[Regional differences in the chemical composition of the human tibia].

The chemical homogeneity in all parts of the bone compacta was investigated in 2 human tibiae taken from male cadavers. The ash and nitrogen contents were used as parameters of the chemical homogeneity. Analyses for calcium and phosphorus were performed in addition to characterize the ash content. The mineral components reached their highest levels in the middle of the diaphysis, but the ash contents decline in the directions towards the epiphysis. The distributions of the values for the organic compounds (nitrogen) show a converse pattern. The nitrogen content was highest especially at points where tendons are anchored in the compacta. The ash or mineral content is approximately proportional to the density of the dry bone substance. The chemical composition of the bone compacta can therefore be used to draw conclusions regarding zones that are subject to different functional loads.