Osteodystrophy (os-tee-oh-DIS-truh-fee) is a general term for defective or abnormal bone development. More to Know Bones are mostly made of a protein called collagen and a substance called calcium phosphate. This is why calcium is important for building and maintaining strong bones. But a number of conditions can affect the way a person's body breaks down and uses minerals like calcium and phosphorus to build bones. This can cause bones to form abnormally or break down too quickly. Osteodystrophy is usually a complication of kidney disease. In these cases, it is called renal osteodystrophy. Renal osteodystrophy can cause skeletal deformities, slowed growth, bone and muscle pain, knock-knees, and bowlegs. Sometimes liver disease can also cause osteodystrophy in a condition called hepatic osteodystrophy. Osteodystrophy is commonly associated with conditions like osteoporosis (decreased bone strength), osteitis fibrosa (soft, deformed bones), and osteomalacia (softening and weakening of bones due to a lack of vitamin D, calcium, or phosphate). Osteomalacia in children is called rickets. Treatment for osteodystrophy involves treating the condition that is affecting bone development and treating any symptoms as they appear. Keep in Mind Many of the conditions that cause osteodystrophy respond well to treatment with medications, supplements, and changes in diet. All A to Z dictionary entries are regularly reviewed by KidsHealth medical experts. Back to Articles Related Articles A to Z: Genu Valgum Learn about common childhood orthopedic conditions and conditions that affect the legs and knees. Read More A to Z: Genu Varum Learn about common childhood orthopedic conditions and conditions that affect the legs and knees. Read More Bones, Muscles, and Joints Without bones, muscles, and joints, we couldn't stand, walk, run, or even sit. The musculoskeletal system supports our bodies, protects our organs from injury, and enables movement. Read More Common Childhood Orthopedic Conditions Flatfeet, toe walking, pigeon toes, bowlegs, and knock-knees. Lots of kids have these common orthopedic conditions, but are they medical problems that can and should be corrected? Read More A to Z: Osteoporosis Mostly affecting older people, osteoporosis is a disease that weakens the bones, causing them to become brittle and easily fractured. Read More Bones, Muscles, and Joints Our bones, muscles, and joints form our musculoskeletal system and enable us to do everyday physical activities. Read More Calcium Your parents were right to make you drink milk when you were little. It's loaded with calcium, a mineral vital for building strong bones and teeth. Read More Calcium Milk and other calcium-rich foods help build strong, healthy bones. But most kids and teens don't get enough calcium. Here's how to make sure that yours do. Read More Minerals Just like vitamins, minerals help your body grow, develop, and stay healthy. Find out more about minerals in this article for kids. Read More Vitamins and Minerals Vitamins and minerals are nutrients that the body needs to work properly. They boost the immune system, promote normal growth and development, and help cells and organs do their jobs. Read More Your Bones Where would you be without your bones? Learn more about the skeletal system in this article for kids. Read More Note: All information is for educational purposes only. For specific medical advice, diagnoses, and treatment, consult your doctor. © 1995-2021 KidsHealth®. All rights reserved. Images provided by The Nemours Foundation, iStock, Getty Images, Veer, Shutterstock, and Clipart.com.