It never occurred to me that my recent achilles trouble would be connected to 4y of letrozole. And possibly an earlier episode of wrist pain playing table tennis. Not had either before and went to physio for diagnosis and treatment. My feet feel like inflexible blocks of wood every morning. I have symptoms of plantar fasciatus from time to time. My ankles are tender, my heels were incredibly tender. My reading online and on this site suggest my discomforts are another side effect of letrozole. Calf raise exercises have helped. Ibuprofen gel does not seem to make much difference. Heat packs when I remember do help temporarily. Wedge (low) heels definitely help. I am now avoiding bare feet for too long, also flat shoes as much as possible (abandoned my ecco sandals) and have a tennis ball handy to roll under both feet, but sometimes agony to roll under the actual heel. There are some research articles on link between AIs and tendinopathies. I have temporarily (hope not permanently) stopped playing table tennis which I love. And walking is quite painful if too fast or too far. Walking on an inclined treadmill I think set off the acute achilles and heel pain. I feel from my reading that changing to a different AI will not help. I have not had an AI "holiday" as yet. I will be asking my GP about this side effect next week. I do not see oncologist for a few months. No medical person or allied health person had made the link between AIs and tendon problem. But I will certainly ask them.