Review Question - QID 210246

A 42-year-old male presents to clinic with 1 year of atraumatic left knee pain. He also reports subjective fever and chills. His physical examination is remarkable for diffuse knee pain but there is no overlying erythema or induration. His current laboratory values reveal a white blood cell count of 9200/µL (reference range [rr], 5000-12000/µL), absolute neutrophil count of 1800/µL (rr, 2000-7000/µL) with 53.7% lymphocytes (rr, 20-40%), an erythrocyte sedimentation rate (ESR) of 21 mm/h (rr, 0-20 mm/h), and a C-reactive protein (CRP) level of 2.2 mg/dL (rr, < 2 mg/dL). He has attempted a trial of physical therapy as well as a trial of oral antibiotics with no improvement of symptoms. Imaging is shown in Figures A-C. A biopsy is performed and is shown in Figure D. Which of the following is the best next step in management?