Femoral artery
The femoral artery is a large artery in the thigh and the main arterial supply to the thigh and leg. The femoral artery gives off the deep femoral artery or profunda femoris artery and descends along the anteromedial part of the thigh in the femoral triangle. It enters and passes through the adductor canal, and becomes the popliteal artery as it passes through the adductor hiatus in the adductor magnus near the junction of the middle and distal thirds of the thigh. Structure. The femoral artery enters the thigh from behind the inguinal ligament as the continuation of  the external iliac artery. Here, it lies midway between the anterior superior iliac spine and the symphysis pubis (Mid-inguinal point). Segments. In clinical parlance, the femoral artery has the following segments: Relations. The "relations" of the femoral artery are as follows: Clinical significance. Vascular access. As the pulsation of the common femoral artery can often be palpated through the skin; and the site of maximum pulsation is used as a point of puncture for catheter access. Common femoral artery (CFA) can be assessed by retrograde puncture. Then another catheter is advanced through the common iliac artery to the contralateral  external iliac artery and contralateral superficial femoral artery (SFA). The SFA can be assessed by antegrade puncture after the contralateral retrograde puncture was done. From here, wires and catheters can be directed anywhere in the arterial system for intervention or diagnostics, including the heart, brain, kidneys, arms and legs. The direction of the needle in the femoral artery can be against blood flow (retro-grade), for intervention and diagnostic towards the heart and opposite leg, or with the flow (ante-grade or ipsi-lateral) for diagnostics and intervention on the same leg. Access in either the left or right femoral  artery is possible and depends on the type of intervention or diagnostic. The site for optimally palpating the "femoral pulse" is in the inner thigh, at the mid-inguinal point, halfway between the pubic symphysis and anterior superior iliac spine. Presence of a "femoral pulse" has been estimated to indicate a systolic blood pressure of more than 50 mmHg, as given by the 50% percentile. The femoral artery can be used to draw arterial blood when the blood pressure is so low that the radial or brachial arteries cannot be located. Peripheral arterial disease. The femoral artery is susceptible  to peripheral arterial disease. When it is blocked through atherosclerosis, percutaneous intervention with access from the opposite femoral may be needed. Endarterectomy, a surgical cut down and removal of the plaque of the femoral artery is also common. If the femoral artery has to be ligated surgically to treat a popliteal aneurysm, blood can still reach the popliteal artery distal to the ligation via the genicular anastomosis. However, if flow in the femoral artery of a normal leg is suddenly disrupted, blood flow distally is rarely sufficient. The reason for this is the fact that the genicular anastomosis is only  present in a minority of individuals and is always undeveloped when disease in the femoral artery is absent.