Hip Fracture in the ED Workup

Updated: Aug 12, 2021
  • Author: Moira Davenport, MD; Chief Editor: Trevor John Mills, MD, MPH  more...
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Workup

Imaging Studies

Anteroposterior (AP) and lateral views demonstrate most fractures. If a fracture is not obvious, look for alteration of the Shenton line and compare it to the other hip. In addition, check the neck-shaft angle, which is determined by measuring the angle created by lines drawn through the centers of the femoral shaft and femoral neck. This should be approximately 120-130°. For patients in whom femoral neck fracture is strongly suspected but standard radiographic findings are negative, an AP view with internal rotation provides a better view of the femoral neck.

If radiographic findings are equivocal but the history and physical examination are concerning for fracture, a CT scan should be considered, particularly in unstable patients or in those for whom MRI would be significantly delayed. A retrospective study questioned the sensitivity of plain radiography in detecting hip and pelvis fractures. [32]

A study of the use of digital tomosynthesis (DTS) as an adjunct to radiology for the workup of ED patients with suspected hip fractures reported DTS had a sensitivity of 82% and a specificity of 98%, compared to 47% sensitivity and 96% specificity for radiographs alone. [33]

If standard radiographic findings are negative and hip fracture is still  strongly suspected, MRI and bone scan have high sensitivity in identifying occult injuries. MRI is 100% sensitive in patients with equivocal radiographic findings. Traditionally, bone scan has been thought to be unreliable before 48-72 hours after fracture, but one study found a sensitivity of 93% regardless of time from injury, including fractures less than 24 hours old. For patients in whom a fracture is strongly suspected and radiographs are negative, consider admission if MRI or bone scan is not readily available.

According to the American College of Radiology (ACR) Appropriateness Criteria, radiography should always be the initial imaging modality. Then, depending on the clinical concern, additional studies can be obtained. MRI is recommended if the presence of a fracture is equivocal on radiographs. CT is the recommended alternative if MRI is contraindicated. [5]