#Lower Extremity.#—­The popliteal glands include one superficial gland at the termination of the small saphenous vein, and several deeper ones in relation to the popliteal vessels.  They receive lymph from the toes and foot, and transmit it to the inguinal glands. The femoral glands lie vertically along the upper part of the great saphenous vein, and receive lymph from the leg and foot; from them the lymph passes to the deep inguinal and external iliac glands.  The femoral glands often participate in pyogenic infections entering through the skin of the toes and sole of the foot. The superficial inguinal glands lie along the inguinal (Poupart’s) ligament, and receive lymph from the external genitals, anus, perineum, buttock, and anterior abdominal wall.  The lymph passes on to the deep inguinal and external iliac glands.  The superficial glands through their relations to the genitals are frequently the subject of venereal infection, and also of epithelioma when this disease affects the genitals or anus; they are rarely the seat of tuberculosis. The deep inguinal glands lie on the medial side of the femoral vein, and sometimes within the femoral canal.  They receive lymph from the deep lymphatics of the lower limb, and some of the efferent vessels from the femoral and superficial inguinal glands.  The lymph then passes on through the femoral canal to the external iliac glands.  The extension of malignant disease, whether cancer or sarcoma, can often be traced along these deeper lymphatics into the pelvis, and as the obstruction to the flow of lymph increases there is a corresponding increase in the swollen dropsical condition of the lower limb on the same side.

The glands of the thorax and abdomen will be considered with the surgery of these regions.

INJURIES OF LYMPH VESSELS

Lymph vessels are divided in all wounds, and the lymph that escapes from them is added to any discharge that may be present.  In injuries of larger trunks the lymph may escape in considerable quantity as a colourless, watery fluid—­lymphorrhagia; and the opening through which it escapes is known as a lymphatic fistula.  This has been observed chiefly after extensive operation for the removal of malignant glands in the groin where there already exists a considerable degree of obstruction to the lymph stream, and in such cases the lymph, including that which has accumulated in the vessels of the limb, may escape in such abundance as to soak through large dressings and delay healing.  Ultimately new lymph channels are formed, so that at the end of from four to six weeks the discharge of lymph ceases and the wound heals.

Lymphatic Oedema.—­When the lymphatic return from a limb has been seriously interfered with,—­as, for example, when the axillary contents has been completely cleared out in operating for cancer of the breast,—­a condition of lymphatic oedema may result, the arm becoming swollen, tight, and heavy.