Muybridge: Art, Motion and Biomechanics (repost 8/2010)

Edweard Muybridge visited the Corcoran Gallery of Art in 1887 to personally make a presentation of his eleven volume “Illustrations of Animal Locomotion”. They later purchased the text. An exhibition titled “Helios: Eadweard Muybridge in a Time of Change”  at the Corcoran displaying Muybridge’s groundbreaking photography and motion studies has just concluded. I had the joy of spending a few hours at the exhibit in close study. As an added and unrelated bonus I was also able to see a new exhibit on the artist Chuck Close.

Artists and scientists have long had an interest in human anatomy and motion. Over the last 50 years, movement and gait have been analyzed using gait plates, computer force distribution systems, electromyogram (EMG) and video. When, where and how did modern analytic methods develop? What was their antecedent? Most textbooks and articles are skimpy at best about much of the early history of the study of locomotion and movement.

The science of  biomechanics has forgotten about the 19th century developments that made for rapid progress in the last 100 years. The historical memories of biomechanics seem to start in the 20th century with Morton’s observations, and Elftman, Inman and Mann’s theories. Artists, however, remember Muybridge,  and going further back, it is clear that Michelangelo was deeply interested in anatomy and Leonardo (performed dissections and) wanted to know how everything worked. Along the way to the present, many other artists and scientists studied and observed animal and human movement. But until the late 19th century there was no technology available to capture data and information of movement.

Edweard Muybridge  (1830-1904) was the first to systematically develop equipment and techniques to photograph the movement of quadripedal and bipedal gait along with a variety of other movements, motions, and human athletic activities.  In 1877 Muybridge was hired by Leland Stanford to demonstrate that all 4 limbs were off the ground at one point during the trotting gait of a horse. Muybridge developed an automatically triggering electronic shutter. In 1878, Muybridge hooked up a series of about a dozen cameras to automatically and sequentially fire and record the gait of a horse.  While exposures at that time were often several minutes long, the 12 exposures occurred over about half a second.  A highly contrasting, light background was designed to enhance the image. A numbering system was used which gave positional and, indirectly, timing information. Stanford ultimately won his bet and was able to use Muybridge’s photographs to demonstrate that all of the horses feet left the ground during a trot.

Out of the studies of motion that Muybridge did came several breakthroughs that were noted by Rebecca Solnit in “River of Shadows”.

1)   An electronic automatically triggered shutter, which Muybridge felt would revolutionize photography.

2)   Advances in plates and development which could capture movement and allowed for capture of an image in less time than anyone had accomplished previously.

3)   Capturing of several images that could be mounted together to represent a cycle of motion (such as a gait cycle) rather than a single isolated moment.

4)   The possibility of sequencing and showing an image sequence as a moving picture to reanimate the movement as a moving picture.

The first and second breakthroughs were accomplished in 1877, the other breakthroughs came in 1878 and 1879. It took celluloid and other much later developments to bring a motion picture industry to life. But both the methodical study of movement and a film industry had their beginnings with the work of Muybridge.

Early technology was so bad that images were often barely discernable and had to be painted in. In some cases the images were filled in and then re-photographed by Muybridge. (The equivalent of photoshopping your work today.) Ultimately, however, Muybridge recorded many sequences of activity making up  about 11 volumes. The complete set of volumes was sold to the Corcoran museum in Washington, DC in the 1890’s for $600.

Stanford published a text on the movement of animals , while Muybridge was lecturing in England and employed by a professional society. Many images drawn after Muybridge’s plates and several of his images were used while the text gave Muybridge no credit for the work.

Muybridge’s work has often been discounted as merely “art”, but it was an important qualitative look at movement. Diagrams in modern texts detailing varieties of normal and abnormal gait look like they were sketched from his plates or photographed using methods similar to his. He influenced many artists, worked with Thomas Eakins and inspired Marcel Duchamp to paint “Nude Descending A Staircase“. Clearly there is inspiration, emotion, and art in his work, but using the scientific analysis and invention he was at the forefront in creating techniques that were later used to quantify motion and gait analysis. His text “Animals In Motion” has long been used by illustrators to draw sequences which when put together will stream as a moving animal. His work had great impact on animation and led to the development of film. Look for more details on Muybridge on my main website in the near future.

The Helios exhibit will next be seen at the Tate Britain in London from September 8, 2010 through January 16, 2011, and will finish at the San Francisco Museum of Modern Art from February 26 through June 7, 2011.


River of Shadows: Eadweard Muybridge and the Technological Wild West. Penguin Books. 2003.

Helios: Eadweard Muybridge in a Time of Change. Philip Brookman. Corcoran Gallery of Art. 2010. (Exhibit and Catalog)

Picturing Time: The Work of Etienne Jules Marey. Marta Braun. University of Chicago Press: 1992.

Boxing - Muybridge Study
Boxing – Muybridge Study

Running Sports Medicine Tendinopathy

Achilles Tendinopathy: 2010 – Disappointing Results with PRP (repost from 01/2010)

Update: The results are still controversial and contradictory on PRP and Achilles tendinopathy. This is a repost of a blog from 2010. (The primary reason for the repost is moving material of archival interest to a site which functions better.)

A study published in the Journal of the American Medical Association, Jan. 13, 2010 gave disappointing results in using plasma rich protein to treat non-insertional Achilles tendinopathy. It showed no difference between using a sham injection of saline and combining it with a painful eccentric stretching protocol  in comparison with an injection of plasma rich protein injection along with the standard painful eccentric stretching protocol.

The authors note that previous studies did not have good control groups. In this small study, 27 patients were in the placebo group and 27 in the treatment group. The VISA-A score was used to assess improvement. Both groups improved somewhat without a significant difference between the two groups.

The study was called a “preliminary communication” which is often done with small studies. Other studies on similar topics with fewer than 30 individuals studies have also been billed as “preliminary studies”, but when they are talked up afterward, the “preliminary study” status is usually forgotten. As far as study design goes, the design, blinding, and performance of the study seems just right. I am not entirely convinced of the efficacy of the painful eccentric stretching protocol and would have not minded another study group omitting that treatment. Apparently it is not a panacea (or there would not be studies looking to add to the results), although the initial preliminary study made it sound as though it would be. Follow up journal articles by the primary author of the first study have been positive and are referenced below. Others have expressed reservations on the methodology. (see Woodley et. al. 2007 and Kingma et. al. 2006) Eccentric stretching and overload for tendinopathy has mixed results at best in other body areas.

Note: VISA-A is the Victorian Institute of Sports Assessment-Achilles


Platelet-Rich Plasma Injection for Chronic Achilles Tendinopathy: A Randomized Controlled Trial
Robert J. de Vos; Adam Weir; Hans T. M. van Schie; et al. JAMA. 2010;303(2):144-149 (doi:10.1001/jama.2009.1986)

Alfredson H. Chronic midportion Achilles tendinopathy: an update on research and treatment. Clin Sports Med. 2003;22(4):727-741.

Alfredson H and Cook J (2007), A treatment algorithm for managing Achilles tendinopathy, new treatment options, British Journal of Sports Medicine, 41, 4, 211.

J J Kingma, R de Knikker, H M Wittink, T Takken. Eccentric overload training in patients with chronic Achilles tendinopathy: a systematic review. Br J Sports Med 2007;41:e3 ( doi: 10.1136/bjsm.2006.030916 (concludes: Studies on the effectiveness of eccentric overload training in patients with Achilles tendinopathy show many methodological shortcomings)

Woodley, B.L., R.J. Newsham- West, and D.B. Baxter, Chronic tendinopathy: effectiveness of eccentric exercise. Br J Sports Med, 2007. 41: p. 188-199.

Additional Information:

Pribut, S.M.,  Top 5 Running Injuries. Podiatry Management, 2008

Blog on: Heel Lifts and Achilles Tendinitis

Dr. Pribut on Achilles Tendinopathy

Dr. Pribut on The Science of Tendinopathy


Steve Jobs Leaves Apple: End Of An Era (repost 8/2011)

You may love Apple computers and their devices including the iPod, iPad, and iPhone. Or you may like Windows computers or perhaps Linux boxes. Whatever you like about your computer, whatever it may be, it was Steve Jobs and

Apple - The Rainbow
Apple - The Rainbow

Steve Wozniak’s abilities, vision, and salesmanship that has put one in your home.

Without Wozniak the engineer, and Jobs the guy with the vision, your computer would weigh half a ton and probably only be at your office. Back in the Homebrew Computer years the vision of a home computer was something that could display lights which if you could decode the binary message you would know the answer to 2 + 2. Bill Gates during those Homebrew years came up with the bright idea of selling and owning software starting with Basic. Not long after – it was licensing rather than owning software.

But Jobs had an idea that a computer could be more, and could be in many houses, not only in the homes of those who read Popular Electronics. IBM jumped on the bandwagon, but did not consider their PC market particularly important for several years. The hype in those early days made it difficult to determine what was going to be the best machine for business purposes. In those early years it was clear that IBM and DOS was more suitable for business rather than the Apple II. But still, it was Jobs that forced IBM’s hand to even making those smaller machines. Gates was clever enough to license both a DOS (disk operating system) and a Basic interpreter to

Altair with Cool Lights
Altair with Cool Lights

more than one computer manufacturer. He escaped an exclusive arrangement with IBM and every other hardware manufacturer that he dealt with.

In 1979 Jobs visited Xerox PARC and liked what he saw. He came away with the idea of creating a graphic user interface, a mouse for data input, fonts, an improved menu system, and an overall friendlier computer system.
Out of this came the overpriced and failed Lisa and the game changing Macintosh. With the advent of the graphic user interface, Gates saw that DOS had a finite life and worked on Windows. The first widely distributed Windows Beta showed it’s gaming strengths which led from Reversi to Solitaire. And later to Doom, Quake and Warcraft. OS X is still not a gaming platform, although a speedy iMac can run a number of game programs quite well.

Not long after the development of the Mac, the dapper soda pop expert, hired by Jobs as CEO, boasted he did not have a computer on his desk. He proceeded to force Steve Jobs out of his company. Steve Jobs then founded NEXT and purchased PIXAR which no one had a clue would ever amount to anything.


As Apple appeared headed to certain failure, Jobs returned as CEO and the operating system of NEXT grew into OS X. With innovations in portable devices in addition to a solid, crash “lite” operating system, Apple met with considerable success. Jobs always asked the near impossible of his engineers and designers. Smaller and smaller, thinner and thinner all things became. The Titanium Macbook Pro was the first Apple computer I used. Being less than 1 inch thick, with the first DVD drive, and OS X, which is an attractive shell over what is mostly BSD UNIX attracted me (after finding that I liked Linux as an alternative to dealing with the faults, flaws, and security weaknesses of Windows.) Using Intel processors brought Apple a long way and the ability to run Windows on the same machine was welcomed by many. Personally, I’ve decided I like my windows on it’s own machine.

The iPod changed the way we listen to music. In many ways the convenience is for the better. But in deference to the music geeks, I’ll admit that we find ourselves in a “low-fi” world. With the loss of the ability to hear all of the high tones, it matters less to me right now. After giving in to reason, allowing video on the small device was a big plus. The iPhone was a bold step and did work quite well the first day right out of the box. A fine interface, an attractive device, an interesting combination of apps that worked well was a different model than other companies had used. Yes, it was certainly and still is a relatively restrictive environment, closed, not user friendly to jailbreak and less friendly after being jail broken. But the trade off has been a reliable and fun to use device. The iPad is a good size for many older people and has caught on well as a tablet. It has caught on so well, that others, such as H-P have even given up trying to compete.

Starting with putting a friendlier face on computing and the concept of computers for everyone, Jobs thought different. Interface and design intersected in ways not before conceived of in the computing world. Computers, email, face-to-face communication via your cell phone or computer, ease of access to information, research, music, and software have changed the landscape of the world. Jobs played a role in this, as did many others. But I give Steve Jobs much credit for the role he played.

Since Jobs developed  pancreatic cancer, which is often deadly within a year or so, and later had a liver transplant, his health has been shaky. Somehow he has still managed to bring enthusiasm and new products regularly to Apple. A biography of Jobs written by Walter Isaacson was originally scheduled to be published in March, 2012 and was to be called iSteve: The Book of Jobs. Publication has been moved up to November, 2011 and the title is now the more serious “Steve Jobs: A Biography”. I didn’t take that as a good sign.

I’m not sure what Apple will be like after Jobs. I’m sure it will be a solid company and will continue to be competitive. But, it will miss the driving vision and uncompromising principles of Jobs. The engineers will be able to relax a bit, but I’m sure the next 15 years will be much different than they would be in the absence of a healthy, strong, and visionary Steve Jobs at the helm. I send thanks and wish Steve Jobs well and as pleasant a transition as possible.


Who was Pheidippides?

All marathons are special. You’ll remember your first marathon and your last one for a long, long time. And you may have favorites of the ones in the middle. But, what’s the story on the first marathon ever run. The 2,500 year Anniversary run is coming up on October 31, the same day as the Marine Corps Marathon here in D.C. Did the first marathoner die or is that a story?

Who was Pheidippides? Amby Burfoot does the research, tells us, and plans for a historic marathon. Amby’s writing can’t be beat and he covers this thoroughly.

The photos in this article alone are worth a look.

Biology Culture Sports Medicine

Testosterone: Epitestosterone Ratio: Cheating or Genes?

(repost from 01/2011)

The Case Against Lance Armstrong” is the title of an article in the January 24, 2011 issue of Sports Illustrated. The case that is made within this article is based on in large part on what a few people with gripes against Lance have said. The other “hard” evidence is based on several tests detailing a very high Testosterone:Epitestosterone ratio. Before 2005 the tests normal was considered up to 6:1 and was then lowered to 4:1. Several tests over the years, which may have been Lance’s were considerably higher than this.

According to SI “Three results stand out: a 9.0-to-1 ratio from a sample collected on June 23, 1993; a 7.6-to-1 from July 7, 1994; and a 6.5-to-1 from June 4, 1996.”

Each time the ratio was found to be high, the “B” Sample was tested and found to not confirm the preliminary test. The second test is usually a carbon isotope test that is more specific to studying the makeup of the individual’s testosterone.

While the article goes on to say that one high number (of the T:E ratio) should be a once in a blue moon occurrence, there are significant genetic factors that can come into play.  A 2008 article published in The Journal of Clinical Endocrinology & Metabolism titled “Doping Test Results Dependent on Genotype of UGT2B17, the Major Enzyme for Testosterone Glucuronidationshowed that if an individual had two alleles for the UGT2B17 gene, there was a large chance that they would not test positive for cheating even after having taken a large dose of synthetic testosterone. The estimates were that 40% of individuals could pass the ratio examination just by virtue of having two copies of this gene. On the other hand with mixed alleles (ins/del) or in the absence of  this allele there was a fair chance that the ratio would always be abnormal. Estimates were that in a normal population, up to 9-14% of people would have a false positive result and fail the test.

It seems that if you have the del/del or ins/del variations of alleles, you are going to pretty consistently fail the test. The authors suggest that this gene should be tested and the results modified based upon the genotype of the individual.

Understanding the purpose of the Testosterone:Epitestosterone ratio testing and doing at least a brief look at  factors that might affect this test, not just once but repeatedly are important when an article such as the SI one is written. This specific gene and its implication on testing is widely known and has been covered in a variety of journal articles. The Canadian Medical Journal detailed, in an editorial titled “Doping, Sport, and the Community“, the difficulties in testing for Growth Hormone abuse and Testosterone. The editorial also mentioned research I came across elsewhere which indicated that many Asians (up to 40%) had the version of this gene that would give a false negative.

So, let’s get all the evidence out. And let’s make sure the public sees all the scientific information on the validity and the problems that exist with this particular test. For another perspective on heroes in American culture, you can seek out one of George Carlin’s last specials in which he expresses his opinion on hero worship and in particular on Lance Armstrong, Tiger Woods, and Dr. Phil.

The next test is to determine if the song “Bike” by Pink Floyd was written in a drug free state. In case you can’t make them out the lyrics begin:

I’ve got a bike
You can ride it if you like
It’s got a basket
A bell that rings
And things to make it look good
I’d give it to you if I could
But I borrowed it

Available video of Pink Floyd’s Bike (blocked currently at Youtube)

and if Pink Floyd is just not your cup of tea. Here is Queen performing their song “Bicycle Race”

Biology Running Sports Medicine

Overuse Injuries: All The Small Things (repost 10/2010)

Podiatry Management (October, 2010) has just published an article I’ve written titled  Overuse Injuries: All The Small Things . You are just another click away from the PDF version. This is a challenging article. It introduces mechanotransduction, a theory of cellular and tissue function, which is little known in the sports medicine community. The article touches lightly on this topic and then reviews the latest literature and theory on overuse injuries to bone and tendon.

The Needle - Kenneth Snelson
The Needle - Kenneth Snelson

The cellular level is where things start and where we will find many answers. I expect to add more details on the web site on mechanotransduction and mechanobiology for those with hardcore, deep science interest. The article is limited in size, but was longer than many published in PM Magazine. But, I didn’t even touch on the theory canalicular flow and osteocyte induction or mechanotransduction and control of stem cell development by matrix stiffness. Research in the field of mechanobiology is growing daily and the outlook is great that it will be fruitful.


Digital Radiology Data In The Office: Standards (Repost 09/2010)

Osirix Image
Osirix Image

X-rays, MRIs and The Mac

Digitization of Radiology Film

There has been a trend to the increasing digitization of radiology information. This works great on  Mac computers since Osirix Imaging Software has been a global favorite of radiologists for several years. In fact a 2007 white paper detailing the integration of this open source software at a hospital in Mannheim is available at:

Osirix works wonderfully for 2D and 3D information. It is a 2D viewer, 3D viewer, 4d viewer (time dimension) and a 5D viewer (3D data + temporal and functional data) It can integrate images derived from 2 sources such as Cardiac PET/CT angiogram. X-rays, bone scans, pet scans, cat scans and more are readily viewable.  I’ve used Osirix for about 3 years and find it reliable and helpful. It is great for MRIs. I’ve found clinical problems, such as a torn plantar plate, that had previously been mistakenly read as normal. (Of course a physical examination should go a long way in leading one to suspect a plantar plate injury.)

The standard file format DICOM and over 20 other file formats are easily read using Osirix. The DICOM standard allows physicians using software and systems from different vendors to rapidly share imaging information. The only time Osirix will not work is if a proprietary format is used. The disks are sometimes hostilely marked “not compatible with Apple Macintosh computers”.  Since every radiology center has the capability of outputting a standard format file, and it is readable by their own Microsoft Explorer based software, I don’t know why anyone would limit the readability of the disk. In fact, there is no good reason not to use DICOM format. But if by chance a radiology center near you has made the mistake of not using DICOM, that error is quickly remedied with a call requesting a standard format “DICCOM” disk. Osirix development is open source and distributed under the GNU Lesser General Public License.

What is DICOM?

DICOM is a radiological information standard file format. It is the de facto standard used in all hospitals worldwide. The file format was developed in 1993 and used for a variety of medical image types including MRI, CT, and Pet scan. The image is compressible. The National Electrical manufacturers Association (NEMA) created the standard and these same manufacturers embed the capability of creating these standard file formats for cross platform interoperability.

DICOM can even store information on radiation exposure for examinations. It is dependent on the device manufacturer to properly implement this using the current addendum to the standard called the “Radiation Dose Structured Report“. Phillips and GE create a separate image with the total exposure listed. For more details see David Clunie’s Blog.

MEDX3D format is a new format with ongoing work to incorporate the upcoming format in the DICOM standard and in OSIRIX.

The NEMA online brochure explains the format in simple English:


Osirix Imaging Software

Osirix for iPhone/iPod Touch

Radscaper – Dicom viewer via browser that doesn’t use ActiveX for windows and Linux. Uses a Java applet.

Windows DICOM Viewer: DICOMWorks 1.3.5

DICOM – Latest Standard (doc and pdf formats)

Future of DICOM –

What Going Digital Will Mean For the Dentist’s Office – from J Am Dent Assoc

Dave’s Places In Radiology – Extremely thorough site for radiology professionals

David Clunie’s Blog (also see his Medical Image Format Site) – discussions and many links to sites with technical details.

MRI View of Big Mac (


Quadrupedal Human Gait (repost 09/2010)

Quadrupedal Humans
Quadrupedal Humans

Bipedalism (walking upright on two limbs) in hominids is considered a logical and efficient means of locomotion arrived at via hundreds of millions of years of evolution. At the newly instituted PLOS group of blogs a thorough post appearing on the newly moved blog Neuroanthropology describes Turkish individuals who are quadripedal and exhibit what is called Uner Tan Syndrome (UTS). There is some conjecture on the cause of this condition and on whether or not it is evolutionary atavism.

This syndrome was first discovered in 2005 by Üner Tan of Cukurova University in Turkey who is also a member of the Turkish Academy of Sciences.

I note that the quadripedal humans seem to be scurrying along at a fair clip. They are not wearing any coverings on their hands. From the photo it is difficult to determine what they wear on their feet. The video below does show some foot gear. At least some of the quadrupedal humans seem to have the forelimb contact on the heel of the hand, but others may contact further foreward.  I’m sure this will be looked at closer. Evolutionary analysis and better coaching may lead to improved 4 limb locomotion for these individuals. So far I have not come across any reports of any quadrupedal long distance endurance events.

This does appear to be a real syndrome however and the blog describes the symptoms and results of MRI and PET scans on subjects. The findings include:

“signs of cerebellar dysfunction including: intention tremor, dysdiadochokinesis (inability to execute rapidly alternating movements particularly of the limbs), dysmetria (lack of coordination of movement typified by under- or over-shooting the intended position), and nystagmus (involuntary rhythmic eye movement, with the eyes moving quickly in one direction, and then slowly in the other). However, the cerebellar signs are relatively mild, and they are no more pronounced in the quadrupeds than in the one affected brother who walks bipedally.”

My take on this is that the syndrome appears to be an inherited motor and sensory issue (HMSN). There are many disorders in this category with a variety of symptoms. Some of the more common ones include Refsum’s syndrome and Charcot-Marie-Tooth disease .

Both a BBC and PBS Nova documentary have been produced on this condition.


Neuroanthropology Blog Post on “Human Quadrupeds” by Greg Downs – thorough discussion, many reference links

John Hawks Discussion on “Turkish Tetrapods” in 2006

A New Syndrome With Quadripedal Gait Tan, U. Int J Neurosci. 2006 Mar;116(3):361-9.

Family That Walks on all 4s (NOVA show)


Why Here, Why Now, Why Old, Why Not New

Some database issues have made it imperative to recreate the blog comment by comment. And I may not be able to accomplish that. I’ve tried to choose the better ones from the past few years and added them in to the latest WordPress blog software. So that’s why you see some old stuff here.

And hopefully soon, you’ll see some newer material too.

I’ll edit and update the older material where needed.

Aging Neurosciences

Exercise Is Good For Your Brain (Repost)

repost (from November 2011)

Credit: © Eric Isselée / FotoliaCognitive decline with aging is an increasingly important research topic. This past November (2011) Science Magazine produced a special issue on the brain including   a summary article and a main article which discusses the impact on a specific neurodegenerative disease (spinocerebellar ataxia type 1) in mice.

A “mild” exercise regimen helped the mice live significantly longer. The effects lasted for a considerable time, even after stopping the exercise program. The disease studied has features in common with Alzheimer’s in that an insoluble protein that accumulates in nerves is involved. Exercise has been shown to have positive effects on Alzheimer’s disease and the research here on how exercise impacts the proteins and future exercise on a variety of growth factors produced during exercise may help in producing strategies for Alzheimer’s disease and numerous other degenerative diseases.

The accompanying summary article states:

“In addition to the benefits of exercise on brain health and cognitive function, it may promote slowing neurodegenerative disease progression. For example, exercise slowed the decline in cognitive abilities of Alzheimer’s disease patients and improved postural stability and balance in Parkinson’s disease patients.”


Another Reason to ExerciseAaron D. Gitler. Science 4 November 2011: Vol. 334 no. 6056 pp. 606-607. DOI: 10.1126/science.1214714

Exercise and Genetic Rescue of SCA1 via the Transcriptional Repressor Capicua. John D. Fryer, Peng Yu et. al. Science 4 November 2011: Vol. 334 no. 6056 pp. 690-693 DOI: 10.1126/science.121267