Imaging Appearances of the Sternum and Sternoclavicular Joints

Carlos S. Restrepo, MD , Santiago Martinez, MD ,Diego F. Lemos, MD Lacey Washington, MD , H. Page McAdams, MD , Daniel Vargas, MD Julio A. Lemos, MD , Jorge A. Carrillo, MD , Lisa Diethelm, MD

The sternum and sternoclavicular joints—critical structures of the an­terior chest wall—may be affected by various anatomic anomalies and pathologic processes, some of which require treatment. Pectus excava-tum and pectus carinatum are common congenital anomalies that are usually benign but may warrant surgical treatment if they cause com­pression of vital internal structures. By contrast, developmental vari­ants such as the sternal foramen are asymptomatic and do not require further evaluation or treatment. Arthritides of the sternoclavicular joint (osteoarthritis, septic arthritis, and seronegative arthropathies) are common and must be differentiated before an appropriate man­agement method can be selected. The recognition of complications of sternotomy (eg, sternal dehiscence, secondary osteomyelitis) is critical to avoid life-threatening sequelae such as acute mediastinitis. Likewise, the detection of sternal fractures and sternoclavicular dislocations is important, especially where they impinge on vital structures. In addi­tion, sternal malignancies (most commonly, metastases and chondro­sarcoma) must be distinguished from benign neoplasms. To achieve accurate and timely diagnoses that facilitate appropriate treatment, radiologists must be familiar with the appearances of these normal anatomic variants and diseases of the sternum.