Protecting Athletes’ Knees Using Biomechanics And Motion Analysis

Knee injuries are among the most common in sports. Anterior cruciate ligament (ACL) injury can be career ending in some cases, while more common pathologies, such as patellofemoral pain syndrome, may keep athletes off of the field for weeks. In a sports setting, these injuries are often the result of underlying deficiencies in the athlete’s motor control and overall movement patterns. Fortunately for young athletes, sports biomechanists and biomedical engineers have developed reliable techniques using three-dimensional motion analysis that can identify injury risk based on an athlete’s movement patterns.

Motion capture technologies that are commonly used to make video games or animated films can also quantify the net loading that athletes transmit through their knees using a technique called inverse dynamics. Inverse dynamics uses segmental motions and inertial properties, along with information from force platforms underneath the athlete’s foot and the laws of Newtonian physics, to calculate the net forces and moments at the ankle, knee, and hip. Scientific studies have determined that abnormal frontal plane moments in the knee during landing can predict an athlete’s risk of ACL injury. Similar movement patterns have also been associated with patellofemoral pain.

Once an athlete has been identified as being at risk for one of these knee injuries, biomechanists and biomedical engineers can begin to correct deficiencies in their motor control patterns. This is often accomplished through neuromuscular training programs that drill movement and landing patterns into the athlete’s subconscious through feedback and repetition.