A controlled trial of arthroscopic surgery for osteoarthritis of the knee. A randomized, controlled trial of arthroscopic surgery versus closed-needle joint lavage for patients with osteoarthritis of the knee. Articular debridement versus washout for degeneration of the medial femoral condyle. A five-year study.
Many patients report symptomatic relief after undergoing arthroscopy of the knee for osteoarthritis, but it is unclear how the procedure achieves this result. We conducted a randomized, placebo-controlled trial to evaluate the efficacy of arthroscopy for osteoarthritis of the knee.
                A total of 180 patients with osteoarthritis of the knee were randomly assigned to receive arthroscopic débridement, arthroscopic lavage, or placebo surgery. Patients in the placebo group received skin incisions and underwent a simulated débridement without insertion of the arthroscope. Patients and assessors of outcome were blinded to the treatment-group assignment. Outcomes were assessed at multiple points over a 24-month period with the use of five self-reported scores--three on scales for pain and two on scales for function--and one objective test of walking and stair climbing. A total of 165 patients completed the trial.
                At no point did either of the intervention groups report less pain or better function than the placebo group. For example, mean (+/-SD) scores on the Knee-Specific Pain Scale (range, 0 to 100, with higher scores indicating more severe pain) were similar in the placebo, lavage, and débridement groups: 48.9+/-21.9, 54.8+/-19.8, and 51.7+/-22.4, respectively, at one year (P=0.14 for the comparison between placebo and lavage; P=0.51 for the comparison between placebo and débridement) and 51.6+/-23.7, 53.7+/-23.7, and 51.4+/-23.2, respectively, at two years (P=0.64 and P=0.96, respectively). Furthermore, the 95 percent confidence intervals for the differences between the placebo group and the intervention groups exclude any clinically meaningful difference.
                In this controlled trial involving patients with osteoarthritis of the knee, the outcomes after arthroscopic lavage or arthroscopic débridement were no better than those after a placebo procedure. To compare arthroscopic surgery and closed-needle joint lavage for patients with non-end-stage osteoarthritis (OA) of the knee under controlled, experimental conditions.
                Thirty-two subjects who met specific clinical, radiologic, medical, and rehabilitation criteria were randomized to receive arthroscopic surgery (n = 18) or joint lavage (n = 14). Outcome measures evaluated at baseline and at 3 and 12 months of followup included 3 standard clinical parameters, self-reported pain and functional status (by the Arthritis Impact Measurement Scales), 50-foot walk time, 2 global scales, and direct and indirect medical costs.
                At 3 months of followup, there were no significant between-group differences in pain, self-reported and observed functional status, and patient and "blinded" physician global assessments. The arthroscopic procedure cost $3,840 more than did closed-needle joint lavage. After 1 year, there were no between-group differences in medication costs, utilization of medical services, or indirect costs related to employment or use of household help. After 1 year, 44% of subjects who underwent arthroscopy reported improvement and 58% of subjects who underwent joint lavage improved. Patients with tears of the anterior two-thirds of the medial meniscus or any lateral meniscus tear had a higher probability of improvement (by "blinded" physician assessment) after arthroscopic surgery (0.63) than did patients with other intraarticular pathology (0.20).
                The search for and removal of soft tissue abnormalities via arthroscopic surgery does not appear justified for all patients with non-end-stage OA of the knee who fail to respond to conservative therapy, but it may be beneficial for certain subgroups. In a prospective randomised trial 76 knees with isolated degenerative changes in the medial femoral condyle of grades 3 or 4 were treated by either arthroscopic debridement (40) or washout (36). All knees were followed up for at least one year and 58 for five years. The mean follow-up time was 4.5 years in the debridement group and 4.3 years in the washout group. At one year 32 of the debridement group and five of the washout group were painfree and at five years 19 of a total of 32 survivors in the debridement group and three of the 26 in the washout group were also free from pain. The mean improvement in a modified Lysholm score was 28 for the debridement group at one year and 21 at five years. In the washout group it was only 5 at one year and 4 at five years. For knees with lesions of the medial femoral condyle of grades 3 or 4, arthroscopic debridement appears to be the treatment of choice with over half the patients free from pain after five years.
There is 'gold' level evidence that AD has no benefit for undiscriminated OA (mechanical or inflammatory causes).