The Neurology of Injury and Healing
Would you consider an immediate manipulation for an acute ankle sprain?
Ok so my thoughts on why you should treat an acute ankle sprain using manipulation technique as soon as possible.
. Let’s first assume that you have established there is no fracture. Great. Now you have also established that there is clearly some form of ligament damage. Additionally, because of the uniqueness of the talus in that it is the only bone in the entire body with no muscle attachments, this is one of the few manipulable lesions which may genuinely present as a bone out of place. Remember that the talus is held in place part by the bony structures of the ankle mortice and part by the local ligaments. Now, consider that the shape of the talus from anterior to posterior is roughly triangular, with the posterior aspect being narrower than the anterior. That being the case, the forces which caused the ligament damage (anterior talofibular ligament) will also drive the talus in an anterior- lateral direction. Usually such force is restricted by the ligaments, but since they have failed in this case, the talus is free to drift unhinged. Once this has happened, there is likely to be a corresponding shift of the fibula from lateral to medial, occupying the space created by the broad body of the talus sliding anteriorly.
This shift creates a resistance to the talus simply sliding back into place. Now that the talus is sitting there it is actively impeding normal ankle joint function. What do the injured ligaments require for normal healing to take place? The answer is of course normal motion. Without normal motion the new fibres that arrive to affect the repair have no information regarding the direction of stresses that will be applied to the ligament. Those new fibres are therefore effectively “dumped”, lying in any random direction rather than placed to line in line with the stress. Because there is no motion (or inappropriate motion) there is no way of these new fibres ensuring correct alignment with motion. This means that these new ligament fibres create cross-linkages/adhesions at the joint which serve to further inhibit normal joint motion instead of facilitating good function. So on a biomechanical level manipulating the talus here would create a better healing environment and lead to a quicker, stronger repair of the damaged ligament structures.
On a neurological level, consider what happens in response to this injury. This swollen ankle with its significantly restricted joint motion will send little or no proprioceptive information regarding its changes in position, function, or terrain since there will be no changes occurring. It will certainly send no “normal” proprioceptive info since it is not functioning within its normal limits. What does the brain do when it stops getting information from a body part? We often hear it said that an area gets shut down. Unfortunately, that is not true. The brain does not just switch the area off and wait for healing to occur. The ankle wont suddenly pops a wee message up to the CNS saying “Yohoo! It is me. I know I have been off sick for three weeks, but I’m fit now and raring to go. Sign me back in.” Nope. When the brain draws a blank from an area it is expecting information from it does exactly what you would do when you do not get all the information you need. It does not go without anything but instead fills the blank with its own best guess.
It uses past experiences and future expectations to guess what information it should have received. If you want to experience this for yourself then just sit in front of a mirror and stare at one point in the mirror without allowing your eyes or your attention to drift from that point for two minutes. This means that your brain is deprived of the information that is usually provided by your eyes constantly scanning your surrounds. It will not take long for you to start to “see” that your head has changed shape or colour or even fallen off altogether!!
You see, your brain’s best guess is simply not very good. So, when you do not change the lack of good neurological feedback going from the ankle to the brain you invite the brain to substitute the information for gobbledegook. The longer you leave that ankle the more expert your brain becomes at filling the void with incorrect information and the more rehearsed that pathway becomes, meaning that when the ankle is healing and trying to send good proprioceptive output it is hampered by the changed pathway created by the blanks of information during injury.
Now, what we know from the literature is that soft tissue work, stretching, exercise, massage, mobilisation is all helpful but none of that creates a response from the muscle spindle or the Golgi tendon organ in the way that manipulation does. Because manipulation alone takes the joint into it is Para- physiological space it is uniquely placed to send a barrage of sensory information via the Fusimotor System. So manipulating this lesion early does two things from a neurological perspective.
1-it shortens the timescale for incorrect/unhelpful neurological information to be filling in gaps 2. It sends large amounts of “normal” neurological stimulus through the system, helping to keep the system functioning as close as possible to how it functioned prior to injury.
For these reasons I would have no hesitation in manipulating such injuries. I would of course inform the patient that the treatment will be momentarily painful but that it will lead to a quicker and better repair in the long term.