How reliable are CT scans for the evaluation of calcaneal fractures?

CT scans are deemed to be the gold standard for the evaluation of calcaneal fractures. However, the reliability of the interpretation has not been studied systematically.

In a prospective multicenter study, the CT data set of five different fractures was presented to 57 evaluators. The participating surgeons were asked to assess calcaneal fractures on the basis of a multiple choice questionnaire. The CT scans were validated by the intraoperative findings. The questionnaires were compared to the model solution of three foot and ankle surgeons. The intra- and interrater reliability was calculated.

The proportion of intraobserver agreement was 82%. Cohen's kappa was κ = 0.748 with P < 0.0001. In total, 61% of the items were answered similarly to the model answer. Only 27% of the evaluators were able to correctly classify the fracture according to Sanders and 63% of the evaluators agreed that surgical procedure was necessary. The more experienced the surgeon, the higher was the interrater agreement.

This is the first study to systematically analyze the reliability of the interpretation of CT scans of calcaneal fractures. This was found to be unsatisfactory. Future studies must show, if specific interventions, e.g., teaching programs or image procession modalities (e.g., 3D reconstructions), are capable of improving the quality of interpretation of CT scans for calcaneal fractures.