![\"11.7.1](\"https:\/\/pressbooks.ccconline.org\/acchumanbio\/wp-content\/uploads\/sites\/152\/2019\/06\/Blausen_0686_Osteoporosis_01-2.png\")
Figure 11.7.1 Poor posture, or bone degeneration?<\/em>[\/caption]\r\n\r\nDowager\u2019s Hump<\/h1>\r\n<\/div>\r\nThe woman on the right in Figure 11.7.1 has a deformity in her back commonly called dowager\u2019s (widow\u2019s) hump, because it occurs most often in elderly women. Its medical name is kyphosis<\/a>, and it is defined as excessive curvature of the spinal column in the thoracic region. The curvature generally results from fractures of thoracic vertebrae. As the inset drawings suggest, these fractures may occur due to a significant decrease in bone mass, which is called osteoporosis. Osteoporosis is one of the most prevalent\u00a0disorders of the skeletal system.\r\n\r\nCommon\u00a0Skeletal System\u00a0Disorders<\/h1>\r\n<\/div>\r\nA number of disorders affect the skeletal system, including bone fractures and bone cancers. However, the two most common disorders of the skeletal system are [pb_glossary id=\"4122\"]osteoporosis[\/pb_glossary] and [pb_glossary id=\"4102\"]osteoarthritis[\/pb_glossary]. At least ten million people in the United States have osteoporosis, and more than eight million of them are women. Osteoarthritis is even more common, affecting almost 1.4 million people in Canada, and 1 in 4 women over the age of 50. Because osteoporosis and osteoarthritis are so common, they are the focus of this section. These two disorders are also good examples to illustrate the structure and function of the skeletal system.\r\n\r\nOsteoporosis<\/h1>\r\n<\/div>\r\n[pb_glossary id=\"4122\"]Osteoporosis[\/pb_glossary]<\/strong> is an age-related disorder in which bones lose mass, weaken, and break more easily than normal bones. Bones may weaken so much that a fracture can occur with minor stress \u2014 or even spontaneously, without any stress at all. Osteoporosis is the most common cause of broken bones in the elderly, but until a bone fracture occurs, it typically causes no symptoms. The bones that break most often include those in the wrist, hip, shoulder, and spine. When the thoracic vertebrae are affected, there can be a gradual collapse of the vertebrae due to compression fractures, as shown in Figure 11.7.2. This is what causes kyphosis, as pictured above in Figure 11.7.1.\r\n\r\n[caption id=\"attachment_4123\" align=\"aligncenter\" width=\"400\"]![\"11.7](\"https:\/\/pressbooks.ccconline.org\/acchumanbio\/wp-content\/uploads\/sites\/152\/2023\/10\/Feature_Osteoprosis_of_Spine-2.jpg\")
Figure 11.7.2 Compression fractures of thoracic vertebrae are relatively common in people with osteoporosis.<\/em>[\/caption]\r\nChanges in Bone Mass with Age<\/h2>\r\nAs shown in the Figure 11.7.3, bone mass in both males and females generally peaks when people are in their thirties, with males typically attaining a higher peak mass than females. In both sexes, bone mass usually decreases after that, and this tends to occur more rapidly in females, especially after menopause. The greater decrease in females is generally attributable to low levels of estrogen in the post-menopausal years.\r\n\r\n[caption id=\"attachment_4124\" align=\"aligncenter\" width=\"860\"]![\"11.7.3](\"https:\/\/pressbooks.ccconline.org\/acchumanbio\/wp-content\/uploads\/sites\/152\/2023\/10\/Age_and_Bone_Mass-2.jpg\")
Figure 11.7.3 Bone mass is a measure of the total mass of calcium in the bones of the skeleton. As bone mass decreases, the risk of fractures increases.<\/em>[\/caption]\r\nWhat Causes Osteoporosis?<\/h2>\r\nThe underlying mechanism in all cases of osteoporosis is an imbalance between bone formation by [pb_glossary id=\"4040\"]osteoblasts[\/pb_glossary] and bone resorption by [pb_glossary id=\"4042\"]osteoclasts[\/pb_glossary]. Normally, bones are constantly being remodeled by these two processes, with up to ten per cent of all bone mass undergoing remodeling at any point in time. As long as these two processes are in balance, no net loss<\/em> of bone occurs. There are three main ways that an imbalance between bone formation and bone resorption can occur and lead to a net loss of bone. All three ways may occur in the same individual. The three ways are described below:\r\n\r\n \t- \u00a0An individual never develops normal peak bone mass during the young adult years:<\/strong>\u00a0If the peak level is lower than normal, then there is less bone mass to begin with, making osteoporosis more likely to develop.<\/li>\r\n \t
- There is greater than normal bone resorption:<\/strong>\u00a0Bone resorption normally increases after peak bone mass is reached, but age-related bone resorption may be greater than normal for a variety of reasons. One possible reason is calcium or vitamin D deficiency, which causes the parathyroid gland to release PTH, the\u00a0hormone\u00a0that promotes resorption by osteoclasts.<\/li>\r\n \t
- There is inadequate formation of new bone by osteoblasts during remodeling:<\/strong>\u00a0Lack of estrogen may decrease the normal\u00a0deposition\u00a0of new bone. Inadequate levels of calcium and vitamin D also lead to impaired bone formation by osteoblasts.<\/li>\r\n<\/ol>\r\nAn imbalance between bone building and bone destruction leading to bone loss may also occur as a side effect of other disorders. For example, people with alcoholism, anorexia nervosa, or hyperthyroidism have an increased rate of bone loss. Some medications \u2014\u00a0including anti-seizure medications, chemotherapy drugs, steroid medications, and some antidepressants \u2014\u00a0also increase the rate of bone loss.\r\n
Diagnosing Osteoporosis<\/h2>\r\nOsteoporosis is diagnosed by measuring a patient\u2019s bone density and comparing it with the normal level of peak bone density in a young adult reference population of the same sex as the patient. If the patient\u2019s bone density is too far below the normal peak level (as measured by a statistic called a T-score), then osteoporosis is diagnosed. Bone density is usually measured by a type of X-ray called dual-energy X-ray absorptiometry (or DEXA), an example of which is shown in Figure 11.7.4. Typically, the density is measured at the hip. Sometimes, other areas are also measured, because there may be variation in bone density in different parts of the skeleton. Osteoporosis Canada\u00a0 recommends that all women 65 years of age and older be screened with DEXA for bone density. Screening may be recommended at younger ages in people with risk factors for osteoporosis (see Risk Factors for Osteoporosis below).\r\n\r\n[caption id=\"attachment_4126\" align=\"aligncenter\" width=\"530\"]![\"11.7.4](\"https:\/\/pressbooks.ccconline.org\/acchumanbio\/wp-content\/uploads\/sites\/152\/2023\/10\/DEXA_scan_screen_ALSPAC-2.jpg\")
Figure 11.7.4 Dual-energy X-ray absorptiometry is a means of measuring bone mineral density using spectral imaging. Two X-ray beams, with different energy levels, are aimed at the patient's bones. When soft tissue absorption is subtracted out, the bone mineral density can be determined from the absorption of each beam by bone.<\/em>[\/caption]\r\nOsteoporotic Fractures<\/h2>\r\nFractures are the most dangerous aspect of osteoporosis, and osteoporosis is responsible for millions of fractures annually. Debilitating pain among the elderly is often caused by fractures from osteoporosis, and it can lead to further disability and early mortality. Fractures of the long\u00a0bones\u00a0(such as the femur) can impair mobility and may require surgery. Hip fracture usually requires immediate surgery, as well. The immobility associated with fractures \u2014 especially of the hip \u2014 increases the risk of deep vein thrombosis, pulmonary embolism, and pneumonia. Osteoporosis is rarely fatal, but these complications of fractures often are. Older people tend to have more falls than younger people, due to such factors as poor eyesight and balance problems, increasing their risk of fractures even more. The likelihood of falls can be reduced by removing obstacles and loose carpets or rugs in the living environment.\r\nRisk Factors for Osteoporosis<\/h2>\r\nThere are a number of factors that increase the risk of osteoporosis. Eleven of them are listed below. The first five factors cannot be controlled, but the remaining factors generally can be controlled by changing behaviors.\r\n\r\n \t- Older age<\/li>\r\n \t
- Female sex<\/li>\r\n \t
- European or Asian ancestry<\/li>\r\n \t
- Family history of osteoporosis<\/li>\r\n \t
- Short stature and small bones<\/li>\r\n \t
- Smoking<\/li>\r\n \t
- Alcohol consumption<\/li>\r\n \t
- Lack of exercise<\/li>\r\n \t
- Vitamin D deficiency<\/li>\r\n \t
- Poor nutrition<\/li>\r\n \t
- Consumption of soft drinks<\/li>\r\n<\/ol>\r\n
Treatment and Prevention of Osteoporosis<\/h2>\r\nOsteoporosis is often treated with medications that may slow or even reverse bone loss. Medications called bisphosphonates, for example, are commonly prescribed.\u00a0Bisphosphonates slow down the breakdown of bone,\u00a0allowing\u00a0bone rebuilding during remodeling\u00a0to\u00a0keep pace. This helps maintain bone density and decreases the risk of fractures.\u00a0The medications may be more effective in patients who have already broken bones than in those who have not, significantly reducing their risk of another fracture. Generally, patients are not recommended to stay on bisphosphonates for more than three or four years. There is no evidence for continued benefit after this time \u2014 in fact, there is a potential for adverse side effects.\r\n\r\n[caption id=\"attachment_4128\" align=\"alignright\" width=\"491\"]![\"11.7.5](\"https:\/\/pressbooks.ccconline.org\/acchumanbio\/wp-content\/uploads\/sites\/152\/2023\/10\/Hiking-by-jake-melara-Yh6K2eTr_FY-unsplash-scaled-3.jpg\")
Figure 11.7.5 Hiking is an enjoyable way to help keep bones strong and reduce the risk of osteoporosis.<\/em>[\/caption]\r\n\r\nPreventing osteoporosis includes eliminating any risk factors that can be controlled through changes of behavior. If you smoke, stop. If you drink, reduce your alcohol consumption \u2014 or cut it out altogether. Eat a nutritious diet and make sure you are getting adequate amounts of vitamin D. You should also avoid drinking carbonated beverages.\r\n\r\n \r\n\r\nIf you\u2019re a couch potato, get involved in regular exercise. Aerobic, weight-bearing, and resistance exercises can all help maintain or increase bone mineral density (for example hiking as in Figure 11.7.5). Exercise puts stress on bones, which stimulates bone building. Good weight-bearing exercises for bone building include weight training, dancing, stair climbing, running, and hiking (see Figure 11.7.5). Biking and swimming are less beneficial, because they don\u2019t stress the bones. Ideally, you should exercise for at least 30 minutes a day most days of the week.\r\n\r\n \r\nOsteoarthritis<\/span><\/div>\r\n \r\n\r\n[caption id=\"attachment_4129\" align=\"alignleft\" width=\"161\"]![\"11.7.6](\"https:\/\/pressbooks.ccconline.org\/acchumanbio\/wp-content\/uploads\/sites\/152\/2023\/10\/Areas_affected_by_osteoarthritis-2.gif\")
Figure 11.7.6 The areas shaded in blue indicate the joints most commonly affected by OA.<\/em>[\/caption]\r\n\r\n[pb_glossary id=\"4102\"]Osteoarthritis[\/pb_glossary] (OA<\/a>)<\/strong> is a joint disease that results from the breakdown of joint cartilage and bone. The most common symptoms are joint pain and stiffness. Other symptoms may include joint swelling and decreased range of motion. Initially, symptoms may occur only after exercise or prolonged activity, but over time, they may become constant, negatively affecting work and normal daily activities. As shown in Figure 11.7.6, the most commonly involved joints are those near the ends of the fingers, at the bases of the thumbs, and in the neck, lower back, hips, and knees. Often, joints on one side of the body are affected more than those on the other side.\r\n\r\n \r\nWhat Causes Osteoarthritis?<\/h2>\r\nOA is thought to be caused by mechanical stress on the\u00a0joints\u00a0with insufficient self-repair of cartilage. The stress may be exacerbated by low-grade inflammation of the joints, as\u00a0cells\u00a0lining the joint attempt to remove breakdown products from cartilage in the synovial space. OA develops over decades as stress and inflammation cause increasing loss of articular cartilage. Eventually, bones may have no cartilage to separate them, so bones rub against one another at joints. This damages the articular surfaces of the bones and contributes to the pain and other symptoms of OA. Because of the pain, movement may be curtailed, leading to loss of muscle, as well.\r\nDiagnosing Osteoarthritis<\/h2>\r\n[caption id=\"attachment_4131\" align=\"alignright\" width=\"300\"]![\"11.7.7](\"https:\/\/pressbooks.ccconline.org\/acchumanbio\/wp-content\/uploads\/sites\/152\/2023\/10\/Hallux_valgus-2.jpg\")
Figure 11.7.7 A bunion is a common sign of osteoarthritis. It is typically located at the base of the big toe.<\/em>[\/caption]\r\n\r\nDiagnosis of OA is typically made on the basis of signs and symptoms. Signs include joint deformities, such as bony nodules on the finger joints or bunions on the feet (as illustrated in Figure 11.7.7). Symptoms include joint pain and stiffness. The pain is usually described as a sharp ache or burning sensation, which may be in the muscles and tendons around the affected joints, as well as in the joints themselves. The pain is usually made worse by prolonged activity, and it typically improves with rest. Stiffness is most common when first arising in the morning, and it usually improves quickly as daily activities are undertaken.\r\n\r\nX-rays\u00a0or other tests are sometimes used to either support the diagnosis of OA or to rule out other disorders.\u00a0Blood tests might be done, for example, to look for factors that indicate rheumatoid arthritis (RA), an\u00a0autoimmune disease\u00a0in which the immune system attacks the body\u2019s joints. If these factors are not present in the\u00a0blood, then RA is unlikely, and a diagnosis of OA is more likely to be correct.\r\nRisk Factors for Osteoarthritis<\/h2>\r\nAge is the chief risk factor for osteoarthritis. By age 65, as many as 80 per cent of all people have evidence of osteoarthritis. However, people are more likely to develop OA \u2014 especially at younger ages \u2014 if they have had a joint injury. A high school football player might have a bad knee injury that damages the joint, leading to OA in the knee by the time he is in his thirties. If people have joints that are misaligned due to congenital malformations or disease, they are also more likely to develop OA. Excess body weight is another factor that increases the risk of OA, because of the added stress it places on weight-bearing joints.\r\n\r\nResearchers have found that people with a family history of OA have a heightened risk of developing the disorder, which suggests that genetic factors are also involved in OA. It is likely that many different genes are needed for normal cartilage and cartilage repair. If such genes are defective and cartilage is abnormal or not normally repaired, OA is more likely to result.\r\nTreatment and Prevention of Osteoarthritis<\/h2>\r\nOA cannot be cured, but the symptoms \u2014 especially the pain \u2014 can often be treated successfully to maintain good quality of life for people with OA. Treatments include exercise, efforts to decrease stress on joints, pain medications, and surgery.\r\nExercise<\/h3>\r\nExercise helps maintain joint mobility and also increases muscle strength. Stronger muscles may help keep the bones in joints correctly aligned, and this can reduce joint stress. Good exercises for OA include swimming, water aerobics (see Figure 11.7.8 below), and biking. These activities are recommended for OA, because they put relatively little stress on the joints.\r\n\r\n[caption id=\"attachment_4133\" align=\"aligncenter\" width=\"1000\"]![\"11.7.8](\"https:\/\/pressbooks.ccconline.org\/acchumanbio\/wp-content\/uploads\/sites\/152\/2023\/10\/07-06_WtrAerob1a-2.jpg\")
Figure 11.7.8 Exercising in water provides buoyancy that places less stress on joints than the same exercises would on the ground or other hard surface.<\/em>[\/caption]\r\n\r\n\r\n\r\nExercising in water provides buoyancy that places less stress on joints than the same exercises would on the ground or other hard surface.\r\n\r\n<\/div>\r\nDe-stressing Joints<\/h3>\r\nEfforts to decrease stress on joints include resting and using mobility devices such as canes, which reduce the\u00a0weight\u00a0placed on weight-bearing joints and also improve stability. In people who are overweight, losing weight may also reduce joint stress.\r\nPain Medications<\/h3>\r\nThe first type of pain medication likely to be prescribed for OA is acetaminophen (e.g., Tylenol). When taken as prescribed, it has a relatively low risk of serious side effects. If this medication is inadequate to relieve the pain, non-steroidal anti-inflammatory drugs (NSAIDs, such as ibuprofen) may be prescribed. NSAIDs, however, are more likely to cause serious side effects, such as gastrointestinal bleeding, elevated\u00a0blood pressure, and increased risk of stroke. Opioids usually are reserved for patients who have suffered serious side effects or for whom other medications have failed to relieve pain. Due to the risk of [pb_glossary id=\"3184\"]addiction[\/pb_glossary], only short-term use of opioids is generally recommended.\r\nSurgery<\/h3>\r\nJoint-replacement surgery is the most common treatment for serious OA in the knee or hip. In fact, knee and hip replacement surgeries are among the most common of all surgeries. Although they require a long period of healing and physical rehabilitation, the results are usually worth it. The replacement \u201cparts\u201d are usually pain-free and fully functional for at least a couple of decades. Quality, durability, and customization of artificial joints are constantly improving.\r\n\r\nTry out this neat Virtual Hip Resurfacing<\/a> activity by Edheads (you will need to enable Flash).\r\n\r\nFeature: Myth vs. Reality<\/span>\r\n\r\nAbout one out of every 5 adults in Canada suffer from\u00a0 osteoarthritis. The more you know about this disease, the more you can do to avoid it or slow its progression. That means knowing the facts, rather than believing the myths about osteoarthritis.\r\n
Common\u00a0Skeletal System\u00a0Disorders<\/h1>\r\n<\/div>\r\nA number of disorders affect the skeletal system, including bone fractures and bone cancers. However, the two most common disorders of the skeletal system are [pb_glossary id=\"4122\"]osteoporosis[\/pb_glossary] and [pb_glossary id=\"4102\"]osteoarthritis[\/pb_glossary]. At least ten million people in the United States have osteoporosis, and more than eight million of them are women. Osteoarthritis is even more common, affecting almost 1.4 million people in Canada, and 1 in 4 women over the age of 50. Because osteoporosis and osteoarthritis are so common, they are the focus of this section. These two disorders are also good examples to illustrate the structure and function of the skeletal system.\r\n\r\nOsteoporosis<\/h1>\r\n<\/div>\r\n[pb_glossary id=\"4122\"]Osteoporosis[\/pb_glossary]<\/strong> is an age-related disorder in which bones lose mass, weaken, and break more easily than normal bones. Bones may weaken so much that a fracture can occur with minor stress \u2014 or even spontaneously, without any stress at all. Osteoporosis is the most common cause of broken bones in the elderly, but until a bone fracture occurs, it typically causes no symptoms. The bones that break most often include those in the wrist, hip, shoulder, and spine. When the thoracic vertebrae are affected, there can be a gradual collapse of the vertebrae due to compression fractures, as shown in Figure 11.7.2. This is what causes kyphosis, as pictured above in Figure 11.7.1.\r\n\r\n[caption id=\"attachment_4123\" align=\"aligncenter\" width=\"400\"] Figure 11.7.2 Compression fractures of thoracic vertebrae are relatively common in people with osteoporosis.<\/em>[\/caption]\r\nChanges in Bone Mass with Age<\/h2>\r\nAs shown in the Figure 11.7.3, bone mass in both males and females generally peaks when people are in their thirties, with males typically attaining a higher peak mass than females. In both sexes, bone mass usually decreases after that, and this tends to occur more rapidly in females, especially after menopause. The greater decrease in females is generally attributable to low levels of estrogen in the post-menopausal years.\r\n\r\n[caption id=\"attachment_4124\" align=\"aligncenter\" width=\"860\"] Figure 11.7.3 Bone mass is a measure of the total mass of calcium in the bones of the skeleton. As bone mass decreases, the risk of fractures increases.<\/em>[\/caption]\r\nWhat Causes Osteoporosis?<\/h2>\r\nThe underlying mechanism in all cases of osteoporosis is an imbalance between bone formation by [pb_glossary id=\"4040\"]osteoblasts[\/pb_glossary] and bone resorption by [pb_glossary id=\"4042\"]osteoclasts[\/pb_glossary]. Normally, bones are constantly being remodeled by these two processes, with up to ten per cent of all bone mass undergoing remodeling at any point in time. As long as these two processes are in balance, no net loss<\/em> of bone occurs. There are three main ways that an imbalance between bone formation and bone resorption can occur and lead to a net loss of bone. All three ways may occur in the same individual. The three ways are described below:\r\n\r\n \t- \u00a0An individual never develops normal peak bone mass during the young adult years:<\/strong>\u00a0If the peak level is lower than normal, then there is less bone mass to begin with, making osteoporosis more likely to develop.<\/li>\r\n \t
- There is greater than normal bone resorption:<\/strong>\u00a0Bone resorption normally increases after peak bone mass is reached, but age-related bone resorption may be greater than normal for a variety of reasons. One possible reason is calcium or vitamin D deficiency, which causes the parathyroid gland to release PTH, the\u00a0hormone\u00a0that promotes resorption by osteoclasts.<\/li>\r\n \t
- There is inadequate formation of new bone by osteoblasts during remodeling:<\/strong>\u00a0Lack of estrogen may decrease the normal\u00a0deposition\u00a0of new bone. Inadequate levels of calcium and vitamin D also lead to impaired bone formation by osteoblasts.<\/li>\r\n<\/ol>\r\nAn imbalance between bone building and bone destruction leading to bone loss may also occur as a side effect of other disorders. For example, people with alcoholism, anorexia nervosa, or hyperthyroidism have an increased rate of bone loss. Some medications \u2014\u00a0including anti-seizure medications, chemotherapy drugs, steroid medications, and some antidepressants \u2014\u00a0also increase the rate of bone loss.\r\n
Diagnosing Osteoporosis<\/h2>\r\nOsteoporosis is diagnosed by measuring a patient\u2019s bone density and comparing it with the normal level of peak bone density in a young adult reference population of the same sex as the patient. If the patient\u2019s bone density is too far below the normal peak level (as measured by a statistic called a T-score), then osteoporosis is diagnosed. Bone density is usually measured by a type of X-ray called dual-energy X-ray absorptiometry (or DEXA), an example of which is shown in Figure 11.7.4. Typically, the density is measured at the hip. Sometimes, other areas are also measured, because there may be variation in bone density in different parts of the skeleton. Osteoporosis Canada\u00a0 recommends that all women 65 years of age and older be screened with DEXA for bone density. Screening may be recommended at younger ages in people with risk factors for osteoporosis (see Risk Factors for Osteoporosis below).\r\n\r\n[caption id=\"attachment_4126\" align=\"aligncenter\" width=\"530\"] Figure 11.7.4 Dual-energy X-ray absorptiometry is a means of measuring bone mineral density using spectral imaging. Two X-ray beams, with different energy levels, are aimed at the patient's bones. When soft tissue absorption is subtracted out, the bone mineral density can be determined from the absorption of each beam by bone.<\/em>[\/caption]\r\nOsteoporotic Fractures<\/h2>\r\nFractures are the most dangerous aspect of osteoporosis, and osteoporosis is responsible for millions of fractures annually. Debilitating pain among the elderly is often caused by fractures from osteoporosis, and it can lead to further disability and early mortality. Fractures of the long\u00a0bones\u00a0(such as the femur) can impair mobility and may require surgery. Hip fracture usually requires immediate surgery, as well. The immobility associated with fractures \u2014 especially of the hip \u2014 increases the risk of deep vein thrombosis, pulmonary embolism, and pneumonia. Osteoporosis is rarely fatal, but these complications of fractures often are. Older people tend to have more falls than younger people, due to such factors as poor eyesight and balance problems, increasing their risk of fractures even more. The likelihood of falls can be reduced by removing obstacles and loose carpets or rugs in the living environment.\r\nRisk Factors for Osteoporosis<\/h2>\r\nThere are a number of factors that increase the risk of osteoporosis. Eleven of them are listed below. The first five factors cannot be controlled, but the remaining factors generally can be controlled by changing behaviors.\r\n\r\n \t- Older age<\/li>\r\n \t
- Female sex<\/li>\r\n \t
- European or Asian ancestry<\/li>\r\n \t
- Family history of osteoporosis<\/li>\r\n \t
- Short stature and small bones<\/li>\r\n \t
- Smoking<\/li>\r\n \t
- Alcohol consumption<\/li>\r\n \t
- Lack of exercise<\/li>\r\n \t
- Vitamin D deficiency<\/li>\r\n \t
- Poor nutrition<\/li>\r\n \t
- Consumption of soft drinks<\/li>\r\n<\/ol>\r\n
Treatment and Prevention of Osteoporosis<\/h2>\r\nOsteoporosis is often treated with medications that may slow or even reverse bone loss. Medications called bisphosphonates, for example, are commonly prescribed.\u00a0Bisphosphonates slow down the breakdown of bone,\u00a0allowing\u00a0bone rebuilding during remodeling\u00a0to\u00a0keep pace. This helps maintain bone density and decreases the risk of fractures.\u00a0The medications may be more effective in patients who have already broken bones than in those who have not, significantly reducing their risk of another fracture. Generally, patients are not recommended to stay on bisphosphonates for more than three or four years. There is no evidence for continued benefit after this time \u2014 in fact, there is a potential for adverse side effects.\r\n\r\n[caption id=\"attachment_4128\" align=\"alignright\" width=\"491\"] Figure 11.7.5 Hiking is an enjoyable way to help keep bones strong and reduce the risk of osteoporosis.<\/em>[\/caption]\r\n\r\nPreventing osteoporosis includes eliminating any risk factors that can be controlled through changes of behavior. If you smoke, stop. If you drink, reduce your alcohol consumption \u2014 or cut it out altogether. Eat a nutritious diet and make sure you are getting adequate amounts of vitamin D. You should also avoid drinking carbonated beverages.\r\n\r\n \r\n\r\nIf you\u2019re a couch potato, get involved in regular exercise. Aerobic, weight-bearing, and resistance exercises can all help maintain or increase bone mineral density (for example hiking as in Figure 11.7.5). Exercise puts stress on bones, which stimulates bone building. Good weight-bearing exercises for bone building include weight training, dancing, stair climbing, running, and hiking (see Figure 11.7.5). Biking and swimming are less beneficial, because they don\u2019t stress the bones. Ideally, you should exercise for at least 30 minutes a day most days of the week.\r\n\r\n \r\nOsteoarthritis<\/span><\/div>\r\n \r\n\r\n[caption id=\"attachment_4129\" align=\"alignleft\" width=\"161\"] Figure 11.7.6 The areas shaded in blue indicate the joints most commonly affected by OA.<\/em>[\/caption]\r\n\r\n[pb_glossary id=\"4102\"]Osteoarthritis[\/pb_glossary] (OA<\/a>)<\/strong> is a joint disease that results from the breakdown of joint cartilage and bone. The most common symptoms are joint pain and stiffness. Other symptoms may include joint swelling and decreased range of motion. Initially, symptoms may occur only after exercise or prolonged activity, but over time, they may become constant, negatively affecting work and normal daily activities. As shown in Figure 11.7.6, the most commonly involved joints are those near the ends of the fingers, at the bases of the thumbs, and in the neck, lower back, hips, and knees. Often, joints on one side of the body are affected more than those on the other side.\r\n\r\n \r\nWhat Causes Osteoarthritis?<\/h2>\r\nOA is thought to be caused by mechanical stress on the\u00a0joints\u00a0with insufficient self-repair of cartilage. The stress may be exacerbated by low-grade inflammation of the joints, as\u00a0cells\u00a0lining the joint attempt to remove breakdown products from cartilage in the synovial space. OA develops over decades as stress and inflammation cause increasing loss of articular cartilage. Eventually, bones may have no cartilage to separate them, so bones rub against one another at joints. This damages the articular surfaces of the bones and contributes to the pain and other symptoms of OA. Because of the pain, movement may be curtailed, leading to loss of muscle, as well.\r\nDiagnosing Osteoarthritis<\/h2>\r\n[caption id=\"attachment_4131\" align=\"alignright\" width=\"300\"] Figure 11.7.7 A bunion is a common sign of osteoarthritis. It is typically located at the base of the big toe.<\/em>[\/caption]\r\n\r\nDiagnosis of OA is typically made on the basis of signs and symptoms. Signs include joint deformities, such as bony nodules on the finger joints or bunions on the feet (as illustrated in Figure 11.7.7). Symptoms include joint pain and stiffness. The pain is usually described as a sharp ache or burning sensation, which may be in the muscles and tendons around the affected joints, as well as in the joints themselves. The pain is usually made worse by prolonged activity, and it typically improves with rest. Stiffness is most common when first arising in the morning, and it usually improves quickly as daily activities are undertaken.\r\n\r\nX-rays\u00a0or other tests are sometimes used to either support the diagnosis of OA or to rule out other disorders.\u00a0Blood tests might be done, for example, to look for factors that indicate rheumatoid arthritis (RA), an\u00a0autoimmune disease\u00a0in which the immune system attacks the body\u2019s joints. If these factors are not present in the\u00a0blood, then RA is unlikely, and a diagnosis of OA is more likely to be correct.\r\nRisk Factors for Osteoarthritis<\/h2>\r\nAge is the chief risk factor for osteoarthritis. By age 65, as many as 80 per cent of all people have evidence of osteoarthritis. However, people are more likely to develop OA \u2014 especially at younger ages \u2014 if they have had a joint injury. A high school football player might have a bad knee injury that damages the joint, leading to OA in the knee by the time he is in his thirties. If people have joints that are misaligned due to congenital malformations or disease, they are also more likely to develop OA. Excess body weight is another factor that increases the risk of OA, because of the added stress it places on weight-bearing joints.\r\n\r\nResearchers have found that people with a family history of OA have a heightened risk of developing the disorder, which suggests that genetic factors are also involved in OA. It is likely that many different genes are needed for normal cartilage and cartilage repair. If such genes are defective and cartilage is abnormal or not normally repaired, OA is more likely to result.\r\nTreatment and Prevention of Osteoarthritis<\/h2>\r\nOA cannot be cured, but the symptoms \u2014 especially the pain \u2014 can often be treated successfully to maintain good quality of life for people with OA. Treatments include exercise, efforts to decrease stress on joints, pain medications, and surgery.\r\nExercise<\/h3>\r\nExercise helps maintain joint mobility and also increases muscle strength. Stronger muscles may help keep the bones in joints correctly aligned, and this can reduce joint stress. Good exercises for OA include swimming, water aerobics (see Figure 11.7.8 below), and biking. These activities are recommended for OA, because they put relatively little stress on the joints.\r\n\r\n[caption id=\"attachment_4133\" align=\"aligncenter\" width=\"1000\"] Figure 11.7.8 Exercising in water provides buoyancy that places less stress on joints than the same exercises would on the ground or other hard surface.<\/em>[\/caption]\r\n\r\n\r\n\r\nExercising in water provides buoyancy that places less stress on joints than the same exercises would on the ground or other hard surface.\r\n\r\n<\/div>\r\nDe-stressing Joints<\/h3>\r\nEfforts to decrease stress on joints include resting and using mobility devices such as canes, which reduce the\u00a0weight\u00a0placed on weight-bearing joints and also improve stability. In people who are overweight, losing weight may also reduce joint stress.\r\nPain Medications<\/h3>\r\nThe first type of pain medication likely to be prescribed for OA is acetaminophen (e.g., Tylenol). When taken as prescribed, it has a relatively low risk of serious side effects. If this medication is inadequate to relieve the pain, non-steroidal anti-inflammatory drugs (NSAIDs, such as ibuprofen) may be prescribed. NSAIDs, however, are more likely to cause serious side effects, such as gastrointestinal bleeding, elevated\u00a0blood pressure, and increased risk of stroke. Opioids usually are reserved for patients who have suffered serious side effects or for whom other medications have failed to relieve pain. Due to the risk of [pb_glossary id=\"3184\"]addiction[\/pb_glossary], only short-term use of opioids is generally recommended.\r\nSurgery<\/h3>\r\nJoint-replacement surgery is the most common treatment for serious OA in the knee or hip. In fact, knee and hip replacement surgeries are among the most common of all surgeries. Although they require a long period of healing and physical rehabilitation, the results are usually worth it. The replacement \u201cparts\u201d are usually pain-free and fully functional for at least a couple of decades. Quality, durability, and customization of artificial joints are constantly improving.\r\n\r\nTry out this neat Virtual Hip Resurfacing<\/a> activity by Edheads (you will need to enable Flash).\r\n\r\nFeature: Myth vs. Reality<\/span>\r\n\r\nAbout one out of every 5 adults in Canada suffer from\u00a0 osteoarthritis. The more you know about this disease, the more you can do to avoid it or slow its progression. That means knowing the facts, rather than believing the myths about osteoarthritis.\r\n
Osteoporosis<\/h1>\r\n<\/div>\r\n[pb_glossary id=\"4122\"]Osteoporosis[\/pb_glossary]<\/strong> is an age-related disorder in which bones lose mass, weaken, and break more easily than normal bones. Bones may weaken so much that a fracture can occur with minor stress \u2014 or even spontaneously, without any stress at all. Osteoporosis is the most common cause of broken bones in the elderly, but until a bone fracture occurs, it typically causes no symptoms. The bones that break most often include those in the wrist, hip, shoulder, and spine. When the thoracic vertebrae are affected, there can be a gradual collapse of the vertebrae due to compression fractures, as shown in Figure 11.7.2. This is what causes kyphosis, as pictured above in Figure 11.7.1.\r\n\r\n[caption id=\"attachment_4123\" align=\"aligncenter\" width=\"400\"] Figure 11.7.2 Compression fractures of thoracic vertebrae are relatively common in people with osteoporosis.<\/em>[\/caption]\r\nChanges in Bone Mass with Age<\/h2>\r\nAs shown in the Figure 11.7.3, bone mass in both males and females generally peaks when people are in their thirties, with males typically attaining a higher peak mass than females. In both sexes, bone mass usually decreases after that, and this tends to occur more rapidly in females, especially after menopause. The greater decrease in females is generally attributable to low levels of estrogen in the post-menopausal years.\r\n\r\n[caption id=\"attachment_4124\" align=\"aligncenter\" width=\"860\"] Figure 11.7.3 Bone mass is a measure of the total mass of calcium in the bones of the skeleton. As bone mass decreases, the risk of fractures increases.<\/em>[\/caption]\r\nWhat Causes Osteoporosis?<\/h2>\r\nThe underlying mechanism in all cases of osteoporosis is an imbalance between bone formation by [pb_glossary id=\"4040\"]osteoblasts[\/pb_glossary] and bone resorption by [pb_glossary id=\"4042\"]osteoclasts[\/pb_glossary]. Normally, bones are constantly being remodeled by these two processes, with up to ten per cent of all bone mass undergoing remodeling at any point in time. As long as these two processes are in balance, no net loss<\/em> of bone occurs. There are three main ways that an imbalance between bone formation and bone resorption can occur and lead to a net loss of bone. All three ways may occur in the same individual. The three ways are described below:\r\n\r\n \t- \u00a0An individual never develops normal peak bone mass during the young adult years:<\/strong>\u00a0If the peak level is lower than normal, then there is less bone mass to begin with, making osteoporosis more likely to develop.<\/li>\r\n \t
- There is greater than normal bone resorption:<\/strong>\u00a0Bone resorption normally increases after peak bone mass is reached, but age-related bone resorption may be greater than normal for a variety of reasons. One possible reason is calcium or vitamin D deficiency, which causes the parathyroid gland to release PTH, the\u00a0hormone\u00a0that promotes resorption by osteoclasts.<\/li>\r\n \t
- There is inadequate formation of new bone by osteoblasts during remodeling:<\/strong>\u00a0Lack of estrogen may decrease the normal\u00a0deposition\u00a0of new bone. Inadequate levels of calcium and vitamin D also lead to impaired bone formation by osteoblasts.<\/li>\r\n<\/ol>\r\nAn imbalance between bone building and bone destruction leading to bone loss may also occur as a side effect of other disorders. For example, people with alcoholism, anorexia nervosa, or hyperthyroidism have an increased rate of bone loss. Some medications \u2014\u00a0including anti-seizure medications, chemotherapy drugs, steroid medications, and some antidepressants \u2014\u00a0also increase the rate of bone loss.\r\n
Diagnosing Osteoporosis<\/h2>\r\nOsteoporosis is diagnosed by measuring a patient\u2019s bone density and comparing it with the normal level of peak bone density in a young adult reference population of the same sex as the patient. If the patient\u2019s bone density is too far below the normal peak level (as measured by a statistic called a T-score), then osteoporosis is diagnosed. Bone density is usually measured by a type of X-ray called dual-energy X-ray absorptiometry (or DEXA), an example of which is shown in Figure 11.7.4. Typically, the density is measured at the hip. Sometimes, other areas are also measured, because there may be variation in bone density in different parts of the skeleton. Osteoporosis Canada\u00a0 recommends that all women 65 years of age and older be screened with DEXA for bone density. Screening may be recommended at younger ages in people with risk factors for osteoporosis (see Risk Factors for Osteoporosis below).\r\n\r\n[caption id=\"attachment_4126\" align=\"aligncenter\" width=\"530\"] Figure 11.7.4 Dual-energy X-ray absorptiometry is a means of measuring bone mineral density using spectral imaging. Two X-ray beams, with different energy levels, are aimed at the patient's bones. When soft tissue absorption is subtracted out, the bone mineral density can be determined from the absorption of each beam by bone.<\/em>[\/caption]\r\nOsteoporotic Fractures<\/h2>\r\nFractures are the most dangerous aspect of osteoporosis, and osteoporosis is responsible for millions of fractures annually. Debilitating pain among the elderly is often caused by fractures from osteoporosis, and it can lead to further disability and early mortality. Fractures of the long\u00a0bones\u00a0(such as the femur) can impair mobility and may require surgery. Hip fracture usually requires immediate surgery, as well. The immobility associated with fractures \u2014 especially of the hip \u2014 increases the risk of deep vein thrombosis, pulmonary embolism, and pneumonia. Osteoporosis is rarely fatal, but these complications of fractures often are. Older people tend to have more falls than younger people, due to such factors as poor eyesight and balance problems, increasing their risk of fractures even more. The likelihood of falls can be reduced by removing obstacles and loose carpets or rugs in the living environment.\r\nRisk Factors for Osteoporosis<\/h2>\r\nThere are a number of factors that increase the risk of osteoporosis. Eleven of them are listed below. The first five factors cannot be controlled, but the remaining factors generally can be controlled by changing behaviors.\r\n\r\n \t- Older age<\/li>\r\n \t
- Female sex<\/li>\r\n \t
- European or Asian ancestry<\/li>\r\n \t
- Family history of osteoporosis<\/li>\r\n \t
- Short stature and small bones<\/li>\r\n \t
- Smoking<\/li>\r\n \t
- Alcohol consumption<\/li>\r\n \t
- Lack of exercise<\/li>\r\n \t
- Vitamin D deficiency<\/li>\r\n \t
- Poor nutrition<\/li>\r\n \t
- Consumption of soft drinks<\/li>\r\n<\/ol>\r\n
Treatment and Prevention of Osteoporosis<\/h2>\r\nOsteoporosis is often treated with medications that may slow or even reverse bone loss. Medications called bisphosphonates, for example, are commonly prescribed.\u00a0Bisphosphonates slow down the breakdown of bone,\u00a0allowing\u00a0bone rebuilding during remodeling\u00a0to\u00a0keep pace. This helps maintain bone density and decreases the risk of fractures.\u00a0The medications may be more effective in patients who have already broken bones than in those who have not, significantly reducing their risk of another fracture. Generally, patients are not recommended to stay on bisphosphonates for more than three or four years. There is no evidence for continued benefit after this time \u2014 in fact, there is a potential for adverse side effects.\r\n\r\n[caption id=\"attachment_4128\" align=\"alignright\" width=\"491\"] Figure 11.7.5 Hiking is an enjoyable way to help keep bones strong and reduce the risk of osteoporosis.<\/em>[\/caption]\r\n\r\nPreventing osteoporosis includes eliminating any risk factors that can be controlled through changes of behavior. If you smoke, stop. If you drink, reduce your alcohol consumption \u2014 or cut it out altogether. Eat a nutritious diet and make sure you are getting adequate amounts of vitamin D. You should also avoid drinking carbonated beverages.\r\n\r\n \r\n\r\nIf you\u2019re a couch potato, get involved in regular exercise. Aerobic, weight-bearing, and resistance exercises can all help maintain or increase bone mineral density (for example hiking as in Figure 11.7.5). Exercise puts stress on bones, which stimulates bone building. Good weight-bearing exercises for bone building include weight training, dancing, stair climbing, running, and hiking (see Figure 11.7.5). Biking and swimming are less beneficial, because they don\u2019t stress the bones. Ideally, you should exercise for at least 30 minutes a day most days of the week.\r\n\r\n \r\nOsteoarthritis<\/span><\/div>\r\n \r\n\r\n[caption id=\"attachment_4129\" align=\"alignleft\" width=\"161\"] Figure 11.7.6 The areas shaded in blue indicate the joints most commonly affected by OA.<\/em>[\/caption]\r\n\r\n[pb_glossary id=\"4102\"]Osteoarthritis[\/pb_glossary] (OA<\/a>)<\/strong> is a joint disease that results from the breakdown of joint cartilage and bone. The most common symptoms are joint pain and stiffness. Other symptoms may include joint swelling and decreased range of motion. Initially, symptoms may occur only after exercise or prolonged activity, but over time, they may become constant, negatively affecting work and normal daily activities. As shown in Figure 11.7.6, the most commonly involved joints are those near the ends of the fingers, at the bases of the thumbs, and in the neck, lower back, hips, and knees. Often, joints on one side of the body are affected more than those on the other side.\r\n\r\n \r\nWhat Causes Osteoarthritis?<\/h2>\r\nOA is thought to be caused by mechanical stress on the\u00a0joints\u00a0with insufficient self-repair of cartilage. The stress may be exacerbated by low-grade inflammation of the joints, as\u00a0cells\u00a0lining the joint attempt to remove breakdown products from cartilage in the synovial space. OA develops over decades as stress and inflammation cause increasing loss of articular cartilage. Eventually, bones may have no cartilage to separate them, so bones rub against one another at joints. This damages the articular surfaces of the bones and contributes to the pain and other symptoms of OA. Because of the pain, movement may be curtailed, leading to loss of muscle, as well.\r\nDiagnosing Osteoarthritis<\/h2>\r\n[caption id=\"attachment_4131\" align=\"alignright\" width=\"300\"] Figure 11.7.7 A bunion is a common sign of osteoarthritis. It is typically located at the base of the big toe.<\/em>[\/caption]\r\n\r\nDiagnosis of OA is typically made on the basis of signs and symptoms. Signs include joint deformities, such as bony nodules on the finger joints or bunions on the feet (as illustrated in Figure 11.7.7). Symptoms include joint pain and stiffness. The pain is usually described as a sharp ache or burning sensation, which may be in the muscles and tendons around the affected joints, as well as in the joints themselves. The pain is usually made worse by prolonged activity, and it typically improves with rest. Stiffness is most common when first arising in the morning, and it usually improves quickly as daily activities are undertaken.\r\n\r\nX-rays\u00a0or other tests are sometimes used to either support the diagnosis of OA or to rule out other disorders.\u00a0Blood tests might be done, for example, to look for factors that indicate rheumatoid arthritis (RA), an\u00a0autoimmune disease\u00a0in which the immune system attacks the body\u2019s joints. If these factors are not present in the\u00a0blood, then RA is unlikely, and a diagnosis of OA is more likely to be correct.\r\nRisk Factors for Osteoarthritis<\/h2>\r\nAge is the chief risk factor for osteoarthritis. By age 65, as many as 80 per cent of all people have evidence of osteoarthritis. However, people are more likely to develop OA \u2014 especially at younger ages \u2014 if they have had a joint injury. A high school football player might have a bad knee injury that damages the joint, leading to OA in the knee by the time he is in his thirties. If people have joints that are misaligned due to congenital malformations or disease, they are also more likely to develop OA. Excess body weight is another factor that increases the risk of OA, because of the added stress it places on weight-bearing joints.\r\n\r\nResearchers have found that people with a family history of OA have a heightened risk of developing the disorder, which suggests that genetic factors are also involved in OA. It is likely that many different genes are needed for normal cartilage and cartilage repair. If such genes are defective and cartilage is abnormal or not normally repaired, OA is more likely to result.\r\nTreatment and Prevention of Osteoarthritis<\/h2>\r\nOA cannot be cured, but the symptoms \u2014 especially the pain \u2014 can often be treated successfully to maintain good quality of life for people with OA. Treatments include exercise, efforts to decrease stress on joints, pain medications, and surgery.\r\nExercise<\/h3>\r\nExercise helps maintain joint mobility and also increases muscle strength. Stronger muscles may help keep the bones in joints correctly aligned, and this can reduce joint stress. Good exercises for OA include swimming, water aerobics (see Figure 11.7.8 below), and biking. These activities are recommended for OA, because they put relatively little stress on the joints.\r\n\r\n[caption id=\"attachment_4133\" align=\"aligncenter\" width=\"1000\"] Figure 11.7.8 Exercising in water provides buoyancy that places less stress on joints than the same exercises would on the ground or other hard surface.<\/em>[\/caption]\r\n\r\n\r\n\r\nExercising in water provides buoyancy that places less stress on joints than the same exercises would on the ground or other hard surface.\r\n\r\n<\/div>\r\nDe-stressing Joints<\/h3>\r\nEfforts to decrease stress on joints include resting and using mobility devices such as canes, which reduce the\u00a0weight\u00a0placed on weight-bearing joints and also improve stability. In people who are overweight, losing weight may also reduce joint stress.\r\nPain Medications<\/h3>\r\nThe first type of pain medication likely to be prescribed for OA is acetaminophen (e.g., Tylenol). When taken as prescribed, it has a relatively low risk of serious side effects. If this medication is inadequate to relieve the pain, non-steroidal anti-inflammatory drugs (NSAIDs, such as ibuprofen) may be prescribed. NSAIDs, however, are more likely to cause serious side effects, such as gastrointestinal bleeding, elevated\u00a0blood pressure, and increased risk of stroke. Opioids usually are reserved for patients who have suffered serious side effects or for whom other medications have failed to relieve pain. Due to the risk of [pb_glossary id=\"3184\"]addiction[\/pb_glossary], only short-term use of opioids is generally recommended.\r\nSurgery<\/h3>\r\nJoint-replacement surgery is the most common treatment for serious OA in the knee or hip. In fact, knee and hip replacement surgeries are among the most common of all surgeries. Although they require a long period of healing and physical rehabilitation, the results are usually worth it. The replacement \u201cparts\u201d are usually pain-free and fully functional for at least a couple of decades. Quality, durability, and customization of artificial joints are constantly improving.\r\n\r\nTry out this neat Virtual Hip Resurfacing<\/a> activity by Edheads (you will need to enable Flash).\r\n\r\nFeature: Myth vs. Reality<\/span>\r\n\r\nAbout one out of every 5 adults in Canada suffer from\u00a0 osteoarthritis. The more you know about this disease, the more you can do to avoid it or slow its progression. That means knowing the facts, rather than believing the myths about osteoarthritis.\r\n
Figure 11.7.3 Bone mass is a measure of the total mass of calcium in the bones of the skeleton. As bone mass decreases, the risk of fractures increases.<\/em>[\/caption]\r\nWhat Causes Osteoporosis?<\/h2>\r\nThe underlying mechanism in all cases of osteoporosis is an imbalance between bone formation by [pb_glossary id=\"4040\"]osteoblasts[\/pb_glossary] and bone resorption by [pb_glossary id=\"4042\"]osteoclasts[\/pb_glossary]. Normally, bones are constantly being remodeled by these two processes, with up to ten per cent of all bone mass undergoing remodeling at any point in time. As long as these two processes are in balance, no net loss<\/em> of bone occurs. There are three main ways that an imbalance between bone formation and bone resorption can occur and lead to a net loss of bone. All three ways may occur in the same individual. The three ways are described below:\r\n\r\n \t- \u00a0An individual never develops normal peak bone mass during the young adult years:<\/strong>\u00a0If the peak level is lower than normal, then there is less bone mass to begin with, making osteoporosis more likely to develop.<\/li>\r\n \t
- There is greater than normal bone resorption:<\/strong>\u00a0Bone resorption normally increases after peak bone mass is reached, but age-related bone resorption may be greater than normal for a variety of reasons. One possible reason is calcium or vitamin D deficiency, which causes the parathyroid gland to release PTH, the\u00a0hormone\u00a0that promotes resorption by osteoclasts.<\/li>\r\n \t
- There is inadequate formation of new bone by osteoblasts during remodeling:<\/strong>\u00a0Lack of estrogen may decrease the normal\u00a0deposition\u00a0of new bone. Inadequate levels of calcium and vitamin D also lead to impaired bone formation by osteoblasts.<\/li>\r\n<\/ol>\r\nAn imbalance between bone building and bone destruction leading to bone loss may also occur as a side effect of other disorders. For example, people with alcoholism, anorexia nervosa, or hyperthyroidism have an increased rate of bone loss. Some medications \u2014\u00a0including anti-seizure medications, chemotherapy drugs, steroid medications, and some antidepressants \u2014\u00a0also increase the rate of bone loss.\r\n
Diagnosing Osteoporosis<\/h2>\r\nOsteoporosis is diagnosed by measuring a patient\u2019s bone density and comparing it with the normal level of peak bone density in a young adult reference population of the same sex as the patient. If the patient\u2019s bone density is too far below the normal peak level (as measured by a statistic called a T-score), then osteoporosis is diagnosed. Bone density is usually measured by a type of X-ray called dual-energy X-ray absorptiometry (or DEXA), an example of which is shown in Figure 11.7.4. Typically, the density is measured at the hip. Sometimes, other areas are also measured, because there may be variation in bone density in different parts of the skeleton. Osteoporosis Canada\u00a0 recommends that all women 65 years of age and older be screened with DEXA for bone density. Screening may be recommended at younger ages in people with risk factors for osteoporosis (see Risk Factors for Osteoporosis below).\r\n\r\n[caption id=\"attachment_4126\" align=\"aligncenter\" width=\"530\"] Figure 11.7.4 Dual-energy X-ray absorptiometry is a means of measuring bone mineral density using spectral imaging. Two X-ray beams, with different energy levels, are aimed at the patient's bones. When soft tissue absorption is subtracted out, the bone mineral density can be determined from the absorption of each beam by bone.<\/em>[\/caption]\r\nOsteoporotic Fractures<\/h2>\r\nFractures are the most dangerous aspect of osteoporosis, and osteoporosis is responsible for millions of fractures annually. Debilitating pain among the elderly is often caused by fractures from osteoporosis, and it can lead to further disability and early mortality. Fractures of the long\u00a0bones\u00a0(such as the femur) can impair mobility and may require surgery. Hip fracture usually requires immediate surgery, as well. The immobility associated with fractures \u2014 especially of the hip \u2014 increases the risk of deep vein thrombosis, pulmonary embolism, and pneumonia. Osteoporosis is rarely fatal, but these complications of fractures often are. Older people tend to have more falls than younger people, due to such factors as poor eyesight and balance problems, increasing their risk of fractures even more. The likelihood of falls can be reduced by removing obstacles and loose carpets or rugs in the living environment.\r\nRisk Factors for Osteoporosis<\/h2>\r\nThere are a number of factors that increase the risk of osteoporosis. Eleven of them are listed below. The first five factors cannot be controlled, but the remaining factors generally can be controlled by changing behaviors.\r\n\r\n \t- Older age<\/li>\r\n \t
- Female sex<\/li>\r\n \t
- European or Asian ancestry<\/li>\r\n \t
- Family history of osteoporosis<\/li>\r\n \t
- Short stature and small bones<\/li>\r\n \t
- Smoking<\/li>\r\n \t
- Alcohol consumption<\/li>\r\n \t
- Lack of exercise<\/li>\r\n \t
- Vitamin D deficiency<\/li>\r\n \t
- Poor nutrition<\/li>\r\n \t
- Consumption of soft drinks<\/li>\r\n<\/ol>\r\n
Treatment and Prevention of Osteoporosis<\/h2>\r\nOsteoporosis is often treated with medications that may slow or even reverse bone loss. Medications called bisphosphonates, for example, are commonly prescribed.\u00a0Bisphosphonates slow down the breakdown of bone,\u00a0allowing\u00a0bone rebuilding during remodeling\u00a0to\u00a0keep pace. This helps maintain bone density and decreases the risk of fractures.\u00a0The medications may be more effective in patients who have already broken bones than in those who have not, significantly reducing their risk of another fracture. Generally, patients are not recommended to stay on bisphosphonates for more than three or four years. There is no evidence for continued benefit after this time \u2014 in fact, there is a potential for adverse side effects.\r\n\r\n[caption id=\"attachment_4128\" align=\"alignright\" width=\"491\"] Figure 11.7.5 Hiking is an enjoyable way to help keep bones strong and reduce the risk of osteoporosis.<\/em>[\/caption]\r\n\r\nPreventing osteoporosis includes eliminating any risk factors that can be controlled through changes of behavior. If you smoke, stop. If you drink, reduce your alcohol consumption \u2014 or cut it out altogether. Eat a nutritious diet and make sure you are getting adequate amounts of vitamin D. You should also avoid drinking carbonated beverages.\r\n\r\n \r\n\r\nIf you\u2019re a couch potato, get involved in regular exercise. Aerobic, weight-bearing, and resistance exercises can all help maintain or increase bone mineral density (for example hiking as in Figure 11.7.5). Exercise puts stress on bones, which stimulates bone building. Good weight-bearing exercises for bone building include weight training, dancing, stair climbing, running, and hiking (see Figure 11.7.5). Biking and swimming are less beneficial, because they don\u2019t stress the bones. Ideally, you should exercise for at least 30 minutes a day most days of the week.\r\n\r\n \r\nOsteoarthritis<\/span><\/div>\r\n \r\n\r\n[caption id=\"attachment_4129\" align=\"alignleft\" width=\"161\"] Figure 11.7.6 The areas shaded in blue indicate the joints most commonly affected by OA.<\/em>[\/caption]\r\n\r\n[pb_glossary id=\"4102\"]Osteoarthritis[\/pb_glossary] (OA<\/a>)<\/strong> is a joint disease that results from the breakdown of joint cartilage and bone. The most common symptoms are joint pain and stiffness. Other symptoms may include joint swelling and decreased range of motion. Initially, symptoms may occur only after exercise or prolonged activity, but over time, they may become constant, negatively affecting work and normal daily activities. As shown in Figure 11.7.6, the most commonly involved joints are those near the ends of the fingers, at the bases of the thumbs, and in the neck, lower back, hips, and knees. Often, joints on one side of the body are affected more than those on the other side.\r\n\r\n \r\nWhat Causes Osteoarthritis?<\/h2>\r\nOA is thought to be caused by mechanical stress on the\u00a0joints\u00a0with insufficient self-repair of cartilage. The stress may be exacerbated by low-grade inflammation of the joints, as\u00a0cells\u00a0lining the joint attempt to remove breakdown products from cartilage in the synovial space. OA develops over decades as stress and inflammation cause increasing loss of articular cartilage. Eventually, bones may have no cartilage to separate them, so bones rub against one another at joints. This damages the articular surfaces of the bones and contributes to the pain and other symptoms of OA. Because of the pain, movement may be curtailed, leading to loss of muscle, as well.\r\nDiagnosing Osteoarthritis<\/h2>\r\n[caption id=\"attachment_4131\" align=\"alignright\" width=\"300\"] Figure 11.7.7 A bunion is a common sign of osteoarthritis. It is typically located at the base of the big toe.<\/em>[\/caption]\r\n\r\nDiagnosis of OA is typically made on the basis of signs and symptoms. Signs include joint deformities, such as bony nodules on the finger joints or bunions on the feet (as illustrated in Figure 11.7.7). Symptoms include joint pain and stiffness. The pain is usually described as a sharp ache or burning sensation, which may be in the muscles and tendons around the affected joints, as well as in the joints themselves. The pain is usually made worse by prolonged activity, and it typically improves with rest. Stiffness is most common when first arising in the morning, and it usually improves quickly as daily activities are undertaken.\r\n\r\nX-rays\u00a0or other tests are sometimes used to either support the diagnosis of OA or to rule out other disorders.\u00a0Blood tests might be done, for example, to look for factors that indicate rheumatoid arthritis (RA), an\u00a0autoimmune disease\u00a0in which the immune system attacks the body\u2019s joints. If these factors are not present in the\u00a0blood, then RA is unlikely, and a diagnosis of OA is more likely to be correct.\r\nRisk Factors for Osteoarthritis<\/h2>\r\nAge is the chief risk factor for osteoarthritis. By age 65, as many as 80 per cent of all people have evidence of osteoarthritis. However, people are more likely to develop OA \u2014 especially at younger ages \u2014 if they have had a joint injury. A high school football player might have a bad knee injury that damages the joint, leading to OA in the knee by the time he is in his thirties. If people have joints that are misaligned due to congenital malformations or disease, they are also more likely to develop OA. Excess body weight is another factor that increases the risk of OA, because of the added stress it places on weight-bearing joints.\r\n\r\nResearchers have found that people with a family history of OA have a heightened risk of developing the disorder, which suggests that genetic factors are also involved in OA. It is likely that many different genes are needed for normal cartilage and cartilage repair. If such genes are defective and cartilage is abnormal or not normally repaired, OA is more likely to result.\r\nTreatment and Prevention of Osteoarthritis<\/h2>\r\nOA cannot be cured, but the symptoms \u2014 especially the pain \u2014 can often be treated successfully to maintain good quality of life for people with OA. Treatments include exercise, efforts to decrease stress on joints, pain medications, and surgery.\r\nExercise<\/h3>\r\nExercise helps maintain joint mobility and also increases muscle strength. Stronger muscles may help keep the bones in joints correctly aligned, and this can reduce joint stress. Good exercises for OA include swimming, water aerobics (see Figure 11.7.8 below), and biking. These activities are recommended for OA, because they put relatively little stress on the joints.\r\n\r\n[caption id=\"attachment_4133\" align=\"aligncenter\" width=\"1000\"] Figure 11.7.8 Exercising in water provides buoyancy that places less stress on joints than the same exercises would on the ground or other hard surface.<\/em>[\/caption]\r\n\r\n\r\n\r\nExercising in water provides buoyancy that places less stress on joints than the same exercises would on the ground or other hard surface.\r\n\r\n<\/div>\r\nDe-stressing Joints<\/h3>\r\nEfforts to decrease stress on joints include resting and using mobility devices such as canes, which reduce the\u00a0weight\u00a0placed on weight-bearing joints and also improve stability. In people who are overweight, losing weight may also reduce joint stress.\r\nPain Medications<\/h3>\r\nThe first type of pain medication likely to be prescribed for OA is acetaminophen (e.g., Tylenol). When taken as prescribed, it has a relatively low risk of serious side effects. If this medication is inadequate to relieve the pain, non-steroidal anti-inflammatory drugs (NSAIDs, such as ibuprofen) may be prescribed. NSAIDs, however, are more likely to cause serious side effects, such as gastrointestinal bleeding, elevated\u00a0blood pressure, and increased risk of stroke. Opioids usually are reserved for patients who have suffered serious side effects or for whom other medications have failed to relieve pain. Due to the risk of [pb_glossary id=\"3184\"]addiction[\/pb_glossary], only short-term use of opioids is generally recommended.\r\nSurgery<\/h3>\r\nJoint-replacement surgery is the most common treatment for serious OA in the knee or hip. In fact, knee and hip replacement surgeries are among the most common of all surgeries. Although they require a long period of healing and physical rehabilitation, the results are usually worth it. The replacement \u201cparts\u201d are usually pain-free and fully functional for at least a couple of decades. Quality, durability, and customization of artificial joints are constantly improving.\r\n\r\nTry out this neat Virtual Hip Resurfacing<\/a> activity by Edheads (you will need to enable Flash).\r\n\r\nFeature: Myth vs. Reality<\/span>\r\n\r\nAbout one out of every 5 adults in Canada suffer from\u00a0 osteoarthritis. The more you know about this disease, the more you can do to avoid it or slow its progression. That means knowing the facts, rather than believing the myths about osteoarthritis.\r\n
Diagnosing Osteoporosis<\/h2>\r\nOsteoporosis is diagnosed by measuring a patient\u2019s bone density and comparing it with the normal level of peak bone density in a young adult reference population of the same sex as the patient. If the patient\u2019s bone density is too far below the normal peak level (as measured by a statistic called a T-score), then osteoporosis is diagnosed. Bone density is usually measured by a type of X-ray called dual-energy X-ray absorptiometry (or DEXA), an example of which is shown in Figure 11.7.4. Typically, the density is measured at the hip. Sometimes, other areas are also measured, because there may be variation in bone density in different parts of the skeleton. Osteoporosis Canada\u00a0 recommends that all women 65 years of age and older be screened with DEXA for bone density. Screening may be recommended at younger ages in people with risk factors for osteoporosis (see Risk Factors for Osteoporosis below).\r\n\r\n[caption id=\"attachment_4126\" align=\"aligncenter\" width=\"530\"] Figure 11.7.4 Dual-energy X-ray absorptiometry is a means of measuring bone mineral density using spectral imaging. Two X-ray beams, with different energy levels, are aimed at the patient's bones. When soft tissue absorption is subtracted out, the bone mineral density can be determined from the absorption of each beam by bone.<\/em>[\/caption]\r\nOsteoporotic Fractures<\/h2>\r\nFractures are the most dangerous aspect of osteoporosis, and osteoporosis is responsible for millions of fractures annually. Debilitating pain among the elderly is often caused by fractures from osteoporosis, and it can lead to further disability and early mortality. Fractures of the long\u00a0bones\u00a0(such as the femur) can impair mobility and may require surgery. Hip fracture usually requires immediate surgery, as well. The immobility associated with fractures \u2014 especially of the hip \u2014 increases the risk of deep vein thrombosis, pulmonary embolism, and pneumonia. Osteoporosis is rarely fatal, but these complications of fractures often are. Older people tend to have more falls than younger people, due to such factors as poor eyesight and balance problems, increasing their risk of fractures even more. The likelihood of falls can be reduced by removing obstacles and loose carpets or rugs in the living environment.\r\nRisk Factors for Osteoporosis<\/h2>\r\nThere are a number of factors that increase the risk of osteoporosis. Eleven of them are listed below. The first five factors cannot be controlled, but the remaining factors generally can be controlled by changing behaviors.\r\n\r\n \t- Older age<\/li>\r\n \t
- Female sex<\/li>\r\n \t
- European or Asian ancestry<\/li>\r\n \t
- Family history of osteoporosis<\/li>\r\n \t
- Short stature and small bones<\/li>\r\n \t
- Smoking<\/li>\r\n \t
- Alcohol consumption<\/li>\r\n \t
- Lack of exercise<\/li>\r\n \t
- Vitamin D deficiency<\/li>\r\n \t
- Poor nutrition<\/li>\r\n \t
- Consumption of soft drinks<\/li>\r\n<\/ol>\r\n
Treatment and Prevention of Osteoporosis<\/h2>\r\nOsteoporosis is often treated with medications that may slow or even reverse bone loss. Medications called bisphosphonates, for example, are commonly prescribed.\u00a0Bisphosphonates slow down the breakdown of bone,\u00a0allowing\u00a0bone rebuilding during remodeling\u00a0to\u00a0keep pace. This helps maintain bone density and decreases the risk of fractures.\u00a0The medications may be more effective in patients who have already broken bones than in those who have not, significantly reducing their risk of another fracture. Generally, patients are not recommended to stay on bisphosphonates for more than three or four years. There is no evidence for continued benefit after this time \u2014 in fact, there is a potential for adverse side effects.\r\n\r\n[caption id=\"attachment_4128\" align=\"alignright\" width=\"491\"] Figure 11.7.5 Hiking is an enjoyable way to help keep bones strong and reduce the risk of osteoporosis.<\/em>[\/caption]\r\n\r\nPreventing osteoporosis includes eliminating any risk factors that can be controlled through changes of behavior. If you smoke, stop. If you drink, reduce your alcohol consumption \u2014 or cut it out altogether. Eat a nutritious diet and make sure you are getting adequate amounts of vitamin D. You should also avoid drinking carbonated beverages.\r\n\r\n \r\n\r\nIf you\u2019re a couch potato, get involved in regular exercise. Aerobic, weight-bearing, and resistance exercises can all help maintain or increase bone mineral density (for example hiking as in Figure 11.7.5). Exercise puts stress on bones, which stimulates bone building. Good weight-bearing exercises for bone building include weight training, dancing, stair climbing, running, and hiking (see Figure 11.7.5). Biking and swimming are less beneficial, because they don\u2019t stress the bones. Ideally, you should exercise for at least 30 minutes a day most days of the week.\r\n\r\n \r\nOsteoarthritis<\/span><\/div>\r\n \r\n\r\n[caption id=\"attachment_4129\" align=\"alignleft\" width=\"161\"] Figure 11.7.6 The areas shaded in blue indicate the joints most commonly affected by OA.<\/em>[\/caption]\r\n\r\n[pb_glossary id=\"4102\"]Osteoarthritis[\/pb_glossary] (OA<\/a>)<\/strong> is a joint disease that results from the breakdown of joint cartilage and bone. The most common symptoms are joint pain and stiffness. Other symptoms may include joint swelling and decreased range of motion. Initially, symptoms may occur only after exercise or prolonged activity, but over time, they may become constant, negatively affecting work and normal daily activities. As shown in Figure 11.7.6, the most commonly involved joints are those near the ends of the fingers, at the bases of the thumbs, and in the neck, lower back, hips, and knees. Often, joints on one side of the body are affected more than those on the other side.\r\n\r\n \r\nWhat Causes Osteoarthritis?<\/h2>\r\nOA is thought to be caused by mechanical stress on the\u00a0joints\u00a0with insufficient self-repair of cartilage. The stress may be exacerbated by low-grade inflammation of the joints, as\u00a0cells\u00a0lining the joint attempt to remove breakdown products from cartilage in the synovial space. OA develops over decades as stress and inflammation cause increasing loss of articular cartilage. Eventually, bones may have no cartilage to separate them, so bones rub against one another at joints. This damages the articular surfaces of the bones and contributes to the pain and other symptoms of OA. Because of the pain, movement may be curtailed, leading to loss of muscle, as well.\r\nDiagnosing Osteoarthritis<\/h2>\r\n[caption id=\"attachment_4131\" align=\"alignright\" width=\"300\"] Figure 11.7.7 A bunion is a common sign of osteoarthritis. It is typically located at the base of the big toe.<\/em>[\/caption]\r\n\r\nDiagnosis of OA is typically made on the basis of signs and symptoms. Signs include joint deformities, such as bony nodules on the finger joints or bunions on the feet (as illustrated in Figure 11.7.7). Symptoms include joint pain and stiffness. The pain is usually described as a sharp ache or burning sensation, which may be in the muscles and tendons around the affected joints, as well as in the joints themselves. The pain is usually made worse by prolonged activity, and it typically improves with rest. Stiffness is most common when first arising in the morning, and it usually improves quickly as daily activities are undertaken.\r\n\r\nX-rays\u00a0or other tests are sometimes used to either support the diagnosis of OA or to rule out other disorders.\u00a0Blood tests might be done, for example, to look for factors that indicate rheumatoid arthritis (RA), an\u00a0autoimmune disease\u00a0in which the immune system attacks the body\u2019s joints. If these factors are not present in the\u00a0blood, then RA is unlikely, and a diagnosis of OA is more likely to be correct.\r\nRisk Factors for Osteoarthritis<\/h2>\r\nAge is the chief risk factor for osteoarthritis. By age 65, as many as 80 per cent of all people have evidence of osteoarthritis. However, people are more likely to develop OA \u2014 especially at younger ages \u2014 if they have had a joint injury. A high school football player might have a bad knee injury that damages the joint, leading to OA in the knee by the time he is in his thirties. If people have joints that are misaligned due to congenital malformations or disease, they are also more likely to develop OA. Excess body weight is another factor that increases the risk of OA, because of the added stress it places on weight-bearing joints.\r\n\r\nResearchers have found that people with a family history of OA have a heightened risk of developing the disorder, which suggests that genetic factors are also involved in OA. It is likely that many different genes are needed for normal cartilage and cartilage repair. If such genes are defective and cartilage is abnormal or not normally repaired, OA is more likely to result.\r\nTreatment and Prevention of Osteoarthritis<\/h2>\r\nOA cannot be cured, but the symptoms \u2014 especially the pain \u2014 can often be treated successfully to maintain good quality of life for people with OA. Treatments include exercise, efforts to decrease stress on joints, pain medications, and surgery.\r\nExercise<\/h3>\r\nExercise helps maintain joint mobility and also increases muscle strength. Stronger muscles may help keep the bones in joints correctly aligned, and this can reduce joint stress. Good exercises for OA include swimming, water aerobics (see Figure 11.7.8 below), and biking. These activities are recommended for OA, because they put relatively little stress on the joints.\r\n\r\n[caption id=\"attachment_4133\" align=\"aligncenter\" width=\"1000\"] Figure 11.7.8 Exercising in water provides buoyancy that places less stress on joints than the same exercises would on the ground or other hard surface.<\/em>[\/caption]\r\n\r\n\r\n\r\nExercising in water provides buoyancy that places less stress on joints than the same exercises would on the ground or other hard surface.\r\n\r\n<\/div>\r\nDe-stressing Joints<\/h3>\r\nEfforts to decrease stress on joints include resting and using mobility devices such as canes, which reduce the\u00a0weight\u00a0placed on weight-bearing joints and also improve stability. In people who are overweight, losing weight may also reduce joint stress.\r\nPain Medications<\/h3>\r\nThe first type of pain medication likely to be prescribed for OA is acetaminophen (e.g., Tylenol). When taken as prescribed, it has a relatively low risk of serious side effects. If this medication is inadequate to relieve the pain, non-steroidal anti-inflammatory drugs (NSAIDs, such as ibuprofen) may be prescribed. NSAIDs, however, are more likely to cause serious side effects, such as gastrointestinal bleeding, elevated\u00a0blood pressure, and increased risk of stroke. Opioids usually are reserved for patients who have suffered serious side effects or for whom other medications have failed to relieve pain. Due to the risk of [pb_glossary id=\"3184\"]addiction[\/pb_glossary], only short-term use of opioids is generally recommended.\r\nSurgery<\/h3>\r\nJoint-replacement surgery is the most common treatment for serious OA in the knee or hip. In fact, knee and hip replacement surgeries are among the most common of all surgeries. Although they require a long period of healing and physical rehabilitation, the results are usually worth it. The replacement \u201cparts\u201d are usually pain-free and fully functional for at least a couple of decades. Quality, durability, and customization of artificial joints are constantly improving.\r\n\r\nTry out this neat Virtual Hip Resurfacing<\/a> activity by Edheads (you will need to enable Flash).\r\n\r\nFeature: Myth vs. Reality<\/span>\r\n\r\nAbout one out of every 5 adults in Canada suffer from\u00a0 osteoarthritis. The more you know about this disease, the more you can do to avoid it or slow its progression. That means knowing the facts, rather than believing the myths about osteoarthritis.\r\n
Risk Factors for Osteoporosis<\/h2>\r\nThere are a number of factors that increase the risk of osteoporosis. Eleven of them are listed below. The first five factors cannot be controlled, but the remaining factors generally can be controlled by changing behaviors.\r\n\r\n \t- Older age<\/li>\r\n \t
- Female sex<\/li>\r\n \t
- European or Asian ancestry<\/li>\r\n \t
- Family history of osteoporosis<\/li>\r\n \t
- Short stature and small bones<\/li>\r\n \t
- Smoking<\/li>\r\n \t
- Alcohol consumption<\/li>\r\n \t
- Lack of exercise<\/li>\r\n \t
- Vitamin D deficiency<\/li>\r\n \t
- Poor nutrition<\/li>\r\n \t
- Consumption of soft drinks<\/li>\r\n<\/ol>\r\n
Treatment and Prevention of Osteoporosis<\/h2>\r\nOsteoporosis is often treated with medications that may slow or even reverse bone loss. Medications called bisphosphonates, for example, are commonly prescribed.\u00a0Bisphosphonates slow down the breakdown of bone,\u00a0allowing\u00a0bone rebuilding during remodeling\u00a0to\u00a0keep pace. This helps maintain bone density and decreases the risk of fractures.\u00a0The medications may be more effective in patients who have already broken bones than in those who have not, significantly reducing their risk of another fracture. Generally, patients are not recommended to stay on bisphosphonates for more than three or four years. There is no evidence for continued benefit after this time \u2014 in fact, there is a potential for adverse side effects.\r\n\r\n[caption id=\"attachment_4128\" align=\"alignright\" width=\"491\"] Figure 11.7.5 Hiking is an enjoyable way to help keep bones strong and reduce the risk of osteoporosis.<\/em>[\/caption]\r\n\r\nPreventing osteoporosis includes eliminating any risk factors that can be controlled through changes of behavior. If you smoke, stop. If you drink, reduce your alcohol consumption \u2014 or cut it out altogether. Eat a nutritious diet and make sure you are getting adequate amounts of vitamin D. You should also avoid drinking carbonated beverages.\r\n\r\n \r\n\r\nIf you\u2019re a couch potato, get involved in regular exercise. Aerobic, weight-bearing, and resistance exercises can all help maintain or increase bone mineral density (for example hiking as in Figure 11.7.5). Exercise puts stress on bones, which stimulates bone building. Good weight-bearing exercises for bone building include weight training, dancing, stair climbing, running, and hiking (see Figure 11.7.5). Biking and swimming are less beneficial, because they don\u2019t stress the bones. Ideally, you should exercise for at least 30 minutes a day most days of the week.\r\n\r\n \r\nOsteoarthritis<\/span><\/div>\r\n \r\n\r\n[caption id=\"attachment_4129\" align=\"alignleft\" width=\"161\"] Figure 11.7.6 The areas shaded in blue indicate the joints most commonly affected by OA.<\/em>[\/caption]\r\n\r\n[pb_glossary id=\"4102\"]Osteoarthritis[\/pb_glossary] (OA<\/a>)<\/strong> is a joint disease that results from the breakdown of joint cartilage and bone. The most common symptoms are joint pain and stiffness. Other symptoms may include joint swelling and decreased range of motion. Initially, symptoms may occur only after exercise or prolonged activity, but over time, they may become constant, negatively affecting work and normal daily activities. As shown in Figure 11.7.6, the most commonly involved joints are those near the ends of the fingers, at the bases of the thumbs, and in the neck, lower back, hips, and knees. Often, joints on one side of the body are affected more than those on the other side.\r\n\r\n \r\nWhat Causes Osteoarthritis?<\/h2>\r\nOA is thought to be caused by mechanical stress on the\u00a0joints\u00a0with insufficient self-repair of cartilage. The stress may be exacerbated by low-grade inflammation of the joints, as\u00a0cells\u00a0lining the joint attempt to remove breakdown products from cartilage in the synovial space. OA develops over decades as stress and inflammation cause increasing loss of articular cartilage. Eventually, bones may have no cartilage to separate them, so bones rub against one another at joints. This damages the articular surfaces of the bones and contributes to the pain and other symptoms of OA. Because of the pain, movement may be curtailed, leading to loss of muscle, as well.\r\nDiagnosing Osteoarthritis<\/h2>\r\n[caption id=\"attachment_4131\" align=\"alignright\" width=\"300\"] Figure 11.7.7 A bunion is a common sign of osteoarthritis. It is typically located at the base of the big toe.<\/em>[\/caption]\r\n\r\nDiagnosis of OA is typically made on the basis of signs and symptoms. Signs include joint deformities, such as bony nodules on the finger joints or bunions on the feet (as illustrated in Figure 11.7.7). Symptoms include joint pain and stiffness. The pain is usually described as a sharp ache or burning sensation, which may be in the muscles and tendons around the affected joints, as well as in the joints themselves. The pain is usually made worse by prolonged activity, and it typically improves with rest. Stiffness is most common when first arising in the morning, and it usually improves quickly as daily activities are undertaken.\r\n\r\nX-rays\u00a0or other tests are sometimes used to either support the diagnosis of OA or to rule out other disorders.\u00a0Blood tests might be done, for example, to look for factors that indicate rheumatoid arthritis (RA), an\u00a0autoimmune disease\u00a0in which the immune system attacks the body\u2019s joints. If these factors are not present in the\u00a0blood, then RA is unlikely, and a diagnosis of OA is more likely to be correct.\r\nRisk Factors for Osteoarthritis<\/h2>\r\nAge is the chief risk factor for osteoarthritis. By age 65, as many as 80 per cent of all people have evidence of osteoarthritis. However, people are more likely to develop OA \u2014 especially at younger ages \u2014 if they have had a joint injury. A high school football player might have a bad knee injury that damages the joint, leading to OA in the knee by the time he is in his thirties. If people have joints that are misaligned due to congenital malformations or disease, they are also more likely to develop OA. Excess body weight is another factor that increases the risk of OA, because of the added stress it places on weight-bearing joints.\r\n\r\nResearchers have found that people with a family history of OA have a heightened risk of developing the disorder, which suggests that genetic factors are also involved in OA. It is likely that many different genes are needed for normal cartilage and cartilage repair. If such genes are defective and cartilage is abnormal or not normally repaired, OA is more likely to result.\r\nTreatment and Prevention of Osteoarthritis<\/h2>\r\nOA cannot be cured, but the symptoms \u2014 especially the pain \u2014 can often be treated successfully to maintain good quality of life for people with OA. Treatments include exercise, efforts to decrease stress on joints, pain medications, and surgery.\r\nExercise<\/h3>\r\nExercise helps maintain joint mobility and also increases muscle strength. Stronger muscles may help keep the bones in joints correctly aligned, and this can reduce joint stress. Good exercises for OA include swimming, water aerobics (see Figure 11.7.8 below), and biking. These activities are recommended for OA, because they put relatively little stress on the joints.\r\n\r\n[caption id=\"attachment_4133\" align=\"aligncenter\" width=\"1000\"] Figure 11.7.8 Exercising in water provides buoyancy that places less stress on joints than the same exercises would on the ground or other hard surface.<\/em>[\/caption]\r\n\r\n\r\n\r\nExercising in water provides buoyancy that places less stress on joints than the same exercises would on the ground or other hard surface.\r\n\r\n<\/div>\r\nDe-stressing Joints<\/h3>\r\nEfforts to decrease stress on joints include resting and using mobility devices such as canes, which reduce the\u00a0weight\u00a0placed on weight-bearing joints and also improve stability. In people who are overweight, losing weight may also reduce joint stress.\r\nPain Medications<\/h3>\r\nThe first type of pain medication likely to be prescribed for OA is acetaminophen (e.g., Tylenol). When taken as prescribed, it has a relatively low risk of serious side effects. If this medication is inadequate to relieve the pain, non-steroidal anti-inflammatory drugs (NSAIDs, such as ibuprofen) may be prescribed. NSAIDs, however, are more likely to cause serious side effects, such as gastrointestinal bleeding, elevated\u00a0blood pressure, and increased risk of stroke. Opioids usually are reserved for patients who have suffered serious side effects or for whom other medications have failed to relieve pain. Due to the risk of [pb_glossary id=\"3184\"]addiction[\/pb_glossary], only short-term use of opioids is generally recommended.\r\nSurgery<\/h3>\r\nJoint-replacement surgery is the most common treatment for serious OA in the knee or hip. In fact, knee and hip replacement surgeries are among the most common of all surgeries. Although they require a long period of healing and physical rehabilitation, the results are usually worth it. The replacement \u201cparts\u201d are usually pain-free and fully functional for at least a couple of decades. Quality, durability, and customization of artificial joints are constantly improving.\r\n\r\nTry out this neat Virtual Hip Resurfacing<\/a> activity by Edheads (you will need to enable Flash).\r\n\r\nFeature: Myth vs. Reality<\/span>\r\n\r\nAbout one out of every 5 adults in Canada suffer from\u00a0 osteoarthritis. The more you know about this disease, the more you can do to avoid it or slow its progression. That means knowing the facts, rather than believing the myths about osteoarthritis.\r\n
Treatment and Prevention of Osteoporosis<\/h2>\r\nOsteoporosis is often treated with medications that may slow or even reverse bone loss. Medications called bisphosphonates, for example, are commonly prescribed.\u00a0Bisphosphonates slow down the breakdown of bone,\u00a0allowing\u00a0bone rebuilding during remodeling\u00a0to\u00a0keep pace. This helps maintain bone density and decreases the risk of fractures.\u00a0The medications may be more effective in patients who have already broken bones than in those who have not, significantly reducing their risk of another fracture. Generally, patients are not recommended to stay on bisphosphonates for more than three or four years. There is no evidence for continued benefit after this time \u2014 in fact, there is a potential for adverse side effects.\r\n\r\n[caption id=\"attachment_4128\" align=\"alignright\" width=\"491\"] Figure 11.7.5 Hiking is an enjoyable way to help keep bones strong and reduce the risk of osteoporosis.<\/em>[\/caption]\r\n\r\nPreventing osteoporosis includes eliminating any risk factors that can be controlled through changes of behavior. If you smoke, stop. If you drink, reduce your alcohol consumption \u2014 or cut it out altogether. Eat a nutritious diet and make sure you are getting adequate amounts of vitamin D. You should also avoid drinking carbonated beverages.\r\n\r\n \r\n\r\nIf you\u2019re a couch potato, get involved in regular exercise. Aerobic, weight-bearing, and resistance exercises can all help maintain or increase bone mineral density (for example hiking as in Figure 11.7.5). Exercise puts stress on bones, which stimulates bone building. Good weight-bearing exercises for bone building include weight training, dancing, stair climbing, running, and hiking (see Figure 11.7.5). Biking and swimming are less beneficial, because they don\u2019t stress the bones. Ideally, you should exercise for at least 30 minutes a day most days of the week.\r\n\r\n \r\nOsteoarthritis<\/span><\/div>\r\n \r\n\r\n[caption id=\"attachment_4129\" align=\"alignleft\" width=\"161\"] Figure 11.7.6 The areas shaded in blue indicate the joints most commonly affected by OA.<\/em>[\/caption]\r\n\r\n[pb_glossary id=\"4102\"]Osteoarthritis[\/pb_glossary] (OA<\/a>)<\/strong> is a joint disease that results from the breakdown of joint cartilage and bone. The most common symptoms are joint pain and stiffness. Other symptoms may include joint swelling and decreased range of motion. Initially, symptoms may occur only after exercise or prolonged activity, but over time, they may become constant, negatively affecting work and normal daily activities. As shown in Figure 11.7.6, the most commonly involved joints are those near the ends of the fingers, at the bases of the thumbs, and in the neck, lower back, hips, and knees. Often, joints on one side of the body are affected more than those on the other side.\r\n\r\n \r\nWhat Causes Osteoarthritis?<\/h2>\r\nOA is thought to be caused by mechanical stress on the\u00a0joints\u00a0with insufficient self-repair of cartilage. The stress may be exacerbated by low-grade inflammation of the joints, as\u00a0cells\u00a0lining the joint attempt to remove breakdown products from cartilage in the synovial space. OA develops over decades as stress and inflammation cause increasing loss of articular cartilage. Eventually, bones may have no cartilage to separate them, so bones rub against one another at joints. This damages the articular surfaces of the bones and contributes to the pain and other symptoms of OA. Because of the pain, movement may be curtailed, leading to loss of muscle, as well.\r\nDiagnosing Osteoarthritis<\/h2>\r\n[caption id=\"attachment_4131\" align=\"alignright\" width=\"300\"] Figure 11.7.7 A bunion is a common sign of osteoarthritis. It is typically located at the base of the big toe.<\/em>[\/caption]\r\n\r\nDiagnosis of OA is typically made on the basis of signs and symptoms. Signs include joint deformities, such as bony nodules on the finger joints or bunions on the feet (as illustrated in Figure 11.7.7). Symptoms include joint pain and stiffness. The pain is usually described as a sharp ache or burning sensation, which may be in the muscles and tendons around the affected joints, as well as in the joints themselves. The pain is usually made worse by prolonged activity, and it typically improves with rest. Stiffness is most common when first arising in the morning, and it usually improves quickly as daily activities are undertaken.\r\n\r\nX-rays\u00a0or other tests are sometimes used to either support the diagnosis of OA or to rule out other disorders.\u00a0Blood tests might be done, for example, to look for factors that indicate rheumatoid arthritis (RA), an\u00a0autoimmune disease\u00a0in which the immune system attacks the body\u2019s joints. If these factors are not present in the\u00a0blood, then RA is unlikely, and a diagnosis of OA is more likely to be correct.\r\nRisk Factors for Osteoarthritis<\/h2>\r\nAge is the chief risk factor for osteoarthritis. By age 65, as many as 80 per cent of all people have evidence of osteoarthritis. However, people are more likely to develop OA \u2014 especially at younger ages \u2014 if they have had a joint injury. A high school football player might have a bad knee injury that damages the joint, leading to OA in the knee by the time he is in his thirties. If people have joints that are misaligned due to congenital malformations or disease, they are also more likely to develop OA. Excess body weight is another factor that increases the risk of OA, because of the added stress it places on weight-bearing joints.\r\n\r\nResearchers have found that people with a family history of OA have a heightened risk of developing the disorder, which suggests that genetic factors are also involved in OA. It is likely that many different genes are needed for normal cartilage and cartilage repair. If such genes are defective and cartilage is abnormal or not normally repaired, OA is more likely to result.\r\nTreatment and Prevention of Osteoarthritis<\/h2>\r\nOA cannot be cured, but the symptoms \u2014 especially the pain \u2014 can often be treated successfully to maintain good quality of life for people with OA. Treatments include exercise, efforts to decrease stress on joints, pain medications, and surgery.\r\nExercise<\/h3>\r\nExercise helps maintain joint mobility and also increases muscle strength. Stronger muscles may help keep the bones in joints correctly aligned, and this can reduce joint stress. Good exercises for OA include swimming, water aerobics (see Figure 11.7.8 below), and biking. These activities are recommended for OA, because they put relatively little stress on the joints.\r\n\r\n[caption id=\"attachment_4133\" align=\"aligncenter\" width=\"1000\"] Figure 11.7.8 Exercising in water provides buoyancy that places less stress on joints than the same exercises would on the ground or other hard surface.<\/em>[\/caption]\r\n\r\n\r\n\r\nExercising in water provides buoyancy that places less stress on joints than the same exercises would on the ground or other hard surface.\r\n\r\n<\/div>\r\nDe-stressing Joints<\/h3>\r\nEfforts to decrease stress on joints include resting and using mobility devices such as canes, which reduce the\u00a0weight\u00a0placed on weight-bearing joints and also improve stability. In people who are overweight, losing weight may also reduce joint stress.\r\nPain Medications<\/h3>\r\nThe first type of pain medication likely to be prescribed for OA is acetaminophen (e.g., Tylenol). When taken as prescribed, it has a relatively low risk of serious side effects. If this medication is inadequate to relieve the pain, non-steroidal anti-inflammatory drugs (NSAIDs, such as ibuprofen) may be prescribed. NSAIDs, however, are more likely to cause serious side effects, such as gastrointestinal bleeding, elevated\u00a0blood pressure, and increased risk of stroke. Opioids usually are reserved for patients who have suffered serious side effects or for whom other medications have failed to relieve pain. Due to the risk of [pb_glossary id=\"3184\"]addiction[\/pb_glossary], only short-term use of opioids is generally recommended.\r\nSurgery<\/h3>\r\nJoint-replacement surgery is the most common treatment for serious OA in the knee or hip. In fact, knee and hip replacement surgeries are among the most common of all surgeries. Although they require a long period of healing and physical rehabilitation, the results are usually worth it. The replacement \u201cparts\u201d are usually pain-free and fully functional for at least a couple of decades. Quality, durability, and customization of artificial joints are constantly improving.\r\n\r\nTry out this neat Virtual Hip Resurfacing<\/a> activity by Edheads (you will need to enable Flash).\r\n\r\nFeature: Myth vs. Reality<\/span>\r\n\r\nAbout one out of every 5 adults in Canada suffer from\u00a0 osteoarthritis. The more you know about this disease, the more you can do to avoid it or slow its progression. That means knowing the facts, rather than believing the myths about osteoarthritis.\r\n
Figure 11.7.6 The areas shaded in blue indicate the joints most commonly affected by OA.<\/em>[\/caption]\r\n\r\n[pb_glossary id=\"4102\"]Osteoarthritis[\/pb_glossary] (OA<\/a>)<\/strong> is a joint disease that results from the breakdown of joint cartilage and bone. The most common symptoms are joint pain and stiffness. Other symptoms may include joint swelling and decreased range of motion. Initially, symptoms may occur only after exercise or prolonged activity, but over time, they may become constant, negatively affecting work and normal daily activities. As shown in Figure 11.7.6, the most commonly involved joints are those near the ends of the fingers, at the bases of the thumbs, and in the neck, lower back, hips, and knees. Often, joints on one side of the body are affected more than those on the other side.\r\n\r\n \r\nWhat Causes Osteoarthritis?<\/h2>\r\nOA is thought to be caused by mechanical stress on the\u00a0joints\u00a0with insufficient self-repair of cartilage. The stress may be exacerbated by low-grade inflammation of the joints, as\u00a0cells\u00a0lining the joint attempt to remove breakdown products from cartilage in the synovial space. OA develops over decades as stress and inflammation cause increasing loss of articular cartilage. Eventually, bones may have no cartilage to separate them, so bones rub against one another at joints. This damages the articular surfaces of the bones and contributes to the pain and other symptoms of OA. Because of the pain, movement may be curtailed, leading to loss of muscle, as well.\r\nDiagnosing Osteoarthritis<\/h2>\r\n[caption id=\"attachment_4131\" align=\"alignright\" width=\"300\"] Figure 11.7.7 A bunion is a common sign of osteoarthritis. It is typically located at the base of the big toe.<\/em>[\/caption]\r\n\r\nDiagnosis of OA is typically made on the basis of signs and symptoms. Signs include joint deformities, such as bony nodules on the finger joints or bunions on the feet (as illustrated in Figure 11.7.7). Symptoms include joint pain and stiffness. The pain is usually described as a sharp ache or burning sensation, which may be in the muscles and tendons around the affected joints, as well as in the joints themselves. The pain is usually made worse by prolonged activity, and it typically improves with rest. Stiffness is most common when first arising in the morning, and it usually improves quickly as daily activities are undertaken.\r\n\r\nX-rays\u00a0or other tests are sometimes used to either support the diagnosis of OA or to rule out other disorders.\u00a0Blood tests might be done, for example, to look for factors that indicate rheumatoid arthritis (RA), an\u00a0autoimmune disease\u00a0in which the immune system attacks the body\u2019s joints. If these factors are not present in the\u00a0blood, then RA is unlikely, and a diagnosis of OA is more likely to be correct.\r\nRisk Factors for Osteoarthritis<\/h2>\r\nAge is the chief risk factor for osteoarthritis. By age 65, as many as 80 per cent of all people have evidence of osteoarthritis. However, people are more likely to develop OA \u2014 especially at younger ages \u2014 if they have had a joint injury. A high school football player might have a bad knee injury that damages the joint, leading to OA in the knee by the time he is in his thirties. If people have joints that are misaligned due to congenital malformations or disease, they are also more likely to develop OA. Excess body weight is another factor that increases the risk of OA, because of the added stress it places on weight-bearing joints.\r\n\r\nResearchers have found that people with a family history of OA have a heightened risk of developing the disorder, which suggests that genetic factors are also involved in OA. It is likely that many different genes are needed for normal cartilage and cartilage repair. If such genes are defective and cartilage is abnormal or not normally repaired, OA is more likely to result.\r\nTreatment and Prevention of Osteoarthritis<\/h2>\r\nOA cannot be cured, but the symptoms \u2014 especially the pain \u2014 can often be treated successfully to maintain good quality of life for people with OA. Treatments include exercise, efforts to decrease stress on joints, pain medications, and surgery.\r\nExercise<\/h3>\r\nExercise helps maintain joint mobility and also increases muscle strength. Stronger muscles may help keep the bones in joints correctly aligned, and this can reduce joint stress. Good exercises for OA include swimming, water aerobics (see Figure 11.7.8 below), and biking. These activities are recommended for OA, because they put relatively little stress on the joints.\r\n\r\n[caption id=\"attachment_4133\" align=\"aligncenter\" width=\"1000\"] Figure 11.7.8 Exercising in water provides buoyancy that places less stress on joints than the same exercises would on the ground or other hard surface.<\/em>[\/caption]\r\n\r\n\r\n\r\nExercising in water provides buoyancy that places less stress on joints than the same exercises would on the ground or other hard surface.\r\n\r\n<\/div>\r\nDe-stressing Joints<\/h3>\r\nEfforts to decrease stress on joints include resting and using mobility devices such as canes, which reduce the\u00a0weight\u00a0placed on weight-bearing joints and also improve stability. In people who are overweight, losing weight may also reduce joint stress.\r\nPain Medications<\/h3>\r\nThe first type of pain medication likely to be prescribed for OA is acetaminophen (e.g., Tylenol). When taken as prescribed, it has a relatively low risk of serious side effects. If this medication is inadequate to relieve the pain, non-steroidal anti-inflammatory drugs (NSAIDs, such as ibuprofen) may be prescribed. NSAIDs, however, are more likely to cause serious side effects, such as gastrointestinal bleeding, elevated\u00a0blood pressure, and increased risk of stroke. Opioids usually are reserved for patients who have suffered serious side effects or for whom other medications have failed to relieve pain. Due to the risk of [pb_glossary id=\"3184\"]addiction[\/pb_glossary], only short-term use of opioids is generally recommended.\r\nSurgery<\/h3>\r\nJoint-replacement surgery is the most common treatment for serious OA in the knee or hip. In fact, knee and hip replacement surgeries are among the most common of all surgeries. Although they require a long period of healing and physical rehabilitation, the results are usually worth it. The replacement \u201cparts\u201d are usually pain-free and fully functional for at least a couple of decades. Quality, durability, and customization of artificial joints are constantly improving.\r\n\r\nTry out this neat Virtual Hip Resurfacing<\/a> activity by Edheads (you will need to enable Flash).\r\n\r\nFeature: Myth vs. Reality<\/span>\r\n\r\nAbout one out of every 5 adults in Canada suffer from\u00a0 osteoarthritis. The more you know about this disease, the more you can do to avoid it or slow its progression. That means knowing the facts, rather than believing the myths about osteoarthritis.\r\n
Figure 11.7.7 A bunion is a common sign of osteoarthritis. It is typically located at the base of the big toe.<\/em>[\/caption]\r\n\r\nDiagnosis of OA is typically made on the basis of signs and symptoms. Signs include joint deformities, such as bony nodules on the finger joints or bunions on the feet (as illustrated in Figure 11.7.7). Symptoms include joint pain and stiffness. The pain is usually described as a sharp ache or burning sensation, which may be in the muscles and tendons around the affected joints, as well as in the joints themselves. The pain is usually made worse by prolonged activity, and it typically improves with rest. Stiffness is most common when first arising in the morning, and it usually improves quickly as daily activities are undertaken.\r\n\r\nX-rays\u00a0or other tests are sometimes used to either support the diagnosis of OA or to rule out other disorders.\u00a0Blood tests might be done, for example, to look for factors that indicate rheumatoid arthritis (RA), an\u00a0autoimmune disease\u00a0in which the immune system attacks the body\u2019s joints. If these factors are not present in the\u00a0blood, then RA is unlikely, and a diagnosis of OA is more likely to be correct.\r\n![Blausen_0686_Osteoporosis_01<\/a> by](\"https:\/\/commons.wikimedia.org\/wiki\/File:Blausen_0686_Osteoporosis_01.png\"){kind=link}
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