A joint was a connection between the bones in a body. Arthritis and rigor mortis were medical conditions affecting the joints. One of the symptoms of the early stages of the phage was excruciating joint pain. (VOY: "Faces") In 2372, Meso'Clan was hit by a plasma charge rigged by Miles O'Brien. It missed his femoral artery, but destroyed his knee joint. (DS9: "Hippocratic Oath") One of the medical tasks Julian Bashir thought about to perform while trapped on Ajilon Prime was a lateral incision across the thigh joint of a patient. (DS9: "Nor the Battle to the Strong")