Companion shadows

Dr Henry Knipe and Dr M Venkatesh et al.

Companion shadows are smooth, homogeneous, radiopaque shadows running parallel along the bones. In a study of 700 chest radiographs, Ben Felson found that 75% had companion shadows on the lower ribs 3.

Radiographic features

They appear secondary to soft tissues and intercostal muscles running along:

Practical points

Companion shadows need to be differentiated from periosteal reactions secondary to adjacent bony or soft tissue pathology.

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Article information

rID: 25550
Section: Gamuts
Synonyms or Alternate Spellings:
  • Companion shadow

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Cases and figures

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    Case 1: right scapula
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