An IMF spokesman has hinted that banks will spend digital currencies in about 5 years from now. I don't know how that will prevent banks from getting broke.
The current Banking companies are on one of two sides, they are either with Bitcoin or not. Those who don't want to be involved with the digital currency like to keep it simple because when it comes to money nothing really lasts...the old-fashioned banker's already know this.
So yes, maybe in 5 years they might try to implement Digital Currency into their payment system...although I think that a bunch of the banks will try to start their own currency and will most likely fail.
Hopefully the Banks keep the price fluctuations volatile and random.