I’m knock-kneed as well. My physiotherapist was the one who pointed it out and said there was a noticeable shift, which may or may not resolve itself. Functionally, I can use my knee and I’m achingly close to getting full ROM back, so it’s just a matter of strengthening the area and seeing if that helps everything shift back into place.
The OS who I got the second opinion from – he, on the other hand, said the valgus shift was barely noticeable and if he wasn’t told which leg it was, he wouldn’t be able to tell.
So, I’d go with pain being an indicator that something needs checking out.