Review Question - QID 210750

A 55-year-old man presents to his primary care physician for knee pain. The patient has had left knee pain, which has been steadily worsening for the past year. He states that ice and rest have led to a minor improvement in his symptoms. He recently bumped his knee; however, he says that it has not altered his baseline pain when ambulating. The patient is a butcher and lives with his wife. His current medications include insulin, metformin, hydrochlorothiazide, and lisinopril. He is attending Alcoholics Anonymous with little success. His temperature is 98.7°F (37°C), blood pressure is 137/88 mmHg, pulse is 65/min, respirations are 11/min, and oxygen saturation is 98% on room air. A physical exam reveals a left knee that is mildly erythematous with some bruising. There is no pain upon palpation of the joint or with passive range of motion. The patient exhibits a mildly antalgic gait. Which of the following is the most appropriate initial step in management?