Study Of Calcaneal Fracture Ma

Objectives : Calcaneal fractures are the most common tarsal fractures,accounting for 1% to 4% of all fractures in adults.Most(60%-80%)calcaneal fractures are intra-articular fractures.Displaced intra-articular fractures of the calcaneus have complex structures,and precise reduction and internal fixation are the most effective means to reduce the disability rate.Fracture Mapping technology provides a more comprehensive,three-dimensional and intuitive understanding of the specific shape of a certain fracture by the form of "big data",providing more comprehensive information and more intuitive guidance for clinical practice.The purpose of this study is to use CT data of calcaneal fractures,use 3D reconstruction technology and Fracture Mapping technology to describe the distribution characteristics of fracture lines,so as to improve physicians’ understanding of such fractures,provide standardized fracture model and guide internal fixation strategies.Methods: A total of 197 cases of Sander type 2 intra-articular compression calcaneal fractures,136 cases of tongue-type intra-articular calcaneal fractures and 68 cases of extra-articular calcaneal fractures were collected.The 3D models of the calcaneus and each fracture fragment were extracted in Mimics Research 20.0(Materialise,Leuven,Belgium)software.The 3D model was imported into 3-matic Research 12.0(Materialise,Leuven,Belgium)software,and the fracture fragments were reduced by rotation and translation.Finally,the3 D model was imported into E-3D medical x64 18.01(Central South University,Changsha,China)software,and the 3D model was rotated and moved to coincide with the standard model.After registration,the calcaneal fracture lines were drawn on the 3D calcaneal model,and then the fracture analysis function was used to convert the calcaneal fracture line into heatmap.The fracture line distribution and heat map were then observed from multiple perspectives.The Anterior Part Of the Calcaneus(APC)was divided into A,B,and C zones from the lateral to the medial,The middle subtalar articular surface was considered as the D zone.The frequency of each fracture in APC was recorded.Results: In intra-articular compression calcaneal fractures,there were 109 cases belonged to Sanders type 2A,46 cases to Sanders type 2B,and 24 cases to Sanders type 2C.Based on the data,we have drawn the characteristic fracture map.This study found that the most common types of sanders 2A in APC and middle talar articular surface are Type AC and Type AD.In sanders 2B,the most common type is Type AC and in sanders 2C is Type ACD.Cases of tongue-type intra-articular calcaneal fractures 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).Based on the data,we have drawn the characteristic fracture map.This study found that the most common types of tongue-type calcaneal fractures in APC and middle talar articular surface are Type AC,but there are differences between Group A,B and C.There were 11 cases of Extra-articular calcaneal body compression fractures,45 cases of body split fractures,2 cases of anterior tubercle fractures,and 10 cases of posterior tuberosity fractures.Based on the data,we have drawn the characteristic fracture map.The median Boler angle of calcaneal body extra-articular compression fractures was 20.63,and the median Bohler angle of calcaneal body extra-articular split fractures was 12.20.Mann-Whitney U test was performed for two groups,and there was a significant difference in Bohler angle(p=0.009).Conclusions: This study constructed Sander2 intra-articular compression calcaneal fracture,tongue-type intra-articular calcaneal fracture and extra-articular calcaneal fracture map.This study can improve physicians’ understanding of calcaneal fractures,provide standardized fracture models and guide fracture internal fixation strategies.