As people get older beyond middle age their bones start to become weaker and more brittle. This the result of a process called osteoporosis which involves bones losing an essential ingredient called calcium. The calcium exists in bones as minute crystals which are a bit like the grains of sand in concrete. As more and more of the calcium crystals are lost our bones get weaker and weaker and therefore they become more prone to breaking under the pressures of our daily activities. So falls which earlier in life would cause a bruise and perhaps a sprain may instead cause ribs or hips to snap!
This picture shows a greatly magnified picture of the structure of the "spongy" or cancellous bone which makes up the inner portion of bones. The outer portion of bones or "cortex" is more solid and supports more of the weight than the inner structure.
What Causes Osteoporosis?
There are many different causes for our bones becoming more brittle or chalky as some people say (just like a piece of blackboard chalk can snap unexpectedly in our hands).
Firstly, some people inherit a tendency to have brittle bones. The worst form of this is a congenital disease called osteogenesis imperfecta and children born with this genetic problem will have several fractures even before their first birthday! Now fortunately this is a very rare problem indeed but more minor degrees of weakness are probably more common.
Secondly, poor diet in childhood and early adult life will ensure that young adults' bones don't grow as strong as they should. Poor calcium intake later in life will also allow the bones to get weaker and more fragile. Slender people are also at more risk of developing osteoporosis later in life than overweight people as they have less "bone mass" to begin with!
Thirdly, low levels of physical exercise especially in childhood and early adult life means that muscles don't get strong and therefore the bones don't grow particularly strong. So if the bones are lighter earlier in life, then when calcium starts to leach out of the bones later in life then the bones don't have as much to lose before they are dangerously fragile!
Fourthly, some medicines which are prescribed by doctors can contribute to loss of calcium from bones. The most important contributor to mineral loss is cortisone, particularly in tablet form. Asthmatics who use inhaled forms of cortisone are at much less risk. However if asthmatics need to use large doses of inhaled cortisone every day just to keep their asthma under control they may then be at risk of developing osteoporosis. So cortisone can be a "double-edged sword" both helping to keep people alive but making their bones progressively more fragile.
Fifthly, smoking and excessive alcohol intake can both contribute to more rapid loss of calcium from bones.
Finally, with declining levels of strogen and testosterone in late middle age, women and men respectively start to lose calcium from their bones. These hormones are essential in the maintenance of strong bones and as the blood levels fall with increasing age the protective effect they exert on bones is progressively lost. Women lose up to 10% of their bone mineral content in the first 12 months after menopause. The rate at which they lose calcium from their bones slowly declines but after menopause begins they lose calcium continuously and unfortunately no amount of dietary calcium supplements will stop the loss!
How Does One Know If One Has Osteoporosis?
Usually special tests are needed to demonstrate exactly how much mineral has been lost from ones bones. Ordinary xrays are not very good for measuring remaining bone mineral content with any precision but they will reveal quite advanced osteoporosis. Unfortunately by the time this comes to light several fractures may well have already happened and it's hard to strengthen calcium-depleted bones by this stage. A special test called a DEXA scan can be done - it involves taking several xray images of specific parts of certain bones such as the outer and upper part of the thigh bone, part of the pelvic bone and portions of the lumbar vertebræ (lower part of the spine). This is an expensive test and government subsidy for the test is restricted so that it can't be ordered by doctors for just anybody who requests it. Those patients who don't fit in to the government restrictions but still want the test will have to bear the full price unfortunately. However it is probably the most accurate way of determining exactly how much mineral is in the bones and whether the level is normal for one's age group or substantially lower.
What Are The Bad Problems Caused By Osteoporosis?
Obviously if the bones which support our body weight become broken WE can't support our body weight! People with osteoporosis commonly fracture their hips. This happens even without having a fall and some doctors speculate that the hip fractures commonly occur with a twisting movement which snaps the top end of the thigh bone near the hip joint. The pain caused by the fracture then causes the unlucky victim to fall and it's the fall which is blamed rather than the effect of twisting on a fragile thigh bone! Unfortunately many old people die while in hospital recovering from fractured hips, commonly when they develop pneumonia after spending too long in bed during their convalescence. Also they often require admission to hostels or even nursing homes if they fail to regain their previous mobility and independence. This on it's own causes a major decline in a person's quality of life and their self-esteem, not to mention the enormous cost to the taxpayer or the patient for institutional care!
Many people slowly develop compression or crush fractures of their vertebræ particularly in the thoracic (or chest) part of the spine. When this happens the bones usually don't squash down uniformly and often the front of the vertebra is more crushed than the back of the vertebra and it develops a "wedge" shape. This often happens so insidiously that no-one notices until it is so advanced that a severe forward curvature of the spine has occurred. This causes what is known as the "dowager's hump" or in medical terms as the thoracic kyphosis.
Occasionally a minor fall will cause a sudden and very painful compression fracture of one or more vertebræ and this can cause quite disabling pain which can last for many months. Some people are unlucky enough to suffer several of very these painful fractures one after the other!
What Can Be Done To Prevent Osteoporosis?
Choose your parents well! At least watch to see if your parents develop osteoporosis and if they do, then watch out for your own bones' health!
Keep physically active. It's been shown that doing light workouts with weights can strengthen bones quite substantially. The weights don't have to be enormous and one doesn't have to become an Arnold Schwarznegger (once described as "a condom stuffed with walnuts!") to benefit from workouts. Aerobic activities can also be very helpful. And older people who workout with light weights usually feel healthier and happier as they get stronger and fitter!
Eat a healthy diet with plenty of natural calcium - low fat, calcium-enriched milk is very useful as are small portions of lean meat, fish and legumes.
Stop smoking and control your alcohol intake to recognised safe levels (3-4 standard drinks daily is a safe maximum for men while for women the level is 1-2 standard drinks).
Ask your doctor if any medicines you take are likely to cause osteoporosis and if so, get yourself tested for osteoporosis. Ask if safer alternatives can be taken.
Consider taking hormone replacement therapy once it's obvious that menopause (or "manopause" in men) is starting especially if hot flushes start to happen or if periods either stop happening or become irregular and heavy. Unfortunately the effects of climacteric are usually less obvious in men!
What Can Treatment Do For Established and Advanced Osteoporosis?
Medications for osteoporosis cannot hasten the rate of repair of fracture and they just cannot restore crushed bones to their former uncrushed shape. So people who have painful compression fractures of their spine will NOT lose the pain they endure any faster if they take osteoporosis medications. However taking some of the more modern tablets for osteoporosis CAN stop the loss of calcium from one's bones and some of the newest tablets can even reverse the process so that calcium is actually deposited back into the bones! This can lead to bones becoming a little bit stronger and this can lower the risk of fractures happening in the future.
Taking hormone replacement therapy will not increase the amount of calcium in one's bones but this therapy will stop loss of calcium while is being take. If the hormonal treatment is stopped, calcium again starts to leave the bones!
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