hypophosphatasia

Your bones help you move, give you shape and support your body. They are living tissues that rebuild constantly throughout your life. During childhood and your teens, your body adds new bone faster than it removes old bone. After about age 20, you can lose bone faster than you make bone. To have strong bones when you are young, and to prevent bone loss when you are older, you need to get enough calcium, vitamin D, and exercise. You should also avoid smoking and drinking too much alcohol.

Bone diseases can make bones easy to break. Different kinds of bone problems include:

• Low bone density and osteoporosis, which make your bones weak and more likely to break
• Osteogenesis imperfecta makes your bones brittle
• Paget's disease of bone makes them weak
• Bones can also develop cancer and infections
• Other bone diseases, which are caused by poor nutrition, genetics, or problems with the rate of bone growth or rebuilding

NIH: National Institute of Arthritis and Musculoskeletal and Skin Diseases

Metabolism is the process your body uses to get or make energy from the food you eat. Food is made up of proteins, carbohydrates, and fats. Chemicals in your digestive system break the food parts down into sugars and acids, your body's fuel. Your body can use this fuel right away, or it can store the energy in your body tissues, such as your liver, muscles, and body fat.

A metabolic disorder occurs when abnormal chemical reactions in your body disrupt this process. When this happens, you might have too much of some substances or too little of other ones that you need to stay healthy. There are different groups of disorders. Some affect the breakdown of amino acids, carbohydrates, or lipids. Another group, mitochondrial diseases, affects the parts of the cells that produce the energy.

You can develop a metabolic disorder when some organs, such as your liver or pancreas, become diseased or do not function normally. Diabetes is an example.

Osteogenesis imperfecta (OI) is a genetic disorder in which bones fracture (break) easily. Sometimes the fractures happen for no known reason. OI can also cause weak muscles, brittle teeth, a curved spine, and hearing loss. OI is caused by one of several genes that aren't working properly. When these genes don't work, it affects how you make collagen, a protein that helps make bones strong.

OI can range from mild to severe, and symptoms vary from person to person. A person may have just a few or as many as several hundred fractures in a lifetime.

There is no specific test for OI. Your doctor uses your medical and family history, physical exam, and imaging and lab tests to diagnose it. Your doctor may also test your collagen (from skin) or genes (from blood). There is no cure, but you can manage symptoms. Treatments include exercise, pain medicine, physical therapy, wheelchairs, braces, and surgery.

NIH: National Institute of Arthritis and Musculoskeletal and Skin Diseases