Reliability of bone scintigraphy for suspected scaphoid fractures.

Purpose: To examine the observer variation for bone scintigraphy in the detection of occult scaphoid fractures in daily practice, using only the early bone scanning images.
Methods: One hundred bone scans of patients with a suspected scaphoid fracture but negative initial radiographs were prospectively included to calculate the inter- and intraobserver variation. Three nuclear medicine physicians independently evaluated all bone scans at 2 different points in time with a 3-month interval. The observers filled out a blinded scoring sheet for each patient. They scored if a scaphoid fracture was present or not. In addition, they scored the presence or absence of another fracture. The inter- and intraobserver variation was analyzed using the kappa statistic.
Results: The interobserver variation showed substantial agreement for a scaphoid fracture and almost perfect agreement for another fracture. The intraobserver variation showed almost perfect agreement for both a scaphoid fracture and another fracture.
Conclusions: In the present study, early static images of bone scintigraphy for suspected scaphoid fractures showed very little inter- and intraobserver variation. In addition, expertise does not seem to have a negative influence on the results. This enhances the possibility of using bone scintigraphy in daily practice.