The 'Succession' star was on hand Sunday in L.A. for the big award show, and folks immediately noticed he was using a cane to get around the red carpet. He didn't say anything about it in the moment -- but folks thought this was car crash-related.

Remember, Alan got into a nasty wreck out here in Hollywood when he lost control of his fancy electric truck and smashed through a wall a pizza parlor -- which caused a big scene and a lot of damage.

While Alan was seemingly uninjured at the time -- he did walk around with a knee sleeve in the days after ... and there, too, people thought he'd gotten a little banged up in the accident.

Now, here he is with another assist ... and the speculation has picked up all over again. Welp, we've got some answers -- and this isn't what it seems. Sources close to Alan tell TMZ his cane is actually helping him with an unrelated ailment he's been dealing with lately.

We're told Alan underwent a full knee replacement surgery just 3 and a half weeks ago -- this after suffering from arthritis for some time now. So, that's why he was using it.

If it wasn't clear from that ... no, this cane was not a fashion statement -- we're told AR absolutely needs it, and he's putting it to good use early and often. It's interesting (and miraculous) that he wasn't seriously hurt during the October wreck.