Among the less frequent bone changes in late hereditary syphilis is a rarefying periostitis leading to bone absorption. This occurs occa sionally on the surface of the cranial bones and may lead to extensive resorption of bone with the formation of rough areas on the surface (caries sicca).
Just as in the tertiary stage of acquired syphilis, there occur at times in late hereditary syphilis nodular periosteal swellings (gummata) with their favorite location again in the tibia, but also in the bones of the upper extremity, the cranium, and the sternum. These are at first rather soft, sensitive swellings that are surrounded by a wall of hyper ostosis. They either heal, leaving a depression, or discharge and become converted into thick walled, excavated ulcers which heal with the formation of adherent scars. If the gummatous process is centrally located, bone necrosis may result.
The short hollow bones, too, may be involved in late hereditary syphilis, but these lesions no longer show a typical course with pref erence for the first phalanges of the fingers, but occur without any definite rule in the phalanges, carpus, and bones of the foot.
The lesions of the nose and of the alveolar processes show no differ ences in acquired and in late hereditary syphilis. Perforations of the bone that are rare in early syphilis, are of frequent occurrence at this stage.
Not infrequently, hereditary syphilis leads to lengthening of the affected long bones in older children. This is especially striking in the occasional lengthening of a lower extremity, like a partial gigantism, in which the affected bones become plump and rougher. Frequently such bone changes are preceded for months, even years, by severe nocturnal headaches.
In late hereditary syphilis genuine syphilitic joint lesions of a very definite type occur. The knee-joints are most frequently involved, at times, even during youth and adult life. According to my experience two main types can de distinguished: 1. Joint affections without involvement of the bone and cartilage.— These naturally fall into two subdivisions: (a) simple hydrops of the joints without material thickening of the joint capsules, the sVnovial membranes and the tendon sheaths; running an afebrile, almost painless course; it is almost exclusively limited to the knee and ankle-joints and causes a slight feeling of weariness and weight in the legs; (b) hyperplastic synovitis. In this form the joint capsule, the
svnovial membranes, together with the tendon sheaths, are all thick ened and almost gelatinous. Friction rubs can usually be heard and felt in these joints. This process may involve the phalangeal and carpal joints, then the smaller joints of the foot, in fact may spread to every joint in the body, including those between the vertebra, as a generalized hyperplastic arthromeningitis.
2. Joint affections with enlargement of the ends of the bones.— These likewise fall into two subdivisions: (a) combination of hydar throSis with swelling of the joint ends of the hollow bones. This is the most common form of joint affection in late hereditary syphilis, resembling not a little the clinical picture of arthritis deformans. It is important from a diagnostic standpoint that the swollen bone ends are not sensitive to pressure. The Röntgen ray, too, shows there no peri osteal layer formation as in the affections of the diaphysis; (b) an affec tion simulating white swelling. This is usually monarticula-r, painful, and is associated with limitation of motion, like the tuberculous form. It may lead to rupture and to necrosis.
It is especially important. for the pediatrist to he able to distinguish between tuberculous, or scrofulous, and syphilitic bone and joint affec tions. In general, caries is more frequent in tuberculosis than in heredi tary syphilis. The syphilitic bone affections are less tender than those due to tuberculosis and produce fewer functional disturbances. In bone syphilis of later childhood, too, there is an absence of hectic fever and of the profound cachexia of bone tuberculosis. In the cases that go on to suppuration the nature of the skin involvement may lead to a diff erential diagnosis. The peculiar character of the skin in scrofulous caries, the violet discoloration, the manner of perforating, the formation of multiple fistulas, and the spongy granulations, all speak unquali fiedly for tuberculosis and are absent in syphilis.