My PT pointed out to me that my foot wanted to turn out on the operated knee. Mechanically, the body wants to turn out the foot because it causes less
pain than trying to keep it straight. I've seen my own foot turn out when I'm resting, so I think it's just your body just naturally doing something so that you'll feel less pain. I've been really concentrating on hell-toe, etc and watching my right foot and reigning it in when necessary. Hope that helps you.