My Husband Had A Very Painful Knee 2-3 Weeks Ago.

My husband had a very painful knee 2-3 weeks ago. Approximately 10 days ago it flared into swelling, heat, redness down the front of the shin from the knee to just above the ankle, joint stiffness, severe tenderness of the tibia and fibula and a burning sensation when he walked. Our doctor suggested it was an infection of some sort and put him on antibiotics and 5 days of elevation and rest. This he did and completed two courses of antibiotics. The heat, redness and burning sensation have subsided however the bone tenderness, swelling, bone tenderness and knee stiffness remain. What could this be and what should we ask our doctor to do?