episternal ossicles

Episternal (or suprasternal) ossicles are accessory bones and a normal variant of the sternum. They result from supernumerary ossification centers and are seen in ~4% (range 1-7%) of the population.

Gross anatomy

Episternal ossicles are usually located posterior or superior to the superior border of the manubrium and may be unilateral or bilateral. They range in diameter from 2-15 mm and are located in a retro- or supra-manubrial location.

In three dimensions, they are quadrilateral pyramids whose bases articulate with the manubrium. The apices point medially, but rounding of the corners may mask this appearance.

Radiographic features

Their visualization using radiographs can be difficult but with the use of computed tomography are clearly identifiable, revealing unilateral or bilateral triangular ossicles in a retro- or supra-manubrial location.

Differential diagnosis

• parasternal ossicles: within the 1 costal cartilage

It is also important to differentiate them from:

• calcified lymph nodes
• fracture fragments
• vascular calcifications
• foreign bodies
• osteophytes

Siehe auch:

• Anomalien des Sternums
• Akzessorischer Knochen
• Manubrium sterni
• nicht fusionierte Sternumsegmente
• Sternum bifidum

und weiter:

• Fissura sterni congenita