The advanced practice registered nurse (APRN) assesses the knee of a patient who presents with swelling of their right knee. The APRN places their thumb and index finger of their right hand on each side of the patella; with the left hand the APRN compresses the suprapatellar recess against the femur (as shown in the figure below). The APRN is able to palpate ejected fluid or "ballooning" of fluid. The APRN documents a positive "balloon sign", which is associated with: