Strange things may happen to the old when growth and decay are juxtaposed in the same body.
This Dioscorea hemicrypta stem is growing roots in the air from the wall of the caudex, well above the ground. There is probably nothing wrong with the existing collection of roots in the ground, but the decay in the aged bark may have suggested to the meristem that there is earth here into which a few more roots may be launched.
Who knows, maybe they reach the ground and add to anchoring, absorption of moisture and nutrients, as well as vascular transport in years to come. Maybe even prolong the plant's already long life.