Gait and Climbing: Part 1

Lucid Dreaming is the name of a rock in the Buttermilks of Bishop, California. This is no ordinary rock. It is a V15. Summiting this rock is basically only 3 moves off of 3 holds, from your fingertips. The remainder of the climb is sliced bread. If you can do the 3, you can get to the top. The problem is, only a handful of people in the world can do it. How hard can this be, after all you start sitting down.

Strength, stability, mobility, endurance, skill, experience, movement patterns … . it is all here, today, on The Gait Guys blog.

Author: Dr. Shawn Allen

There are things that other people can do in life that rattle your brain. These are tasks that these individuals make look fairly simple, but in actuality are nearly impossible to the average person.  The honest fact is that many of us could do many of these things to a degree if we would dedicate a portion of our day to building the engine to perform these tasks, but the truth is that many of us would rather sit down and be entertained than get up and struggle.

Here on The Gait Guys blog, bipedal and quadrupedal gait has been discussed for over 5 years. Discussions have gone deep into the strange quadrupedal gait of Uner Tan Syndrome and have delved into the critical neurology behind CPG’s (Central Pattern Generators) which are neural networks that produce rhythmic patterned outputs. We have gone on and on about arm swing and how they are coordinated with the legs and opposite limb in a strategic fashion during walking running gaits.

Today I will look briefly at the interconnected arm and leg function in a high functioning human arguably one of the best new hot shots in climbing, Alex Megos. This year the German, as seen in this video link today, managed to summit Lucid Dreaming, a V15 in the Buttermilks of Bishop, California. Hell, you can say that this is just a big boulder, but there are not many V15s in the world like this one. Only a few of the very best in the world have even tried this rock, and you can count even fewer who have reached the summit. So, what does V15 mean to you? “virtually impossible” just about sums it up. Watch the video, this V15 starts from a “sit-start”, many folks wouldn’t even get their butts off the ground to complete the first move, that is how hard this is.  Watch the video, if this does not cramp your brain, you perhaps you don’t have one.

Are there possible neurologic differences in climbers such as Megos as compared to other quadruped species?  Primarily, there is suspect of an existing shift in the central pattern generators because of the extraordinary demand on pseudo-quadrupedal gait of climbing because of the demand on the upper limbs and their motorneuron pools to mobilize the organism up the mountain. We know these quadrupedal circuits exist. In 2005 Shapiro and Raichien wrote “the present work showed that human QL(quadrupedal locomotion) may spontaneously occur in humans with an unimpaired brain, probably using the ancestral locomotor networks for the diagonal sequence preserved for about the last 400 million years.”

As we all know, the interlimb coordination in climbing and crawling biomechanics shares similar features to other quadrupeds, both primate and non-primate, because of similarities in our central pattern generators (CPG’s). New research has however determined that the spaciotemportal patterns of spinal cord activity that helps to mediate and coordinate arm and leg function both centrally, and on a cord mediated level, significantly differ between the quadruped and bipedal gaits. In correlation to climbers such as Megos however, we need to keep in mind that the quadrupedal demands of a climber (vertical) vastly differ in some respects to those of a non-vertical quadrupedal gait such as in primates, in those with Uner Tan Syndrome and during our “bear crawl” challenges in our gyms. This should be obvious to the observer in the difference in quadrupedal “push-pull” that a climber uses and the center-of-mass (COM) differences.  To be more specific, a climber must reduce fall risk by attempting to keep the COM within the 4 limbs while remaining close to the same surface plane as the hands and feet (mountain) while a primate,  human or Uner Tan person will choose  to “tent up” the pelvis and spine from the surface of contact which narrows the spreading of the 4 contact points. Naturally, this “tenting up” can be reduced, but the exercise becomes infinitely more difficult, to the point that most cannot quadrupedally ambulate more than a very short distance. I will discuss this concept in Part 2 of this series on climbing.  If you study childhood development and crawling patterns, you need to be familiar with UTS (search our blog, save yourself the time), the flaws in the neurology behind the "Bird Dog” rehab pattern, and crawling mechanics … and of course, study climbers.

Some research has determined is that in quadrupeds the lower limbs displayed reduced orientation yet increased ranges of kinematic coordination in alternative patterns such as diagonal and lateral coordination.  This was clearly different to the typical kinematics that are employed in upright bipedal locomotion. Furthermore, in skilled mountain climbers, these lateral and diagonal patterns are clearly more developed than in study controls largely due to repeated challenges and subsequent adaptive changes to these lateral and diagonal patterns.  What this seems to suggest is that there is a different demand and tax on the CPG’s and cord mediated neuromechanics moving from bipedal to quadrupedal locomotion. There seemed to be both advantages and disadvantages to both locomotion styles. Moving towards a more upright bipedal style of locomotion shows an increase in the lower spine (sacral motor pool) activity because of the increased and different demands on the musculature however at the potential cost to losing some of the skills and advantages of the lateral and diagonal quadrupedal skills.  Naturally, different CPG reorganization is necessary moving towards bipedalism because of these different weight bearing demands on the lower limbs but also due to the change from weight bearing upper limbs to more mobile upper limbs free to not only optimize the speed of bipedalism but also to enable the function of carrying objects during locomotion.

The take home seems to suggest that gait retraining is necessary as is the development of proper early crawling and progressive quadruped locomotor patterns. Both will tax different motor pools within the spine and thus different central pattern generators (CPG). A orchestration of both seems to possibly offer the highest rewards and thus not only should crawling be a part of rehab and training but so should forward, lateral and diagonal pattern quadrupedal movements, on varying inclines for optimal benefits.  Certainly I need to do more work on this topic, the research is out there, but correlating the quad and bipedal is limited. I will keep you posted. Be sure to read my 3 part series on Uner Tan Syndrome, here on The Gait Guys blog. Some of today’s blog is rehash of my older writings, naturally I am setting the stage for “Part 2″ of Climbing.

– Dr. Shawn Allen

 References:

Shapiro L. J., Raichien D. A. (2005). Lateral sequence walking in infant papio cynocephalus: implications for the evolution of diagonal sequence walking in primates. Am. J. Phys. Anthropol.126, 205–213 10.1002/ajpa.20049

Scand J Med Sci Sports. 2011 Oct;21(5):688-99. Idiosyncratic control of the center of mass in expert climbers. Zampagni ML , Brigadoi SSchena FTosi PIvanenko YP

J Neurophysiol. 2012 Jan;107(1):114-25. Features of hand-foot crawling behavior in human adults. Maclellan MJ, Ivanenko YP, Cappellini G, Sylos Labini F, Lacquaniti F.

The hand walkers: The family that walks on all fours. Part 1

Quadrupedalism and its commentary on human gait.  To understand your athlete, your patient, your client, whatever your profession, you need to have a good understanding of neurodevelopment.  If your client has some functional movement pattern flaws it could be from a delayed or expedited neurodevelopmental window. Generalized training and rehab will not correct an early or late window issue; often your work must be more specific.

     When we began our journey into our daily writings on “The Gait Guys blog” we had no idea of the never ending tangents our writing would take pertaining to gait, human movement and locomotion. It has become plainly obvious over time that this blog will likely exist as long as we choose to continue it. 

In 2006 we saw a documentary documentary entitled The Family That Walks On All Fours and the video clip above was from the documentary. It was a fascinating documentary and with our backgrounds in neurology, neurobiology, neuroscience, biomechanics and orthopedics we had more questions than the documentary touched upon. The documentary opened up many thoughts of neuro-development since we all start with a quadrupedal gait. But there had to be more to it than just this aspect because people eventually move through that neurologic window of development into bipedial gait.  This has been in the back of our minds for many years now.  Today we will touch upon this family and their challenges in moving through life, today we talk about Uner Tan syndrome, Unertan syndrome or UTS.

The original story is about the Ulas family of nineteen from rural southern Turkey. Tan described five members as walking with a quadrupedal gait using their feet and the palms of their hands as seen in this video.  The affected family members were also severely mentally retarded and displayed very primitive speech and communication. Since his initial discovery several other families from other remote Turkish villages have also been discovered.  In all the affected individuals dynamic balance was impaired during upright walking, and they habitually chose walking on all four extremities. Tan proposed that these are symptoms of Uner Tan syndrome.

UTS is a syndrome proposed by the Turkish evolutionary biologist Uner Tan. Persons affected by this syndrome walk with a quadrupedal locomotion and are afflicted with primitive speech, habitual quadrupedalism, impaired intelligence. Tan postulated that this is a plausible example of “backward evolution”. MRI brain scans showed changes in cerebellar development which you should know after a year of our blog reading means that balance and motor programming might be thus impaired.  PET scans showed a decreased glucose metabolic activity in the cerebellum, vermis and, to a lesser extent the cerebral cortex in the majority of the patients. All of the families assessed had consanguineous marriages in their lineage suggesting autosomal recessive transmission. The syndrome was genetically heterogeneous.  Since the initial discoveries more cases have been found, and these exhibit facultative quadrupedal locomotion, and in one case, late childhood onset. It has been suggested that the human quadrupedalism may, at least, be a phenotypic example of reverse evolution.

Neurodevelopment of Children:

Children typically go through predictable windows of neurodevelopment. Within a set time frame they should move from supine to rolling over. Then from prone they should learn to press up into a push up type posturing which sets up the spine, core and lower limbs to initiate the leg movements for crawling. Once crawling ensues then eventual standing and cruising follow.  In some children, it is rare yet still not neurodevelopmentally abnormal, they move into a “bear crawl” type of locomotion where weight is born on the hands and feet (just as in our video today of UTS).  Sometimes this window comes before bipedalism and sometimes afterwards but it should remain a short lived window that is progressed through as bipedalism becomes more skilled. 

In studying Uner Tan Syndrome, Nicholas Humphrey, John Skoyles, and Roger Keynes have argued that their gait is due to two rare phenomena coming together.

“First, instead of initially crawling as infants on their knees, they started off learning to move around with a “bear crawl” on their feet.Second, due to their congenital brain impairment, they found balancing on two legs difficult.Because of this, their motor development was channeled into turning their bear crawl into a substitute for bipedalism.”

According to Tan in Open Neurol, 2010

It has been suggested that the human quadrupedalism may, at least, be a phenotypic example of reverse evolution. From the viewpoint of dynamic systems theory, it was concluded there may not be a single factor that predetermines human quadrupedalism in Uner Tan syndrome, but that it may involve self-organization, brain plasticity, and rewiring, from the many decentralized and local interactions among neuronal, genetic, and environmental subsystems.

There is much more we want to talk about on this mysterious syndrome and the tangents and ideas that come from it. We will do so in the coming weeks as we return to this case.  We will talk about other aspects of neurodevelopment which should be interesting to you all since most our readers either are having children, will have them, or are watching them move through these neurologic windows.  And we know that some of our readers are in the fields of therapy and medicine so this should reignite some thoughts of old and new.  In future posts we will talk about cross crawl patterning in the brain, bear crawling, the use of the extensor muscles in upright posture and gait as well as other aspects of neurodevelopment gone wrong. We are not even close to being done with this video and all of its tangents. In the weeks to come we hope you will remain interested and excited to read more about its deep implications into normal and abnormal human gait.

References:

Open Neurol J. 2010 Jul 16;4:78-89. Uner tan syndrome: history, clinical evaluations, genetics, and the dynamics of human quadrupedalism. Tan U.Department of Physiology, Çukurova University, Medical School, 01330 Adana, Turkey. link: http://www.ncbi.nlm.nih.gov/pubmed/21258577

Humphrey, N., Keynes, R. & Skoyles, J. R. (2005). “Hand-walkers: five siblings who never stood up” (PDF). Discussion Paper. London, UK: Centre for Philosophy of Natural and Social Science.

http://informahealthcare.com/doi/abs/10.1080/00207450701667857

http://informahealthcare.com/doi/abs/10.1080/00207450500455330

http://www.ncbi.nlm.nih.gov/pubmed?term=Uner%20Tan%20syndrome