Arm swing in gait and running. Why it is crucial, and why it must be symmetrical.

It becomes clear that once you get the amazing feats seen in this video out of your head, and begin to watch just the variable use of the arms that you will begin to appreciate the amazing need for arm swing and function in movement.

We have written many articles on arm swing and its vital importance in gait and running. Have you missed all these articles ?  If so, go to our blog main page, type in “arm swing” in the search box and you will have a solid morning of readings at your fingertips.  We are still not done writing about this most commonly forgotten and overlooked aspect of gait and running analysis, and we probably never will be done.  Why is no one else focusing on it ?  We think it is because they do not see or understand its critical importance.

Without the presence and use of the arms in motion things like acceleration, deceleration, directional change, balance and many other critical components of body motion are not possible.

What is perhaps equally important for you to realize, as put forth in:

Huang et al in the Eur Spine Journal, 2011 Mar 20(3) “Gait Adaptations in low back pain patients with lumbar disc herniation: trunk coordination and arm swing.”

is that as spine pain presents, the shoulder and pelvic girdle anti-phase begins to move into a more in-phase favor.  Meaning that the differential between the upper torso twist and pelvic twist is reduced. As spine pain presents, the free flowing pendulum motions of the upper and lower limbs becomes reduced to dampen the torsional “wringing” on the spine. When this anti-phase is reduced then arm swing should be reduced. The central neural processing mechanisms do this to reduce spinal twisting, because with reduced twist means reduced spinal motor unit compression and thus hopefully less pain. (Yes, for you uber biomechanics geeks out there, reduced spine compression means increased shear forces which are favorite topics of many of our prior University instructors, like Dr. Stuart McGill). The consequence to this reduced spinal rotation is reduced limb swing.  And according to

Collins et al Proc Biol Sci, 2009, Oct 22 “Dynamic arm swinging in human walking.”

“normal arm swinging requires minimal shoulder torque, while volitionally holding the arms still requires 12 % more metabolic energy.  Among measures of gait mechanics, vertical ground reactive moments are most affected by arm swinging and increased by 63% without arm swing.”

So, it is all about efficiency and protection. Efficiency comes with fluid unrestricted movements and energy conservation but protection has the cost of wasting energy and reduced mobility through a limb(s) and spine.

In past articles we have carried these thoughts into historical functional needs of man such as carrying spears and of modern day man in carrying briefcases.   Today we show a great high functioning video of another parkour practitioner.  Parkour is a physical discipline and non-competitive sport which focuses on efficient movement around obstacles.  Watch closely the use of the arms. The need for arm use in jumping, in balance, in acceleration etc. It becomes clear that once you get the amazing feats seen in this video out of your head, and begin to watch just the use of the arms that you will begin to appreciate the amazing need for arm swing and function in movement.

There is a reason that in our practices we treat contralateral upper and lower limbs so much.  Because if you are paying attention, these in combination with the unilateral loss of spinal rotation are the things that need attention. 

Yup, we are The Gait Guys….. we have been paying attention to this stuff long before the functional movement assessment programs became popular.  If you just know gait, one of the single most primitive patterns other than crawling and breathing and the like, you will understand why you see altered squats, hip hinges, shoulder ROM screens etc.  You have to have a deep rooted fundamental knowledge of the gait central processing and gait parameters. If you do not, every other screen that you put your athlete or patient through might have limited or false leading meaning. 

Shawn and Ivo …  combining 40 years of orthopedics, neurology, biomechanics and gait studies to get to the bottom of things.

Hip function and knee pain, again.

And once again…… another study validating the fact of weak hip stabilizing muscles in causing knee pain.  The study showed that increased activation of the gluteus maximus in individuals with patellofemoral knee pain suggests that these subjects were attempting to recruit a weakened muscle, perhaps in an effort to stabilize the hip joint.

J Orthop Sports Phys Ther. 2009 Jan;39(1):12-9.

Differences in hip kinematics, muscle strength, and muscle activation between subjects with and without patellofemoral pain.

Souza RB, Powers CM.


Department of Radiology and Biomedical Imaging, University of California, San Francisco, CA, USA.

Hip rotation and knee pain. What we have been saying.

We have been pounding the floor on this topic on and off for the last 6 months it seems.  Lack of internal hip rotation or too much internal hip rotation ……. both abnormal hip kinematics, is a result of reduced hip-muscle performance as opposed to structural issues of the hip (anteversion, retroversion etc).

If you are not assessing for impaired hip muscle function in your knee patients, you could be missing the boat …….. and it is a big boat…… Titanic in size.

Don’t be like so many others and be tunnel visioned when you have a knee patient, expand your vision, at least to the hip and foot. 

We are……. The Gait Guys……. Shawn and Ivo


Am J Sports Med. 2009 Mar;37(3):579-87. Epub 2008 Dec 19.

Predictors of hip internal rotation during running: an evaluation of hip strength and femoral structure in women with and without patellofemoral pain.

Souza RB, Powers CM.

Musculoskeletal and Quantitative Imaging Research Laboratory, Department of Radiology and Biomedical Engineering, University of California, San Francisco, California, USA.

Why Runners need to take a page out of their automobile maintenance manual when it comes to running injury prevention.

Tissues have limits. They are like a tire, they only have so much tread on them before they show pathology. But like a tire, it takes time for a wear pattern to show up enough to make the tire wobble or the axle to pull the car mildly towards the ditch.  Take a spinal disc, it has a certain number of compression and load cycles before it begins to desiccate, especially in the higher load / transition zones of the spine.  Cartilage has a certain number of cycles before it begins to desiccate and crack/fissure and flake.  Osteoarthritis then begins its slow sneaky onset.  Tendons and ligaments have the same “limited lifespan” especially if loaded imperfectly with strained joint loads.  Just because someone is pain free doesn’t mean they are safe. The abnormal load on an ITB band doesn’t begin the moment that pain presents itself.  The problem brews in the background long before there is pain. Pain and injury represent a failure point in the mechanism.  At this point it is too late.  Being in medicine, we would be just like all the others if we crisis managed every athlete that walks in the door.  So, we are in the game of prevention. We know our biomechanics, we know our orthopedics, physiology and neurology as good as the best out there. And so , we are well positioned on the front lines to identify problems before they ensue, and pick up on that aberrant wear pattern on the proverbial “tire” long before the pattern of wear is so bad that an injury is immanent and a foregone conclusion.  So, this bodes the bigger question, just because you are injury free for many marathons and decades, doesn’t mean you shouldn’t take your car in , have its tires rotated, lug nuts snugged up, and alignment tweaked so that  your car’s life will be maximized.  Remember, unlike a car, we get one set of tires. We cannot replace bolts, we cannot remove the rust or put in a new oil or air filter. All we can do it make sure our “car” , our body, is working as best it can with the anatomical parts it has. 

We do not think anyone would disagree that leaving alone and ignoring a 99% stenosed artery in the heart’s “widow maker” artery is a good idea just because someone hasn’t had a heart attack yet.  Checking the body for malfunction early can prevent some unpleasant problems down the road.  Pain or tightness is the dashboard’s “check engine” light.  Regular check ups should keep that light off and reduce the sudden anxiety that comes when it turns on. 

In summary, we take our cars in for tune up maintenance 2-3 times a year. And usually we drive away without the car driving too much different.  But, we are at ease knowing it is in tip top shape and can go another 6000 miles before it might show signs of wear.  We should do the same with our body and our gait mechanics and fix and change the little things that are sneaking up on us that could trigger that “check engine” light.  By the time it comes on, it could be too late and require major repairs which just might keep your “car” off the road for awhile while repairs are made.  No one likes to hear from the mechanic, “well Mr. Jones…….if we had checked up on this earlier before it was a big problem, we could have prevented this expensive set back on the sidelines.”

Our bottom line,  even if your running is pain and injury free for years on end (which would make you a rare bird as runners go), it should make sense to you that improving biomechanical deficiencies isn’t likely a bad thing for the long term. Rather, it is probably the smartest of choices to keep you on your journey down the road, around the next bend, one efficient step after another.

“An ounce of prevention is worth a pound of cure”. -Ben Franklin

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A Case of Hip pain in a Young Runner: Perthes Disease

here is a nice little short video of a young girl with a healed Perthe’s Disease (full name, Legg-Calve-Perthes Disease) that came to see us a few years ago with right hip pain.  After an examination and a very brief treatment stint films were obtained and found an early stage Perthe’s Hip.  Early diagnosis is always important in this disorder that affects the vascularity of the head of the femur. Failure to make an early diagnosis is a disaster which leads to deformity and permanent disability for the patient.  Perthe’s affects mostly male boys under the age of 10. There is really no clear etiology but many studies point to a period of increased pressure within the joint from an inflammatory process. A term “Transient Synovitis” has been labeled by some.  In this case, the disorder was caught in its first stage and the hip revascularized, did not collapse and it is doing well.  Collapse is the most devastating outcome of this disease process, it is why you do not mess around with children with unresolving hip pain, obtain imaging early.  The main problem, as is seen here, is that she cannot get to her gluteal muscles to stablize the hip in the frontal plane.  Here you see a classic Trendelenberg Sign when she steps onto the right leg. 

When she steps onto the left hip the hip,knee and foot are well aligned in the frontal plane and the right hemipelvis rises above the left hip joint line.  Comparatively, when she steps on the right, there is a significant lateral pelvic and body mass shift beyond a line drawn up from the foot-knee line.  Consequently the left hip drops and she looks like she has a short right leg.  Measurements (as unreliable as they are)  do not show a leg length discrepancy.  However, this type of mechanical behavior can put undue stress on a healing femoral head.  Using a sole lift to help regain pelvic leveling during gait help maintain balanced femoral head pressures and cartilage coverage during the last stages of joint formation in this adolescent.  The problem is that there will be dependency on the lift so regular daily exercises with guaranteed compliance is imperative.  She must regain use of the glute in gait and stance or this hip will be a problem in later years, guaranteed.  So, this is a difficult case.  It is not for the faint of heart.  Bottom line, do not mess with kids with hip pain for long without imaging to rule out terrible problems like this.  There are so many gait problems that will ensue if the gluteal stability is not regained.  To name just a few, the right foot will always be supinated and this means risk for bunions (see last weeks Dr. Ivo video on bunions and the adductor hallucis muscle) and other disorders that are caused by an unanchored first metatarsal.  Additionally, the knee can degenerate the lateral compartment quickly not to mention the plethora of muscular problems (low back pain, knee pain etc) and strategies (ie. pelvic distortion patterns) that will ensue from such a gait.  There is so much more to Perthes Disease than we have mentioned here, but this is not the venue for such complicated topics.  The important thing is to beware of systemic problems that can compromise the integrity of the neuromusculoskeletal system that can have short and long term effects on one’s gait. Here is a link to some more info on Perthes Disease …… but even this is scant info (….. make sure you do your reading if you are in the clinical world and see young patients. 

It is not always just about muscles and shoes and orthotics. You have to always be on your toes (no pun intended).

we are…….. so much more…….. than just Gait Guys.

Biomechanical and Clinical Factors Related to Stage I Posterior Tibial Tendon Dysfunction.     Rabbito M, Pohl MB, Humble N, Ferber R.


The increased foot pronation is hypothesized to place greater strain on the posterior tibialis muscle, which may partially explain the progressive nature of this condition. J Orthop Sports Phys Ther, Epub 12 July 2011. doi:10.2519/jospt.2011.3545.


What the Gait Guys say about this article:

Do these results really surprise us? The Tibialis posterior (TP) is one of the more important extrinsic arch stabilizing muscles. It is a stance phase muscle that fires from the loading response through terminal stance. It ‘s proximal attachments are from the posterior aspect of the tibia, fibula and interosseous membrane and its distal attachments are the undersurface of all the tarsal’s except the talus and the bases of all the metatarsals except the first.

Since the foot is usually planted when it fires, we must look at its closed chain function (how does it function when the foot/insertion is fixed on the ground), which is predominantly maintenance of the medial longitudinal arch, with minor contributions to the transverse metatarsal and lateral longitudinal arches; flexion and adduction of the tarsal’s and metatarsals, eccentric slowing of anterior translation of the tibia during ankle rocker. It is also an external rotator of the lower leg and is the prime muscle which decelerates internal rotation of the tibia and pronation. As the origin and insertion are concentrically brought towards each other during early passive heel lift it becomes a powerful plantarflexor and inverter of the rearfoot.  There is also a  component of ankle stabilization via posterior compression of the tarsal’s and adduction of the tibia and fibula.

Alas, there is soooo much more than the typical open chain function of plantar flexion, adduction and inversion. Perhaps it is some of these other, closed chain functions, that cause the “progressive nature of the condition”?

We remain…The Gait Guys…Going above and beyond basic function and biomechanics.