First and second rib fractures occurred in 11 (16%) of 69 patients undergoing median sternotomy. Although 6 patients had no symptoms related to the rib fractures, 5 patients had postoperative chest, shoulder, and arm pain suggestive of angina pectoris or postpericardiotomy syndrome. The correct diagnosis of pain related to postoperative upper rib fracture may be made by direct visualization of the fracture on supine anteroposterior radiographs, elicitation of pain by palpation of the rib or motion of the upper extremity, lack of response to nitroglycerin, and negative electrocardiogram and cardiac enzyme levels. Upper rib fractures following median sternotomy are usually radiographically detectable within the first three postoperative days. Placement of the Ankeney sternal retractor with the upper blade in a lower position (fourth intercostal space) may reduce the incidence of this postoperative complication.