I have/use a memory foam pad I got for xmas 2007. I love mine. It has reduced the hip pain I get from staying in one position too long.
The downside is that it does retain your body heat. It's better for colder months. For me I wake up very shaky from being over heated while asleep. It lasts a few minutes and I'm fine.
I wouldn't trade it except for a sleep number bed. I hear those are awesome.
Good luck with your search for relief.

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