The Gait Guys

The Hand Walkers, Part 2. Uner Tan Syndrome, the new research.

A year ago we wrote our first piece on Uner Tan Syndrome. We have always been interested in the neurodevelopmental windows of children and their process of moving through the various movement phases in the hopes of gaining clean upright bipedal gait. In our clinics daily we see many soft signs of sensory-motor pattern aberrancies that result in foot problems such as lack of pronatory control, or torsional long bone abnormalities and failures to protect frontal plane deviations (to name a very small few). In fact, these soft seonsory-motor signs and patterns can be found globally if one knows what to look for. In our clinics we rarely see the serious neuro-developmental problems but Uner Tan Syndrome (UTS) has always been one of interest to us. We recently received a very kind email from Turkey, from Dr. Uner Tan himself, asking to reference some of our work so this was a serious honor. The email sparked us to look into his research to look for newer work and we were happy to find it. Before we start into the new research findings, you will want to take a few minutes to read our last blog piece on Uner Tan Syndrome: The Hand Walkers.

http://thegaitguys.tumblr.com/post/28332726553/the-hand-walkers-the-family-that-walks-on-all

This previous blog post discussed much of the research that was current at the time. The following was from our previous blog post on UTS

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.

However, some startling new research has recently surfaced and if most are paying attention, they will see the value in our 1000+ blog posts here at The Gait Guys but more so discover Dr. Tan’s most startling conclusion from the Frontiers in Neurology article below. We are currently moving through the most recent research so you will want to check in with us again soon for our follow up blog posts on this topic.

Here was Dr. Tan’s et al abstract conclusion of his most recent research, and we think it is earth shattering.

Human quadrupedalism is not an epiphenomenon caused by neurodevelopmental malformation and ataxia.

Two cases with quadrupedal locomotion (QL) were presented. In both cases, cognitive and psychiatric functions were normal and, no neurological deficits were observed, except for a sequel paralysis of left leg in Case 2. It was suggested that human QL (1) should not be considered as an epiphenomenon caused by neurodevelopmental malformation and ataxia, but (2) may be considered as a re-emergence of the ancestral diagonal QL, and (3) it may spontaneously emerge in humans with entirely normal brains, by taking advantage of neural networks such as central pattern generators that have been preserved for about 400 million years.

We will have more to come shortly, but for now, realizing that the human brain, even when normal, can take advantage of neural networks encompassing Central Pattern Generators (CPG’s) that have been suppressed for 400 million years is startling information in our opinion.

Check back in with us soon.

Dr. Shawn Allen, one of the gait guys

References:

Front Neurol. 2012 Oct 25;3:154. doi: 10.3389/fneur.2012.00154. eCollection 2012. Karaca S1, Tan M, Tan U. Human quadrupedalism is not an epiphenomenon caused by neurodevelopmental malformation and ataxia.

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.

author: Dr. Shawn Allen, one of the gait guys

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.