Check valve on toilet leg?

I have had the waste line that leaves the house fracture twice in the last three years, the breaks were both within ten inches from where they exit thru the foundation wall. On both occasions I was in the shower on the second floor of the house when this has occurred and of course upon coming downstairs I find the hardwoods and carpet in the family room flooded with (well, you know the smell). The culprit is the powder room toilet, it's the lowest waste line on the first floor. Water seeps from both the bottom of the bowl (wax ring) and over flows the rim of the bowl, until the interior waste lines clear. My question is, is it feasible to cut in a check valve on the toilet waste leg prior to it joining the main drain line. I realize that if this happens again the waste lines will back up but hopefully manifest this in the sinks and laundry tubs without ruining the hardwoods and carpet and the basement. Is a check valve on the toilet leg even possible considering the solid waste flow?

Thanks in advance for any suggestions.

Jeff