Tidal irrigation as treatment for knee osteoarthritis: a sham-controlled, randomized, double-blinded evaluation. Saline washout for knee osteoarthritis: results of a controlled study. A controlled trial of arthroscopic surgery for osteoarthritis of the knee. Effects of joint lavage and steroid injection in patients with osteoarthritis of the knee: results of a multicenter, randomized, controlled trial. Tidal irrigation versus conservative medical management in patients with osteoarthritis of the knee: a prospective randomized study. Tidal Irrigation Cooperating Group. Arthroscopic treatment of osteoarthritis of the knee: a prospective, randomized, placebo-controlled trial. Results of a pilot study. Visually-guided irrigation in patients with early knee osteoarthritis: a multicenter randomized, controlled trial.
To evaluate the effectiveness of tidal irrigation (TI) in comparison with a well-matched sham irrigation (SI) procedure as a treatment for knee osteoarthritis (OA).
                One hundred eighty subjects with knee OA were randomized to receive TI or SI, with clinical followup over the ensuing 12 months. The primary outcomes of interest were change in pain and function, as measured by the Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC). Subjects and the nurse assessor were blinded, and success of blinding was assessed.
                Although the study groups were otherwise comparable, the baseline WOMAC pain and physical functioning scores were higher (worse) in the SI group. After adjustment for baseline, there were no differences between the effects of Twenty patients with persistent symptoms due to osteoarthritis of the knee were randomly allocated to a saline washout or control group. Both groups showed improvement. Knee washout conferred no more benefit than intra-articular saline injection. 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 evaluate the efficacy of joint lavage and intraarticular steroid injection, alone and in combination, in the treatment of patients with symptomatic knee osteoarthritis (OA).
                Ninety-eight patients with painful tibiofemoral OA were enrolled in a prospective, randomized, controlled, 2 x 2 factorial-design trial of 6 months' duration. The 4 treatment groups consisted of 1) intraarticular placebo (1.5 ml of 0.9% normal saline), 2) intraarticular corticosteroids (3.75 mg of cortivazol in 1.5 ml), 3) joint lavage and intraarticular placebo, and 4) joint lavage and intraarticular corticosteroid. Outcome measures evaluated at baseline, week 1, week 4, week 12, and week 24 included severity of pain (100-mm visual analog scale [VAS]), global status (100-mm VAS), and Lequesne's functional index.
                No interaction between steroid injection and joint lavage was demonstrated. Patients who had undergone joint lavage had significantly improved pain VAS scores at week 24 (P = 0.020). In contrast, corticosteroid injection had no long-term effect (P = 0.313); corticosteroid injection was associated with a decrease in pain only at week 1 (P = 0.003) and week 4 (P = 0.020). After week 4, Lequesne's functional index was not significantly improved regardless of the assigned treatment.
                Compared with placebo, both treatments significantly relieved pain but did not improve functional impairment. The effects of the 2 treatments were additive. Cortivazol provided short-term relief of pain (up to week 4). The effects of joint lavage persisted up to week 24. To determine the efficacy of tidal knee irrigation for knee pain due to osteoarthritis (OA), we conducted a randomized, single blind, 14-week prospective trial comparing medical management with tidal knee irrigation in 77 patients with non-end stage OA of the knee and unilateral pain refractory to standard medical treatment. Fifty-seven patients completed the study. Statistically significant differences (p less than 0.05) favoring tidal knee irrigation over medical management were pain after 50' walk, pain after 4-stair climb, most intense pain in previous day, frequency of knee stiffness with inactivity, days of morning knee stiffness in previous week, physician assessment of knee tenderness and overall assessments of therapy effectiveness by both patient and physician. Tidal knee irrigation results in more favorable improvement of pain due to OA than can be accomplished with traditional medical management. The reasons why many patients seemingly benefit from arthroscopic treatment of osteoarthritis of the knee remain obscure. The purpose of this pilot study was to determine if a placebo effect might play a role in arthroscopic treatment of this condition. After giving full informed consent, including full knowledge of the possibility and nature of a placebo surgery, five subjects were randomized to a placebo arthroscopy group, three subjects were randomized to an arthroscopic lavage group, and two subjects were randomized to a standard arthroscopic debridement group. The physicians performing the postoperative assessment and the patients remained blinded as to treatment. Patients who received the placebo surgery reported decreased frequency, intensity, and duration of knee pain. They also thought that the procedure was worthwhile and would recommend it to family and friends. Thus, there may be a significant placebo effect for arthroscopic treatment of osteoarthritis of the knee. The small numbers in this preliminary study preclude a valid statistical analysis, and no conclusions can be drawn regarding the superiority of one treatment over another. A larger study is needed to evaluate fully the efficacy of an arthroscopic procedure for this condition and to decide if it is reasonable to expend health care resources for this treatment; the larger study should include a placebo control group. To determine if visually-guided arthroscopic irrigation is an effective therapeutic intervention in patients with early knee osteoarthritis.
                Ninety patients with knee osteoarthritis were randomized in a double-blind fashion to receive either arthroscopic irrigation with 3000 ml of saline (treatment group) or the minimal amount of irrigation (250 ml) required to perform arthroscopy (placebo group). The primary outcome variable was aggregate WOMAC score.
                The study did not demonstrate an effect of irrigation on arthritis severity as measured by aggregate WOMAC scores, the primary outcome variable; the mean change in aggregate WOMAC score at 12 months was 15.5 (95% CI 7.7, 23.4) for the full irrigation group compared to 8.9 (95% CI 4.9, 13.0) for the minimal irrigation group (P=0.10). Full irrigation did have a statistically significant effect on patients' self-reported pain as measured by the WOMAC pain subscale and by a visual analog scale (VAS) (the secondary outcome variables). Mean change in WOMAC pain scores decreased by 4.2 (95% CI -0.9, 9.4) for the full irrigation group compared with a mean decrease of 2.3 (95% CI -0.1, 4.7) in the minimal irrigation group (P=0.04). Mean VAS pain scores decreased by 1.47 (95% CI -1.2, 4.1) in the full irrigation group compared to a mean decrease of 0.12 (95% CI 0.0, 0.3) in the minimal irrigation group (P=0.02). A hypothesis-generating post-hoc analysis of the effect of positively birefrigent intraarticular crystals showed that patients with and without intraarticular crystals had statistically significant improvements in pain assessments and aggregate WOMAC scores at 12 months; patients with crystals had statistically greater improvements in pain.
                Visually-guided arthroscopic irrigation may be a useful therapeutic option for relief of pain in a subset of patients with knee OA, particularly in those who have occult intraarticular crystals.
                Copyright 2000 OsteoArthritis Research Society International.
Joint lavage does not result in a relevant benefit for patients with knee osteoarthritis in terms of pain relief or improvement of function.