“Runner’s knee” is a blanket term to describe a number of conditions that cause pain at the front of the knee
A common complaint of athletes, Runner’s Knee is often the result of irritation in the soft tissues around the front of the knee. For some people, it is the result of their kneecap being out of alignment, which results in the wear and tear of the kneecap cartilage. This chronic wear and tear can eventually cause the cartilage to soften and break down, a condition identified as chondromalacia. As a result, the underlying bone and knee joint become irritated.
You may experience dull, aching pain around the front of the kneecap (the patella) where it connects to the lower end of the thigh bone (the femur). The pain may worsen when going up or down stairs, squatting, or kneeling.