Bioabsorbable Versus Metal Screw in the Fixation of Tibial Tubercle Transfer: A Cadaveric Biomechanical Study.

BACKGROUND: In tibial tubercle transfer (TTT) procedures, the osteotomized and transferred tibial tubercle is usually fixed into the host bone using metal screws. PURPOSE: To compare the strength of fixation provided by a single bioabsorbable screw versus a metal screw for TTT. STUDY DESIGN: Controlled laboratory study. METHODS: Twenty-two pairs of human cadaveric tibiae were used to compare the fixation strength of a single 4.5-mm bicortical bioabsorbable or metal screw for TTT. In our 2-phase biomechanical testing protocol, the specimens were first subjected to a cyclic-loading test (1500 loading cycles between 50 and 300 N at 0.5 Hz frequency), after which they were loaded to failure (single-cycle load-to-failure test). To control for possible differences in bone quality, volumetric bone mineral density was determined using peripheral quantitative computed tomography. RESULTS: No significant displacement differences were observed between the 2 groups for the cyclic-loading test. In the subsequent single-cycle load-to-failure test, the mean yield load was 566 ± 234 N in the bioabsorbable screw group and 984 ± 630 N in the metal screw group (P = .002). The failure mode of bioabsorbable screws was breakage and/or bending, and that of metal screws was bending and/or pull-out. Bone density was similar in the 2 groups. CONCLUSION: A metal screw seems to provide greater fixation strength than a biodegradable screw in the TTT of a human cadaveric knee. However, considering the maximum quadriceps pull in vivo, the strength of fixation provided by a biodegradable screw seems clinically sufficient. CLINICAL RELEVANCE: Bioabsorbable screws, particularly if used in duplicate, could provide a viable option for metal screws in TTT fixation.

Mechanical Symptoms and Arthroscopic Partial Meniscectomy in Patients With Degenerative Meniscus Tear: A Secondary Analysis of a Randomized Trial.

BACKGROUND: Recent evidence shows that arthroscopic partial meniscectomy (APM) offers no benefit over conservative treatment of patients with a degenerative meniscus tear. However, patients who report mechanical symptoms (sensations of knee catching or locking) may benefit from APM. OBJECTIVE: To assess whether APM improves mechanical symptoms better than sham surgery. DESIGN: Randomized, patient- and outcome assessor-blinded, sham surgery-controlled, multicenter trial. (ClinicalTrials.gov: NCT00549172). SETTING: 5 orthopedic clinics in Finland. PATIENTS: Adults (aged 35 to 65 years) with a degenerative medial meniscus tear and no knee osteoarthritis. INTERVENTION: APM or sham surgery. MEASUREMENTS: Patients' self-report of mechanical symptoms before surgery and at 2, 6, and 12 months after surgery. RESULTS: 70 patients were randomly assigned to APM, and 76 were assigned to sham surgery. Thirty-two patients (46%) in the APM group and 37 (49%) in the sham surgery group reported catching or locking before surgery; the corresponding numbers at any follow-up were 34 (49%) and 33 (43%), with a risk difference of 0.03 (95% CI, -0.06 to 0.12). In the subgroup of 69 patients with preoperative catching or locking, the risk difference was 0.07 (CI, -0.08 to 0.22). LIMITATION: Analyses were post hoc, and the results are only generalizable to knee catching and occasional locking because few patients reported other types of mechanical symptoms. CONCLUSION: Resection of a torn meniscus has no added benefit over sham surgery to relieve knee catching or occasional locking. These findings question whether mechanical symptoms are caused by a degenerative meniscus tear and prompt caution in using patients' self-report of these symptoms as an indication for APM. PRIMARY FUNDING SOURCE: Academy of Finland.

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 10(5) 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 10(5) person-years in 1997 to 97 per 10(5) 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.

Uni- and bipolar hemiarthroplasty with a modern cemented femoral component provides elderly patients with displaced femoral neck fractures with equal functional outcome and survivorship at medium-term follow-up.

INTRODUCTION: The choice between unipolar and bipolar hemiarthroplasty for treatment of displaced intracapsular femoral neck fractures in elderly patients still remains controversial. Our objective was to compare series of elderly individuals with a displaced femoral neck fracture treated with either a cemented, modular unipolar or bipolar prosthesis with the same femoral component. MATERIALS AND METHODS: A prospective, randomized controlled trial of 175 displaced intracapsular femoral neck fractures in patients over 65 years was randomly allocated to unipolar (88) and to bipolar (87) hemiarthroplasty group. The primary end point was implant survival. Secondary end points included difference in ambulatory ability and mortality. Follow-up evaluations were performed at 2 months, at 1, 3 and 5 years. Implant and patient survival were followed until 2/2012. Survival analyses were performed using Kaplan-Meier curves with log-rank test. Data were analyzed using Chi-square test and Student's t test. RESULTS: Unipolar hemiarthroplasty group had a significantly higher dislocation rate when compared with bipolar hemiarthroplasty group. This did not translate into difference in revision rates at 8 years. Prosthetic survival ship was 0.98 (95% Cl 0.94-1.00) in the unipolar group and 0.97 (95% Cl 0.93-1.00) in the bipolar group. There were no statistically significant differences in ambulatory ability, possibility to return home mortality or early radiological acetabular erosion. There were significantly more one-time dislocations in the unipolar group, but there was no difference in incidence of revisions due to recurrent dislocations. The overall mortality rate was 6% at 30 days, 9% at 90 days, 16% at 12 months, and 53% at 5 years. There was no difference in mortality between the groups. CONCLUSIONS: Unipolar hemiarthroplasty group had a significantly higher dislocation rate when compared with bipolar hemiarthroplasty group. However, both provide elderly patients with equal ambulatory ability and low revision rate at medium-term follow-up.

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).

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.).

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.

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.