Post-Total knee replacement, how to work on gait, is it alignment issue?

Knee pain does not occur after one day. Some people learn the wrong gait and feel like the wrong gait is normal. After surgery, they must learn the correct ways. Therapists will come in to teach them to walk properly and re-strengthen the muscle. When I see these patients walk in my clinic normally, I will sometimes not know they have done a TKR. The whole purpose of knee replacement is to restore the mechanics of walking and quality of life.