Objectives: The aim of this study was to determine the correlation of the intra-operative fluoroscopic 2D- and 3D-images compared with a postoperative CT-scan, in terms of quality of reduction and fixation of calcaneal fractures. Methods: Patients requiring open reduction and internal fixation (ORIF) of a calcaneal fracture were recruited as part of the EF3X-trial. During surgery, intra-operative images of fluoroscopic 2D- and 3D-imaging were obtained to assess the quality of the reduction and implant position. All patients received a postoperative CT-scan within one week. The operating surgeon evaluated intra-operatively both 2D- and 3D-images according to a 23-item scoring protocol on a 3-point Likert scale. A scoring panel, consisting of three clinical experts, evaluated all images in a blinded and independent fashion. Intraclass correlation coefficients (ICC) with their 95% confidence intervals (CI) were calculated using a two-way-random model with absolute agreement. Results: A total of 102 calcaneal fractures were included. Agreement of 3D-imaging for the quality of reduction was better than 2D-imaging, although still fair, but for fixation moderate to good. Agreement between the 2D-images and the CT-scans was poor to fair. Intra-operative 2D-imaging received the highest ratings for image quality and interpretability, followed by CT-scanning. Conclusion: Implant position can be evaluated satisfactory with the aid of intra-operative 3D imaging. Although intra-operative 3D imaging had a better agreement with postoperative CT-scanning than 2D-imaging, there is a need to improve image quality and suppress scattering from implants to improve the additional value of intra-operative 3D imaging in calcaneal fracture reduction and fixation.
Beerekamp, M. S. H., de Muinck Keizer, R. J. O., Schepers, T., Beenen, L. F. M., Luitse, J. S. K., Schep, N. W., ... on behalf of the EF3X-studygroup (2019). The correlation between intra-operative 2D- and 3D fluoroscopy with postoperative CT-scans in the treatment of calcaneal fractures. European Journal of Radiology, 112, 222-228. https://doi.org/10.1016/j.ejrad.2019.01.013