osteomalacia

OSTEOMALACIA

.osteomalacia [os″te-o-mah-la´shah]softening of the bones, resulting from impaired mineralization, with excess accumulation of osteoid, caused by a vitamin D deficiency in adults. The deficiency may be due to lack of exposure to ultraviolet rays, inadequate intake of vitamin D in the diet, or failure to absorb or utilize vitamin D, inherited impairement or reabsorption of phosphate, conditions that lower absorption of fat- soluble vitamins,liver or kidney dse,& malfunctioning parathyroid gland. X-ray examination reveals transverse, fracture-like lines in the affected bones and areas of demineralization in the matrix of the bone. As the bones soften they become bent, flattened, or otherwise deformed. Treatment consists of administration of large daily doses of vitamin D and dietary measures to insure adequate calcium and phosphorus intake. adj., adj osteomala´cic.

Causes, incidence, and risk factorsThe softer bones in osteomalacia have a normal amount of collagen, which gives the bones its structure. However, they lack the proper amount of calcium. In children, the condition is called rickets and is usually caused by low levels of vitamin D.Other conditions that may lead to osteomalacia include:•Not enough vitamin D in the diet•Not enough exposure to sunlight, which produces vitamin D in the body•Malabsorption of vitamin D by the intestines

Factors that reduce formation of vitamin D in the body include:•Having very little exposure to sunlight•Shorter days of sunlight•Smog•Using very strong sunscreen

The elderly and people who do not drink milk are at increased risk for osteomalacia.Other conditions that may cause osteomalacia include:•Cancer•Disorders of vitamin D metabolism•Kidney failure and acidosis•Lack of enough phosphates in the diet•Liver disease•Side effects of medications used to treat seizures

Symptoms•Bone fractures that happen without a real injury•Muscle weakness•Widespread bone pain, especially in the hipsSymptoms may also occur due to low calcium levels. These include:•Numbness around the mouth•Numbness of the arms and legs•Spasms of the hands or feet

Diagnostic tests•Blood tests will be done to check vitamin D, creatinine, calcium, and phosphate levels.•Bone biopsy will show bone softening.•Bone x-rays and a bone density test can help detect pseudofractures, bone loss, and bone softening.Other tests may be done to find out if a kidney problem or other disorder is causing the problem. These tests include:•ALP (alkaline phosphatase) isoenzyme•PTH (Parathormone)

TreatmentTreatment may involve vitamin D (25 hydroxycholecalciferol), cod liver oil, calcium, and phosphorus supplements taken by mouth. People who cannot properly absorb nutrients through the intestines may need larger doses of vitamin D and calcium.People with certain conditions may need regular blood tests to monitor blood levels of phosphorus and calcium.Expectations (prognosis)>few weeks to about 6 months.ComplicationsSymptoms can return.

osteoporosis

Osteoporosis is a disease in which bones become fragile and more likely to fracture. Usually the bone loses density, which measures the amount of calcium and minerals in the bone.

Causes, incidence, and risk factorsOsteoporosis is the most common type of bone disease.About half of all women over the age of 50 will have a fracture of the hip, wrist, or vertebra (bone of the spine) during their lifetime.

• Reduced total bone mass, >resorption than formation• Gradual collapse of the vertebrae =progressive kyphosis

“Dowager’s Hump”

Calcium is one of the important minerals needed for bones to form. If you do not get enough calcium and vitamin D, or your body does not absorb enough calcium from your diet, your bones may become brittle and more likely to fracture.

Sometimes bone loss occurs without any cause. White women are more likely to have bone loss. Sometimes the tendency to have bone loss and thin bones is passed down through families.A drop in estrogen in women at the time of menopause and a drop in testosterone in men is a leading cause of bone loss. Other causes of bone loss include:•Being confined to a bed•Certain medical conditions•Taking certain medicationsOther risk factors include:•Absence of menstrual periods (amenorrhea) for long periods of time•A family history of osteoporosis•Drinking a large amount of alcohol•Low body weight•Smoking

SymptomsThere are no symptoms in the early stages of osteoporosis. Many times, people will have a fracture before learning that they have the disease.Pain almost anywhere in the spine can be caused by fractures of the bones of the spine. These are called compression fractures. They often occur without an injury. The pain may occur suddenly or slowly over time.There may be a loss of height (as much as 6 inches) over time. A stooped posture or kyphosis (also called a "dowager's hump") may develop.

Diagnostic testsBone mineral density testing (most often with a DEXA scan) measures your bone mineral density. Your health care provider uses this test to:•Diagnose bone loss and osteoporosis•Predict your risk of future bone fractures•See how well osteoporosis medicine is workingA spine or hip x-ray may show fracture or collapse of the spinal bones. However, simple x-rays of other bones are not very accurate in predicting whether you are likely to have osteoporosis.You may need other blood and urine tests if your osteoporosis is thought to be due to a medical condition, rather than simply the usual bone loss seen with older age.

TreatmentTreatment for osteoporosis may involve:•Lifestyle changes, such as diet and exercise•Taking calcium and vitamin D•Using medicationsMedications are used to strengthen bones when:•Osteoporosis has been diagnosed by a bone density study, whether or not you have a fracture.•A bone fracture has occurred and a bone density test shows that you have thin bones, but not osteoporosis.Medicines used to treat osteoporosis include:•Bisphosphonates (the main drugs used to prevent and treat osteoporosis in postmenopausal women)•Estrogens, teriparatide, raloxifene, and calcitonin

Exercise plays a key role in preserving bone density in older adults. Some of the exercises recommended to reduce your chance of a fracture include:•Weight-bearing exercises -- walking, jogging, playing tennis, dancing•Free weights, weight machines, stretch bands•Balance exercises -- tai chi, yoga•Rowing machines

Avoid any exercise that presents a risk of falling, or high-impact exercises that may cause fractures in older adults.Your body needs calcium and vitamin D to keep your bones strong. Vitamin D helps your body absorb calcium.•Adults under age 50 should have 1,000 mg of caclium and 400 - 800 IU of vitamin D daily.•Women ages 51 to 70 should have 1,200 mg of calcium and 400 - 800 IU of vitamin D a day; men ages 51 to 70 need 1,000 mg of calcium and 400 - 800 IU of vitamin D a day.•Adults over age 70 should get 1,200 mg of calcium and 800 IU of vitamin D daily. •Your doctor may recommend a calcium supplement.•Follow a diet that provides the proper amount of calcium and vitamin D.Stop unhealthy habits:•Quit smoking, if you smoke.•Limit your alcohol intake. Too much alcohol can damage your bones, and put you at risk for falling and breaking a bone.

It is critical to prevent falls. Avoid sedating medications and remove household hazards to reduce the risk of fractures. Make sure your vision is good. Other ways to prevent falling include:•Avoid walking alone on icy days•Leave lights on at night so you can see better when walking around your house•Remove slippery rugs from your house•Use bars in the bathtub, when needed•Wear well-fitting shoesThere are two surgeries used to treat severe, disabling pain from spinal fractures due to osteoporosis:•Kyphoplasty•Vertebroplasty

Expectations (prognosis)Medications to treat osteoporosis can help prevent future fractures, but spine bones that have already collapsed cannot be reversed.Some people with osteoporosis become disabled from weakened bones. Hip fractures are one of the main reasons people are admitted to nursing homes.PreventionCalcium is essential for building and maintaining healthy bone. Vitamin D is also needed because it helps your body absorb calcium. Following a healthy, well-balanced diet can help you get these and other important nutrients throughout life.Other tips for prevention:•Avoid drinking excess alcohol•Don't smoke•Get regular exerciseA number of medications are approved for the prevention of osteoporosis.

PAGET’S DISEASE

Paget's disease is a chronic condition of bone characterized by disorder of the normal bone remodeling process. Normal bone has a balance of forces that act to lay down new bone and take up old bone. This relationship (referred to as "bone remodeling") is essential for maintaining the normal calcium levels in our blood. In bone affected by Paget's disease, the bone remodeling is disturbed and not synchronized. As a result, the bone that is formed is abnormal, enlarged, not as dense, brittle, and prone to breakage

Causes, incidence, and risk factors

The cause of Paget's disease is unknown, although it might have to do with genes or a viral infection early in life.

The disease occurs worldwide, but is more common in Europe, Australia, and New Zealand.

In people with Paget's disease, there is an abnormal breakdown of bone tissue, followed by abnormal bone formation. The new bone is bigger, but weaker and filled with new blood vessels.

The disease may only be in one or two areas of the skeleton, or throughout the body. It often involves bones of the arms, collarbones, leg, pelvis, spine, and skull.

Diagnostic testsTests that may indicate Paget's disease include:•Bone scan•Bone x-ray•Elevated markers of bone breakdown (for instance, N-telopeptide)•Elevated serum alkaline phosphatase

This disease may also affect the results of the following tests:•ALP (alkaline phosphatase) isoenzyme•Serum calcium

TreatmentPatients who may not need treatment include those who:•Only have abnormal blood tests•Have no symptoms and no evidence of active diseasePatients with Paget's disease who are commonly treated include patients who have:•Certain bones, such as weight-bearing bones, involved, or bony changes that are getting worse quickly (treatment can reduce the risk of fractures)•Deformities•Pain or other symptoms•Problems with the skull, to prevent hearing loss

Drug therapy helps prevent further bone breakdown. Currently, there are several classes of medications used to treat Paget's disease. These include:• Bisphosphonates -- These drugs are the first

treatment, and they help increase bone density. They may be taken by mouth or given through a vein (intravenously) less often. 

• Calcitonin -- This hormone is involved in bone metabolism. It may be given as a nasal spray (Miacalcin), or as an injection under the skin (Calcimar or Mithracin)

• Acetaminophen (Tylenol) or nonsteroidal anti-inflammatory medications (NSAIDs) may also be given for pain. Orthopedic surgery may be needed to correct a deformity in severe cases.

Expectations (prognosis)Disease activity and symptoms can generally be controlled with current medications. A small percentage of patients may develop a cancer of the bone called osteosarcoma. Some patients will need joint replacement surgery.

Complications•Bone fractures•Deafness•Deformities•Heart failure•Paraplegia•Spinal stenosis