What is a common physical examination finding in patients with prepatellar bursitis?

In cases of prepatellar bursitis, a primary physical examination finding is localized swelling over the bursa. This swelling occurs due to inflammation of the bursa, which is situated in front of the kneecap (patella). The bursa in this area can become irritated and filled with fluid, leading to an obvious and noticeable bulge.

This localized swelling is a hallmark sign that helps differentiate prepatellar bursitis from other knee joint pathologies. While tenderness and discomfort may also be present, the distinctive feature of localized edema specifically over the bursa is a key indicator of this condition.

Effusion of the joint may also be present in other knee conditions but is not specific to prepatellar bursitis. Similarly, while popping sounds during movement can occur in a variety of knee issues, they are not a characteristic finding in prepatellar bursitis. Tenderness on bending the knee might relate to other joint or ligament injuries rather than being specific to the inflammation of the bursa itself. Therefore, the localized swelling is what distinctly identifies prepatellar bursitis during a physical examination.