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.
People engaged in sports, adventure games, or an accident can experience swelling above the knee joint due to injuries to soft tissues like ligament strains, tendon injuries, muscle strains, cartilage and meniscus injuries. Injuries to the knee cap and soft tissues of the knee cap can cause swelling above the knee. Serious injuries like fractures or dislocations too can cause swelling above the knee. If the pain is very severe with inability to move the knee, then immediate medical attention should be sought.