The turned out foot. How far ahead (and how fast) can you think ?
There are many causes of the turned out foot. The above slide is just one of many logical and possible chain of events.
There are also reasons above the neck that cannot be ignored in creating the externally rotated foot (and in resolving it). Things are not always biomechanical in origin so remember this when you are continually doing activation and rehab interventions to get more glute or drive more internal limb spin and your results are met with a non-response.
Most of us like a biomechanical line of thinking when it comes to apparent biomechanical aberrancies from the norm. However, more often than you probably think (go back and listen to podcast 58 on Cortical Brain Mapping of injuries), several more purely neurologic reasons are plausible. For example, changes in input/output in unilateral activity within the pontomedullary reticular formation (PMRF) of the brain can lead to inhibition of the posterior chain muscles below the T6 spinal level (And anterior muscles above T6. And what is awesome is that there are ways to test this kinda stuff on a physical exam ! However, this blog post is not the place to teach these neurologic examination procedures. But, if this sounds like Janda’s Upper and Lower Crossed Syndromes you are thinking soundly. Just remember though, if you are fixing what you see, you may not be fixing the problem, fix the cause that drove what you are seeing. If you know your functional neurology you will know where these things come from, they are a cortical phenomenon).
Of the posterior compartment muscles below T6, the gluteus maximus is probably the largest of this group and when it is inhibited there is loss of control of its ability to stabilize single leg stance. One strategy around a stability challenge would be to turn the foot/leg into the frontal plane (toe out) via external limb rotation. Now we can use the remaining muscles in both the sagittal and frontal planes ! We are always more stable when we can engage two or more cardinal planes at the same time.
There are many more reasons for the externally rotated limb/foot, for example vestibular dysfunction, cerebellar dysfunction, core dysfunction, impaired normal arm swing and the list goes on. We have talked about many of these reasons on many of our blog posts and podcasts.
Mental gymnastics when it comes to the brain are important, Keep your gait and human movement game sharp, work through scenarios in your head regularly because it is what is necessary when you are working up a client.
Shawn and Ivo
the gait guys