Abstract
Hip Resurfacing (HR) is nowadays widely used as an alternative to Total Hip Replacement (THR), especially for the young and active patients. Because of the more physiological distribution of the load in the femur, this technique is particularly known to reduce bone loss due to stress shielding behaviour, a major problem encountered with THA. Different computational studies have analysed the performance of HR prostheses. Therefore, the purpose of this study is to apply a computational approach, in fact a bone remodelling analysis, in order to investigate its application to evaluate the bone structure changes postoperatively.
A Finite Element model was developed of a femur with HR prosthesis. The model was reconstructed starting with the femur medical images, and then the prosthesis was positioned in the clinical implantation angle (5° valgus). A cement mantle thickness of 1mm was included. Then a Finite Element Analysis in combination with a bone remodelling model (bone material properties) was performed. The results obtained predict as there is a certain bone loss in the superolateral and inferior medial zone. Additional bone material apposition is locally found with the aim of fixing the implant stem on the medial side, but also a remarkable distal ingrowth around the stem tip. All these findings are in good qualitative agreement with clinical observations.
We conclude that the numerical simulation used in this study is a useful tool in predicting bone remodelling inside a cemented HR prosthesis. This kind of methodologies will help on the design of devices, surgical techniques, etc.
Correspondence should be addressed to EORS Secretariat Mag. Gerlinde M. Jahn, c/o Vienna Medical Academy, Alserstrasse 4, 1090 Vienna, Austria. Fax: +43-1-4078274. Email: eors@medacad.org
