Enclosed Electronic System for Force Measurements in Knee Implants

Sensors

David Forchelet¹  Matteo Simoncini³  Arash Arami²  Arnaud Bertsch¹  Eric Meurville³  Kamiar Aminian²  Peter Ryser³ 

[1] Microsystems Laboratory (LMIS4), École Polytechnique Fédérale de Lausanne (EPFL), CH-1015 Lausanne, Switzerland; E-Mails:;Laboratory of Movement Analysis and Measurement (LMAM), École Polytechnique Fédérale de Lausanne (EPFL), CH-1015 Lausanne, Switzerland; E-Mails:;Laboratory of Microengineering for Manufacturing (LPM), École Polytechnique Fédérale de Lausanne (EPFL), CH-1015 Lausanne, Switzerland; E-Mails:

关键词: total joint arthroplasty;    strain sensor;    load monitoring;    instrumented implant;    biomechanics;   

DOI  :  10.3390/s140815009

来源: mdpi

【 摘 要 】

Total knee arthroplasty is a widely performed surgical technique. Soft tissue force balancing during the operation relies strongly on the experience of the surgeon in equilibrating tension in the collateral ligaments. Little information on the forces in the implanted prosthesis is available during surgery and post-operative treatment. This paper presents the design, fabrication and testing of an instrumented insert performing force measurements in a knee prosthesis. The insert contains a closed structure composed of printed circuit boards and incorporates a microfabricated polyimide thin-film piezoresistive strain sensor for each condylar compartment. The sensor is tested in a mechanical knee simulator that mimics in-vivo conditions. For characterization purposes, static and dynamic load patterns are applied to the instrumented insert. Results show that the sensors are able to measure forces up to 1.5 times body weight with a sensitivity fitting the requirements for the proposed use. Dynamic testing of the insert shows a good tracking of slow and fast changing forces in the knee prosthesis by the sensors.

【 授权许可】

CC BY   
© 2014 by the authors; licensee MDPI, Basel, Switzerland.