Effects of joint effusion on quadriceps muscles in patients with knee osteoarthritis

40 female patients with knee osteoarthritis (OA) were randomized to receive either a joint saline injection group or a placebo group with the goal of determining the effects of knee joint effusion on quadriceps muscle strength. Quadriceps torque and root mean square values of the vastus medialis and vastus lateralis muscles were measured before and after the intervention. The results of this trial indicate that knee joint effusion had no effect on quadriceps muscle in this patient population.