Moseley and colleagues tested whether arthroscopic débridement or arthroscopic lavage relieves knee osteoarthritis symptoms better than a placebo operation.
Single‑center, blinded, placebo‑controlled randomized trial of 180 patients with knee osteoarthritis at a Veterans Affairs hospital, followed 24 months (165 completed).
Methods
Design
Randomized placebo‑controlled trial
Patients and outcome assessors blinded
Setting
Single center
Houston VA Medical Center
Patients
180 randomized with knee osteoarthritis
165 completed the trial
Almost all men
Groups
Arthroscopic débridement (n = 59)
Arthroscopic lavage ≥ 10 L (n = 61)
Placebo: skin incisions and simulated débridement, no arthroscope (n = 60)
Follow-up
24 months
7 assessment points
Primary outcome
Knee‑Specific Pain Scale at 24 months
Key Findings
Neither lavage nor débridement gave better pain or function scores than placebo at any time point over 24 months.
Mean Knee‑Specific Pain Scale scores at 2 years were 51.6 with placebo, 53.7 with lavage and 51.4 with débridement (p = 0.64 and p = 0.96 vs placebo).
The 95% CIs excluded the minimal important difference in 72 of 84 group comparisons across time points, so a missed meaningful benefit is unlikely.
Débridement patients performed worse than placebo patients on timed walking and stair climbing at 2 weeks (56.0 vs 48.3, p = 0.02) and at 1 year (52.5 vs 45.6, p = 0.04).
Blinding held, with 13.8% of placebo patients guessing at 2 weeks that they had a sham procedure, vs 13.2% in the surgical groups.
Of 324 eligible patients, 144 (44%) declined to take part, which the authors note may have introduced selection bias.
Board pearl
The placebo arm had skin incisions and a mock débridement, but no arthroscope ever entered the knee.
Authors' conclusion
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.
Moseley and colleagues tested whether arthroscopic débridement or arthroscopic lavage relieves knee osteoarthritis symptoms better than a placebo operation.
Single‑center, blinded, placebo‑controlled randomized trial of 180 patients with knee osteoarthritis at a Veterans Affairs hospital, followed 24 months (165 completed).
Methods
Design
Randomized placebo‑controlled trial
Patients and outcome assessors blinded
Setting
Single center
Houston VA Medical Center
Patients
180 randomized with knee osteoarthritis
165 completed the trial
Almost all men
Groups
Arthroscopic débridement (n = 59)
Arthroscopic lavage ≥ 10 L (n = 61)
Placebo: skin incisions and simulated débridement, no arthroscope (n = 60)
Follow-up
24 months
7 assessment points
Primary outcome
Knee‑Specific Pain Scale at 24 months
Key Findings
Neither lavage nor débridement gave better pain or function scores than placebo at any time point over 24 months.
Mean Knee‑Specific Pain Scale scores at 2 years were 51.6 with placebo, 53.7 with lavage and 51.4 with débridement (p = 0.64 and p = 0.96 vs placebo).
The 95% CIs excluded the minimal important difference in 72 of 84 group comparisons across time points, so a missed meaningful benefit is unlikely.
Débridement patients performed worse than placebo patients on timed walking and stair climbing at 2 weeks (56.0 vs 48.3, p = 0.02) and at 1 year (52.5 vs 45.6, p = 0.04).
Blinding held, with 13.8% of placebo patients guessing at 2 weeks that they had a sham procedure, vs 13.2% in the surgical groups.
Of 324 eligible patients, 144 (44%) declined to take part, which the authors note may have introduced selection bias.
Board pearl
The placebo arm had skin incisions and a mock débridement, but no arthroscope ever entered the knee.
Authors' conclusion
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.