## 4 Discussion
Impactor tip diameters of 1.2 mm and 1.6 mm with high impact loading resulted in the highest stresses and strains on the ipsilateral side. Thus, impactor tip diameters between 1.2 mm and 1.6 mm would be convenient to use in the rat hemicontusion SCI models for the cervical region without damaging the contralateral side of the spinal cord. Our study provides an insight into hemicontusion SCI models in the rat. Conceptualization, B.K., K.K. and Y.H.K. ; methodology, B.K., K.K. and Y.H.K. ; software, B.K. ; validation, B.K., K.K., T.B. and Y.H.K. ; formal analysis, B.K., K.K. and Y.H.K. ; investigation, B.K., K.K. and Y.H.K. ; resources, Y.H.K. ; data curation, B.K. and K.K. ; writing--original draft preparation, B.K. and K.K. ; writing--review and editing, B.K., K.K., T.B. and Y.H.K. ; visualization, B.K. ; supervision, Y.H.K. ; project administration, K.K. and Y.H.K. ; funding acquisition, K.K. and Y.H.K. All authors have read and agreed to the published version of the manuscript. This work was supported by a grant from Kyung Hee University in 2018 (KHU-20181173). The authors declare no conflict of interest. References  
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