Patella tendinitis "jumpers knee" is not very difficult to get rid of if you know what to do. Basketball players get it all the time and treat it successfully. Years ago I had it badly while playing both basketball and tennis. Also, I was practicing my serve alot too and got it on my left knee which I would land on when serving. Because of how severe it was, for once I did the smart thing and got professional help from a physical therapist. Besides showing you the proper stretches and strengthening exercises to do, they use ultrasound to really speed up recovery. I simply followed their advice and was back on the court in three weeks. Have not had a problem sense with my knee. How it started I think, is I never stretched my quads-bring foot up to butt behind you which also stretches your patella tendon. This is when I learned the true value of proper warm up and stretching and not hesitating to seek professional physical therapist if a problem is severe enough that rest , ice, ect. won't cure. Most "inflamed tendons" in elbow, shoulder, knee, ect. usually start do to lack of proper warm up and stretching, and too much stress placed on the tendon do to lack of strength in muscles surrounding the tendon. Your also vulnerable if you increase your workout load through extra practice and playing, which causes more force than the tendon is used to. If the inflamation is mild -rest, ice, advil,stretch, and strengthen muscles around the tendon. If pain is severe, or doesn't go away after doing the above for a few weeks be smart and see a physical therapist. Otherwise, the problem lingers for months and you will be helplessly posting and reading messages on the internet. From my experience, most tennis players who are constantly getting injured do not stretch properly, nor lift weights, and when they do get hurt have no clue what to do, and keep playing through the pain without treatment, only making it worst and chronic!