Three-dimensional computed tomography mapping of 136 tongue-type calcaneal fractures from a single centre

This study aimed to evaluate tongue-type calcaneal fractures using three-dimensional (3D) computed tomography (CT) mapping method.

A consecutive series of 136 tongue-type calcaneal fractures was used. CT data were used to reconstruct and reposition the 3D calcaneus body. E-3D Medical 18.01 software was used to superimpose the fractured calcaneal entity on the template, and the fracture line was drawn on the template. Finally, the heatmap was obtained using the fracture statistical analysis function. At the same time, the distribution of fracture lines in the anterior part of the calcaneus (APC) was recorded. Cases were divided into the following 3 subtypes according to the distribution of the tongue-type fracture lines of the calcaneal body: medial-lateral (Group A), upper-lateral (Group B), and upper-lateral-medial (Group C).

There were 68 cases in Group A, 48 cases in Group B, and 20 cases in Group C. Based on subtype, the characteristic fracture map of Groups A, B and C was constructed. The APC was evenly divided into zones A, B, and C from lateral to medial. In Group A, the most common types involve APC were Type AC (24, 35.3%) and Type A (11, 16.2%). In Group B, the most common types were Type AC (20, 41.7%), Type AB (8, 16.7%) and Type C (8, 16.7%). In Group C, the most common types were Type AC (8, 40.0%) and Type A (5, 25.0%).

This study investigates the distribution characteristics of fracture lines in subgroups of tongue-type calcaneal fractures for the first time. The results can help doctors improve their understanding of tongue-type calcaneal fractures, optimize internal fixation design, and provide a standard model for biomechanical experiments.