Originally Posted by
bocastephen
OP: Can you come back and post additional details about your trip? Airline, route, date, etc.
I agree with this part - the more we know, the better the advice we can provide.
Originally Posted by
bocastephen
If you are not financially compensated for the fare difference, I suggest you take the airline to small claims court (if you're in the US) and sue for the fare difference and additional compensation for your physical discomfort.
If you're still suffering physical discomfort from the trip, and can prove you always buy business or first on long haul flights because of the physical comfort issues, you could also consider hiring a lawyer and taking the airline to regular court, suing for punitive damages as well for your 'pain and suffering.'
Please be aware that if you are based anywhere other than the US, the first part of this may or may not work, and the second will get you laughed out of court.