3-D puzzle and wooden foot

 

BY CLEMENS HAGEN

The interdisciplinary seminar for foot treatment is already a tradition in Japan. Every year physicians, pedorthists and physical therapists meet for the joint further education of the treatment of foot problems. Last year the Belgian biomechanic and osteopath Paul Klein was our guest who presented an introduction in biomechanics of human joints.

Usually it begins with a book. Whenever I don’t get any further with my so far collected knowledge, if there are questions on the origin of a pedorthic challenge and solutions are required for the optimum treatment of my clients, I search for ideas in books. This way quite a collection has piled up in my book shelve. In every book you can find a portrait of the author. And some of the books are so fascinating that I get in touch with the author and try to win him for our summer seminars in Japan, hoping that also others are interested in expanding their knowledge.This also happened with Dr. Paul Klein from Brussels and his exciting book on “Biomechanics of human joints” that he wrote together with Peter Sommerfeld. Paul Klein was professor at the “Université Libre de Bruxelles” where he headed the research department for manual therapies. He focuses on applied biomechanics, methodology and epistemological questions in the area of osteopathy and different other manual therapy methods. We could get Paul Klein interested in the idea of our seminar, even if last year our usual “summer seminar” turned into a “fall seminar” due to different delays.Since we started to organize our further education events here in Japan, we have already collected a number of topics around people and shoes. You could almost talk about a 3-D puzzle. If you picture the human body first as an empty, immobilized frame, where slow by slow individual pieces and functional elements, so to speak pieces of a puzzle, are incorporated until in the end a physically functioning person has developed, our enterprise turns into a playful challenge. At any rate, the pieces that were added in the event with Paul Klein suited the so-far acquired knowledge perfectly.

Moving topics
Already in his introduction Dr. Klein explained that we would mainly concentrate on the “forgotten plane”, as he called it, on the transversal plane, during the two days of considerations on the construction and function of the joints of the lower extremity and the human gait. Indeed, in most specialized books the sagittal and frontal planes are in the focus. We impressively realized the far reaching consequences of this neglect in the course of the seminar.
But first it was about the fundamental strategy of bipedal locomotion. In order to understand that, Dr. Klein explained the difference between rolling and sliding and the similarity of our gait with the movement of a caterpillar track.But then also legs came into play. With the help of simplified model displays, step by step the basic function of the big joints from the pelvis downward was explained to us. Here we also learned why two sticks as pendulum would not work for locomotion. Only with the shortening, for example in the knee joint, can a foot be swung forward. Klein explained also that locomotion allocated to several joints also plays an essential role in the shock absorption.

Hip, knee, ankle joint
Still the pendulum is one of the basic functions and this movement mainly takes place in the hip joint. Paul Klein showed us the movement options that can occur in three planes of this joint. With the help of sectional representations he illustrated the effect of angle variations for example in the femoral neck on the foot and leg position or which effects the degree of the overlap angles have on joint stability and degeneration probability. Already with this joint we realized how the different components transfer their effect cranially and also caudally. Also the function of individual important muscles was indicated to us. With trials on preparations, Paul Klein could show during his time as a university professor how for example the rotation effect of the musculus piriformis transfers from the outside to the inside during extension or flexion.
Klein also explained the movement of the knee joint in the sagittal plane - flexion and extension together with a gliding movement - but then he went over to the movement in the frontal and transversal plane. He sensitized us to look at the overall construction of the leg, how for example forces of the femoral muscles operate on the knee joint diagonally, which rotation is possible in the transversal plane in the knee during step development and how there is a transfer function due to that between the lower leg and the thigh. In this context Paul Klein indicated also the “mistakes” in the development of prostheses and ortheses that cannot describe all movements due to their construction. Only if all movement planes are taken into consideration, the technical treatment seems to be really successful. 
Finally we reached the peak of complexity with the ankle joint. Two diagonally positioned movement axes with additional joint planes that develop according to the position caused us quite a headache. The axes apparently are not in an ideal position for any of the movement directions and still result in or rather because of that in the sum of ideal mobility. Dr. Klein could demonstrate these complex coherences with the help of his brought along wooden foot model which has a long teaching history. Here also the focus was mainly on the transversal plane, whereby the rotations can be explained as transfer functions.That was exactly the topic of the last seminar block, the analysis of the entire “chain of movement” between foot and hip joint, from two directions: Top-down and bottom-up analyses.The knowledge communicated by Paul Klein was extensive and complex and we certainly will need to look into it some more before we can integrate it in our daily work. But it was a valuable enrichment for all people participating concerning the understanding of the function of the human locomotor system. The seminar was an ambitious challenge and doubtless a huge final piece for our puzzle.Almost as a tradition, Dartfish supported us with video technology, in order to transfer the various practical exercises and demonstrations to a screen. And again also this time the social aspect of our event did not come up short; the interdisciplinary communication during our small evening event was quite lively.The next pieces for our puzzle have already been booked for the next years and we are hoping for a vivid participation once again. 

Clemens Hagen was trained as a pedorthist in Austria, France, Italy and Germany. He moved to Japan in 1996. Today he runs his own pedorthic workshop in Nagano.