Simultaneous strain measurements of knee ligaments

• Main Author: Teo, Shina Xue Na
• Other Authors: Chou Siaw Meng
• Format: Final Year Project
• Language: English
• Published: 2019
• Subjects: DRNTU::Engineering::Mechanical engineering
• Online Access: http://hdl.handle.net/10356/76425
• Institution: Nanyang Technological University

Ligament related injuries are extremely common amongst athletes and usually occurs from the subjected loads on the knee beyond its capabilities. The main objective of this study is to measure the four ligaments namely the anterior cruciate ligament (ACL), posterior cruciate ligament (PCL), medial collateral ligament (MCL) and lateral collateral ligament (LCL) of the knee simultaneously. Strain will be used as a quantifiable indicator for the experiment to analyse and understand the function of knee ligaments and its responses to passive flexion with tibia internal torque. In order to increase the degrees of freedom (DOF) for a more realistic condition to study the actual loading conditions of the knee, a new fixture for the experimental setup was designed and improved from the previous studies. With that, this study seeks to test the viability of the newly designed jig. Through this experiment, there were three sessions of data conducted where improvements were made throughout the study. As such, only the session 3 results were used as data for this study. It is seen that the MCL is recorded with the highest strain measurement despite the ACL being the main ligament of the knee. This can be explained by the limitations of the study where cadaveric knees are brought in from various studies before being tested for this experiment. Therefore, this could be improved on in future experiments. Six procedures were conducted on each specimen and at angles from 0° to 120° flexion with intervals of 10° and an extra point at 45°. The procedures are as follows: 1. Unloaded 2. Internal rotation 3. External rotation 4. Anterior-posterior loading translation of 22 N (22.24 N ≃ 22 N / 5 lbs) 5. Anterior-posterior loading translation of 44 N (44.48 N ≃ 44 N / 10 lbs) 6. Anterior-posterior loading translation of 67 N (66.72 N ≃ 67 N / 15 lbs)