Valgus Loading™ and ACL Injury Prevention

One phrase that can sum up a knee injury: dynamic valgus moment. For those who have been lucky enough to have experienced this know how ugly a word valgus is. Saying go valgus yourself to someone is, well, shitty.

For the sake of simplicity, a dynamic valgus moment is essentially when a knee buckles inwards. Commonly, it occurs when an athlete decelerates and cuts simultaneously—leading to an ACL tear.

A majority of ACL tears are non-contact. Meaning they resulted from the individual’s movement putting their knee into valgus collapse position. Some reasons could be because of muscle strength imbalances, bone alignment, or improper mechanics. We are still advancing our understanding.

"A better understanding of injury mechanisms may provide insight that improves current risk screening and injury prevention strategies. Current findings support knee valgus collapse as a primary factor contributing to a non- contact ACL injury"  (Quatman et al. 2013).

Whatever the cause, healthcare professionals and biomechanical scientists understand that there are multiple forces at play in knee injuries. These forces should be mimicked or resisted in a way to help make the knee more resilient to the dynamic actions of sport and life. A joint support system and methodology needs to be dynamic in that it can also provide an injury prevention training element.

In training, we purposefully create targeted, and controlled, damage to our bodies with the intention of stimulating growth/ regeneration/ improvement. One example is weight lifting.

Lifting weights causes small tears so the body responds with an inflammatory response to repair the tissues and make it more resistant to the force that caused it. Applied resistance along multiple planes of a joint is similar to the weight lifting analogy and may advance injury interventions.

The future of injury prevention methods will occur with additional objective measurements and functional tools. BRACEUNDER provides a new methodology for joint injury prevention/ rehab training.

The smart-tech provides us with an external force combined with data that gives us the tool to create useful quantitative metrics on a biomechanical level - thereby enhancing understanding through objective measures.

Multiple measurements are relayed to an app on a tablet where we drive the technology and utilize the multiple data points. 

Use case 1:

Valgus Loading™—applying a measured force to the knee that pulls the knee into a valgus position. The wearer then performs functional movements (i.e. squats, single leg presses) while maintaining proper biomechanical alignment, resisting the force. Even slight valgus events are identified visually on the graph (see below); the movement pattern quality is reviewed, while therapeutic training is being performed.

"Training that reduces the external valgus moment can reduce the ACL strain and thus may help athletes reduce their overall ACL injury risk"  (Shin et al. 2009).

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Sources:

Quatman, CE, & Kiapour, AM. (2013). Preferential loading of the ACL compared with the MCL during landing a novel in sim approach yields the multiplanar mechanism of dynamic valgus during ACL…. The American journal…. doi:10.1177/0363546513506558

Shin, C. S., Chaudhari, A. M., & Andriacchi, T. P. (2009). The effect of isolated valgus moments on ACL strain during single-leg landing: a simulation study. Journal of biomechanics, 42(3), 280–285. doi:10.1016/j.jbiomech.2008.10.031

Teddy Hodges