This is quite a common complaint. To think about why the heel pain happens, push a finger into your skin and take it away. There will be a white spot that goes back to normal colour quite quickly. The whiteness occurs because the blood gets squeezed out of the tissue by pressure. When you lay in bed, you usually do so for hours on end and the blood gets pushed out of the skin that rests on the bed under the weight of your body. These sensations feedback to your brain as you sleep and cause you to shift during the night which generally means that healthy people won’t experience the problem whereby heels hurt in bed at night.
If you are confined to bed for long periods, take medications that make you sleep very deeply or have an underlying problem with the blood flow to the feet, you may be prone to suffering this kind of ‘bed sore’. The problem becomes more common with advancing age because the collagen in the skin becomes less springy and less able to withstand pressure. Added to this, the fat layer under the skin around the feet and ankles lessens as you age making this problem much more likely.
The best first step to resolve the pressure issue is the use of a sheepskin blanket directly below the heels. Also, make sure the blankets are as light as possible and/or use something in the bed to prop the weight of the bedclothes off the feet. Many times, this will be all that is required.
In more severe cases, specialty pressure diffusing mattresses may be required from a orthopaedic supply company. They can also supply a blanket lift bar or blanket support that is specially made to fit under a mattress and keep the feet free from extra weight.