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Knee Valgus and ACL injuries.
A reflective thread on what we can say.
If you retweet what should be a comment I'm not responding :)
Keep it clean!
Let's go 1/x
A reflective thread on what we can say.
If you retweet what should be a comment I'm not responding :)
Keep it clean!
Let's go 1/x
Large and violent amounts of dynamic knee valgus are absolutely one potential method of tearing the ACL. Both cadaver studies and video analyses will confirm this.
https://pubmed.ncbi.nlm.nih.gov/32561515/
https://pubmed.ncbi.nlm.nih.gov/32561515/
Valgus is composed of hip adduction, hip Internal rotation and knee abduction. One question now arises:
1. If someone lands in more valgus compared to an average are they more likely to move into the "catastrophic" amount of valgus
Permit an analogy...3/
1. If someone lands in more valgus compared to an average are they more likely to move into the "catastrophic" amount of valgus
Permit an analogy...3/
You're dead if you fall off the cliff. The thing that knocks you off a cliff are hurricanes. Are you safer 10 feet from the cliff or 50 feet from the cliff? To a hurricane that 40 feet might mean nothing. Valgus could be the same thing. This is reflected in some studies...4/
Krosshaug ( https://pubmed.ncbi.nlm.nih.gov/27252548/ ) would suggest that the kinematics/kinetics of how you land won't tell you if you are more likely to damage your ACL (it doesn't matter how close you are to the cliff).
However, other researchers would argue the opposite...5/
However, other researchers would argue the opposite...5/
Both Hewett (2005) and Myer (2015) suggested that those who have a high Knee Abduction MOMENT (closer to the cliff) are more likely to suffer the catastrophic movement pattern.
https://pubmed.ncbi.nlm.nih.gov/15722287/
https://pubmed.ncbi.nlm.nih.gov/24687011/
Of note, the kinematic (what you look like)...6/x
https://pubmed.ncbi.nlm.nih.gov/15722287/
https://pubmed.ncbi.nlm.nih.gov/24687011/
Of note, the kinematic (what you look like)...6/x
was not related to future injuries. You know, the thing you observe and potentially try to correct. Both hip adduction and knee abduction weren't increased in the injured group.
Just the knee ABDuction Moment.
So, now we have conflicting research on risk factors. 7/x
Just the knee ABDuction Moment.
So, now we have conflicting research on risk factors. 7/x
Perhaps intervention studies can help. If the knee abduction moment is a potential risk factor is it something that MUST be corrected to decrease injury risk?
There are excellent researchers providing very strong evidence that neuromuscular training programs (e.g FIFA 11 Plus).
There are excellent researchers providing very strong evidence that neuromuscular training programs (e.g FIFA 11 Plus).
...can reduce ACL injury risk. Awesome.
So why did they do that. Do those programs change movement patterns?
Again, it depends who you ask and what you measure.
This SR suggests that KINEMATICS don't change
https://pubmed.ncbi.nlm.nih.gov/28759729/
But, the kinetics can change!
So why did they do that. Do those programs change movement patterns?
Again, it depends who you ask and what you measure.
This SR suggests that KINEMATICS don't change
https://pubmed.ncbi.nlm.nih.gov/28759729/
But, the kinetics can change!
Other papers suggest kinetics/kinematics don't change
https://pubmed.ncbi.nlm.nih.gov/26400955/
So, we know neuromuscular training programs can help prevent injuries but do we have a proven mechanism? i.e is it because Valgus changed? or something else?
https://pubmed.ncbi.nlm.nih.gov/26400955/
So, we know neuromuscular training programs can help prevent injuries but do we have a proven mechanism? i.e is it because Valgus changed? or something else?
In order to argue that changing valgus (the KAM) is a mediating variable for injury reduction we would have to control for ALL of the other factors in an injury prevention program. You'd have to have at least two groups that did:
...
...
...plyometrics, sprints, balance, hops, nordic hamstrings, progressive overload etc and the only difference between the groups was that one was given instruction on how to minimize valgus and the other wasn't. You'd then have to measure valgus.
If the group...
If the group...
that attempted to change valgus, succeeded in changing it and had a greater reduction in injuries then we might be able to say valgus and its correction is a mediating variable in injury prevention.
Right now we can just say:
Right now we can just say:
1. Valgus might be a risk factor but we aren't sure
2. Everybody should do the wonderful intervention program
3. Injury prevention could be occurring via the development of a number of factors but we don't know what they are
2. Everybody should do the wonderful intervention program
3. Injury prevention could be occurring via the development of a number of factors but we don't know what they are
Conclusion and caveats of doubt for this dialectic.
A high knee abduction moment (one aspect of valgus) might be something worth addressing. It very well could be a risk factor. Trying to change it seems reasonable buy so does having some doubt.
Adios
A high knee abduction moment (one aspect of valgus) might be something worth addressing. It very well could be a risk factor. Trying to change it seems reasonable buy so does having some doubt.
Adios
