We present the case of a 57-year-old man who had suffered pain in the left hemithorax for a year, which started after a period of severe coughing during pneumonia. The pain was triggered by lying down. A computed tomography scan revealed two nonunion costal fractures. In the operating room, intercostal diastasis with pulmonary herniation was encountered in addition to the costal fractures. This report describes the technique used to reconstruct the thoracic wall with mesh and plate-osteosynthesis.