Jay-Jung Kim

A Study on Reuse 3D MCAD Data for BIM based Library Creation - Focusing on the Mechanical BIM Library -

Recent AEC industry, is introducing BIM based design process which mainly focuses on collaboration and integration. Since BIM has characteristic of utilizing several design libraries in various fields across the AEC industry, obtaining BIM libraries are essential for introducing and applying the BIM successfully. Thus, creating BIM libraries and guidelines for various fields are needed. BIM libraries can be categorized into disciplines such as architectural, structural, mechanical and electrical industries. Especially, companies in mechanical industry possesses design data for creating BIM library. Due to the fact, we standardized the property information for BIM libraries. And for BIM library production, we have developed a program which uses neutral format to convert 3D MCAD data designed by NX into Revit Family. Finally, we developed a program that merges property information to Revit Family file.

Analytical Osteotomy Model for Three-dimensional Surgical Planning of Opening Wedge High Tibial Osteotomy

Opening wedge high tibial osteotomy (OWHTO) is widely used to treat unicompartmental osteoarthritis of the knee caused by degenerative deformations of the anatomical axes of the leg. However, since it is difficult to accurately plan the surgical adjustment degrees such as coronal correction angle and tibial posterior slope angle in order to align the axes before the actual procedure, a number of studies have proposed analytical models to solve this problem. While previous analytical models for OWHTO were limited to specific tibial configurations, this study proposes a Generic analytical osteotomy model (GAOM) and a surgical planning system that are applicable for general tibial morphologies and tibia conditions. The validity and generality of the model were verified in a total of 60 OWHTO cases. Results showed that the tibial shape and the slope of the cut plane significantly affect the adjustment degrees. Comparison between the required degrees and the ones estimated from GAOM resulted in the mean error of 0.12°. The surgical planning system, based on GAOM, allows the operating surgeon to easily calculate surgical parameters needed to treat a patient.

Effect of Anteromedial Cortex Oblique Angle on Change of Tibial Posterior Slope Angle in High Tibial Osteotomy Using Computer Assisted Surgery (CAS)

The leading surgical method for correcting the misalignment of the varus and valgus in the knee joint is the high tibial osteotomy (HTO). In the opening wedge HTO (OWHTO), there is no concern about damaging the peroneal nerve on the lateral tibia of the proximal fibula. OWHTO has been the preferred choice, as the opening of the correction angle can be modulated during the operation. The correction of the varus and valgus on the coronal plane are performed adroitly. Nevertheless, there have been numerous reports of unintended changes in the medial tibial plateau and posterior slope angle (PSA). The authors have developed an HTO method using computer-assisted surgery with the aim of addressing the abovementioned problems from an engineers perspective. CT images of the high tibia were reconstructed three-dimensionally, and a virtual osteotomy was performed on a computer. In addition, this study recommends a surgical method that does not cause changes in the PSA after OWHTO. The results of the study are expected to suggest a clear relationship between the anteromedial cortex oblique angle of each patient and the PSA, and an optimal PSA selection method for individuals.