What could cause pain in rib / left chest?

Costochondritis. Musculoskeletal injury or inflammation involving rib or muscle can cause pain. Anterior rib inflammation or costochondritis is viral. Bruises from physical activity can cause pain. Chest radiographs are usually negative. Inflammation of lining of lungs pleuritis mimics rib pain. Costochondritis usually subsides on own. Dx of costochondritis is by physical examination. See physician, .