Don'tcha just love those reports

. I'm sorry that I wasn't much help when I read the info. How yours was written is usually the type of info. I find embedded before reading the closing comments ("Findings" or "Impressions") in mine.
Though I wasn't Rx'd a back support, I did try something that helped that my PT had suggested, and it didn't cost anything: He told me to take a towel and roll it up and use it when sitting at, i.e., a desk or in a chair.
I don't think that that would help when using your w.chair, though. I can visualize how a soft support could make it more bearable. For the w.chair, I would think that it's important to also find one (soft support) that doesn't decrease the space needed for the sitting "range" - not sure what to call it but the area needed from the bum to upper legs support.
When I travel overnight, I've learned to sleep (at an incline) with a king-size pillow under my back (from my shoulders to where the L-spine meets the S-spine) - otherwise, I get no sleep. I usually take along a couple pillows from home (since I know those work for my head) and a couple of throw blankets, which I use for x-tra cushioning on top of x-tra blankets I request.
If the bed isn't well-padded (soft), it may as well be the floor, since there isn't a comfy position.
I understand how you feel

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One thing that I loved was the aqua-therapy I had several years ago at PT. I'm working on getting easier access for my Jacuzzi.
Has your PT suggested aquatics? Just to be able to get the pressure off your nerves and having a time where you may be able to move a little more freely might bring you some relief.
Please ... don't be a stranger

... I'm interested in how you're doing and feeling. Too, when you find ideas that might help, those would also be great to know

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".... This world wasn't built for people in wheelchairs ...."
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