Incident #1:
At age 56 I fell in the garden. Compound fracture near the ankle, which also dislocated it. A LOT of nerve damage around the joint. Our home has 4 stoop steps to the front door, which is at a right angle to the stairs.
A friend built a temp ramp over the front stairs. Those ramps take a lot of length, more than one would think. It was 2 mos. before we could take it down.
Our master bedroom is downstairs, since our home is built on a downsloping lot. Even with a soft cast, I could not manage stairs. I was lucky; we had done a bit of remodeling on the main floor bathroom a decade before. The doorway and revised layout just fit a walker, so I could close the door and use the sink and toilet.
Forget the bathtub, it was a full month before I could get my leg (wrapped in a garbage bag) over the high edge of the tub. I've decided my personal h**l is being forced to take sink baths the rest of my life, LOL. When I finally got to take a shower, it was really hard to force myself to finally turn the water off. BLISS!!!!
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Incident #2
Actually, still ongoing. I developed BPPV in August 2020:
" Benign paroxysmal positional vertigo (BPPV) is one of the most common causes of vertigo — the sudden sensation that you're spinning or that the inside of your head is spinning. BPPV causes brief episodes of mild to intense dizziness. "
Really delightful....NOT. No pain, which is good. Nausea and 'seasickness' - except that you're on solid level ground and not even moving - not so wonderful.
No cure, either. Epley maneuver helps but I've found it more preventive (keeps it down to once or twice a day) than curative (doesn't seem to help during an attack).
Happily, one's body slowly adjusts and the attacks ease up in intensity and frequency. However, forget the blase Net definition of "duration 6-8 weeks on average" - mine didn't start to ease up until just a few weeks ago (mid-January 2021).
So again, I'm grateful there's a bathroom and bedroom on each floor. My office is on the main floor (LR/kitchen/DR open plan, a full bathroom and spare bedroom). If I get an attack of BPPV, no way can I manage stairs. Any handrail, cane, lift chair - all useless.
When you need to throw up.....you need to do it NOW.
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Our home is not universal access. It is manageable with a walker, although tiring. You never realize how many steps it takes to accomplish simple tasks, until the day arrives when your mobility is limited. When carrying anything from one place to another requires some planning in logistics.
We had been looking into senior living possibilities before the pandemic/lockdown. We're glad to be going through lockdown in our own home, which is certainly roomier and more comfortable than any place we saw.
But we have a number of older friends. Even the active healthy ones eventually get felled by the frailties of old age. Sorry, but you don't get to choose how you're going to spend the last few years of your life. All of us can plan all we want to, but sometimes.....life just happens.
Best to think ahead, as the OP is proposing, and do something to be prepared.