‘Pins ins and Needles’ is referred to the tingling sensation we feel in our hands, feet, arms or legs when the blood begins to circulate in those areas after being impeded for some time. For example, when we sit with our legs curled up in one position for a long time and then try to stand up, we sometimes get the feeling of numbness as if one of our leg had ‘fallen asleep’. As the blood begins to flow again, the familiar tingling sensation occurs due to the change. But why do we get this tingling sensation?
We know that the blood flows freely through the blood vessels in our body, just as water flows freely through a stretched hose. Imagine what would happen if you bent the hose! Water would only trickle through. Similarly blood is the transport system of our body and performs two important functions. It supplies food and oxygen to different parts of the body as well as collects the poisonous wastes. When a recession occurs in the flow these poisonous wastes accumulate and block the nerve cells from carrying messages from the foot to the brain. This results in the feeling of numbness. Again when the leg is stretched, the blood starts flowing again and this change causes the tingling sensation.