Bone healing

diagnosis

Bone fractures are diagnosed with X-rays. CT (computerized tomography) and MRI (magnetic resonance imaging) scans may also be used. Broken bones heal by themselves; the aim of medical treatment is to make sure the two pieces are lined up correctly. Subsequent X-rays are taken to monitor the bone's healing progress.
X-ray: X-rays are low doses of radiation that create an image of a body part, organ, or bodily system on film paper or fluorescent screens. X-rays show the alignment of the spine and may reveal degenerative joint disease, fractures, or tumors.
Computed tomography (CT) scan: Computerized tomography (CT) scan is an X-ray that uses computer technology and can be enhanced with the injection of a contrast dye into a vein. CT scans allow for multiple X-rays to be taken from different angles in the body where the pain is located to create a three-dimensional image of internal body structures. CT is used to show abnormalities in bones and soft tissue. CT scan can be used for individuals who are unable to tolerate magnetic resonance imaging (MRI).
Magnetic resonance imaging (MRI): Magnetic resonance imaging (MRI) tests uses a powerful magnet to produce images on a computer screen and film. MRI scans provide clear images of disc deterioration, pathologies of the spinal cord, spinal stenosis, herniated discs, spinal tumors, bone fractures, and abnormalities in nerves and ligaments. MRIs are conducted in a small, confined area and some individuals may find this uncomfortable. Some individuals may have to be sedated using a mild sedative such as alprazolam (Xanax®) or lorazepam (Ativan®). If the individual is sedated, transportation should be organized using a family member or friend.

signs and symptoms

The symptoms of a bone fracture depend on the particular bone and the severity of the injury, but may include pain, swelling, bruising, deformity, and inability to use the limb for varying periods of time.

complications

Every fracture carries the risk of failing to heal and resulting in a non-union, when a bone does not heal. Most non-unions require surgery. Some of the causes of non-union of a bone fracture includes: infection, inadequate blood supply to the bone, and incorrect splinting of the fracture.
Blood loss: Bones have a rich blood supply and a bad break can result in substantial blood loss. The circulatory system extends into bones, directly supplying the bone cells and bone marrow. Blood cells are formed within bone marrow. The bone marrow contains special cells called stem cells, which produce the body's red blood cells and platelets. Red blood cells carry oxygen to the body's tissues, and platelets help with blood clotting when a person has a cut or wound.
Injuries to organs: Injuries to organs such as the brain (in the case of skull fractures) or chest organs (if a rib breaks) can occur.
Infection: Bone infection (osteomyelitis) can occur in an open fracture. The bone may be exposed to fungi and bacteria that cause infection.
Growth problems: The fractured long bone of a young child may not grow to its intended adult length if the injury is close to a joint, since bone fuses when it heals. The growth plate is the area of developing tissue near the end of the long bones in children. Each long bone has at least one growth plate at each end. When growth is complete during adolescence, the growth plates are replaced by solid bone. Injuries may occur in children and adolescents. The growth plate is the weakest area of the growing skeleton and a serious injury to a joint is more likely to damage a growth plate than the ligaments around it. An injury that would cause a sprain in an adult can be a potentially serious growth plate injury in a young child.
Pain: Bone fractures may cause severe pain. Individuals should stay in close contact with their healthcare providers to ensure that their medications are properly managing the pain. In some cases, the medication or dosage may need to be changed.

causes and risk factors

The strength of the bones depends on their size and density. Bone density depends in part on the amount of calcium, phosphorus, boron, and other minerals that bones contain. When bones contain fewer minerals than normal, they are less strong and eventually lose their internal supporting structure. Genetic and environmental factors, such as diet and exercise, also affect bone strength.
Osteoporosis is a disease of the bones that makes them weak and prone to fracture. By their mid-30s, most individuals begin to gradually lose bone strength and more bone is lost than can be replaced. As a result, bones become less dense and structurally weaker. Osteopenia refers to mild bone loss that is not severe enough to be called osteoporosis, but that increases the risk of developing osteoporosis. As this occurs, bones lose calcium, phosphorus, boron, and other minerals and become lighter, less dense, and more porous. This makes the bones weaker and increases the chance that they might break. If not prevented or if left untreated, osteopenia can progress painlessly into osteoporosis until a bone breaks or fractures.
Risk factors for developing osteoporosis include:
Gender: Fractures from osteoporosis are about twice as common in women as they are in men. Although women are four times more likely than men to develop the disease, men also suffer from osteoporosis. Women start out with lower bone mass and tend to live longer, increasing their risk for developing osteoporosis. They also experience a sudden drop in estrogen at menopause that accelerates bone loss, as estrogen helps with bone formation. Slender, small-framed women are particularly at risk because they have relatively less bone mass to loose. Men who have low levels of the male hormone testosterone also are at increased risk. From age 75 years on, osteoporosis is as common in men as it is in women.
Age: Bones weaken during normal aging in a process called resorption. Bone resorption is the gradual loss of bone. As individuals age, whether male or female, there is an average loss of 0.5% bone mass every year after age 50. The result is an increase in bone fractures, such as hip fractures.
Ethnicity: Caucasians and Southeast Asians are at the greatest risk of osteoporosis, leading to an increase in bone fractures. African American and Latino men and women have a lower but still significant risk of osteoporosis-related fractures. It is estimated that around 40% of U.S. Caucasian women and 13% of U.S. Caucasian men aged 50 years and older will experience at least one fracture due to bone loss in their lifetime. It is also estimated that in the United States, 54% postmenopausal Caucasian women are osteopenic and 30% are osteoporotic, and by the age of 80, 27% of Caucasian women are osteopenic and 70% are osteoporotic.
Heredity: Having a parent or sibling (brother or sister) with osteoporosis puts the individual at a greater risk for developing osteoporosis and bone fractures, especially if the individual also has a family history of bone fractures. An individual with a family member who has osteoporosis has a 50-85% increased risk of developing osteoporosis.
Body frame size: Men and women who are exceptionally thin or have small body frames tend to have higher risk because they may have less bone mass to draw from as they age.
Smoking: The impact of cigarette smoking on bone health is not well understood. Smoking may cause a decrease in bone density, although it is unclear whether this is a direct result of the action of smoking or other factors that are generally attributable to smokers. Smokers are usually thinner than nonsmokers, tend to drink more alcohol, may be less physically active, and may have poor diets. Women who smoke also tend to have an earlier menopause than nonsmokers. These factors place many smokers at an increased risk for osteoporosis apart from their tobacco use.
In addition, most studies on the effects of smoking suggest that smoking increases the risk of having a fracture. Results have found that the longer an individual smokes and the more cigarettes consumed, the greater the risk of fracture in old age. Smokers who fracture bones may take longer to heal than non-smokers. Significant bone loss has been found in older women and men who smoke. Studies suggest that second-hand smoke exposure during youth may increase the risk of developing low bone mass. Also, women who smoke often produce less estrogen and tend to experience menopause earlier than nonsmokers. Smoking cessations appears to reduce the risk of low bone mass and fractures.
Estrogen levels: Estrogen helps to increase bone density. The longer a woman is exposed to estrogen, the lower her risk of osteoporosis. Women have a lower risk of osteoporosis if they have a late menopause or they began menstruating at an earlier than average age. A history of abnormal menstrual periods, experiencing menopause earlier than the late 40s, or having the ovaries surgically removed before age 45 without receiving hormone therapy may also increase the risk of developing osteoporosis.
Health conditions: Health conditions caused by hormone imbalances, such as hyperthyroidism (too much thyroid hormone), hyperparathyroidism (too much parathyroid hormone), and Cushing's syndrome (too much adrenal hormone) may increase the risk for osteoporosis because they interfere with the regulation of the hormones that regulate bone formation. Gastrointestinal disorders, such as celiac disease and Crohn's disease, which affect absorption of calcium and vitamin D, also increase the risk of osteoporosis. Early onset menopause brought on by the removal of the uterus (hysterectomy) and the complete removal of the ovaries (oophrectomy) are associated with osteoporosis.
Chronic alcohol abuse has been associated with decreased bone mineral density in and is commonly listed as a risk factor for osteoporosis. Prevalence of osteoporosis in alcoholics has been estimated at 28-52%. Excess consumption of alcohol reduces bone formation and interferes with the body's ability to absorb calcium.
Individuals who experience serious depression have increased rates of bone loss. Depression activates the sympathetic nervous system, which responds to impending danger or stress, causing the release of a chemical compound called noradrenaline that harms bone-building cells (osteoblasts).
Women and men with eating disorders, such as anorexia nervosa or bulimia, are at higher risk of lower bone density in their lower backs and hips. Eating disorders have significant physical consequences. Affected individuals can experience nutritional and hormonal problems that negatively impact bone density. Low body weight in females causes the body to stop producing estrogen, resulting in a condition known as amenorrhea, or absent menstrual periods. Low estrogen levels contribute to significant losses in bone density. In addition, individuals with anorexia often produce excessive amounts of the adrenal hormone cortisol, which is known to trigger bone loss.
Other problems, such as a decrease in the production of growth hormone and other growth factors, low body weight, calcium deficiency, and malnutrition, all contribute to bone loss in individuals with eating disorders. Weight loss, restricted dietary intake, and testosterone deficiency may be responsible for the low bone density found in males with eating disorders. Studies suggest that low bone mass (osteopenia) is common in people with anorexia and that it occurs early in the course of the disease. Girls with anorexia are less likely to reach their peak bone density and therefore may be at increased risk for osteoporosis and fracture throughout life.
Medications: Certain medications may decrease the body's ability to absorb calcium and may increase the risk of developing osteoporosis. Postmenopausal women who have had breast cancer are at an increased risk of osteoporosis, especially if they were treated with medications such as anastrozole (Arimidex®), letrozole (Femara®), and exemestane (Aromasin®), which suppress estrogen. Women treated with tamoxifen (Nolvadex®) do not seem to develop an increase in bone loss.
Diuretics, or medications that prevent buildup of fluids in the body, can cause the kidneys to excrete more calcium, leading to thinning bones. Diuretics that cause calcium loss include furosemide (Lasix®), bumetanide (Bumex®), ethacrynic acid (Edecrin®), and torsemide (Demadex®).
Long-term use of the blood-thinning medication heparin, the drug methotrexate (Rheumatrex®), some anti-seizure medications, such as phenytoin (Dilantin®), and aluminum-containing antacids, such as Amphojel®, can also lead to bone loss by decreasing the absorption of calcium and depleting calcium from the body.
Cholestyramine (Cholestin®), used to control blood cholesterol levels, may decrease calcium absorption and increase the risk of osteoporosis. Gonadotropin-releasing hormones (such as Lupron®) used for the treatment of endometriosis may also decrease calcium absorption and increase the risk of osteoporosis. Endometriosis is a condition in which the tissue that normally lines the uterus (endometrium) grows in other areas of the body, causing pain, irregular bleeding, and possible infertility.
Corticosteroids, such as prednisone (Deltasone®), may lead to osteoporosis. Approximately 30-50% of individuals taking corticosteroids long-term develop osteoporosis. Relatively short courses (two to three months) of more than 7.5 milligrams of prednisone (Deltasone®) can cause significant bone loss. The common long-term use of corticosteroids in conditions, such as rheumatoid arthritis, results in a dramatic increase in vertebral and ultimately hip fracture rates. Corticosteroids are used for inflammatory conditions including allergic reactions, skin diseases (psoriasis, hives), and breathing problems; certain cancers; blood disorders; eye problems; arthritis; digestive problems; and for hormone replacement.
Low calcium intake: A lifelong lack of calcium plays a major role in the development of osteoporosis. Low calcium intake contributes to poor bone density, early bone loss, and an increased risk of fractures. Many foods contain calcium, but dairy products are the most significant source. Milk and dairy products such as yogurt, cheeses, and buttermilk contain an efficiently absorbed form of calcium.
Lack of exercise: Exercise can increase bone density at any age. Muscle pulling on bone builds bone, so weight-bearing exercise builds denser, stronger bones. Children who are physically active and consume adequate amounts of calcium-containing foods have the greatest bone density.
Excess soda or coffee consumption: The link between osteoporosis and caffeinated sodas is not clear, but caffeine and phosphoric acid in the drinks may interfere with calcium absorption. Caffeine, also found in coffee and tea, is also a diuretic, which may increase mineral loss.