Magnesium is needed for the metabolism of potassium and calcium and for the mobilization of calcium from bones. Phosphorus plays and important role in the development and maturation of the bone. Its chief role in bone resorption, mineralization and collagen synthesis makes it essential in calcium homeostasis (Michael's). Diseases and disorders of the skeletal system include leukemia, bursitis, osteoporosis, sprains, fractures, spina bifida, scurvy, arthritis, scoliosis, talipes equinovarus or clubfoot, tendonitis, kyphosis and poliomyelitis (Family Shock 2001). Leukemia is also called cancer of the blood where abnormally large numbers of white blood cells multiply at an uncontrolled manner so that they interfere with the body's production of red blood cells. The cause is still unknown. Bursitis is a painful condition, which most commonly affects the hips and the shoulders. The bursa is inflamed. The bursa consists of small fluid-filled bags, which lubricate surfaces so that muscles can move over bones. The inflammation usually results from over-activity of an arm or leg. Osteoporosis is a disease caused by the loss of bone tissue. The cancellous bone is drained of calcium, becomes thinner or disappears altogether. A sprain is an injury to a ligament or tissue, which covers a joint. Most sprains occur from sudden stretches or tissue tears of the ligaments. Sprains are often very painful. The injured part usually swells and becomes "black and blue." A fracture is a broken bone. Spina bifida is a spinal defect, which occurs right at birth. In this condition, the spinal cord does not form properly around the vertebrae so that the skin cannot form around it. The cause is an error in the development of the embryo, which occurs about a month from the start of pregnancy. The use of alcohol or certain medications, exposure to extreme heat, or genetic factors may be responsible for the defect. Scurvy is a disease caused by the lack of Vitamin C or Ascorbic Acid in the diet. There is poor wound healing. Bruises come easily and the mouth and gums become sore. The gums also bleed, the teeth loosen, appetite becomes poor, the...

Arthritis covers more than 100 diseases of the joints. All types involve pain, stiffness and swelling of the joints. Osteoarthritis is a degenerative joint disease, where the joint wears out. It occurs frequently in the elderly, but it can also develop when a joint is repetitiously injured. The most affected joints are those in the hands, hips, knees, lower back and neck. Scoliosis is described as a side-to-side curve of the spine, which becomes visible during adolescence. The cause is still unknown, but it affects girls more than boys. Talipes equinovarus or clubfoot is an abnormal condition of the foot, usually discovered or present at birth. The foot is bent downward and inward, so that the child or person can walk only on his toes, heels or on the outside of his feet. Tendinitis or rheumatism is the stiffness or pain in the muscles or the joints. Kyphosis or hunchback is a forward bending of the spine, caused by anything, which deforms the bones in the upper part of the spine. Diseases, which cause kyphosis, include tuberculosis, syphilis, and rheumatoid arthritis. And poliomyelitis or polio is a serious disease, caused by the polio virus. This virus usually attacks the nerve cells of the brain and the spinal cord and causes paralysis. At first, the sufferer shows only slight symptoms, such as fever, headache, sore throat, and vomiting, which disappear after a day (Family Shock).
Bibliography

Discovery Kids. Skeletal system. Discovery Communications, Inc., 2000. Retrieved May 30, 2007 at http://yucky.discovery.com/flash/body/pg000124.html

Family Shock. Diseases and Disorders. The Shock Family, December 21, 2001. Retrieved May 30, 2007 at http://www.shockfamily.net/sksleton/DISEASE.htmL

Michael's. Skeleton Factors. Michael's Naturapathic Programs: Inner Health Group, Inc., 1996 Retrieved on May 30, 2007 at http://www.michaelshealth.com/pdf/skeletalfactors.pdf

ThinkQuest. Skeletal System. Think Quest USA: Oracle Education Foundation, 1999. Retrieved on May 30, 2007 at http://library.thinkquest.org/5777/sked.htm