Peritonitis is defined as inflammation of the peritoneum. The inflammatory response involves vasodilation, exudation of protein-rich fluid, cellular infiltration, pain and, chronically, formation of fibrous adhesion. The disease can be classified into primary and secondary cases.
It begins in the venous plexus along the medial side of the foot, and it runs up the medial side of the leg and knee, alongside the saphenous nerve. In the thigh, the long saphenous vein continues up the medial surface, accompanying the medial femoral cutaneous nerve.
The femoral vein and artery are side by side, so once the artery is found, so is the vein. The femoral vein, like most veins, carries deoxygenated blood to the heart. If the femoral vein becomes blocked by a blood clot, blood will be unable to drain from the leg. The femoral vein lies beside the femoral artery, which supplies the femoral pulse.