Mapping Stresses on the Tibial Plateau Cartilage in an Ovine Model Using In-Vivo Gait Kinematics

• Published in: Annals of biomedical engineering Vol. 49; no. 5; pp. 1288 - 1297
• Main Authors: Vakiel, Paris, Shekarforoush, Mehdi, Dennison, Christopher R., Scott, Michael, Muench, Gregory, Hart, David A., Shrive, Nigel G.
• Format: Journal Article
• Language: English
• Published: Cham Springer International Publishing 01.05.2021; Springer Nature B.V
• Subjects: Biochemistry; Biological and Medical Physics; Biomedical and Life Sciences; Biomedical Engineering and Bioengineering; Biomedical materials; Biomedicine; Biophysics; Bragg gratings; Cartilage; Cartilage diseases; Classical Mechanics; Contact stresses; Etiology; Gait; In vivo methods and tests; Joint diseases; Joints (anatomy); Kinematics; Knee; Original Article; Osteoarthritis; Parallel degrees of freedom; Stress concentration; Treadmills; Biomechanics; Fibre optic sensors; Mechanical stress; FBG sensors
• ISSN: 0090-6964; 1573-9686
• DOI: 10.1007/s10439-020-02650-6

Understanding stresses within the knee joint is central to understanding knee function, and the etiology and progression of degenerative joint diseases such as post-traumatic osteoarthritis. In this study, in vivo gait kinematics of four ovine subjects were recorded using a highly accurate I nstrumented S patial L inkage ( ISL ) as each subject walked on a standard treadmill. The subjects were then sacrificed, and the right hind limbs removed. Ten purpose-built F ibre B ragg G rating ( FBG ) sensors were positioned within each stifle joint and used to measured contact stresses on the articulating surface of the tibial plateau as the recorded gait was replicated using a 6-degrees-of-freedom parallel robotic system. This study provides the first accurate, direct measurement of stress in a joint during in vivo gait replication. It was hypothesized that the results would indicate a direct link between gait kinematics and measured stress values. Contrary to this expectation no direct link was found between individualistic differences in kinematics and differences in stress magnitudes. This finding highlights the complex multifactorial nature of stress magnitudes and distribution patterns across articular joints. The results also indicate that stress magnitudes within the knee joint are highly position dependent with magnitudes varying substantially between points only a few mm apart.