jogger’s nails Very common, small, semicircular white spots on the toenails. These spots result from injury to the base (matrix) of the nail, a structure under the visible nail where the cells that make up the visible nail are produced. The injury responsible for these white spots on the nails can be due to athletic…
joint The area where two bones are attached for the purpose of permitting body parts to move. A joint is usually formed of fibrous connective tissue and cartilage. Joints are grouped according to their type of motion: ball-and-socket joint; hinge joint; condyloid joint, which permits all forms of angular movement except axial rotation; pivot joint;…
joint, AC Acromioclavicular joint.
joint, acetabular The hip joint. The acetabulum is the cup-shaped socket of the hip joint, and it is a key feature of the pelvic anatomy. The upper end of the femur (thighbone) fits right into the acetabulum, articulates with it, and thereby forms the largest ball-and-socket joint in the human body.
joint, acromioclavicular See acromioclavicular joint.
joint, atlas and axis See atlantoaxial joint.
joint aspiration See arthrocentesis.
joint hypermobility syndrome See hypermobility syndrome.
joints of the body, principal The principal joints of the human body include the following: acromioclavicular ankle (tibia-fibula and talus) atlantoaxial atlantooccipital calcaneocuboid carpometacarpal elbow (humerus, radius, and ulna) femur and tibia hip bone and femur intercarpal (proximal carpal, distal carpal, and the two rows of carpal bones with each other) intermetacarpals intermetatarsals interphalangeal intervertebral…
Journal of the American Medical Association See JAMA.
jugular vein One of the veins in the neck that drain blood from the head, brain, face, and neck, and then convey it toward the heart. There are an external jugular vein and an internal jugular vein on each side of the neck. The jugular veins are particularly prominent during congestive heart failure. When the…
jugular vein, external The more superficial of the two jugular veins on each side of the neck. The external jugular vein collects most of the blood from the outside of the skull and the deep parts of the face. It lies outside the sternocleidomastoid muscle, passes down the neck, and joins the subclavian vein. See…