The spine – a masterpiece of evolution,
optimized for upright gait
Many specialists such as doctors and counselling institutions and also bed dealers try to explain the problem of widespread low back pain by pointing out that the human spine is not actually designed for an upright posture and is therefore subject to particularly severe wear and tear (for examples, see appendix below).
Researchers at the University of Munich contradict the legend of the misconstruction of the human spine:
Professor Reinhard Putz from the Institute of Anatomy at the University of Munich draws on the results of his “Musculoskeletal System Research Group”. He does not consider the spine unsuitable at all, but sees it as a highly adapted structure for the upright walk, a masterly development of evolution between the requirements for maximum stability on the one hand and maximum mobility on the other.
The assertion that the spine is not designed for the upright posture is based on the assumption that in humans the weight of the upper parts of the body puts too much pressure on the spine, especially in the lumbar region, while in four-legged animals the horizontal alignment exerts little pressure on the longitudinal axis of the spine and this is at best loaded by lateral movements. However, this is a wrong conclusion, because also with the quadrupeds a strong pressure along the axis of the spinal column is built up over the ligament system, because otherwise front and rear part of the animals would simply fold up.
According to Prof. Putz’s research, the strain on the spinal column between the four-legged friends and the upright walkers has not changed fundamentally. On the contrary, the muscle work becomes even easier, since the pelvis has also erected (turned) with the spine. By turning the pelvis, the erect spine receives a stable base, which enables the human being to move the upper parts of the body (arms, shoulders and torso) in a way that is peculiar to him.
In his morphological analysis, Reinhard Putz identifies the special abilities of the human “locomotor system” as an optimal “evolutionary compromise” between mobility and stability.
Thus, the ligaments along the spine are by no means to be understood as a passive traction system that simply holds the vertebrae together, but as a “kind of gear that precisely coordinates the displacement of the respective adjacent vertebrae”. The decisive factor here is that the reaching of the end position of a movement is delayed and damped in a coordinated manner. This function has the effect that despite high mobility hardly any tissue damage occurs. The prerequisite for this is that “the straps as a whole are under sufficient pretension. Ensuring this pre-tensioning is again an important function of the “intervertebral discs”.
The results of the research group also contradict the usual view that the intervertebral discs should be reduced to simple buffer functions. The intervertebral discs maintain the pretension of the ligaments and ensure an even distribution of pressure between the adjacent vertebral bodies. In addition, they are also integrated into the “control of mobility”. But they “are in no way able to absorb or even dampen axial shocks to a greater extent” as is commonly assumed. Rather, this is done by the flexible yielding (flattening) of the s-shaped alignment of the spine, i.e. also via the ligament system.
Interesting is the interpretation of the fact that the outer ring of the intervertebral discs (Anulus fibrosus) is not uniform in the bony marginal ridge, but narrower and thinner on the back side: “Apparently, in accordance with the constant (main) shear stress during rotation of the lumbar spine, the front part of the anulus is thickened, while the rear part also maintains a correspondingly lower level of manifestation. This should not be misunderstood as degeneration.” “Anulus fibrosus in the lumbar spine plays an important role in limiting rotation as a partner of the spine.
In summary, Prof. Putz finds in his analysis that the structure of the mobile segments in the lumbar region is organized like a highly differentiated transmission system and exhibits an extraordinarily high degree of adaptation to the needs of the upright human being.
When asked why so many back complaints occur despite this high adjustment of the spinal column, Reinhard Putz refers to the modern, exclusively seated activities of people as well as to the exaggerated sporting demands which “no first-class biomechanical make of evolution can cope with”.
Sources:
Report of the FAZ of 05.04.2006 about the conference “The Bone as Archive”.
Lecture by Prof. Dr. Reinhar Putz at the 3rd Annual Meeting of the German Society of Biomechanics 2003.
Author’s comment:
The insight that the human spine is optimally developed for the upright gait may be new for many medical doctors, but this position has long been held outside classical medicine, although it has been addressed and practiced in other ways, as, for example, in Ida Rolfing (Rolfing) and in the publications of Moshé Feldenkrais.
Attachment:
Quote 1:
“Source of pain: the upright walk.
Evolution, more precisely, our upright walk is to blame for all the pain in the back. It took millions of years for humans to develop from four-legged friends to two-legged friends – “Homo erectus”. “In this development, the spine and back muscles have assumed functions for which they are not designed.”
Source: Bayrischer Rundfunk online: www.br-online.de/umwelt-gesundheit/thema/ruecken/schwachstelle-kreuz.xml
Quote 2
“Upright walk isn’t really for people”
The evil “back pain” often has ancient roots: Man is not made to walk upright. This is shown by the frequent back problems of bipeds and also the posture of some employees in middle hierarchical levels. The backbone is actually “optimized” for four-legged friends.
Source: Ratgeberverlag http://www.aerztelatein.de