The sensitivity of ct scans in diagnosing occult femoral neck fractures.

Non-displaced hip fractures can be difficult to diagnose on plain film radiographs. When there is ongoing clinical suspicion of an occult fracture, further imaging is obtained. We investigated the sensitivity of computed tomography (CT) scans in detecting these fractures and the delays to surgery that three-dimensional imaging causes. We identified 78 CT scans performed for possible hip fractures over the past 3 years with the presence and absence of a fracture recorded. Based on subsequent imaging, the accuracy of CT scans was determined. CT scanning yielded sensitivity was 86% and specificity 98% for occult hip fracture (OHF). The median delay to definitive diagnosis was 37h. Our results demonstrate that CT scan does not bear sufficient sensitivity to detect all OHFs. We therefore recommend that MRI should be offered when a fracture is suspected. CT scans should be reserved for when MRI is not available, but a negative scan should be confirmed with subsequent MRI.