Bone&JointAppraisal Vol 01 No 03 December 2016 COBLATION Chondroplasty Versus Mechanical Debridement: Randomized Controlled Trial with 10-Year Outcomes -Year Four-Year Ten-Year Group A COBLATION technology 30 pts 25 pts 13 pts Group B Mechanical debridement 30 pts 15 pts 9 pts In a retrospective study, chondral lesions were detected in 60% of 25,124 knee arthroscopies. 1 These lesions represent permanent damage that, unless properly treated, will progress in size and grade, as defined by the International Cartilage Repair Society (ICRS) classification system. 2 No clear consensus exists regarding the best treatment of ICRS grade III deep cartilage lesions. 3 Mechanical debridement (), or shaving, has disadvantages, including the inadvertent removal of adjacent healthy tissue and possible lesion progression caused by the shaver. 3,4 Radiofrequency (RF) chondroplasty is considered a promising treatment alternative to, 3 with pre-clinical research indicating it limits damage to the surrounding tissue and can create a smooth articular cartilage surface. 5 Managing temperature is important to achieve desired results while limiting damage to articular cartilage, as a sharp increase in chondrocyte damage occurs between 50 and 55 C. 6 A randomized trial compared clinical results after 50 C controlled bipolar RF chondroplasty via a chemical process () or with a shaver. Patients included in the study presented with knee pain associated with a medial meniscus tear and idiopathic ICRS grade III defect of the medial femoral condyle. Separately published one-, four- and 10- results 7 9 from this trial are discussed in detail in this Bone&Joint Appraisal. Conclusion Compared with conventional, COBLATION chondroplasty produced better clinical outcomes (as measured by Tegner score and Knee and Osteoarthritis Outcome Score [KOOS]) and a lower proportion of revisions due to persistent knee problems. Reduced patient numbers due to factors such as death or loss to follow up diminished the statistical power of the comparison at four and 10. However, 's advantages over extended up to a decade after treatment. Future research is needed to determine the optimal indications in which to perform COBLATION technology, as well as the long-term outcomes associated with its use. Page 1
-Year Arthroscopic knee chondroplasty using a bipolar radiofrequency-based device compared to mechanical shaver: results of a prospective, randomized, controlled study. Spahn G, Kahl E, Mückley T, Hofmann GO, Klinger HM. Knee Surg Sports Traumatol Arthrosc. 2008;16:565 573. Goal of To evaluate clinical outcomes after treating grade III weight-bearing chondral lesions using either classical mechanical shaver debridement (; Full radius resector, Arthrex, Naples, FL, USA) or bipolar radiofrequencybased chondroplasty (COBLATION technology; PARAGON T2 COBLATION wand, ArthroCare Corporation, Austin, TX, USA). Interventions Main study outcomes Key results Clinical study Level I 60 patients with knee pain associated with a medial meniscus tear and idiopathic ICRS grade III defect of the medial femoral condyle. During partial meniscectomy, patients randomized to either: (30 pts; mean age, 42.9 ; 43.3% male) (30 pts; mean age, 43.7 ; 50% male) Lost to follow-up 0 patients in either group Baseline characteristics No significant differences between groups Was study sufficiently designed to assess intervention? Clinical Outcomes KOOS assessment Tegner score Visual analogue scale (VAS) score Additional Outcomes NSAID use at one Safety Are study outcomes relevant and adequately measured? Six weeks Six weeks Baseline Preinjury Preoperative Six hours Twenty four hours Six weeks 10.8 10.3 35.9 29.3 81.2 57.3 0 20 40 60 80 100 Normalized KOOS score, mean Statistically significant superiority for for all five KOOS subscales at six weeks () and one () 0 1 2 3 4 5 6 Tegner activity score Significant differences () noted for both groups between pre-injury and one- scores 0 1 2 3 4 5 6 7 8 Pain scores Significantly fewer COBLATION patients (2% vs. 23%, p < 0.05) reported using NSAIDs for knee pain at one No complications or adverse events in either group Is sufficient information available to objectively assess results? Yes Yes Yes Conclusion To the authors knowledge, this was the first controlled study to compare clinical outcomes after both classical and bipolar for treating grade III defects of the medial femoral condyle. Results indicated that treating these lesions concomitantly with meniscectomy using rather than may provide better overall clinical results. -treated patients demonstrated earlier recovery from the arthroscopy than patients and had significantly improved clinical outcomes at both six weeks and one postoperatively. The appears to be an effective treatment for debriding chondral fibrillations and may even have the potential to stabilize the defect. Page 2
Four-Year Four- results from a randomized controlled study of knee chondroplasty with concomitant medial meniscectomy: mechanical debridement versus radiofrequency chondroplasty. Spahn G, Klinger HM, Mückley T, Hofmann GO. Arthroscopy. 2010;26(9 Suppl):S73-80. Goal of To test the hypothesis that bipolar COBLATION technology would produce a better clinical outcome than simple in the original cohort at an increased follow up of four. Interventions Main study outcomes Key results Clinical study Level I At four, 40/60 (66.6%) of original participants were available: (25 pts; mean age, 43.5 ; 44% male) (15 pts; mean age, 47.0 ; 40% male) Not included in follow-up analysis : 1 lost; 4 re-operated* : 1 died; 14 re-operated* *Only included in revision analysis, not clinical analysis Baseline characteristics No significant differences between remaining patients in groups Clinical Outcomes KOOS assessment Tegner score Additional Outcomes Revisions for persistent knee problems Four Preoperative Preinjury Baseline Four Revision arthroscopy 15.5 11.3 71.8 53.2 0 20 40 60 80 100 Normalized KOOS score, mean Statistically significant superiority for for all five KOOS subscales at four ( for four subscales, for one) 1.9 2.4 5.3 5.2 4.5 3.3 p=0.005 Tegner activity score At follow up, patients in the group had a significantly higher level of physical activity (P = 0.005) 2 Replacement 1 1 Replacement 4 8 14 2 Osteotomy Revision, by operation type Significantly higher proportion of revisions in group () Revision arthroscopy 4 Osteotomy Was study sufficiently designed to assess intervention? Are study outcomes relevant and adequately measured? Is sufficient information available to objectively assess results? Yes Yes Mostly (lost to follow up decreases comparative value) Conclusion This study reconfirmed the authors hypothesis that arthroscopic produces better clinical outcomes in the treatment of grade III articular cartilage lesions. Significantly fewer patients required revision operations within the observation interval. The study is limited by the number of patients lost to follow up in the group. Sample size calculations estimated that 25 patients were needed for each treatment, which was not achieved in the group. However, both groups remained comparable in baseline characteristics. Page 3
Ten-Year Mechanical debridement versus radiofrequency in knee chondroplasty with concomitant medial meniscectomy: 10- results from a randomized controlled study. Spahn G, Hofmann GO, von Engelhardt LV. Knee Surg Sports Traumatol Arthrosc. 2016;24:1560-1568. Goal of To test the hypothesis that COBLATION treatment produces better long-term clinical outcomes than. Interventions Main study outcomes Key results Clinical study Level I At 10, 22/60 (36.6%) of original participants were available: (13 pts; mean age, 44 ; 38.5% male) (9 pts; mean age, 47.2 ; 66.6% male) Not included in follow-up analysis : 9 lost; 1 died; 7 re-operated* : 1 lost; 2 died; 18 re-operated* *Only included in revision analysis, not clinical analysis Baseline characteristics No significant differences between remaining patients in groups Clinical Outcomes KOOS assessment Tegner score Additional Outcomes Revisions for persistent knee problems Four Ten Baseline Preinjury Preoperative Four Ten 9.1 17.8 33.1 50.8 56.9 56.4 72.8 81.6 0 20 40 60 80 100 Normalized KOOS score, mean Statistically significant superiority for for two of five KOOS subscales at 10 () 1 1 Tegner activity score, median Revision arthroscopy 3 3 7 Replacement 18 3 2 4 11 5 5 5 Revision arthroscopy 5 5 Osteotomy Revision, by operation type Rate of revision higher in than in RF (60% vs. 23.3%), but difference was Mean Kaplan-Meier survival time COBLATION technology 62.5 94.1 Was study sufficiently designed to assess intervention? Are study outcomes relevant and adequately measured? Mean time to revision, months Is sufficient information available to objectively assess results? Yes Yes Mostly (lost to follow up decreases comparative value) Conclusion This was the first long-term study in this field of investigation. It found that COBLATION treatment produced better clinical outcomes and lower revision rates than over long-term follow up. The mean time to revision was significantly longer after COBLATION treatment. The study is limited by the number of patients lost to follow up in the group. Sample size calculations estimated that 25 patients were needed for each treatment, which was attained in neither group at 10. However, both groups remained comparable in baseline characteristics. Page 4
Explaining Outcomes and Terms Explaining Outcomes Patient-reported outcome measurements Knee and Osteoarthritis Outcome Score (KOOS) Evaluates the short- and long-term consequences of knee injury and primary osteoarthritis. The KOOS scores use 42 items in five separately scored subscales: pain, symptoms, function in daily living, function in sport and recreation, and knee-related quality of life. The normalized KOOS score is graded from 0 (extreme symptoms) to 100 (no symptoms). 10 Tegner activity score Measures activity levels following knee ligament injuries. Graded from 0 (represents sick leave or disability pension due to knee problems) to 10 (participation in national and international elite sports). Patients provided pre-injury scores by estimating their physical activity level from memory, and pre-operative scores were provided after injury but before surgery. 11 Visual analogue scale (VAS) score Measures knee pain. Graded from 0 (no pain) to 10 (severe pain). 12 Additional outcomes Kaplan-Meier A measurement of the total percentage of prostheses that failed/required revision at a given time point. Terms Clinical study Any study in living human participants. Levels of Evidence Studies are categorized by the strength of analysis they provide, ranging from Level I (strongest) to Level V (weakest). Levels are defined as follows: Level I: Randomized, controlled trials or systematic reviews (combining results of from two or more published studies) of Level I studies. Level II: Randomized, controlled trials with notable flaws (e.g., no blinding); prospective comparative studies; and systematic reviews of Level II studies. Level III: Case-control studies (patients with one outcome [e.g., dislocation] compared against those without that outcome); retrospective comparative studies (patients receiving one treatment compared with those receiving another); and systematic reviews (combining results of from two or more published studies) of Level III studies. Level IV: Case series, in which patients are treated in one way without a comparison group treated another way. Level V: Includes expert opinions and case reports. P values The result of a test to determine if a conclusion or difference is significant. P values are expressed in thresholds of extremely significant (< 0.001), very significant (0.001 to 0.01), significant (0.01 to 0.05), and not significant ( 0.05). Statistical significance The likelihood that an outcome is attributable to a specific cause, rather than a random occurrence. Page 5
Abbreviations and Appraisal Criteria Abbreviations ICRS: International Cartilage Repair Society : mechanical debridement : non-significant NSAID: non-steroidal anti-inflammatory drug RF: radiofrequency Appraisal Criteria appraisal questions Was study sufficiently designed to assess intervention? Are study outcomes relevant and adequately measured? Is sufficient information available to objectively assess results? Level I-IV studies' appraisal criteria Research question or objective clearly stated Intervention(s) described in sufficient detail to recreate study design if necessary Comparison groups well balanced On-label usage is studied, or if not, this fact is explicitly acknowledged and controlled for If clinical, patients are representative of those who commonly receive device or treatment Includes commonly accepted outcomes for measuring safety and/or efficacy of chosen device or treatment Data collection methods clearly established Outcomes were measured using commonly accepted standards Includes a statistical analysis is adequately sized and powered to measure chosen endpoints Follow-up time is sufficient to measure association between an exposure and outcomes, if present Any design flaws identified are adequately controlled for All relevant study limitations are noted by the authors Each of the three main study questions is categorized as one of the following: Yes Mostly No If all their sub-criteria are met If a majority of sub-criteria are met (and the minority that are not met are considered relatively minor [e.g., research question is poorly defined]) If none or a majority of sub-criteria are not met (or when any sub-criteria not met are considered major [e.g., study is not well-balanced, lack of a statistical analysis]) Page 6
References 1. Widuchowski W, Widuchowski J, Trzaska T. Articular cartilage defects: study of 25,124 knee arthroscopies. Knee. 2007;14:177 182. 2. Kosy JD, Schranz PJ, Toms AD, Eyres KS, Mandalia VI. The use of radiofrequency energy for arthroscopic chondroplasty in the knee. Arthroscopy. 2011;27:695 703. 3. Horton D, Anderson S, Hope NG. A review of current concepts in radiofrequency chondroplasty. ANZ J Surg. 2014;84:412 416. 4. Spahn G, Fröber R, Linss W. Treatment of chondral defects by hydro jet. Results of a preliminary scanning electron microscopic evaluation. Arch Orthop Trauma Surg. 2006;126:223 227. 5. Amiel D, Ball ST, Tasto JP. Chondrocyte viability and metabolic activity after treatment of bovine articular cartilage with bipolar radiofrequency: an in vitro study. Arthroscopy. 2004;20:503 510. 6. Voss JR, Lu Y, Edwards RB, Bogdanske JJ, Markel. Effects of thermal energy on chondrocyte viability. Am J Vet Res. 2006;67:1708 1712. 7. Spahn G, Kahl E, Mückley T, Hofmann GO, Klinger HM. Arthroscopic knee chondroplasty using a bipolar radiofrequency-based device compared to mechanical shaver: results of a prospective, randomized, controlled study. Knee Surg Sports Traumatol Arthrosc. 2008;16:565 573. 8. Spahn G, Klinger HM, Mückley T, Hofmann GO. Four- results from a randomized controlled study of knee chondroplasty with concomitant medial meniscectomy: mechanical debridement versus radiofrequency chondroplasty. Arthroscopy. 2010;26(9 Suppl):S73 80. 9. Spahn G, Hofmann GO, von Engelhardt LV. Mechanical debridement versus radiofrequency in knee chondroplasty with concomitant medial meniscectomy: 10- results from a randomized controlled study. Knee Surg Sports Traumatol Arthrosc. 2016;24:1560 1568. 10. Roos EM, Lohmander LS. The knee injury and osteoarthritis outcome score (KOOS): from joint injury to osteoarthritis. Health Qual Life Outcomes. 2003;1:64. 11. Tegner Y, Lysholm J. Rating systems in the evaluation of knee ligament injuries. Clin Orthop Relat Res. 1985;(198):43 49. 12. Williamson A, Hoggart B. Pain: a review of three commonly used pain rating scales. J Clin Nurs. 2005;14:798 804. Page 7
The Bone&Joint literature series helps to support healthcare professionals in achieving better outcomes for patients, by enhancing understanding of techniques and our products. Lit no: PN 82550 Rev. A 12/16 Produced and published by the Scientific & Medical Affairs Department, Smith & Nephew Orthopaedics AG. Published December 2016 Copyright 2016 by Smith & Nephew Smith & Nephew Orthopaedics AG, Oberneuhofstrasse 10d, 6340 Baar, Switzerland Manufactured by: ArthroCare Corporation 7000 West William Cannon Drive Austin, TX 78735 USA Distributed by: Smith & Nephew, Inc. 150 Minuteman Road, Andover, MA 01810 USA Trademark of Smith & Nephew. All Trademarks acknowledged. Bone&JointAppraisal is available on Smith & Nephew s Education and Evidence website, www.smith-nephew.com/education