I had a knee scope 5 weeks ago why cant i fully contract my quad?

Quad dysfx: Is the knee red? swollen? warmer than the opposite knee? These are signs of infection and/ or possible fluid on the knee It is not clear why the scope was done or what was noted but would follow up with the orthopedist and consider imaging to look for fluid and ask about infection, If not already ask about physical therapy to increase functionality and strength. f/u /w /MD