If it's two jagged edges on the break in the line, it does not mean that the airway is "unuseable" - if this were so, they'd remove! What it means is that
there is a gap in VOR (or other radionavigation aid) reception- at one point, you'll lose the VOR you're flying away from without having picked up the one you're flying to.

What do you do? Stay above the MEA, not the MRA or OROCA or MOROCA and maintain the heading which was keeping you on course until you pick up positive navigational coverage (meaning the needle is alive and indicating correctly) from the next navaid.