The Putnams Memory Foam Knee Cushion is designed to go between your legs as you sleep in order to keep your pelvis, spine and legs at a comfortable angle. There's a strap to keep it in position. Fans of this cushion say that it helped them get a good night's sleep before and after a hip operation. The only downside is that the strap can take a bit of getting used to, especially when you move around in the night. If you have hip pain, this cushion could be your ticket to a comfortable night's sleep.