Thanks Jimbo for awakening us to what might happen, Speedy full recovery to you. I as with others, don't even mount the bike until the helmet is on. I read somewhere by one of the bike helmet mfg. that a helmet should be replaced every 5 years due to the breakdown of the materials caused by UV and other polluntants, makes sence to me, however some might say it's because of monetary gain by the companies. I'll choose to replace mine every 5 years, and if struck replace immediately.
Also, you bring up a great point about bungee straps, Please don't use them, there very dangerous when used on a bike. I and many makers of panniers (Beckman) recomends the use of half inch or one inch nylon straps with threaded buckles or the fastex type to secure the loads.
Again Jimbo, I pray you have a full recovery.