From Digitized Pictures to Biomechanics

Introduction to the numbers being measured and analyzed. Demystification of single localized measures of posture deviations, their limits, and their usefulness in statistics over a population. Introduction to P: percentage of individual improvement, based on measurements of individual deviations from postural alignment, Before and After a Rolfing or Structural Integration treatment.

For our community of Instructors and Practitioners to gain a better understanding of the type of statistical documentation an “Automatic Postural Grade” would allow us to produce, I have made up a few numbers, in the absence of a real set of preliminary numbers.

From Digitized Pictures to Biomechanics

A data set is needed to perform statistical studies. I made up the data set so that it would show a visible amount of change over a population, as I do not doubt that our schools’ student clinics would show a noticeable shift over the population of students clients.

I based this example on a piece of data one particular commercial piece of software produces as a postural overall grade I was explained by the manufacturer that PosturePro measures conventional angular deviations from the alignment in several areas of the structure, in degrees. Then the software uses a proprietary algorithm, which adds up an arbitrary number of these deviations into a Total Deviation measure.

PosturePro’s Total Deviation

See their sample patient report in .pdf format. If you are trying to see a significant difference before and after, you may want to forget about it: this sample could have been made Before and After one quick chiropractic adjustment.

Admittedly, the credibility of PosturePro’s Total Deviation does not even begin to compare to the individual measures of deviations. Biomechanical software can produce (such as a Pelvic Tilt angle of deviation). Note that the same approach could be taken with such individual measures of deviation from alignment, but the point would only be made locally, versus for the whole posture.

PosturePro’s “Total Deviation” is not an absolute measure of posture: measures from client to client cannot be directly compared in complete terms. Moreover, 3 degrees of improvement for one person is not the same as 3 degrees of improvement for another.

The simplicity

The value of PosturePro’s Total Deviation is in simplicity, one number for the whole posture, that’s easy to grasp, easy to present, and accessible to the market. We can think of this approach in general, not as a scientific one, but as a pre-scientific method, one that could invite more scientific scrutiny, while allowing us to produce our data and present them in a marketing effort.

In this perspective, we can safely compare one person’s degrees of improvement with whatever the “Total Deviation” was at the beginning of the treatment for that person. This gives us the Column of P, which tells us how much people have changed, relatively to their posture before the Ten Series of Rolfing or Structural Integration.

For example, going from a 10-degree deviation before the 10-series to 5 degrees after, would be a 50% improvement of posture for this individual. From 10 to 0 would represent a 100% improvement, where the body became fully aligned at the end of the 10-series. Staying with the same 10 degrees of deviation before and after represents a null (0%) improvement.

In this Hypothetical Case Study, I synthesize the data in statistical and graphical terms, showing what we could and should present to the general public as well as other health and alternative health professionals.

Credentials issues

This example could use a professional review, as it has not yet been re-examined by a real Statistician, which I am not. A basic Introduction to Statistics class in College is as far as I got, which should be seen as a positive quality for the point I am trying to make, if I did it right: it can be simple and easy.

I believe the general idea would stand a Statistician’s trial, even if some mistakes have been made. Please forgive me should there be such mistakes. Read this article already? Read our other article on Bifocal sunglasses here.