I know two pilots who suffer slight to moderate back discomfort and had their medical examiner and family doctors write to the company recommending a backback rather than the hand carry or roller case (roller case did not fit in the flightdeck next to the left and right seats). It was accepted after pressure from ALPA and the company doctor. Give it a try, hell why you are at it, get the doctor to write a note that you need to have a shot of rum every few hours to calm your nerves too!!
Company management hates doctors recomendations that run contrary to what the company wants!
Ciao
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