In basketball, 70% of those who sprained their ankle had a re-injury of the same ankle. Other issues with ankle sprains are the residual symptoms of swelling, pain, and instability (“giving way”).
One of the theories as to why an ankle keeps getting re-injured involves more than just the ankle. It could also involve the central nervous system. This means it’s just as important to address the CNS as it is the ankle itself.
Rehabilitation is critical for a chronic ankle sprain. Dynamic balance exercises need to be performed to resolve the functional instability. Also, the invertor muscles need to be examined to make sure they are “turned on” and functioning properly.
Do you have a history of ankle sprains? Does your ankle seem to “give out” on you? Call us today at Neurotensegrity Wellness Center. Together, we can provide the right rehabilitation for you! (540) 420-7048
For those who like a little more detail!
Delahunt E. Neuromuscular contributions to functional instability of the ankle joint. Journal of Bodywork and Movement Therapies. 2007;11:203-213.
There are two distinct categories of instability that occur in chronic ankle instability: mechanical instability and functional instability. Mechanical instability is where there is ligament damage/laxity in the ankle joint following the ankle sprain. Because of this damage, the ankle joint moves more than it is supposed to. This increases the risk of the person re-injuring his/her ankle. Functional instability is where there may not be any ligament damage that allows the ankle joint to move more than it is supposed to. You can have functional instability without mechanical instability.
Functional instability may occur when the mechanoreceptors of the ligaments are damaged. Because these ligaments are damaged, afferent impulses from these mechanoreceptors aren’t able to get their message into the nervous system. Mechanoreceptors are supposed to tell your brain how your ankle is moving and where it is located in space at that moment. Mechanoreceptors also help the reflex system in your body that allows you to maintain your balance. Without the information from the mechanoreceptors, balance issues occur.
The best way to determine if functional instability is present is to have the person perform a Star Excursion Balance Test, which is more dynamic in nature than merely standing on one leg. The reason for this is because mechanoreceptors in the joint are only active towards end range of motion.
While mechanoreceptor damage in ligaments has been mentioned multiple times throughout these blogs, another aspect of the chronic ankle instability examined is muscular deficits. One of the interesting points investigated is eccentric invertor strength deficits. It is proposed that the muscles “shut off” after the ankle sprain so the muscles wouldn’t pull on the damaged ligaments and damage them more than they already are. This issue occurs when the ligaments have healed and these muscles haven’t “turned back on”. By remaining “shut off”, the person is prone to re-injuring the ankle.
But the issue doesn’t stop at the foot. Remember that the ankle is connected to the rest of the body, including the brain. One of the extras added to the functional instability explanation involves the role the central nervous system plays in the sprained ankle.
Example: An ankle sprain occurs. The person’s ankle joint movements are altered in a negative way. The ankle sprain heals. The person’s ankle joint movements don’t go back to normal. When the person merely walks, his/her ankle motion isn’t the same as it was before the injury. This alteration leads to an increase risk of re-injury. Not only that, but there is a decrease in balance and strength (proprioceptive deficit). This change in movement isn’t only occurring at the ankle joint, but also the entire body. The person has altered his/her normal movement patterns due to the ankle sprain, so there isn’t too much stress placed on the ankle. These movement patterns remain altered even after the ankle has healed. This means the central nervous system may need to be addressed just as much as the ankle to interrupt this new movement pattern. A possible way to re-establish the movement pattern prior to the ankle injury is through adjustments.