[Biomechanics of vertebral segments. Clinical and prognostical interpretations (author's transl)].

The authors propose a new model to estimate the forces of the intrinsic equilibrium of the segment. Based on the theory of the so-called transient pole, it became possible to describe the momentary movement of an angle relative to its neighbour and to define the way of the intrinsic equilibrium. This transient pole fixes the centre of rotation around which the upper angle moves relative to the lower vertebral body. Normal and pathological cases can be diagnosed at once by use of a special röntgenological appliance in connection with the statistical experience. It becomes possible to calculate the forces and movements acting on a segment.