In almost all cases dentition is prolonged by rachitis ; oftentimes children begin their second year with no teeth, although the termina tion of the first dentition in such children usually occurs in the third year. A characteristic phenomenon is the cutting of many teeth in close succession after a considerable period of time. As a rule rachitic teeth are less resistant than normal ones, and the enamel often shows horizon tal and longitudinal striations or roundish depressions. Frequently the teeth are discolored; they may be yellowish, brown, black or greenish gray. They are inclined to become carious and to fall out, or they grad ually crumble down to the alveolar edge. Sometimes only the upper teeth behave in this manner while those in the lower jaw remain intact.
In the cranium, long standing rachitis leads to a thickening of the frontal and parietal tuberosities which, with marked prominence of the tubera frontalia and a simultaneous flattening of the occiput, gives a cubical or dice-like shape to the skull. These are cases of so-called "caput quadratum" or square head.
In rachitic children the large fontanelle often reaches an abnormal size, and is often closed only at the end of the second year or even later. The small fontanelle and the two posterior lateral fontanelles remain open in many cases an abnormally long time, as do the longitudinal, the corona] and the lambdoidal sutures. The bony edges of the large fontanelle are often so soft, either partially or throughout their whole extent, that they can be easily depressed. Often other places in the skull are soft and compressible. This so-called "craniotabes" occurs principally in the region of the lambdoidal suture and the small fonta nelle; it may however extend far into the occipital bone or into the posterior part of the parietal bones. The soft areas arc usually about the size of a dime but they not infrequently unite to form larger areas, and in the severest cases the softening affects almost the entire occiput. The latter is flattened in all severe cases. The temporal veins are fre quently markedly dilated in severe cranial rachitis.
The rachitic spinal curvature as a rule does not form an angular projection hut rather a more or less gentle bend. !lost frequently one finds a kyphosis which, in typical cases, involves the lower dorsal and lumbar vertebne. Next in frequency is the dextro-convex-dorsal scoli osis; as a rule a second curve is present compensatory to the first.
In the thorax the most constant symptom of rachitis is the occur rence of a row of bead-like enlargements Nv hich run from above anteri orly to below laterally at the junction of the bony and cartilaginous portions of the ribs, the so-called rachitic "rosary." These enlargements
are more pronounced on the lower than on the upper ribs; that upon the 11th rib occurs normally in about the mid-axillary line. On closer examination each single nodule consists usually of two swellings sepa rated by a furrow, one of which belongs to the osseous and the other to the cartilaginous part of the rib. In emaciated children the rosary is plainly visible but in fat or even well nourished individuals it can be demonstrated only by palpation.
In the majority of severely affected children a still further mal formation of the thorax is associated with the rosary. The most impor tant visible evidence of this is the flattening of the lateral chest Nvall. This flattening is most marked as a rule between the mammary and postaxillary lines and between the 4th and 7th ribs. In severe cases, in place of the normal bowing of the lateral chest wall with the convex ity outward, a more or less deep hollow is present, so that here the ribs describe a curve with a concavity outward. In contrast to the lateral wall of the chest the sternum in these cases usually projects forward, and if a kyphosis exists at the same time the sternum curves convexly forward from above downward. In rare cases the deformity does not assume the classical form of the rachitic "chicken breast," but with the typical flattening of the chest wall the sternum lies somewhat depressed between the very prominent costal cartilages. The posterior surface of the rachitic thorax is abnormally flattened and the borders between the posterior and lateral walls are usually prominent. In contrast to the flattening of the central portions of the chest wall, the lowest part projects outward, the sharp transition from one to the other forming the so-called "Harrison's grooves" which run around the chest at the level of the diaphragm.
As a whole the chest appears strikingly small in its upper two thirds, especially in comparison with the head and belly. The deformity of the thorax in rachitis is caused on the one hand by the abnormal weakness of the chest wall which yields in time to the diaphragmatic contractions at each inspiration and to the elastic pull by the collapsing lungs at expiration, and on the other to the continual pressure exerted by the overlying upper arms. The flattening of the posterior chest wall is the result of the continuous dorsal decubitus. The bulging of the costal margin is caused by the rachitic enlargement of the liver.