Assertion: sacrum | /r/HasProperty | obscured on view
Facets:
value: by overlying pelvic structures
type: MANNER
Source sentences:
text: Radiography did not show the fractures in 22 of 23 patients, even in retrospect, possibly because these radiographs were long cassette images of the entire spine rather than focused examinations of the lumbar spine and because the sacrum was obscured on both views by overlying pelvic structures or bowel gas.