Does cold damp weather genuinely make an arthritic knee worse, or have I talked myself into it?

Bit of a strange one but it's been bugging me for years. My right knee tells me when the weather is turning. Two days of grey and damp and it aches deeper, feels heavier, and the first hundred yards in the morning are noticeably worse. My daughter, who is a scientist and enjoys this far too much, says it's confirmation bias and I only remember the times I was right.

The thing is I was right about last Tuesday and she still wouldn't concede.

So does anyone actually know? Is there something real happening in a worn joint when the pressure drops, or is it that I move about less when it's miserable out and the knee stiffens up because of that? Because those two explanations lead to completely different responses and I'd like to know which one I'm dealing with.

Mine is the same and I've stopped trying to justify it to anyone. Cold and damp, worse. Crisp and cold and dry, fine. Hot weather, best of the lot. If it's all in my head then my head has been running the same experiment for six years and getting the same answer.

Counter data point since everyone is agreeing with each other. I genuinely cannot tell. I've had two winters with this knee and the worst weeks have both been in June, after I'd done too much. For me it tracks what I did last week, not what the sky is doing.

Though I'll admit I'm on the bike most days regardless of the weather, so maybe I never sit still long enough to seize up.

petef58 said:

those two explanations lead to completely different responses

That's the sharpest bit of the question and I'd give you a boring answer: it's probably both, and only one half is under your control.

The honest state of things is that the weather idea has been studied a fair amount and the results have never come out cleanly. Some studies find a small link between symptoms and temperature or barometric pressure, others find nothing much at all, and the effects that do turn up are usually modest rather than the dramatic thing our knees report to us. I asked my surgeon this in a pre-op appointment, half expecting to be laughed at, and he said something I've repeated ever since: he hears it from patients constantly, he has no good mechanism to offer, and he isn't going to tell people their own knees are lying to them. So nobody sensible dismisses it, but nobody can show you the wiring either.

What is much easier to demonstrate is the second half of your list. A grey damp fortnight is a fortnight of shorter walks, more sitting, more time indoors, and an arthritic knee stiffens fast when it isn't used. Cold muscles are also less willing to do their job supporting the joint, so the same knee genuinely does feel worse first thing on a raw morning. That part is real and it is fixable, which is why I'd not spend much energy on winning the argument with your daughter and quite a lot on protecting your winter routine. Half the people posting here have discovered that their bad season was really an inactive season, and the site's rundown of what actually helps a worn knee short of surgery puts strengthening at the top of the list for exactly that reason.

For what it's worth, mine still aches before rain, replacement and all. About 1 in 5 people report the new knee never feels quite normal, and a weather-change ache is one of the things they mean. It didn't make me regret the surgery for a second.

Margaret is right about the inactive season. My worst winter was the one I spent being sensible and staying in. The next one I joined the pool sessions and it was a completely different three months, same weather.

We shifted our group walks to eleven in the morning through the winter instead of nine, and put a proper warm up on the front of them. Attendance went up and the number of people limping at the end went down. Make of that what you will, but the weather didn't change.

Been keeping a note since this thread, mostly out of spite towards my daughter. Weather, what I did the day before, how the knee was.

Early conclusion is annoying: the strongest pattern isn't the rain, it's the number of days in a row I've done nothing. The rain just happens to be what stops me. She hasn't seen the notebook yet and I'm in no hurry.