Dłuski's dissertation: the scientific background of Yumeiho

Origin of the work

The dissertation was written at the Faculty of Mechanical Engineering and Aeronautics, Rzeszów University of Technology (Politechnika Rzeszowska). It was completed in 2015 and defended on 9 March 2016; the supervisor was Professor Stanisław Mazurkiewicz. The original is in Polish. The author, Maciej Dłuski, also directs Yumeiho Europe at the ART Centrum in Rzeszów. It is a dissertation in mechanics, specialising in biomechanics, combining a large palpation-based clinical dataset with a finite element (FEM) model. In the experimental part, pelvic position was corrected using the techniques of the Japanese manual method Yumeiho.

Main thesis

The main thesis was that a congenital asymmetric position of the pelvic bones may affect displacements and deformations of the spinal column and initiate lateral curvature. The reviewers noted that the stated aims read as theses, that is, claims the research set out to confirm.

The four experimental studies

Study 4.1 analysed 18,071 cases by palpation. The direction and magnitude of pelvic asymmetry were associated with the shape and size of the curvature.

Study 4.2 examined the centre of gravity in 303 subjects and found no association between its position and pelvic position. A null result rules out one explanation but does not by itself establish another.

Study 4.3 compared 101 families. All figures come from the same palpation dataset, and the correlation varied with the variable compared: 0.40 for magnitude and direction of displacement, 0.58 for direction, and 0.85 for the type and occurrence of asymmetry. Father–child correlations were weak and negative (−0.11 to −0.22). A peer-reviewed subset of this material (60 families) was published as a poster in Scoliosis: mother–child 0.65 and 0.93, father–child −0.24 and −0.34.

Study 4.4 followed 3,034 children over five consecutive visits at intervals of one to four months, with pelvic position corrected using Yumeiho techniques. Curves were mild (Cobb angle no more than 25°). Within this group, the proportion in which curvature was observed fell from 98% to 28% across the five visits, and most of the change occurred after the first correction. There was no comparison group whose pelvic position was left uncorrected, so the figures describe change within the treated group and do not by themselves separate the effect of correction from other factors such as growth.

The FEM model

A finite element model of the spine and pelvis was built in ADINA with 360,426 elements and 24 vertebrae. When the pelvis was tilted, the model produced first a C-shaped and then an S-shaped curvature, with the Cobb angle increasing with tilt; the largest deformations occurred at the L2–L3 and Th6–Th7 discs. The model shows that the proposed mechanism is physically possible under its own assumptions. It is not independent confirmation: both reviewers considered it heavily simplified, omitting the rib cage, muscles and ligaments, with the entire load carried through the intervertebral discs.

What the findings do and do not show

A correlation indicates an association, not a mechanism. The mother–child pattern is not readily explained by ordinary biparental genetic inheritance, in which the father's contribution would also appear; Dłuski therefore considers mechanical transmission during fetal life or birth the most likely explanation. This is his hypothesis, consistent with and supported by his data, rather than an established physiological fact, and genetic factors are not ruled out. Reviewer Gzik regarded lateral curvature as arising from genetic and biomechanical factors together. The idea that correcting pelvic asymmetry in a growing child could affect the next generation is likewise an inference; confirming it would require follow-up across generations, which this material does not contain.

Review and later publication

The reviewers were dr hab. Celina Pezowicz (Wrocław University of Science and Technology) and Professor Marek Gzik (Silesian University of Technology). Both recommended the dissertation for public defence. They regarded the size of the dataset and the follow-up during growth as its main strengths. Their criticisms concerned the measurement error and repeatability of palpation, the narrow literature review, and the simplifications of the FEM model; Gzik advised caution in the final conclusions. Both reviews are publicly available on the university website.

The biomechanical interpretation was later presented at an international spinal deformities congress and published in the conference proceedings. That paper reinterprets the same dataset and is not a controlled trial.

Reading the dissertation

The dissertation is written in Polish. An English translation exists, and the work has also been translated into Finnish. This page is a summary; the full data, methods and references are in the work itself.

Sources

Dłuski M. (2015). Mechanika skrzywienia kręgosłupa w następstwie asymetrii kości miednicy [Mechanics of lateral curvature of the spine in the context of asymmetric pelvic bones]. Doctoral dissertation, Rzeszów University of Technology; defended 9 March 2016.

Dłuski M. J. (2015). Scoliosis 10 (Suppl 1), P14. DOI 10.1186/1748-7161-10-S1-P14.

Dłuski M., Cyprys K. (2026). Studies in Health Technology and Informatics. DOI 10.3233/SHTI260772 (CC BY-NC 4.0).