Summary

Abstract

Pauwels (1965) and subsequent workers in the same field have shown that the distri­bution of the subchondral density within a joint surface can serve as a parametric measurement which reflects the main stress acting on a joint. Our own investigations on anatomical specimens have demonstrated that this subchondral mineralization does indeed show regular distribution patterns from which conclusions about the mechanical situation within an individual joint may be drawn. Since radiographical densitometry and histological methods are only available for determining the adaptive reaction of the bone to the particular mechanical situation in a joint after death, the information obtained applies only to an end situation and tells us nothing about the development of the changes with time. Furthermore, investigations carried out on human specimens by radiographical densitometry mostly apply to samples of a particular age, since such specimens can be acquired only from departments of pathology, forensic medicine or anatomy. The functional reactions of the bone tissue to repeated long-term changes in the loading - lengthy immobilization and subsequent remobilization, for instance, or heavy loading over a considerable period of time -cannot be followed by any ordinary method in experimental animals, since the death of the animal is a prerequisite for the precise quantitative examination of the bone tissue. This applies also to attempts to follow the process by means of animal experi­ments.