1. OSTEOPOROSIS
Dr.muthoka

2. • It is systemic skeletal disorder characterized by
decreased bone mass & deterioration of bony
microarchitecture
• the result is fragile bones & increased risk for
fractures with minimal trauma
• It is a chronic condition of multifactorial
etiology
• & is usually clinically silent til fractures occur .

3. • Osteoblasts form osteoid
• Oseoclasts resorb bone
• Bone formation is not static
• It is a system that is remodelled constantly
• Bone resorption is always followed by bone
formation a phenomena referred to as
coupling.
• The hallmark of osteoporosis is reduction in
skeletal mass caused by an imbalance btn
bone resorption & bone formation.

4. Factor influencing osteoporosis:
• Loss of gonadal function &
• Aging are the 2 most important factors
contributing to the development of this
condition.
• Lack of gonadal hormones is believed to up-
regulate osteoclast progenitor cells. Bone loss
will accelerate rapidly after menopause.

5. • Genetics
• Sex
• Race
• Medications
• Diet
• Lifestyle
• Physical activity
• &occupation

6. osteomalacia
• Osteoporosis is commonly confused with osteomalacia.
• The normal human skeleton is composed of mineral component,
ca2+hydroxyapatite(60%) & organic material mainly collagen(40%)
• In osteomalacia the bones are porous and brittle
• In osteomalacia the bones are soft
• The difference in bone consistency is related to the proportion of
mineral to organic material content.
• In osteoporosis the mineral –to collagen is within reference range
• In osteomalacia the proportion of mineral composition is reduced
relative to organic mineral content.
• Bone mineral density(BMD)in a patient is related to peak bone
mass 7 subsequent bone loss

7. CLASSIFICATION
• PRIMARY; subdivided into type 1-
postmenopausal osteoporosis & 2- senile
osteoporosis.
• SECONDARY also called type 3.

8. TYPE1; POSTMENOPAUSAL OSTEOPOROSIS
• Result from gonadal estrogen & testosterone deficiency
• Result in accelerated bone loss
• After menopause women experience an accelerated bone
loss of 1-5%per year for the first 5-7 yrs
• Estrogen deficiency cause bone to become more sensitive
to the effects of PTH; leading to an increase in ca2+ release
from bone, a decrease in ca2+ excretion & increased
production of 1,25, dihydroxyvitamin D.
• Vit Dcauses increased ca2+ absorption from the gut,
increased calcium resorption from bone & increased renal
tubular calcium re-absorption. PTH then decreases by a
negative feed back mechanism
• Cytokines: TNF ALPHA, IL1&6 influence osteoclasts.

9. TYPE2; senile osteoporosis
• Occur in women & men
• Because of decreased formation of bone and
decreased renal production of vitD occuring
late in life
• Result in loss of cortical & trabecular bone &
increased risk for fractures of hip, long bones
& vertebrae.

10. TYPE3 OSTEOPOROSIS
• An underlying dx cause osteoporosis
• Classification:
– Metabolic dx
– Connective tx dx
– Bone marrow dx
– Immobilization
– & drug use

11. CONGENITAL/GENETIC
• Osteogenesis imperfecta
• Turners syndrome
• Kleinfelter syndrome
• Hypophosphatemia
• Homocystinuria
• Mucopolysaccharidosis
• Gauchers dx
• Sickle cell anemia
• Thalassemia
• Hemophilia
ENDOCRINE
• Hyperthyroidism
• Hyperparathyroidism
• Cushings syndrome
• Acromegaly
• Estrogen deficiency
• Hypogonadism
• Diabetes mellitus
• pregnancy
DEFICIENCY STATES
• Scurvy
• Malnutrition
• Anorexia nervosa
• Protein deficiency
• Alcoholism
ORGAN FAILURE
• Liver dx
• Renal failure
MALIGNANCY
• Myeloma
• Leukemia
• Lymphoma
• Metastatic dx
DRUGS
• Heparin-induced
• Anti-convulsants: phenytoin, barbiturates,
carbamazepine-due to rx induced vit d
dericiency
• Steroid- induced
• Dilantin-induced
• Cyclosporine A
• Antacids with aluminium
Others
• Amyloidosis
• Onchronosis
• Immobility
• weightlessness