I have had knee pain for a month now, I am male, 24 years of age and active as a fitness instructor so I am constantly on the move. Pain is located in left leg, right under knee cap, very localized, happens when I go up stairs and when i completely straighten knee (lock it out). Can be described as pricking sensations or pressure. I have done no weight training for 2 weeks, pain remains the same. Also no lateral pain or loss of stability.