Simultaneous strain measurement of knee ligaments

• Main Author: Pang, Jing Kang
• Other Authors: Chou Siaw Meng
• Format: Final Year Project
• Language: English
• Published: 2019
• Subjects: DRNTU::Engineering::Mechanical engineering::Bio-mechatronics
• Online Access: http://hdl.handle.net/10356/77512
• Institution: Nanyang Technological University

The knee is one of the largest and most important joint in the human body. To perform its various functions, knee stability must be kept and ligaments are the primary structure in the knee that provides stability. The 4 ligaments in the knee are the Anterior Cruciate Ligament (ACL), Posterior Cruciate Ligament (PCL), Medial Collateral Ligament (MCL) and Lateral Collateral Ligament (LCL). They are essential in providing support to motions in all directions and several demanding manoeuvres. Due to this very reason, ligament injuries are the most common knee injuries and a high percentage of it occurs in athletes; with the ACL having the highest rate of injury. As the main stabilizing ligament of the knee, the ACL is essential in resisting hyperextension of the knee in several degrees of freedom. The purpose of this study is to compare the strains in each ligament under various loading conditions before and after ACL rupture. All experiments were conducted in Academia at Singapore General Hospital. The experimental parameters are passive flexion-extension, 5 Nm internal and external tibial torque and 22 N, 44 N and 67 N anterior loading of the tibia. Strain values for all ligaments prior to ACL removal are consistent with past literature. The MCL is determined to be the secondary load bearing ligament of the knee as it has the highest increase in strain percentage after cutting the ACL. After ACL reconstruction, all of the ligaments suffered a decrease in load bearing capabilities and anatomical stability could not be achieved. LCL constantly displayed decrease in strain for all experiment parameters. Future work is required to eliminate several of the experimental errors that could be the cause of the abnormality of the results described.