In addition to Energy Absorbing Foam (EAF) cushions in gliders, supporting 'spine shells' have been suggested to provide better lower-back protection at the base of parachutes, and better overall cockpit comfort. Some articles indicate that many slightly bumpy landings may cause cumulative back damage rivaling that of one hard landing. I've discovered that spine shells are sold for motorbike riders and other sports. Some look like they would be very suitable for a glider. There are many types available, easily found by Google, look for 'back protectors' or 'motorcycle armor' etc, or start with the first reference listed below. Has anyone tried using one of these commercial spine shells in a glider?

some references to spine shells and EAF cushions a
http://roadridermca.com/newsevents/g...acement-armor/
https://www.sunmatecushions.com/coll...pedic-cushions
Sailplane and Gliding Dec 2002-Jan 2003 issue, page 28
Sailplane and Gliding Oct-Nov 2012 issue, page 18
"Why you should fly with an energy absorbing safety cushion" BGA Safety Brochure