Patello-femoral pain syndrome is pain occurring behind the knee cap on doing activities such as going downstairs specifically, running or kneeling. The pain is often sharp and can stop you from doing the activity.
Biceps tendonitis is swelling of the biceps muscle tendon, which attaches to the front of the Shoulder. Biceps tendon damage may occur in people doing heavy physical activities such as construction workers. It is also common in body builders trying to lift heavier with their biceps exercises.