There isn't any remedy for this type of physical damage (don't coat or paint the wood with anything). All you can do for now is to wait and see how those stems leaf-out in spring. If they resume normal growth, you probably don't need to worry about it, and the indentation will become less obvious in future years as the main stems expand in girth. If instead they seem to have died back due to the constriction, then prune off all dead (leafless) wood once all other growth has emerged, so it's more clear what branches have died back. Even on healthy figs, growth might emerge from the base of the plant before emerging on the branch tips, so give it some time (well into spring...probably May) to see how it fares. Worst-case, if there's lot of dieback that needs to be cut down, an established plant (which this appears to be) should regrow new branches from the base of the plant, though it might take a year or more until they are large enough and ready to bear fruit.

Miri