Egypt's second faith is Coptic Christianity. Copts are heirs of an ancient Christian rite. Coptic Christianity was the predominant religion in Egypt until the 10th century when a lot of Christians diverted to Islam. Christianity itself was brought in Egypt by St. Mark in the middle of the first century AD.
Other possible causes of swelling behind the knee include abscesses (infections); tumors of the skin, soft tissue, or bones; bleeding; deep venous thrombosis (blood clot in the deep veins of the legs); or deformity of the joint after a fracture of any of the bones of your knee joint.
Bursitis - Swelling of the small, fluid-filled sacs that separate your knee bones from nearby muscles and tendons. Tumors - Both cancerous and benign masses sometimes infiltrate the knee. Symptoms. You might have water on the knee if you notice: Swelling. The skin around the kneecap looks and feels puffy compared to the other knee. Stiffness. Range of motion decreases. The leg is difficult to completely bend or straighten. Depending on the cause, you might also notice instability, clicking, or locking of the knee. Pain.