hest Wall (Including the Scapula and Clavicle): The Sternum

10.1055/b-0034-87919

Chest Wall (Including the Scapula and Clavicle): The Sternum

**Table 5.1 Sternum: congenital, genetic, and syndromic diseases that may alter the sternum**
Diagnosis	Findings	Comments
Variations in normal anatomy	Sternal foramen, sclerotic bands, manubriosternal, and sternoxiphoidal fusions.	Cortical irregularity, expansion, and soft-tissue mass help distinguish a pathologic process from normal variations in anatomy.
Pectus excavatum	Concave posterior depression of the sternum often with rotation along the transverse plane results in a reduction of the prevertebral space, leftward displacement and axial rotation of the heart, and reduction in the space occupied by the lungs (usually the left lung).	Most common congenital deformity of the sternum. The pectus (Haller) index, derived by dividing the transverse diameter of the chest by the anteroposterior (AP) diameter, obtained on axial computed tomography (CT) or magnetic resonance imaging (MRI). A pectus index greater than 3.25 necessitates surgical correction.
Trisomy 21	Multiple manubrial ossification centers (hypersegmentation).	Probability of trisomy 21 increases with the number of anomalies present on the chest radiograph (11 rib pairs and a bell-shaped chest).
Sickle cell Fig. 5.1	Sternal cupping at the ends of the segments.	Similar appearance as end plate depressions in vertebral bodies. May be seen in up to 8% of patients.
Turner syndrome	Short, premature fusion of manubriosternal junction or mesosternum, decreased ratio of sternal body to manubrium, two ossification centers, bowing, mild pectus excavatum.	(see Table 5.30 )
Poland syndrome	Deformity of the sternum associated with absence of muscles and clavicle.	(see Table 5.15 )
Chronic recurrent multifocal osteomyelitis (CRMO)	Hyperostosis and osteomyelitis.	Chronic inflammatory condition of unknown etiology. Usually multifocal. Children 5–15 y old. Accompanied by synovitis, acne, pustulosis. Adult form is SAPHO (s ynovitis, a cne, p ustulosis, h yperostosis, and o steitis).

**Fig. 5.1 Sickle cell disease** with sternal infarcts at the ends of the ossification centers (arrow shows an example of one area of involvement).

**Table 5.2 Sternum: masses**
Diagnosis	Findings	Comments
Pectus carinatum	Anterior displacement of sternum.	May be confused with malignancy on physical examination. Also known as pigeon breast and is less common (1:1500 births) than pectus excavatum.
Malignant	(see Table 5.74 )	Rare. Chondrosarcoma, lymphoma, Ewing sarcoma, osteosarcoma.
Benign		Rare. Enchondroma, osteochondroma, hemangioma, hemangiopericytoma, osteoid osteoma, osteoblastoma, fibrous dysplasia, Langerhans cell histiocytosis, brown tumor.