Can t stand up for more than 5 minutes; it feels like I will be falling down if I persist. I am 88 years old and in perfect physical condition; all tests (MRIs, blood etc) normal. I used to be quite active 5 months ago with my garden and then in a matter of a few months I am experiencing a weakness when standing. The only surgery I have had is knee surgery. They tell me I may have neurological issues?
Hello Thank you for using Chat Doctor . I read your question and understood your concern. I think you may have what we call orthostatic hypotension which is low blood pressure when you stand up, and you feel weak dizziness like fainting. Some patients after surgery develop this condition when they stay in bed lay down for some days in hospital and then when they start to stand and walk have signs like you. I suggest you to measure the blood pressure both sitting and standing position right way. If there is big deference it is orthostatic hypotension. If that is the case you need to Chat Doctor.  It may take few weeks or months, but it will go way.