I’d like to share my DIY experience in hopes that it helps or inspires someone.
I’m sleeping on a split level latex mattress. There’s 9" of firm to medium latex, then a middle layer of 3" medium-firmness with 20" cut off at the head, topped off by a 2" soft latex layer.
So the top 20" of my mattress is now 3" lower. Or rather, my body is 3" higher than my shoulder and head and arm. This takes pressure off my shoulder when I sleep on my side. Much better on the shoulder, and much less pain. Surprisingly, I thought I’d need a much taller pillow with this setup, but it’s not so.
The craziest thing about side sleeping is how the slightest movement of a leg can change the spine alignment and reflect through the neck and head, not to mention how much weight shift can occur in the hips. If I bend or straighten my knee a little, my hips can sink or float on the mattress a great deal, or at least it seems that way. If I bend more fully towards a fetal position the drooping reverses. It makes sense mechanically, at least at the hips, but it’s awfully difficult to understand the mechanics of the spine. The spine can twist and bend, even if only a little, but it adds up over its length. Which brings me to my head. I bend a little at the knees, the spine adapts, maybe it twists as if I rolled my top shoulder back, and all of a sudden I find my neck wants to pull my head down low, and my pillow’s now too tall.
So about those pillows, all my pillows are adjustable, mostly shredded material: buckwheat, wool, and memory foam. These pillow let me adapt the height and angle of my head as I change position. When I move my legs, that wonderful, cool, totally conformant buckwheat pillow acts like my head’s in a vice grip. All that pressure goes through my neck, and it hurts. Much as I love that buckwheat pillow, it’s much healthier to use the shredded memory foam. These can flex sideways, so instead of building pressure on my neck, my head moves, so there’s no pressure and no neck pain. While I can usually put up with the heat, I’m thinking of splitting a pillow so it’s shredded foam or latex on the bottom and buckwhat on the top. The thing that worries me is I notice it takes at least 3" of foam after it’s compressed to get enough sideways flexibility, so this hybrid pillow might end up too tall, about 6" or more.
One last thing about the split-level. When I sleep on my back, I feel like my head’s too high. That is, my body sinks more than my head. That’s been true with the firmest mattress (the one I bought after back surgery) and more so with less firm ones. So I was using a 3" buckwheat filled roll pillow under my neck and nothing under my head. I let out some of the filling to make it the perfect fit for me, and it’s now flexible enough to conform to and support my neck. Well, that was with the flat bed. With the split level, I can go back to a variety of pillows, all of which will be adjustable of course.
There’s one big downside to this split level thing. My lower arm has to be up high, with my elbow at least at shoulder level. I’ll continue to work on that.
I don’t expect any of this to fit anyone here, but hopefully it gives someone an idea, or maybe helps think a bit differently about their situation.