Companion shadow

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AP radiograph demonstrating companion shadow of the clavicle AP radiograph demonstrating companion shadow of the clavicle.jpg
AP radiograph demonstrating companion shadow of the clavicle
A rib companion shadow (indicated by two arrows) RibCompanionShadow.gif
A rib companion shadow (indicated by two arrows)

Companion shadow is a term used in describing radiographs that denotes the appearance of a smooth, homogenous, radiodensity with a well-defined margin that runs parallel with a bony landmark. Companion shadows represent soft tissue that overlies the respective bony landmark in profile. They are not seen in every radiograph and can be misinterpreted as pathology.

Types of companion shadow

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<span class="mw-page-title-main">Shoulder</span> Part of the body

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