How injury and pain reorganize the brain.

Gait, Arm Swing and Reorganizing the Brain

When we injure a body part there is a price to pay, how expensive it will be is entirely up to you. Upon injury, the brain takes note and typically dives into a backup plan of neurologic inhibition, neuro-protective tightness and alteration of motor patterns to protect that injured area and allow it to heal. Moderating and altering the forces and demands upon said tissues is the goal to enable healing, if we as humans, don’t get in the way first (“I have to get that run in, I am behind in my training with all these injuries !” or “Ah, its still not that bad, the pain wasn’t worse on Tuesday’s run, I will be ok.”). The bigger question for most folks is, will you listen to what your body is asking of you? Heed the warnings and messages, and your injury will come and go in a timely manner, ignore the messages and welcome to a chronic festering problem.

These protective mechanisms need to be in place, we just have to listen to them.  Failure to heed their warnings to dial things back and rest, recover and heal, the brain will make alternative changes out of necessity.

In the medpage today article in the references below, the authors discuss several important things.

“Getting a cast or splint causes the brain to rapidly shift its resources to make righties function better as lefties, researchers found.
Right-handed individuals whose dominant arm had to be immobilized after an injury showed a drop in (brain) cortical thickness in the area that controls primary motor and sensory areas for the hand, Nicolas Langer, MSc, of the University of Zurich in Switzerland, and colleagues reported.
Over the same two-week period, white and gray matter increased in the areas that controlled the uninjured left hand, suggesting “skill transfer from the right to the left hand,” the group reported in the Jan. 17 issue of Neurology.
The findings highlight the plasticity of the brain in rapidly adapting to changing demands, but also hold implications for clinical practice, they noted.”

This article highlights the rapid changes in motor programs that occur. It does not take long for the body to begin to develop not only functional adaptations but neurologic changes at the brain level within days and certainly less than 2 weeks.

So how long have you been in this pain ? If someone has to ask you this question, the process has already begun.

We tell our patients, if pain does not go away fairly quickly, that we need to get on top of the injury quickly. That is not to say you need to reach for the phone every time you have pain but you need to heighten your awareness of the injury’s status and  you need to make sure you are not driving session after session of training into a festering injury. If you do not let something heal and recover, the brain will find a way around it.  And it will imprint that new motor pattern into hard wiring, and into the hard wiring of other patterns, if you do not heed the warning signs.  This new wiring is a compensation pattern. And the longer it is there the more the neurologic pattern becomes embedded by layerings of myelin coating.  Which means that in the future, if you fatigue or injury another local tissue, this old compensation pattern is waiting in the shadows looking for an opening to rear its ugly head for old times sake.

Furthermore, on the topic of asymmetry, the above concept holds strongly true. In our clinics, we recognize asymmetry as a strong clinical finding. Despite the  Lathrop-Lambach study below, mentioning that they feel a 10% baseline asymmetry is the norm, if you do not rehab and correct both an injury and its new neurologic hardwiring changes, you have enabled and welcomed asymmetry. We feel, as many others do, that asymmetry can be a major component and predictor to injury. Logically, restoring as much symmetry as possible, both biomechanically and neurologically, is restorative and protective.

Don’t be a stoic knucklehead. Get your stuff fixed by someone who knows what they are doing. And remember, watching your gait on a treadmill or through some high tech gait analysis software and making recommendations from that information is just plain idiotic. Go see someone smart who can correlated it to examination findings. 

This article pertains to athletes and non-athletes of all walks of life. From 5 to 105 years of age, we are all susceptible to the brain’s overriding mechanisms. 

Shawn and Ivo


1. Broken arm can reorganize the brain.

Gait Posture. 2014 Jul 1. pii: S0966-6362(14)00610-9. doi: 10.1016/j.gaitpost.2014.06.010. [Epub ahead of print]
Evidence for joint moment asymmetry in  healthy populations during gait.
"We found a high amount of asymmetry between the limbs in healthy populations. More than half of our overall population exceeded 10% asymmetry in peak hip and knee flexion and adduction moments. Group medians exceeded 10% asymmetry for all variables in all populations. This may have important implications on gait evaluations, particularly clinical evaluations or research studies where asymmetry is used as an outcome. Additional research is necessary to determine acceptable levels of joint moment asymmetry during gait and to determine whether asymmetrical joint moments influence the development of symptomatic pathology or success of lower extremity rehabilitation.”