Kinematics (the movement of the bones) plays a crucial role in understanding knee joint mechanics and how the knee avoids or becomes injured. Unfortunately, measuring knee joint motion is limited by soft tissue artifact (movement of the skin) when doing analysis with reflective markers placed on the skin (the most common and accessible approach). As such, we have explored this issue and the limitations of motion analysis for measuring knee joint kinematics with by measuring soft tissue artefact and knee joint motion during walking and cutting motions in vivo, with pins inserted directly into the bones so we know exactly how they are moving. This research revealed, in fact, that many commonly held beliefs about knee joint motion walking were not reflective of what was really going on, potentially biasing how we may approach the development of knee prostheses or even rehabilitation.
Our objectives are to improve the validity and accuracy of knee and hip joint motion analysis and improve our current understanding of the motions of these joints. Our collaborations with scientists at the Aalborg University in Denmark have explored new solutions to the problem of soft tissue artefact. We discovered that a new approach was needed to reduce soft tissue artifact and we have published a model that effectively does this.
Through these collaborations we continue to explore the best way to measure joint motions so that we can continue to evolve our understanding of just how the knee works.