何謂背痛？ 背痛是美國最常見的醫療問題之一。背痛可能是連續鈍痛或突發的銳痛。背痛的病因可以是： 事故。 跌跤。 提舉重物。 隨著年齡的增長脊柱發生變化。 障礙或病症。 具體治療取決於疼痛的病因和症狀。可以做一些事情來改善健康狀況並降低出現慢性（長期）背痛的機率。
What is osteonecrosis? Your bones are made up of living cells that need a blood supply to stay healthy. In osteonecrosis, blood flow to part of a bone is reduced. This causes death of bone tissue, and the bone can eventually break down and the joint will collapse. Osteonecrosis can happen to any bone, but most often it develops in the ends of long bones, such as the: Thigh bone. Upper arm bone. Less often, the bones of the elbows, ankles, feet, wrists, and hands are affected. When the disease involves part of a bone in a joint, it can
What is back pain? Back pain is one of the most common medical problems in the United States. It might feel like a dull, constant ache or a sudden, sharp pain. Back pain can result from: An accident. A fall. Lifting something heavy. Changes that happen in the spine as you age. A disorder or medical condition. Treatment depends on the cause and symptoms of your pain. You can do things to improve your health and lower your chance of developing chronic (long-lasting) back pain.
What is Raynaud’s phenomenon? Raynaud’s phenomenon is a condition that causes the blood vessels in the hands and feet to narrow, decreasing blood flow. When this happens, parts of the body—usually the fingers and toes—become cold and numb, and change color (usually, to white or blue). An attack usually happens from exposure to cold or stress.
What is pemphigus? Pemphigus is a rare disease that causes blistering on many parts of the body, including the skin and the inside of the mouth, nose, throat, eyes, and genitals. In pemphigus, the immune system mistakenly attacks cells in the top layer of the skin.
What is fibromyalgia? Fibromyalgia is a long-lasting disorder that causes pain and tenderness throughout the body. It also can cause you to feel overly tired (fatigue) and have trouble sleeping. Doctors do not fully understand what causes fibromyalgia, but people with the disorder are more sensitive to pain.
What are polymyalgia rheumatica and giant cell arteritis? Polymyalgia rheumatica and giant cell arteritis are closely linked inflammatory disorders. Some people have one of the disorders while others develop both of them. Polymyalgia rheumatica causes muscle pain and stiffness in the shoulders, upper arms, hip area, and sometimes the neck. Giant cell arteritis causes inflammation of arteries, especially those on each side of the head, scalp, and the aorta (the large artery that carries blood from the heart) and its main branches. The main symptoms of this disorder are: Headaches. Scalp tenderness. Jaw pain. Problems with your eyes, which may