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Osteoporosis and Osteomalacia
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Transcript of Osteoporosis and Osteomalacia
Osteoporosis
Shoban Raj a/l Vasudayan
Osteoporosis
• Bone is qualitatively normal but there is less of it than would be expected in a person of that age and sex
• WHO: Bone mineral density that is 2.5 SD below the mean peak value in young adults of the same age and sex
• Localized ( disuse / inflammation)
• Generalize Primary Secondary
Age related Osteoporosis
• Age related changes in the bone
Osteoblastic and osteoclastic activities
Estrogen withdrawal Oophorectomy MEN – 15 yrs later
• Risk factor Family history Smoking Oophorectomy Race ( Whites, Asian
>Negroid) Chronic illness Dietary
Post menopausal Osteoporosis
Clinical features• Women age of > 55• Acute back pain• Progressive kyphosis• Fractures
Involutional osteoporosis
• > 70 years old• Involve male: female
equally• # of femoral neck • # of proximal end of
humerus• Systemic disease
Diagnosis
Height lossBody weightKyphosisHumped back
Tooth loss Wall occiput distanceRib – pelvis distance
Physical examination !! Radiography
USD mesurementDEXACT scan
Investigations
• Usually obvious • Exclude other pathology if < 45 ( full inx)• Suspect osteomalacia if:
a. Multiple #b. Increased ALPc. Looser zone on X-ray
Prevention
• Maintain adequate level of dietary calcium and vit.D
• Physical activity• Avoid smoking and alcohol • Hormonal replacement therapy (HRT)• Biphosphonates
Treatment
• Manage # - internal fixation ( early mobilization)
• Mobilization + rehab
• Treat associated factorsa. Illnessesb. Dietary deficienciesc. Sunlight exposure d. Supplementse. Biphosphonate / HRT
Secondary osteoporosis
Nutritional
Endocrine disorders
Drug induced
Malignant disease
Non Malignant disease
idiopathic
RICKETS & OSTEOMALACIA
Rickets & Osteomalacia
• Different expression of the same disease • Rickets – specifically to children ( + defective
bone growth)• Osteomalacia – Bone + softening
Incomplete mineralization of the bone !!!
Vitamin DHypophosphatemia
Calcium deficiency
Comparison
Osteomalacia• Characterized by:
a. Appearance of thin trabeculae surrounded by unusually wide uncalcified osteoid.
b. Mild cases: bone looks normal
c. Severe cases: bone cortices are thinner, signs of old/ new stress #
d. Vertebral compression # are common
Rickets• Characteristic changes arise from:
a. Inability to calcify intercellular matrix
b. Cellular part of physis is thicker than normal
c. Newly formed bone in metaphysis is weak indented and cup shaped
d. Further away from physis osteomalacia changes seen
Rickets
Vitamin D deficiency• Dietary lack
• Underexposure to sunlight
• Infant – present with tetany /convulsion, Failure to thrive, muscular flacidity
• Seldom seen nowadays
Hypophosphataemic • Impaired renal tubular
reabsorption
• Calcium levels are normal but bone mineralization is defective
• Vitamin D resistant rickets (Familial hypophosphataemic rickets)
• Commonest form today
Radiography
• Bowing of long bone – femur
• Flaring of physes• Distorted metaphyseal
margin • Cupping of metaphysis• Hazy epiphyseal margin
Looser zone
• Lucent band of decreased cortical density
• Perpendicular to bone surface
Biconcave Vertebra
• Inward protrusion of intervertebral discs
Trefoil Pelvis
• Impression of sacrum and femora into pelvis
• Also known as triradiate pelvis
Investigations
• Serum Ca and phosphate are diminished• Alkaline phosphatase is increased• Urinary calcium excretion is diminished
Treatment
VIT. D Deficiency Rickets• Corrective osteotomy• Vitamin D supplement
(calciferol 400 -1000 IU per day)
Hypophosphataemic Rickets• Large dose of vitamin D (>
50,000 IU)
• Up to 4g of inorganic phosphate a day
• Bony deformity – require bracing or osteotomy
• If the child need to be immobilized Vit. D need to be stopped temporarily
Osteomalacia
• Causes ??• Lack of vitamin D• Underexposure to
sunlight• Intestinal malabsorption• Defective conversion to
active metabolites in liver or kidney
• Why no bony changes as in rickets ????
Stress #Vertebral compression #
Radiography
• Generalized rarification of bone• Si of previous # in vertebrae, ribs, pubic rami,
long bones• Looser zone
Investigations
• Serum calcium and phosphate diminished• Alkaline phosphatase is raised• Diminished 25-HCC, 1,25-DHCC• Biopsy maybe needed• Ix for underlying cause
Treatment
• Vit D + Ca supplements• Higher dose of vit D for elderly
(2000 IU/day)• Treat underlying disorder
THANK YOU ………..