To propagate Ti by stem cuttings you have to have the 'hardened off' part of the cane where the leaves have already fallen off. Then you cut the cane into pieces and lay them in a pan of soil half covered. This is called the buried cane method. The part of the Ti cane up where yours is broken probably will not root, it is the softer actively growing part. You can leave it alone, or, if you choose to cut it off, new shoots should sprout out of the cane just below where it gets cut off.
