Coordination of leg swing, thorax rotations, and pelvis rotations during gait: The organisation of total body angular momentum

"In walking faster than 3 km/h, transverse pelvic rotation lengthens the step (“pelvic step”).
The shift in pelvis–thorax coordination from in-phase to out of phase with increasing velocity was found to depend on the pelvis beginning to move in-phase with the femur, while the thorax continued to counter rotate with respect to the femur. "

We are always trying to bring greater understanding to this group at TGG regarding gait mechanics. One must understand the implications of rotational work, and anti-rotational work on the phasic and antiphasic nature of the thorax and the pelvis. We have talked about becoming more phasic when there is spine pain. With today's study, we delve just al little deeper, particularly noting how the pelvis and the femur moving together first, before that is offset by the antiphasic nature of the thorax at higher speeds of gait.
This article uses the terms in phase and out of phase. We have learned over time that those terms to relate more so the description of how the limbs are, or are not, pairing up when a couple is walking together. None the less, the reader here should understand how they are referring to out of phase as antiphasic.

http://www.sciencedirect.com/…/article/pii/S096663620700135X

 

Arm swing and hip ranges.

Most folks think they know a sufficient amount about arm swing, but the truth speaks otherwise for many. Many know heaps about upper quarter biomechanics and how to assess and evaluate the joints of the upper quarter but they have no clue what to look for when it comes to the client using the limb in locomotion. What really happens during the complex arm motions during gait and various forms of locomotion in runners and throwing sports ?
"For the first time, we provide evidence that the spinal interneuronal networks linking the forelimbs and hind limbs are amenable to a rehabilitation training paradigm. Identification of this phenomenon provides a strong rationale for proceeding toward preclinical studies for determining whether training paradigms involving upper arm training in concert with lower extremity training can enhance locomotor recovery after neurological damage.” -Shah et at, Brain 2013 Nov

"Our results demonstrate that altered hip rotational range of motion, measured clinically, has a direct effect on the amount of external rotation torque and horizontal adduction range of motion of the shoulder during the throwing motion." -Laundner et al, (article below)

Want to dive deeply into arm swing ? Want to really know what you are doing and missing ? Goto our blog (thegaitguys.tumblr.com) and in the search box type "arm swing". You will find nothing short of dozens of articles we have written on the topic.

The relationship between clinically measured hip rotational motion and shoulder biomechanics during the pitching motion

Kevin Laudner, Regan Wong, Takashi Onuki, Robert Lynall, Keith Meister

http://www.jsams.org/article/S1440-2440(14)00137-6/abstract

Awkward photos…Date smarter but necessarily walk that way…Take a look at this photo from an airplane magazine I was leafing through on my way home from teaching a recent needling seminar.I am not really interested in matchmaking (which…

Awkward photos…Date smarter but necessarily walk that way…

Take a look at this photo from an airplane magazine I was leafing through on my way home from teaching a recent needling seminar.

I am not really interested in matchmaking (which this ad is for), but the “awkwardness” of the gait caught my eye (not much on the gait cam this time, sorry).

Yes, their feet and legs seem to be in synch (for the most part), but take a look at the arms and hands. First of all, he has his right hand in his pocket, which will restrict its motion during forward movement of his left leg. In the shot, his right leg is forward (as is hers), though they are slightly out of synch. His left arm and hand don’t move forward that much in that he adducts it across his body, so he seems to move his left shoulder up and forward to compensate. She appears to be resisting this motion somewhat with her right arm as her right leg comes forward and she needs to lean her body to the right. Also note the increased abduction of her left arm and forearm as it extends in tandem with her left leg and thigh.

Try walking with your right arm moving forward with your right leg. Notice how your right shoulder resists moving forward in tandem with the right hip? This is phasic, as Dr Allen likes to say, and because there is not an opposite force to counteract the forward movement of the hip in the saggital plane, you often lean to move the center of gravity to that side in the coronal plane.

Wouldn’t it make slightly more sense, when walking hand in hand to have the opposite legs in synch, rather the same ones? Hmm…Food for thought and fodder. All that from a  little picture : )

This Client went Phasic in their Gait. Do you know what that means ? We do, and so does McGill, Liebenson, Cook and many others.

Long ago on this blog we showed and discussed a video (link) that discussed Stu McGill's research of the human movements of Georges St-Pierre and David Loiseau. The basic tenets of that video were that the hips and shoulders are used for power production and that the spine-core are used for creating stiffness and stability for the ultimate power transmission through the limb.  He made it clear that if power is generated from the spine, it will suffer. 

Here on TGG we have long talked about phasic and antiphasic motions of the arms and shoulder-pelvic blocks during gait and locomotion/sport activity.  Many of our 1000+ blog writings and 80 podcasts have talked about spine pain and how spine pain clients reduce the antiphasic rotational (axial) nature of the shoulder girdle and pelvic girdle. In the video above, we see anything but antiphasic gait, to be clear, this is a classic representation of a phasic gait. This is pathologic gait, the frontal plane sway is exaggerated and necessary because there is no axial antiphasic motion.  There is essentially frozen arm and torso movements. This client has a long standing history of severe spine trauma and pain, their central pattern generators (CPG) had to make this motor pattern choice in an attempt to avoid pain and negotiate force streams across trauma zones. If you are curious and wish to go deeper down this rabbit hole, read the 30+ articles we have produced more specifically on arm swing and locomotor phasics, just click here.

In these types of cases, the client subconsciously makes the subcortial pattern choice (overrides the normal CPG) to rotate them as a solid unit to reduce spine rotation, axial loading and compression.  We could say that quite often spine pain disables the normal arm-leg pendulums via altering the shoulder-torso and hip-pelvis phasics and the CPG that dictates them. Normally, the spine and core must present sufficient amounts of recruited stiffness, yet mobility where necessary, to enable the locomotive power and velocity generated by movements of the shoulders and hips. These are the two main portals of limb movement off of the spine/core.  These principles holds true in gait and sport. For and interesting example, in human gait the psoas is not entirely a hip flexor initiator when it comes to leg swing, it is a huge hip flexion perpetuator. The initial hip flexion in human gait comes from derotating the obliqued pelvis, via abdominal contraction, on a stiff and stable spine.  Once the pelvis rotation is initiated, the femur can further pendulum forward (via contraction of the psoas and other muscles) on the forward accelerated pelvis in the hip joint proper creating an energy efficient movement (the towel flick/whip effect). This premise holds true in gait, running, kicking etc.  This is a solid principle of effective and efficient human locomotion. This principle also holds true for a punch or throwing an object, the stable torso/spine provides a stable anchor upon which to accelerate the arm in order to create a high velocity limb movement with power.  But here is where we get annoyed much of the time.  (Soap box Tangent coming up) How often do you read articles about tight ITBand, tight psoas, tight piriformis and the like ?  As a “diagnosis” these are weak and they are the “go to diagnosis or cause” of the unseasoned clinician, trainer, coach, therapist. If we all are to be really good at our job, we must go beyond what we see in someone’s gait (since it is the compensation) and go beyond the CNS neuroprotective strategy of tightness/shortness when there is weakness or motor pattern failure.  This does not mean that you cannot, or should not, incorporate restoration methods and principles to restore length-tension relationships in your client, it means you have to resolve ALL of the problems, including the aberrant CPG they have set up as a protective default to avoid injury or further injury. 

In the case above, returning the discussion to arm and leg swing, one must understand clearly that faulty arm swing patterns and lack of antiphasic torso and pelvis oscillation is a product of surgery,  trauma and more so, pain. The client is avoiding the antiphasic presentation (hence, he is phasic) for a reason and coaching more arm swing would be just about the dumbest intervention, so don’t be “that guy”. We know this is an altered motor pattern choice, not a new fixed set point. We know this because on clinical examination the range is available, we know because we examined for it, it is just not being used.  In an example of this same principle, in this case talking hip ranges of motion, McGill discusses the same in his paper*:

“Despite the large increases in passive hip ROM, there was no evidence of increased hip ROM used during functional movement testing. Similarly, the only significant change in lumbar motion was a reduction in lumbar rotation during the active hip extension maneuver (p < 0.05). These results indicate that changes in passive ROM or core endurance do not automatically transfer to changes in functional movement patterns. This implies that training and rehabilitation programs may benefit from an additional focus on grooving new motor patterns if newfound movement range is to be used.”

Think about that next time you stretch, or are stretched by someone. As we have said before, just because you increase someone’s range of motion, does not mean they will be able to incorporate that range of motion into a movement pattern, or compensation pattern for that matter. It is only ¼ of the equation: Range of Motion,  Skill (or proprioception),  Endurance (or the proportion of slow twitch muscle) and Strength (the proportion of fast twitch muscle). There is our S.E.S. mnemonic again.

In this video case, lack of NORMAL antiphasic spinal motion (torso and pelvis moving opposite one another) is noted. Without the obliqued pelvis the swing and stance phases will be impaired. The psoas may have to become more of a hip flexor initiator, AS WELL AS the perpetuator of limb swing, because there is no pelvic obliquity from the antiphasic principles to drive it from. And so, when you see this fella in your office with bilateral tight psoas/hip flexor complex and tight quadriceps mechanisms with resultant impaired glutes and hip extension, please do not begin lengthening them as your point of initiation.  They are that way because he has gone phasic in his gait.  Change the motor patterns that drive this as best as possible, restore any weaknesses that are contributory to, or initiate, these motor patterns and then, if needed, encourage some progressive new length-tension in these muscle groups as improved motor patterning evolve to allow for it.  You are likely going to have to go back and reteach and restore primitive and postural sensory motor windows in these cases, so be patient, be kind, be wise. Oh, and do not forget that with impaired hip function, there will most likely be impaired ankle rocker,  you are going to need a wide angled lens to see, capture and remedy this lads problems.

On another note, can you imagine what this client’s video gait analysis would show and interpret ? Let alone the diagnostics and recommendations that could come from it?  What about the appearance of their foot pressures across a dynamic foot pressure plate (or God forbid a static one !), surely what is seen at the foot is this client’s problem (not !) And forgive those poor fools who recommend a shoe for this client based off of just those mediums alone.  Without a complete hands-on clinical examination to correlate gait cycle observances, any recommendations for this case will be traumatic on many levels. 

Today’s bottom line……. read, learn, think, stay hungry, be wise.

Shawn and Ivo, The Gait Guys

* Improvements in hip flexibility do not transfer to mobility in functional movement patterns.  Moreside, Janice: McGill, Stuart

link: http://journals.lww.com/nsca-jscr/Fulltext/2013/10000/Improvements_in_Hip_Flexibility_Do_Not_Transfer_to.1.aspx