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.
One of the more common causes of pain in the back of the knee joint, specifically, is a popliteal synovial cyst, which is also known as a bakerâs cyst. This fluid-filled cyst at the back of the leg often forms in response to arthritis or other cartilage damage. The bulge creates a feeling of tightness behind the knee as well as stiffness and swelling and pain behind the knee and calf. For many, this pain intensifies when flexing or fully extending the leg.