Osteoporosis, which literally means "porous bone", is a disease in which the density and quality of bone are reduced. As the bones become less strong and fragile, the risk of fracture is greatly increased. The loss of bone occurs "silently" and progressively. Often there are no symptoms until the first fracture occurs.

The most common fractures associated with osteoporosis occur at the hip, spine and wrist. The incidence of these fractures, particularly at the hip and spine, increases with age in both women and men.

Notable are vertebral (spinal) and hip fractures. Vertebral fractures can result in serious consequences, including loss of height, intense back pain and deformity. A hip fracture often requires surgery and may result in loss of independent living.

The good news is that osteoporosis is now a largely treatable condition and, with a combination of lifestyle changes and appropriate medical treatment, many fractures can be avoided.

Due to its important prevalence, worldwide osteoporosis is considered as a serious public health concern. Currently it is estimated that over 200 million people worldwide suffer from this disease. Approximately 30% of all postmenopausal women have osteoporosis in the United States and in Europe. At least 40% of these women and 15-30% of men will sustain one or more fragility fractures in their remaining lifetime. Ageing of population will be responsible for a major increase of the incidence of osteoporosis.

It has been shown that an initial fracture is a major risk factor for a new fracture. An increased risk of 86% for any fracture has been demonstrated in people, that have already sustained a fracture. Patients with a history of vertebral fracture have a 2.3-fold increased risk of future hip fracture and a 1.4-fold increase in risk of distal forearm fracture.

Vertebral Fractures

Vertebral fractures are rarely reported by physicians and remain most of the time ignored. Few cases of vertebral fractures result in hospitalisation, however they cause pain and substantial loss of quality of life.
In Europe, the prevalence defined by radiological criteria increases with age in both sexes and is almost as high in men as in women: 12% in females and 12% in males. This fact could be explained by occupation-associated trauma in men.
New fractures are most likely in nearby vertebrae, and they occur more frequently in the mid-thoracic or thoracolumbar regions of the spine.

Hip fractures

Hip fracture is associated with serious disability and excess mortality. Women who have sustained a hip fracture have a 10-20% higher mortality. Hip fracture rates vary markedly between populations.

Distal forearm fractures

Distal forearm fractures are an early and sensitive marker of male skeletal fragility.

Aging men carry a higher absolute risk for hip fractures than spinal fractures in comparison to women.

Bone mineral density (BMD), assessed by dual-energy X-ray absortiometry (DXA) remains the gold standard for the diagnosis of osteoporosis.

BMD can be expressed as:

·                     T-score (the number of standard deviations (SD) above or below the mean BMD values for a young healthy adult)

·                     Z-score (the number deviations above or below the mean BMD values for a population of the same age and gender)

Based on the 1994 WHO report, osteoporosis in women is defined as a BMD value at least -2.5 SD below the mean value of a young healthy population (T-score≤-2.5).

Clinical risk factors can provide information on the risk of fractures in individual patients. BMD assessment is required to confirm the diagnosis since fractures only occur at advanced stages of the disease.

BMD measurement

Dual-energy X-ray Absorptiometry (DXA)

Diagnosis of osteoporosis is generally based on assessment of BMD at the spine and proximal femur by DXA. There is currently some debate about the use of DXA in a mass screening scenario or in more focused case-finding strategies. The decision will be mainly based on economical grounds.
DXA has demonstrated good performance characteristics for diagnosis, assessment of prognosis, monitoring of natural history of the disorder, and assessment of response to some pharmacological treatments.

Quantitative Ultrasound (QUS) provides some information on the structural organisation of bone in addition to bone mass, with no exposure to ionising radiation. Some studies have suggested a similar ability like DXA to discriminate between osteoporotic and non-osteoporotic patients.

It can be used to predict fracture risk, but it cannot be used for the diagnosis of osteoporosis or for monitoring the effects of treatment.

Quantitative Computer Tomography (QCT) measures true volumetric bone mineral content by separately measuring trabecular and cortical bone three-dimensionally. QCT is extensively used in clinical research. However, it remains much more expensive, less accessible and uses higher radiation exposure than DXA.

Radiological assessment of vertebral fracture, a semiquantitative method based on visual inspection has been developed. It has been extensively used in clinical trials and epidemiological studies. The severity of the fracture is assessed by measuring the extent of vertebral height reduction, by its morphological changes, and by differentiating the fracture from nonfracture deformities.

Bone turnover markers (BTM)

BTM have been extensively used in clinical research to monitor the efficacy and mechanisms of action of new drugs. There are three categories of BTM depending on their origination from the bone mineral unit (BMU): bone resorption markers, bone formation markers and markers of osteoclast regulatory protein.

These markers, measured in serum or urine, are not disease-specific. They assess alterations in skeletal metabolism, regardless of the underlying cause.

Assessment of fracture risk

The aim of assessment of fracture risk is to detect individuals at high risk, who deserve the initiation of antiosteoporotic treatment, and conversely to avoid unnecessary treatments in people at low risk.

Risk Factors

BMD assessed by DXA is currently the best predictor of the risk of  future fracture of an individual; it is also, most often, the only diagnostic tool available for clinicians in daily practice. However, several other determinants should be considered when assessing the fracture probability. Skeletal and non-skeletal risk factors may be combined to identify individuals at the highest risk of fracture through case-finding strategies.

Non-skeletal factors

·                     Cigarette smoking  

·                     Excessive alcohol consumption

·                     Low body mass index (BMI)

·                     Low dietary calcium intake

·                     Vitamin D deficiency

·                     Prolonged immobilisation – Little or no physical activity

·                     Visual impairment

·                     Frequent falls

Skeletal factors

·                     Female gender

·                     Premature menopause

·                     Primary or secondary amenorrhoea

·                     Primary and secondary hypogonadism in men

·                     Age

·                     Asian or Caucasian race

·                     Previous fragility fracture  

·                     Family history of hip fracture

·                     Low BMD

·                     High bone turnover

·                     Neuromuscular disorders

·                     Glucocorticoid long-term therapy

·                     Rheumatoid arthritis

Contribution of risk factors in fracture risk assessment

The use of risk factors provides additional information on fracture risk, independently of BMD. An algorithm, combining some of them, together with BMD assessment providing the absolute 10-year fracture risk in an individual will be soon released by a WHO Working Group (supported by IOF). These risks factors are also used to assess fracture risk in countries where DXA machines are not easily available for patients (cost of BMD test, low number of machines…).

Prevention

Although genetic factors play a large part in determining whether an individual is at heightened risk of osteoporosis, lifestyle factors can influence bone development in youth and also the rate of bone loss later in life. Nutrition, exercise and other lifestyle factors have a key role in determining bone health.

Children and adolescents should:

·                     Ensure an adequate calcium intake which meets the relevant dietary recommendations in the country or region where they live

·                     Avoid undernutrition and protein malnutrition

·                     Maintain an adequate supply of vitamin D through sufficient exposure to the sun and through diet

·                     Participate in regular physical activity

·                     Avoid smoking

·                     Be educated about the risk of high alcohol consumption

Adulthood:

Bone mass acquired during youth is an important determinant of the risk of osteoporotic fracture during later life. The higher the peak bone mass, the lower the risk of osteoporosis. Once peak bone mass has been reached, it is maintained by a process called "remodeling” – a continuous process in which old bone is removed (resorption) and new bone is created (formation). The renewal of bone is responsible for bone strength throughout life.

During childhood and the beginning of adulthood, bone formation is more important than bone resorption. In later life, however, the rate of bone resorption is greater than the rate of bone formation and results in net bone loss. Any factor which causes a higher rate of bone remodelling will ultimately lead to a more rapid loss of bone mass and thus more fragile bones. The nutritional and lifestyle criteria for building strong bones in youth is also applicable to adults to prevent excessive bone loss:

·                     Adequate calcium and vitamin D intake (recommendations range from country-to-country, varying between 800 to 1300 mg per day, depending on age)

·                     Regular, weight-bearing exercise

·                     Not smoking

·                     Avoid heavy drinking

·                     Persons of middle age and beyond should follow these fundamental principles. They should also assess their risk of developing osteoporosis and, with medical advice, consider medications to help maintain an optimal bone mass and to decrease the risk of fracture.

Exercise

Exercise plays an important role in building and maintaining bone strength.  Just like muscles, bones respond when they are “stressed,” in other words, when they are forced to bear more weight than they are used to. This can be achieved by “weight bearing” or impact exercises such as walking, running, lifting weights, jumping, or dancing. Low impact or “non-weight bearing” exercises, such as cycling or swimming will not have the same ‘loading’ effect on bones, but are nevertheless excellent for overall health, and improve muscle strength.

A regular, well-structured exercise regimen is a necessary component in osteoporosis prevention. It can also help protect against osteoporosis-related fractures, and aid in rehabilitation. Clearly, all exercise regimens should be appropriate to individual capabilities and, in people with osteoporosis or other medical conditions, should be specially targeted under professional supervision.

Exercise builds bone in children

How long a house will last depends on how strong the foundation is. Likewise, how long bones stay healthy depends on how well they were made to begin with.

Most people reach their “peak bone mass” in their 20s. This is when bones have achieved their maximal density and strength. After peak bone mass is reached, bone density remains stable during adulthood, and then begins to decline. Although nutrition – especially sufficient calcium, vitamin D and protein - are critical for bone development, recent studies have shown that in laying down the bone foundation that will serve for a lifetime, exercise is just as important. This is true throughout childhood and adolescence, but especially important around the growth spurt at puberty (1).

For example, it has been shown that the most physically active young girls gain about 40% more bone mass than the least active girls of the same age (2). This extra bone contributes to peak bone mass, and should give these more active girls an advantage in later life. In girls, the bone tissue accumulated during the ages of 11 to 13 approximately equals the amount lost during the 30 years following menopause (3).

Exercise helps maintain bone in adults and the elderly

In adults exercise plays a key role in preventing bone loss and maintaining muscle strength. Perhaps nowhere is this more obvious than in people who are forced to maintain bed rest. In a study to investigate the effects of long-term space travel, healthy, young volunteers were prevented from using their muscles for extended periods. After spending months lying flat, not doing any exercise, they experienced weak muscles and bone loss. Up to 15% of their bone mineral density was lost in as little as three months (4).  Such studies demonstrate that exercise and bone maintenance are inextricably linked.

Targeted exercise in particular can effect bone strength and reduce the risk of fractures. Studies from the USA and Japan, found that when older, postmenopausal women used small weights to strengthen their back muscles over a period of about two years, ten years down the road, they had stronger back muscles than their peers who did not exercise. Their bones were stronger too, particularly their vertebrae. But what is probably even more important, these back strengthening exercises reduced the chance of getting a fracture by almost three-fold (5). In these women, aged from 58 to 75, only about 11% of those who exercised were found to have at least one vertebral fracture, while just over 30% had suffered a fracture in the group that had not used the exercise regimen.

Women who had not taken part in the back exercise program were also about twice as likely to have a compression fracture in the spine, or have “wedged” vertebrae.

Exercise helps posture and balance

Though a person with osteoporosis has a much greater risk of suffering a bone fracture than someone with normal bone mineral density, it is often a fall that causes the fracture. This puts elderly people at even greater risk of fracturing a bone because they tend to fall more often. In fact, every year about two out of five (40%) people over 65 fall at least once.  So how can falls be prevented? Following treatment for an injurious fall, older people should be offered multidisciplinary assessment to identify and address future risk, and individualized intervention aimed at promoting independence and improving physical and psychological function. In addition to an assessment of home hazards, visual impairment and medication, it is essential that strength and balance training are offered.

Numerous studies have shown that people with better posture, better balance, and greater muscle power are much less likely to fall and are therefore less likely to be injured. On the other hand, those with a more sedentary lifestyle are more likely to have a hip fracture than those who are more active. For example, women who sit for more than nine hours a day are 50% more likely to have a hip fracture than those who sit for less than six hours a day.

Because of these findings, many research groups have been investigating the benefits of exercise in the elderly as a means to improve their coordination, strength and balance.

When data is pooled from these studies it shows that in women over 80 years old, an individually tailored exercise regimen that incorporates progressive muscle strengthening, training for balance, and a walking plan, can reduce the overall risk of falling by about 20%, and cut serious injury-sustaining falls by just over 30%.

The balance aspect of this training may be key. A study has shown, for example, that patients practicing Tai Chi, an ancient Chinese martial art that focuses on balance, fall only half as much as their peers. This significant improvement was achieved after only 15 weeks, during which the patients received one Tai Chi lesson per week with an instructor and were asked to practice twice daily for 15 minutes on their own.

Exercise aids rehabilitation

Exercise can also play a crucial role in rehabilitation. Muscle strengthening exercises can help to rebuild bone in those who have developed osteoporosis, and it can also provide relief from one of the most debilitating symptoms of osteoporosis: pain.

Chronic pain is perhaps most problematic in people with kyphosis, or curvature of the spine most often due to osteoporotic fractures of the vertebrae. Kyphosis causes loss of height, poor posture, and a shift in the center of gravity. Because of these changes, people with kyphosis have a greater risk of falling and possibly having a fracture. In the worst cases, the curvature of the spine is so severe that the rib cage is pressed down against the pelvis. This most often happens when vertebral fractures lead to an additional loss of height. Forced into this posture, patients can suffer chronic, severe pain, and can also have trouble breathing. Exercise can help relieve the pain and some of the symptoms of kyphosis. By strengthening the muscles in the back, the spine can be brought more upright. This has been shown to increase mobility and reduce pain. This type of therapy can greatly improve the quality of life of the patient.

Hip fractures may be the most serious complication that can arise from osteoporosis. More than 95% of patients require surgery to repair their hip fracture, and of these, fewer than one-third will regain normal functioning, and a further one-third have to give up independent living and need constant care. Recent studies have shown that intensive exercise training can lead to improvements in strength and function in elderly patients who have had hip replacement surgery . Patients who received the exercise therapy were significantly better at a variety of daily living fundamentals, such as getting up, walking, climbing stairs and maintaining posture. For example, they walked on average 50% faster and climbed stairs about 30% faster than patients who did not receive the exercise regimen. Emotionally, patients who had received the exercise therapy were less distressed by their overall condition than patients who did not, although both groups of patients were equally as fearful of falling.

Nutrition

Nutrition and Bone Health

The critical years for building bone mass are during childhood and adolescence. This is when new bone is formed more quickly than old bone is removed, causing bones to become larger and denser. This pace continues until around the mid 20’s when ‘peak bone mass’ is normally reached (maximum bone density). Bone tissue loss generally begins after the age of about 40 years, when we are no longer able to replace bone tissue as quickly as we lose it. In women, the rate of bone tissue loss increases quite substantially in the few years immediately after menopause, when estrogen production stops and bones no longer benefit from its protective effect. Men also suffer from loss of bone tissue after age 50 years, but the rate of loss is slower than in women. At this stage in life, taking preventive measures – including ensuring a balanced, healthy diet – will help to slow the rate of bone tissue thinning and reduce the risk of having osteoporosis related fractures, for both men and women.

Good nutrition, especially protein, calcium and vitamin D, is important for preserving bone mass and strength in adults and the elderly. In addition, attention to nutrition is an important component of a successful rehabilitation program in patients who have had an osteoporotic fracture. The importance of this lifestyle factor is that it is amenable to change: individuals can take positive steps to strengthen their bones and reduce their risk of osteoporosis.

Osteoporosis, which literally means "porous bone", is a disease in which the density and quality of bone are reduced. As the bones become less strong and fragile, the risk of fracture is greatly increased. The loss of bone occurs "silently" and progressively. Often there are no symptoms until the first fracture occurs.

The most common fractures associated with osteoporosis occur at the hip, spine and wrist. The incidence of these fractures, particularly at the hip and spine, increases with age in both women and men.

Notable are vertebral (spinal) and hip fractures. Vertebral fractures can result in serious consequences, including loss of height, intense back pain and deformity. A hip fracture often requires surgery and may result in loss of independent living.

The good news is that osteoporosis is now a largely treatable condition and, with a combination of lifestyle changes and appropriate medical treatment, many fractures can be avoided.

Due to its important prevalence, worldwide osteoporosis is considered as a serious public health concern. Currently it is estimated that over 200 million people worldwide suffer from this disease. Approximately 30% of all postmenopausal women have osteoporosis in the United States and in Europe. At least 40% of these women and 15-30% of men will sustain one or more fragility fractures in their remaining lifetime. Ageing of population will be responsible for a major increase of the incidence of osteoporosis.

It has been shown that an initial fracture is a major risk factor for a new fracture. An increased risk of 86% for any fracture has been demonstrated in people, that have already sustained a fracture. Patients with a history of vertebral fracture have a 2.3-fold increased risk of future hip fracture and a 1.4-fold increase in risk of distal forearm fracture.

Vertebral Fractures

Vertebral fractures are rarely reported by physicians and remain most of the time ignored. Few cases of vertebral fractures result in hospitalisation, however they cause pain and substantial loss of quality of life.
In Europe, the prevalence defined by radiological criteria increases with age in both sexes and is almost as high in men as in women: 12% in females and 12% in males. This fact could be explained by occupation-associated trauma in men.
New fractures are most likely in nearby vertebrae, and they occur more frequently in the mid-thoracic or thoracolumbar regions of the spine.

Hip fractures

Hip fracture is associated with serious disability and excess mortality. Women who have sustained a hip fracture have a 10-20% higher mortality. Hip fracture rates vary markedly between populations.

Distal forearm fractures

Distal forearm fractures are an early and sensitive marker of male skeletal fragility.

Aging men carry a higher absolute risk for hip fractures than spinal fractures in comparison to women.

Bone mineral density (BMD), assessed by dual-energy X-ray absortiometry (DXA) remains the gold standard for the diagnosis of osteoporosis.

BMD can be expressed as:

·                     T-score (the number of standard deviations (SD) above or below the mean BMD values for a young healthy adult)

·                     Z-score (the number deviations above or below the mean BMD values for a population of the same age and gender)

Based on the 1994 WHO report, osteoporosis in women is defined as a BMD value at least -2.5 SD below the mean value of a young healthy population (T-score≤-2.5).

Clinical risk factors can provide information on the risk of fractures in individual patients. BMD assessment is required to confirm the diagnosis since fractures only occur at advanced stages of the disease.

BMD measurement

Dual-energy X-ray Absorptiometry (DXA)

Diagnosis of osteoporosis is generally based on assessment of BMD at the spine and proximal femur by DXA. There is currently some debate about the use of DXA in a mass screening scenario or in more focused case-finding strategies. The decision will be mainly based on economical grounds.
DXA has demonstrated good performance characteristics for diagnosis, assessment of prognosis, monitoring of natural history of the disorder, and assessment of response to some pharmacological treatments.

Quantitative Ultrasound (QUS) provides some information on the structural organisation of bone in addition to bone mass, with no exposure to ionising radiation. Some studies have suggested a similar ability like DXA to discriminate between osteoporotic and non-osteoporotic patients.

It can be used to predict fracture risk, but it cannot be used for the diagnosis of osteoporosis or for monitoring the effects of treatment.

Quantitative Computer Tomography (QCT) measures true volumetric bone mineral content by separately measuring trabecular and cortical bone three-dimensionally. QCT is extensively used in clinical research. However, it remains much more expensive, less accessible and uses higher radiation exposure than DXA.

Radiological assessment of vertebral fracture, a semiquantitative method based on visual inspection has been developed. It has been extensively used in clinical trials and epidemiological studies. The severity of the fracture is assessed by measuring the extent of vertebral height reduction, by its morphological changes, and by differentiating the fracture from nonfracture deformities.

Bone turnover markers (BTM)

BTM have been extensively used in clinical research to monitor the efficacy and mechanisms of action of new drugs. There are three categories of BTM depending on their origination from the bone mineral unit (BMU): bone resorption markers, bone formation markers and markers of osteoclast regulatory protein.

These markers, measured in serum or urine, are not disease-specific. They assess alterations in skeletal metabolism, regardless of the underlying cause.

Assessment of fracture risk

The aim of assessment of fracture risk is to detect individuals at high risk, who deserve the initiation of antiosteoporotic treatment, and conversely to avoid unnecessary treatments in people at low risk.

Risk Factors

BMD assessed by DXA is currently the best predictor of the risk of  future fracture of an individual; it is also, most often, the only diagnostic tool available for clinicians in daily practice. However, several other determinants should be considered when assessing the fracture probability. Skeletal and non-skeletal risk factors may be combined to identify individuals at the highest risk of fracture through case-finding strategies.

Non-skeletal factors

·                     Cigarette smoking  

·                     Excessive alcohol consumption

·                     Low body mass index (BMI)

·                     Low dietary calcium intake

·                     Vitamin D deficiency

·                     Prolonged immobilisation – Little or no physical activity

·                     Visual impairment

·                     Frequent falls

Skeletal factors

·                     Female gender

·                     Premature menopause

·                     Primary or secondary amenorrhoea

·                     Primary and secondary hypogonadism in men

·                     Age

·                     Asian or Caucasian race

·                     Previous fragility fracture  

·                     Family history of hip fracture

·                     Low BMD

·                     High bone turnover

·                     Neuromuscular disorders

·                     Glucocorticoid long-term therapy

·                     Rheumatoid arthritis

Contribution of risk factors in fracture risk assessment

The use of risk factors provides additional information on fracture risk, independently of BMD. An algorithm, combining some of them, together with BMD assessment providing the absolute 10-year fracture risk in an individual will be soon released by a WHO Working Group (supported by IOF). These risks factors are also used to assess fracture risk in countries where DXA machines are not easily available for patients (cost of BMD test, low number of machines…).

Prevention

Although genetic factors play a large part in determining whether an individual is at heightened risk of osteoporosis, lifestyle factors can influence bone development in youth and also the rate of bone loss later in life. Nutrition, exercise and other lifestyle factors have a key role in determining bone health.

Children and adolescents should:

·                     Ensure an adequate calcium intake which meets the relevant dietary recommendations in the country or region where they live

·                     Avoid undernutrition and protein malnutrition

·                     Maintain an adequate supply of vitamin D through sufficient exposure to the sun and through diet

·                     Participate in regular physical activity

·                     Avoid smoking

·                     Be educated about the risk of high alcohol consumption

Adulthood:

Bone mass acquired during youth is an important determinant of the risk of osteoporotic fracture during later life. The higher the peak bone mass, the lower the risk of osteoporosis. Once peak bone mass has been reached, it is maintained by a process called "remodeling” – a continuous process in which old bone is removed (resorption) and new bone is created (formation). The renewal of bone is responsible for bone strength throughout life.

During childhood and the beginning of adulthood, bone formation is more important than bone resorption. In later life, however, the rate of bone resorption is greater than the rate of bone formation and results in net bone loss. Any factor which causes a higher rate of bone remodelling will ultimately lead to a more rapid loss of bone mass and thus more fragile bones. The nutritional and lifestyle criteria for building strong bones in youth is also applicable to adults to prevent excessive bone loss:

·                     Adequate calcium and vitamin D intake (recommendations range from country-to-country, varying between 800 to 1300 mg per day, depending on age)

·                     Regular, weight-bearing exercise

·                     Not smoking

·                     Avoid heavy drinking

·                     Persons of middle age and beyond should follow these fundamental principles. They should also assess their risk of developing osteoporosis and, with medical advice, consider medications to help maintain an optimal bone mass and to decrease the risk of fracture.

Exercise

Exercise plays an important role in building and maintaining bone strength.  Just like muscles, bones respond when they are “stressed,” in other words, when they are forced to bear more weight than they are used to. This can be achieved by “weight bearing” or impact exercises such as walking, running, lifting weights, jumping, or dancing. Low impact or “non-weight bearing” exercises, such as cycling or swimming will not have the same ‘loading’ effect on bones, but are nevertheless excellent for overall health, and improve muscle strength.

A regular, well-structured exercise regimen is a necessary component in osteoporosis prevention. It can also help protect against osteoporosis-related fractures, and aid in rehabilitation. Clearly, all exercise regimens should be appropriate to individual capabilities and, in people with osteoporosis or other medical conditions, should be specially targeted under professional supervision.

Exercise builds bone in children

How long a house will last depends on how strong the foundation is. Likewise, how long bones stay healthy depends on how well they were made to begin with.

Most people reach their “peak bone mass” in their 20s. This is when bones have achieved their maximal density and strength. After peak bone mass is reached, bone density remains stable during adulthood, and then begins to decline. Although nutrition – especially sufficient calcium, vitamin D and protein - are critical for bone development, recent studies have shown that in laying down the bone foundation that will serve for a lifetime, exercise is just as important. This is true throughout childhood and adolescence, but especially important around the growth spurt at puberty (1).

For example, it has been shown that the most physically active young girls gain about 40% more bone mass than the least active girls of the same age (2). This extra bone contributes to peak bone mass, and should give these more active girls an advantage in later life. In girls, the bone tissue accumulated during the ages of 11 to 13 approximately equals the amount lost during the 30 years following menopause (3).

Exercise helps maintain bone in adults and the elderly

In adults exercise plays a key role in preventing bone loss and maintaining muscle strength. Perhaps nowhere is this more obvious than in people who are forced to maintain bed rest. In a study to investigate the effects of long-term space travel, healthy, young volunteers were prevented from using their muscles for extended periods. After spending months lying flat, not doing any exercise, they experienced weak muscles and bone loss. Up to 15% of their bone mineral density was lost in as little as three months (4).  Such studies demonstrate that exercise and bone maintenance are inextricably linked.

Targeted exercise in particular can effect bone strength and reduce the risk of fractures. Studies from the USA and Japan, found that when older, postmenopausal women used small weights to strengthen their back muscles over a period of about two years, ten years down the road, they had stronger back muscles than their peers who did not exercise. Their bones were stronger too, particularly their vertebrae. But what is probably even more important, these back strengthening exercises reduced the chance of getting a fracture by almost three-fold (5). In these women, aged from 58 to 75, only about 11% of those who exercised were found to have at least one vertebral fracture, while just over 30% had suffered a fracture in the group that had not used the exercise regimen.

Women who had not taken part in the back exercise program were also about twice as likely to have a compression fracture in the spine, or have “wedged” vertebrae.

Exercise helps posture and balance

Though a person with osteoporosis has a much greater risk of suffering a bone fracture than someone with normal bone mineral density, it is often a fall that causes the fracture. This puts elderly people at even greater risk of fracturing a bone because they tend to fall more often. In fact, every year about two out of five (40%) people over 65 fall at least once.  So how can falls be prevented? Following treatment for an injurious fall, older people should be offered multidisciplinary assessment to identify and address future risk, and individualized intervention aimed at promoting independence and improving physical and psychological function. In addition to an assessment of home hazards, visual impairment and medication, it is essential that strength and balance training are offered.

Numerous studies have shown that people with better posture, better balance, and greater muscle power are much less likely to fall and are therefore less likely to be injured. On the other hand, those with a more sedentary lifestyle are more likely to have a hip fracture than those who are more active. For example, women who sit for more than nine hours a day are 50% more likely to have a hip fracture than those who sit for less than six hours a day.

Because of these findings, many research groups have been investigating the benefits of exercise in the elderly as a means to improve their coordination, strength and balance.

When data is pooled from these studies it shows that in women over 80 years old, an individually tailored exercise regimen that incorporates progressive muscle strengthening, training for balance, and a walking plan, can reduce the overall risk of falling by about 20%, and cut serious injury-sustaining falls by just over 30%.

The balance aspect of this training may be key. A study has shown, for example, that patients practicing Tai Chi, an ancient Chinese martial art that focuses on balance, fall only half as much as their peers. This significant improvement was achieved after only 15 weeks, during which the patients received one Tai Chi lesson per week with an instructor and were asked to practice twice daily for 15 minutes on their own.

Exercise aids rehabilitation

Exercise can also play a crucial role in rehabilitation. Muscle strengthening exercises can help to rebuild bone in those who have developed osteoporosis, and it can also provide relief from one of the most debilitating symptoms of osteoporosis: pain.

Chronic pain is perhaps most problematic in people with kyphosis, or curvature of the spine most often due to osteoporotic fractures of the vertebrae. Kyphosis causes loss of height, poor posture, and a shift in the center of gravity. Because of these changes, people with kyphosis have a greater risk of falling and possibly having a fracture. In the worst cases, the curvature of the spine is so severe that the rib cage is pressed down against the pelvis. This most often happens when vertebral fractures lead to an additional loss of height. Forced into this posture, patients can suffer chronic, severe pain, and can also have trouble breathing. Exercise can help relieve the pain and some of the symptoms of kyphosis. By strengthening the muscles in the back, the spine can be brought more upright. This has been shown to increase mobility and reduce pain. This type of therapy can greatly improve the quality of life of the patient.

Hip fractures may be the most serious complication that can arise from osteoporosis. More than 95% of patients require surgery to repair their hip fracture, and of these, fewer than one-third will regain normal functioning, and a further one-third have to give up independent living and need constant care. Recent studies have shown that intensive exercise training can lead to improvements in strength and function in elderly patients who have had hip replacement surgery . Patients who received the exercise therapy were significantly better at a variety of daily living fundamentals, such as getting up, walking, climbing stairs and maintaining posture. For example, they walked on average 50% faster and climbed stairs about 30% faster than patients who did not receive the exercise regimen. Emotionally, patients who had received the exercise therapy were less distressed by their overall condition than patients who did not, although both groups of patients were equally as fearful of falling.

Nutrition

Nutrition and Bone Health

The critical years for building bone mass are during childhood and adolescence. This is when new bone is formed more quickly than old bone is removed, causing bones to become larger and denser. This pace continues until around the mid 20’s when ‘peak bone mass’ is normally reached (maximum bone density). Bone tissue loss generally begins after the age of about 40 years, when we are no longer able to replace bone tissue as quickly as we lose it. In women, the rate of bone tissue loss increases quite substantially in the few years immediately after menopause, when estrogen production stops and bones no longer benefit from its protective effect. Men also suffer from loss of bone tissue after age 50 years, but the rate of loss is slower than in women. At this stage in life, taking preventive measures – including ensuring a balanced, healthy diet – will help to slow the rate of bone tissue thinning and reduce the risk of having osteoporosis related fractures, for both men and women.

Good nutrition, especially protein, calcium and vitamin D, is important for preserving bone mass and strength in adults and the elderly. In addition, attention to nutrition is an important component of a successful rehabilitation program in patients who have had an osteoporotic fracture. The importance of this lifestyle factor is that it is amenable to change: individuals can take positive steps to strengthen their bones and reduce their risk of osteoporosis.