Summary
The oste‐ochondral junctions of the first or second and the sixth or seventh rib have been removed from foetuses and infants in 527 consecutive autopsies and examined histologically for the occurrence of changes typical of rickets. The distribution of the series following birth weight and age appears from Table 1. The following histological changes have been searched for: A, Broadening and gross irregularity of the osteochondral junction; B, irregular arrangement of the cartilage cells at the ossification zone; C, occurrence of considerable amounts of osteoid at the ossification zone and in the spongiosa. Concerning two of the changes one narrower (A, C) and one wider (a, c) definition have here been used.
All these histological changes have been found in all weight and age groups (Table 3). A marked correlation has been proved between the different changes (Table 6). The fully developed histological picture of rickets (ABC) likewise has been found, though sparsely, in all weight and age groups of the series, except in the stillborn infants of the highest weight group (the full term). On the other hand, an entirely “normal” bone structure, free from histological signs of rickets, has also been found in all weight and age groups. The incidence of cases with such “normal” findings is significantly higher in the higher weight groups than in the lower ones, and higher, though not significantly so, in the stillborn than in those who lived after birth.
In 309 cases roentgen pictures of the left hand have been made prior to autopsy. These pictures have been normal in most cases. Slight roentgenological changes have been observed mainly in foetuses of less than 300g of weight, and they have been found in those showing histological signs of rickets as well as in the others.
We have searched for a possible association between the histological findings and the following factors: Vitamin D intake and exposure to sunshine of the mothers during pregnancy, home district of the mothers (Malmö 56oN, Uppsala 60oN, or Sundsvall 62oN), their mineral supply during pregnancy, the levels of calcium, inorganic phosphorus and phosphatase in their blood serum following delivery, their number of children, the sequence of pregnancies and lactations, and social conditions. Nothing has appeared indicating that shortage of vitamin D or defective supply of minerals to the pregnant mother are of importance for the development of the histological findings in the foetus or child.
The interpretation of the findings is difficult. Apparently the changes in bone structure are caused by a discrepancy between bone growth and mineralization, but the cause of this discrepancy is open to discussion.
Aspects histologiquea caractéristiques du rachitisme chez des foetus et des nourrisssons.
Au cours de 527 autopsies de foetus ou de nourrissons on a procédé systématiquement à l'ablation de la jonction ostéo‐chondrale de la première ou deuxième côte, et de la 6e ou 7e côte, puis à leur étude histologique. Les modifications histologiques suivantes ont ét...
