The passage below is from Being Mortal by Atul Gawande.
I met her grandmother Alice Hobson, who was seventy-seven at the time. She struck me as spirited and independent minded. She never tried to disguise her age... She wore simple, neatly pressed blouses and dresses, a bit of lipstick, and heels long past when others would have considered it advisable.
Here, I can not figure out the meaning of the italicized phrases. Under the context I just assume that grandmother was wearing heels worn out with usage. Am I right? If not, can you tell me what does it mean?