Hi DriaC,
Welcome to the community.
First, sorry for your pain. If foam is causing pressure or discomfort, a featherbed can provide a cloud-like buffer. It doesn’t offer support per se but can make a too-firm mattress feel broken in faster. Also, it is helpful knowing what mattress you are using, your age, height and weight, and sleep position.
Additionally, If side sleeping, place a pillow between your knees to align the hips If back sleeping, a wedge or bolster under your knees can reduce SI joint tension.
Also, you may consider using the incline sleep method. I have written about this in the forum.
This is a great product for the job
Here is a short list of some benefits:
Reduces Pressure on Lower Back and SI Joint (in back sleepers)
Elevating the upper body slightly (10–30 degrees) can reduce lumbar compression
Reduces strain on the pelvis, especially if paired with knee elevation.
Promotes Better Spinal Alignment
If your pelvis is being pulled downward (especially on a firm mattress), an incline can help level out the hips and spine.
Elevating both head and legs (zero gravity position) can relieve gravitational tension in the SI area.
Improves Blood Flow and Relaxation
This can help reduce inflammation and stiffness in the SI joint by promoting circulation.
I had a serious back injury recently back in April, and I happened to own this half wedge topper, which came in extremely handy.
You have several options for your condition. You may not find a solution with one option. It may require a couple of different options to get this under control.
Best of luck,
Maverick