Osteoporosis Osteoporosis By By

Dr. Khattab OmarDr. Khattab Omar

Prof. & Head of Obstetrics and Prof. & Head of Obstetrics and Gynaecology Department Gynaecology Department

Faculty of Medicine, Al-Azhar Faculty of Medicine, Al-Azhar University, DamiettaUniversity, Damietta

Physiology:Physiology:

Bone mineral density (BMD) of Bone mineral density (BMD) of the lumbar vertebrae is more the lumbar vertebrae is more than double that of the femur than double that of the femur

neck & distal radius. neck & distal radius.

Trabecular bones are more Trabecular bones are more sensitive to the loss of estrogsensitive to the loss of estrog

Skeletal maturity in females Skeletal maturity in females peaks at the age of 30-35. peaks at the age of 30-35.

Definitions:Definitions:

WHO T-score for decreased bone WHO T-score for decreased bone density is the number of SD relative density is the number of SD relative to peak bone mass of healthy to peak bone mass of healthy women aged 30. women aged 30.

Osteopenia:Osteopenia: T = 1-2.5 SD <young normal T = 1-2.5 SD <young normal mean. mean.

Osteoporosis: T >2.5 SD <young normal Osteoporosis: T >2.5 SD <young normal mean or -1 to -2.5 SD associated with mean or -1 to -2.5 SD associated with fracture.fracture.

Osteoporotic bone is not calcium-deficient. Osteoporotic bone is not calcium-deficient.

FractureFracture thresholdthreshold is reached is reached at around the age of 58. at around the age of 58. Median age of fracture hip in Median age of fracture hip in females is 80. females is 80.

1 SD decrease in femoral neck 1 SD decrease in femoral neck bone bone densitydensity increases the increases the risk of hip fracture by 2.6-x.risk of hip fracture by 2.6-x.

Prevalence: Osteoporosis is very highly prevalent in the industrialized countries mainly due to the high life expectancy. Black Africans develop a higher peak bone mass. The high incidence of lactose intolerance in the Chinese and Japanese may increase their risk of osteoporosis. The increase in postmenopausal osteoporosis (±30%) is attributed partly to improvements in diagnostic methods & partly to increased awareness of the disease. However, only 20-30% of the patients are diagnosed and treated. Prevalence is 6% in men of the same age group (≥1:5). Male : female hip fracture in the elderly is 1:3.This may be due to the lower life expectancy, the higher peak bone mass & the absence of an equivalent to menopause in men. By age 75, nearly half of women have suffered vertebral fractures.

Pathophysiology:Pathophysiology: Osteoporosis occurs Osteoporosis occurs after a long latent period due to loss of after a long latent period due to loss of the honey-comb micro-architecture of the honey-comb micro-architecture of bone which is responsible for shock bone which is responsible for shock absorption. absorption.

Aetiology: Aetiology: - Early cases of 2ry Early cases of 2ry amenorr.amenorr. failure to achieve optimal peak failure to achieve optimal peak

bone mass or may bone mass or may → → progressive bone loss. PCOS, dose not progressive bone loss. PCOS, dose not cause bone loss (hyperestrogenism). cause bone loss (hyperestrogenism).

- SportsSports maintain or increase bone substance. However, maintain or increase bone substance. However, hormonal changes (amenorr. & estrogen deficiency) induced hormonal changes (amenorr. & estrogen deficiency) induced by high competition sports dominate. Also, BMD decreases by high competition sports dominate. Also, BMD decreases again very rapidly after the training is stopped. The same for again very rapidly after the training is stopped. The same for ballet dancers. ballet dancers.

- - MiscellaneousMiscellaneous: low body wt, family history, sedentary life-style, : low body wt, family history, sedentary life-style, thyrotoxicosis, anticonvulsant therapy, long term use of thyrotoxicosis, anticonvulsant therapy, long term use of corticosteroids & heparin & COAD. Smoking reduces corticosteroids & heparin & COAD. Smoking reduces production of estrogen, blocks estrogen receptors & production of estrogen, blocks estrogen receptors & facilitates conversion of Efacilitates conversion of E22 to E to E11

- Excessive coffee drinking is a risk factor 2ry to diuresis. Excessive coffee drinking is a risk factor 2ry to diuresis.

- Cola drinks contain high phosphate content. Cola drinks contain high phosphate content. - Alcohol is diuretic; intake is associated with malnutrition Alcohol is diuretic; intake is associated with malnutrition

smoking, little activity, reduced absorption of vit D & Ca smoking, little activity, reduced absorption of vit D & Ca due to cirrhosis & direct inhibition of osteoblasts. due to cirrhosis & direct inhibition of osteoblasts.

- DM is a moderate risk factor. Intermittent - DM is a moderate risk factor. Intermittent acidosis may lead to Ca mobilization. acidosis may lead to Ca mobilization. Development of nephropathy leads to Development of nephropathy leads to renal bone disease (for prevention & ttt: renal bone disease (for prevention & ttt: the most important measure is to lower the most important measure is to lower serum P by intake of Ca carbonate).serum P by intake of Ca carbonate).

Clinical featuresClinical features- Asymptomatic. Asymptomatic. - Chronic back pain due to changes in Chronic back pain due to changes in

stature. This pain is not an osseous but stature. This pain is not an osseous but mainly a soft tissue &/or articular pain. mainly a soft tissue &/or articular pain.

- Pain at other skeletal sites only occurs Pain at other skeletal sites only occurs together with fracture. Acute pain of together with fracture. Acute pain of thoracic vertebral fracture should be thoracic vertebral fracture should be differentiated from myocardial infarction. differentiated from myocardial infarction.

- Low trauma fracture. - Low trauma fracture. - Vertebral fractures lead to loss of height, - Vertebral fractures lead to loss of height,

progressive deformity of the trunk, progressive deformity of the trunk, limitation of independence, depression limitation of independence, depression and social isolation. and social isolation.

InvestigationsInvestigations Bone density studies detect already-Bone density studies detect already-

existing osteoporosis. existing osteoporosis.

Up to now no sufficiently sensitive test. Up to now no sufficiently sensitive test.

BMD measurement is the most relevant and BMD measurement is the most relevant and rather low-priced screening method. rather low-priced screening method.

1- Osteoporosis is suspected with increased 1- Osteoporosis is suspected with increased radiolucency of vertebrae on X-ray films radiolucency of vertebrae on X-ray films (occurs late after loss of 30-40% of BMD). (occurs late after loss of 30-40% of BMD).

2- Densitometry monitor response to 2- Densitometry monitor response to therapy. therapy.

3- Single photon absorptiometry (densitometry) at the 3- Single photon absorptiometry (densitometry) at the calcaneous and midshaft & distal radius. calcaneous and midshaft & distal radius.

4- Dual photon absorptiometry (densitometry) at L2, 3, 4 4- Dual photon absorptiometry (densitometry) at L2, 3, 4 and femoral neck. and femoral neck.

5- Dual energy x-ray absorptiometry (DEXA; Dual energy 5- Dual energy x-ray absorptiometry (DEXA; Dual energy computed tomography) measurescomputed tomography) measures vertebralvertebral body. This body. This is is the bestthe best means of monitoring bone mass (detects a means of monitoring bone mass (detects a loss or gain of as little as 1%). loss or gain of as little as 1%). Normal bone density at Normal bone density at the lumbar spine in patients with fractures at the the lumbar spine in patients with fractures at the thoracic spine may be an indicator for non-osteoporotic thoracic spine may be an indicator for non-osteoporotic fractures. fractures.

6- Markers of bone turnover: Not routine. Markers have 6- Markers of bone turnover: Not routine. Markers have broad reference ranges. One marker of bone formation broad reference ranges. One marker of bone formation and one of resorption is sufficient. With recent fracture and one of resorption is sufficient. With recent fracture both formation and resorption occur and both types of both formation and resorption occur and both types of markers are elevated. markers are elevated. Measurement of markers may be indicated in cases Measurement of markers may be indicated in cases resistant to therapy. resistant to therapy.

RisksRisks Hip, spine and wrist fracture Hip, spine and wrist fracture

Has a 20% chance of dying. The most common Has a 20% chance of dying. The most common cause of death is thromboembolism, then cause of death is thromboembolism, then pneumonia. pneumonia.

50% lose independence. 50% lose independence.

Every year there is 60 000 hip fracture,Every year there is 60 000 hip fracture,

50 000 forearm fracture, 50 000 forearm fracture,

40 000 40 000 diagnoseddiagnosed vertebral fracture vertebral fracture

TreatmentTreatment

1- Increase calcium intake. 1- Increase calcium intake. The normal diet contains The normal diet contains 500 mg; women on ERT 500 mg; women on ERT need extra 500 mg taken need extra 500 mg taken at night, while women not at night, while women not receiving oestrogen need receiving oestrogen need extra-1000 mg. extra-1000 mg.

2- Weight-bearing exercise.2- Weight-bearing exercise.

TreatmentTreatment 3- Etidronate disodium (Didronel, 1st 3- Etidronate disodium (Didronel, 1st

generation generation bisphosphonatebisphosphonate) is much more ) is much more effective at improving lumbosacral spine effective at improving lumbosacral spine density than hip. Dose: 400 mg OD x 14 density than hip. Dose: 400 mg OD x 14 followed by Ca carbon. 0.5-1g daily for 76 followed by Ca carbon. 0.5-1g daily for 76 days (3 month cycle) for >6 months. days (3 month cycle) for >6 months. Other bisphosphonates (allendronate, Other bisphosphonates (allendronate, fosamax) is the most potent fosamax) is the most potent bisphosphonate. Dose: 5-20 mg/day for 3 bisphosphonate. Dose: 5-20 mg/day for 3 y. The patient should keep upright after y. The patient should keep upright after intake. intake.

4- 4- HRTHRT is the treatment of choice. Taken for is the treatment of choice. Taken for at least 10 years. Norethisterone at least 10 years. Norethisterone (progestogen) has a direct effect on bone (progestogen) has a direct effect on bone density. ERT reduces the incidence of density. ERT reduces the incidence of osteoporosis by osteoporosis by ≥≥50%. There is an 8% 50%. There is an 8% increase in bone density in the spine & 4% increase in bone density in the spine & 4% in the hip after only 1 y. in the hip after only 1 y.

5- Calcitonin-human 0.5 mg SQ twice/w. 5- Calcitonin-human 0.5 mg SQ twice/w.

6- Flouride (Fl) increases bone mass. 6- Flouride (Fl) increases bone mass. Flouride is monitored by alkaline Flouride is monitored by alkaline phosphatase after 1-2 months. phosphatase after 1-2 months.

7- Tibolone(Livial)maintains bone density7- Tibolone(Livial)maintains bone density

ThankThank you you