elbow: the joint of a mammal or bird that corresponds to the human elbow
joint: (anatomy) the point of connection between two bones or elements of a skeleton (especially if it allows motion)
hepatitis c: a viral hepatitis clinically indistinguishable from hepatitis B but caused by a single-stranded RNA virus; usually transmitted by parenteral means (as injection of an illicit drug or blood transfusion or exposure to blood or blood products)