Hi everyone, I'm after a bit of advice please?

Hi everyone, I'm after a bit of advice please? I have a partially torn achilles tendon which the docs won't do anything about unless it ruptures. It's getting more and more painful and I can't take pain meds other than paracetamol. I've been looking online and it says the best thing to try and build up strength is calf raises on the stairs but I also have osteoarthritis in my big toe joints which makes that exercise almost impossible...