In people who received the sham treatment, we placed a 16-gauge catheter in the lateral suprapatellar position just to the knee joint capsule and infused small volumes (less than 5 ml per "exchange" x 20) of saline into the subcutaneous tissue while manipulating the anterior knee to mimic efforts to shift fluid within the knee during the "aspiration" phase of each exchange. Patients could see the supply bag of sterile saline but could not see the waste bag of this closed drainage system.