When a bursa sac ruptures or becomes inflamed, the jelly-like fluid of the bursa swells and puts pressure on the adjacent parts of the knee, according to the American Academy of Orthopedic Surgeons. Symptoms of this condition, known as prepatellar bursitis, include pain with activity, rapid swelling on the front of the kneecap and tenderness and warmth to the touch. The potential for infection could lead to excess fluid production and redness of the infected area.
An orthopedic surgeon or emergency room doctor can choose to perform a variety of tests on a patient's knee that is affected by prepatellar bursitis, notes the American Academy of Orthopedic Surgeons. Such tests may include X-rays, computed tomography scans and magnetic resonance imaging scans. If the threat of infection is deemed an immediate issue by a medical professional, aspiration may be performed.
Aspiration is the process of drawing fluid with a needle from the affected area to provide a sample for further lab testing, explains the American Academy of Orthopedic Surgeons. Barring infection, certain nonsurgical health care strategies are usually effective for healing, including substituting strenuous activity with low impact exercises; applying ice at regular intervals three to four times per day; elevating the knee; and taking anti-inflammatory medication such as naproxen or ibuprofen.