caffeine A stimulant compound found naturally in coffee, tea, cocoa (chocolate), and kola nuts (cola) and added to soft drinks, foods, and medicines. Caffeine can cause anxiety, insomnia, nervousness, and hypertension. Caffeine is a diuretic and increases urination. It can decrease a person’s ability to lose weight because it stimulates insulin secretion, which reduces blood…
Caffey disease An inflammatory bone disorder seen only in newborn and very young babies, characterized by swelling of soft tissues, irritability, fever, and paleness. Also known as infantile cortical hyperostosis.
calamine An astringent made from zinc carbonate or zinc oxide, customarily used in lotion form to treat skin problems or insect bites that cause itching or discomfort.
calcaneal spur A bony spur, also known as a heel spur, that projects from the back or underside of the heel bone (the calcaneus) and that may make walking painful. Calcaneal spurs are associated with inflammation of the Achilles tendon (Achilles tendinitis), and cause tenderness and pain at the back of the heel, which is…
calcaneocuboid joint The joint located in the foot between the calcaneus bone and the cuboid bone. It is a gliding type of joint. The ligaments that serve to support and strengthen this joint are called the capsular, dorsal calcaneocuboid, bifurcated, long plantar, and plantar calcaneocuboid ligaments.
calcaneus The heel bone, a more or less rectangular bone at the back of the foot. Also known as os calcis.
calcific bursitis Chronic inflammation of a bursa (bursitis) that leads to calcium deposits in the bursa. The calcification can occur as long as the inflammation is present. See also bursa; bursitis.
calcification The process of suffusing tissues with calcium salts.
calcified granuloma A node-like type of tissue inflammation that has a specific appearance under a microscope (granuloma) and contains calcium deposits. Because it usually takes some time for calcium to be deposited in a granuloma, it is generally assumed that a calcified granuloma is an old granuloma, or an old area of inflammation. For example,…
calcinosis An abnormal deposit of calcium salts in body tissues. Examples include the calcifications in the skin from scleroderma and in the muscle from polymyositis.
calcitonin A hormone produced by the thyroid gland that lowers the levels of calcium and phosphate in the blood and promotes the formation of bone. Bone is in a constant state of remodeling. Old bone is removed by cells called osteoclasts, and new bone is added by cells called osteoblasts. Calcitonin inhibits bone removal by…
calcium A mineral found mainly in the hard part of bones, where it is stored. Calcium is added to bone by cells called osteoblasts and removed from bone by cells called osteoclasts. Calcium is essential for healthy bones and is also important for muscle contraction, heart action, and normal blood clotting. Food sources of calcium…