My left hip was replaced 6 months ago and my recovery was going great until 2 weeks ago. While walking I got a pain on the outside of my left knee. The pain comes and go, only occurs when I walk and can be felt anywhere on the outside of my leg from the butox to the shin. It also hurts when I stand from sitting and take the first steps. Until this happened I had completed my physical therapy and had a started participating in an exercise class. Is the pain from the hip replacement loosening or could be muscular or tendititis from over exercising too early?