GANGLIA Similar symptoms:, though their etiology and structure are entirely different, are caused by cystic tumors which are observed in different parts of the body, near joints and tendon-sheaths, and are formed by the tying off and sacculation of the joint-capsule or tendon-sheath, and are called "ganglia." They are most frequently found on the back of the hand, near the joints of the foot, occasionally also at the back of the knee-joint near the large flexor tendons.
The wall of these cysts shows the structure of the capsule or the tendon-sheath, with which the ganglion may still be united, either com municating with the joint or tendon-sheath by a duct, or this duct may have become impervious and the strangulated part have developed as an independent cyst. Its growth is slow and the symptoms depend upon the location of the swelling. The skin is always movable over the cyst, which feels firmer than a lymph-cyst, is not pervious to light; its con tents are thicker, jelly-like, the cyst is filled tightly and is hard.
The treatment consists in extirpation, and when doing this we must always remember that it may communicate with the joint-cavity (easily infected). Before deciding on an operation we may try to break the cyst subcutaneously, and in a large percentage it will not recur (Lexer).
3. Sarcoma Pathologic Anatomy. — These connective-tissue tumors are very malignant and, owing to their rapid growth, they are mostly formed of young, undeveloped, and undifferentiated cells. They may arise from all the different kinds of connective tissue of the body and will show their respective structures, though the exceedingly rapid growth will make them lose their peculiar structure and they will look more and more like embryonal connective tissue.
Their malignancy is based upon the exuberant growth, by which they push aside, pervade, supplant, and choke all other tissue.
On account of their deficiency in blood-vessels, they break down easily and become necrotic. Cells which have grown into the blood channel become separated and are carried on, and these have the faculty to grow in other localities and to produce metastases. We can easily
understand that their close relationship to embryonal structures makes these tumors relatively frequent in the growing body of the child. We even observe, and by no means rarely, congenital sarcomata in children.
The skin, the bones, and the glandular organs are the favorite sites of sarcomata in children.
The sarcoma of the bone is the one most frequently observed, from the relatively benign giant-cell sarcomata originating from the jierios teum of the jaws (epulis) to the malignant soft spindle-cell sarcomata of the joints.
We differentiate two types according to their origin: the periosteal and the myelogenous.
The periosteal type begins as circumscribed tumors of the bone which are covered by a thin layer of periosteum, most frequently near the metaphysis (Lexer). At first they can be separated from the bone, but soon they attack this as well and then spread rapidly to the inside of the bone and also into the surrounding soft parts (Fig. 189, Plate 21).
The myelogenous type starts from the bone-marrow, and we observe this most frequently close to the cartilaginous border in the spongiosa, whence it fills the bone gradually (Figs. 190, 191).
The bone is distended and thinned from the inside. The tumor itself may break down on its interior, thus causing the formation of cavities and bony cysts. In the benign giant-cell osteosarcoma this stage may persist for a long time (spontaneous fracture), though the tumor may at any time resume its tendency to rapid growth and may cause the death of the patient from the formation of metastases in the internal organs.
The Diagnosis.—The recognition of osteosarcomata can be difficult only in the very beginning. Osteomyelitic processes will give the same appearance externally as well as skiagraphically, but the inflammatory character of t he osteomyelitic process, with its redness, suppuration, fever, and pain, will show us the difference.