Untitled in english

Author(s)

Gilberto Garcia Del Pino

• Document type: Doctoral Thesis
• Press: São Paulo.
• Institution: Universidade de São Paulo (USP). Escola Politécnica (EP/BC)
• Defense date: 2001-08-03

Examining board members

Edison Gonçalves; Marcilio Alves; Julio César Escarpenter Buliés; Carlos Alberto Nunes Dias; Mikiya Muramatsu

• Advisor: Edison Gonçalves

Abstract

This research focuses the interaction of the Total Hip prosthesis and the bone and its useful life. The study of the useful life of these implants has become very important especially for young patients, which have been submitted to implant surgeries. Firstly, theoretical study was made based on previous works, using data obtained by modeling, laboratory work and from the clinical evolution of patients with different types of Total Hip prosthesis. The attendance of surgeries of implantation of Total Hip prosthesis was accomplished. The theoretical study presents different problems of prosthesis-bone interaction, which still haven´t been solved. The influence of different variables in the transmission of the tensions and the deformation energy of the bone was studied by creating numeric models of implants with Finite Elements Method (FEM). The FEM developed were used to evaluate the contact between the head of the prosthesis and the acetabular component, and the interaction of the femural component with the bone. Several routines in \"C\" language were developed for the analysis of the results and organization of the outputs obtained from the FEM. This data processing was used in a further statistical analysis. The representative theoretical models of the useful life of the prosthesis were developed using constants obtained by multiple regressions of the FEM models outputs. The results were tested in physical models using the technique of digitalholographic interferometry and were adjusted to a digital system of images processing. The adjustment of the holographic system may be applied in further research. (AU)