Rickets, Or Rachitis, is a condition of childhood that is indicated by structural changes of the bones, particularly those of the pelvis and of the lower extremities. It is characterized by an excessive formation of cartilaginous bone followed by a deficient deposit of bony salts. Such bones are not perfectly rigid and tend to show more or less deformities on that account. Eventually enough salts may be deposited to render the bone rigid, but it will retain its irregular structure. In these children dentition is late and the teeth readily undergo carious changes.

If larger amounts of food are taken than are necessary for the bodily requirements, the excess will be carried through the intestines unacted upon. It may result in an excessive formation of fatty tissue, giving rise to the condition known as obesity or polysarcia. This is due either to the excessive absorption of food, either fats or substances, like carbohydrates, whose catabolism yields fats, or to inadequate combustion of the fats so acquired. In some cases both factors may play a part.

In asphyxia there is a lack in the amount of oxygen and an increase in the carbon dioxid. In this process there is first a period of increase in the inspiratory efforts, then in the expiratory, and finally exhaustion. After death the heart, particularly the right side, is found to be distended with blood.