Abnormal rib morphology Chondritis inflammation of the costal cartilage, the cartilage that connects the ribs to the sternum (breastbone). 2025-12-17T15:52:15Z inflammation of the costal cartilage (the cartilage that connects the ribs to the sternum). The typical presentation of costochondritis is bilateral parasternal chest wall pain exacerbated by deep breaths, coughing, and stretching. The upper (predominantly second through fifth) costochondral and/or costosternal junctions are most commonly involved. The areas of tenderness are not generally accompanied by heat, erythema, or localized swelling.