The planning of endoprosthesis implantation in using of modern

The planning of endoprosthesis implantation in using of modern technique
of modeling
P.Borkowski1, K.Skalski2, W.Woźniak3
1
2
3
Bialystok University of Technology, Faculty of Mechanical Engineering, Department of Materials and
Biomedical Engineering; Poland, 15-351 Bialystok, ul.Wiejska 45a; [email protected]
Warsaw University of Technology, Faculty of Production Engineering, Department of Machine Designed
and Biomedical Engineering; Poland, 02-524 Warsaw, ul.Narbutta 85
Institute of Mother and Child in Warsaw, Oncological Surgery Clinic of Children and Youth Poland, 01-211
Warszawa, Kasprzaka 17a
1. Introduction
Preoperating planning is a basic procedure that precedes a surgical operation. The part of that proceeding are
anamnesis and X-ray examination, completed by CT (Computer Tomography) and MRI (Magnetic Resonance
Imaging) examination, that allow better diagnosis[1,2]. In this way the reconstruction of patient’s skeletal system
and choice of endoprosthesis is performed. The size of every element is selected by using X-ray pictures and
contour master delivered by the implant producer. This procedure can be completed by using engineering
technique in modelling and reconstruction of pathologically changed bone tissue and by performing virtual
simulation of surgical treatment in a computer system. It allows a surgeon to precisely prepare the operation[3,4].
In the paper procedure of choice and valuation of knee tumour endoprosthesis is presented.
2. Methods
Simulation of surgical treatment is realised in the following steps:
 creating geometrical models of bone tissue,
 model preparing to endoporosthesis fitting,
 project of endoprosthesis model and its implementation in bone model,
 endoprosthesis fitting,
 validation of simulation process.
The bone model was made in specialised medical system MIMICS 9.1 and MAGICS 9.51 by Materialise. To
define important anatomical characteristic of individual patient bone the CT examination had been made. The data
from CT recorded in DICOM format (Digital Imaging Communication in Medicine) was imported to Mimics. The
model of endoprosthesis was made in the commercial CAD system SolidWorks and imported to MIMICS in STL
format.
3. Results
In result of reconstruction procedure the bone model with tumour was obtained, and resection of tumour was
planned. Obtained by presented steps bone models allow one to perform a simulation of endoprosthesis
implantation (fig.1). Simulation of endoprosthesis implantation allows one to verify endoprosthesis construction
in regard to individual anatomy of the patient, through fitting particular parts to the patient’s bones (fig. 2).
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Fig. 1 Steps for preparing endoprosthesis implantation
Fig. 2 Simulations of fitting endoprosthesis to patients bones a)femur, b,c) tibia (view frontal and sagittal)
4. Discussion
Modern preoperative planning allows one to realise a virtual surgical operation before the real one. In each
stages of simulation there is a possibility to introduce dynamic modification in bone and endoprosthesis models
during patient therapy before operation. In consequence, it gives the surgeons a possibility to better prepare and
plan the operation and, in result, to reduce the risk of loosening and reimplantation.
References
[1]
[2]
M. Krzakowski, Onkologia Kliniczna. In: Nowotwory lite u dzieci. PZWL. Warszawa, Polska 2006.
W.Woźniak: Nowotwory lite u dzieci. Onkologia kliniczna, pod redakcją M.Krzakowskiego, BORGIS, t. II, wyd. I,
Warszawa 2001, 556-604.
[3] Tkaczyk A., Borkowski P.; Identyfikacja własności materiałowych tkanek kostnych na podstawie obrazów z tomografii
komputerowej. I Kongres Mechaniki Polskiej, Warszawa, 28–31 sierpnia 2007 r.
[4] Skalski K., Kwiatkowski K., Kedzior K., Cejmer W., Skoworodko J.: Application of a CT/CAD/CAE system to
preoperative planning and post–operative estimation of vertebroplasty, Proceedings of 12th IFToMM World Congress,
Besançon (France), 18 –21.06. 2007
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