Palpation involves feeling the skin and noting differences in temperature. As one moves from the groin to the foot, there will be a temperature drop. A comparison can be made between the right and left legs. Increased areas of temperature may suggest inflammation; decreased areas of temperature may suggest a reduced circulation. The pulses should be examined. When feeling for a pulse, one is feeling, first, whether the pulse is present or absent; secondly, whether it is weak or strong; thirdly, whether it is regular or irregular; and, finally, whether the artery feels hard or soft, in an attempt to determine the nature of the vessel wall. The best way to feel a pulse is to identify its position by using bony landmarks. If the doctor feels in the wrong place, then he will not know whether the pulse is absent because he is feeling in the wrong place or whether it is absent because the artery itself is blocked. A femoral pulse is felt at a point midway between the superior anterior iliac spine and the symphysis pubis. The popliteal pulse is felt in the midline immediately behind the knee. In most normal people, it is not possible to palpate this pulse. The presence of a readily palpable popliteal pulse may suggest aneurysmal dilatation of the artery. One would normally expect to palpate foot pulses – the dorsalis pedis pulse is felt on the front of the foot, while the posterior tibial pulse is felt immediately behind the medial malleolus. It is almost as important to record whether these pulses are present as it is to record that they are absent.