Osteoporosis is an abnormal reduction in bone tissue mass per unit volume of anatomical bone. It is characterized by decreased bone mass and increased susceptibility to fracture.
WHO operationally defines osteoporosis as bone mass density [BMD] 2.5 or more standard deviation below the mean for young adult. Ostopenia—BMD of 1 to 2.5 SD
1 out of 8 males and 1 out of 3 females in India suffer from osteoporosis.
Factors- Genetic, Hormonal, Dietary, Environmental
After 30 yrs-slow loss occurs, 0.3% in men and 0.5% in women till menopause
Menopause – till next 10 yrs- Rate of bone loss 3% ,Excessive osteoclastic activity , Loss of retraining effect of gonadal hormones
Age 65-75 yrs- Rate of loss 0.5% , Osteoclastic activity reduces .But, osteoblastic activity also reduces
Men -Phase of rapid bone loss 15-20 yrs later than women
CLASSIFICATION– Primary and Secondary
Primary osteoporosis is defined as osteoporosis that occurs in an individual who has no endocrinopathy or other disease state that would account for the changes in bone mass
ESTROGEN STATUS: stimulates osteoblasts and inhibits osteoclasts. Deficiency causes –activation of new bone remodelling sites , exaggeration of imbalance between bone formation and resorption.
ENDOCRINE DISORDERS- sex hormones , thyroid hormones , PTH , adrenal steroids
NUTRITIONAL DEFICIENCY : Ca, Vit – D, Vit-C
ALCOHOL AND SMOKING
CHRONIC ILLNESS AND TUMORS
DISUSE : absence of mechanical stress , immobilization of the limb
CLINICAL MANIFESTATIONS; Elderly people, sudden onset of pain , stooped posture, shortened stature , fractures with minimal trauma, vertebral compression fractures , acute pain in low thoracic or high lumbar region, thoracic kyphosis, loss of lumbar lordosis , decrease in axial height, appendicular fractures, proximal femoral fractures, fracture of distal femur.
VERTEBRAL COLUMN-increased radiolucency, trabecular alterations thinning, loss of trabaculae (horizontal ), Vertebral body shape alterations ,wedge shaped vertebra ,fish vertebra , pancake vertebra ,FISH VERTEBRAE, lower thoracic and lumbar vertebra , Intra-discal pressure from nucleus pulposus is more in centre in these vertebra.
MEASUREMENT OF BONE MASS
BONE MASS DENSITY (BMD)
BMD = bone mineral content (BMC) /volume of bone being studied
Several techniques are available to measure to measure density:
- Dual energy x-ray absorption (DEXA)
MANAGEMENT OF UNDERLYING DISEASE
RISK FACTOR REDUCTION: educate the patient, cessation of smoking, reduction of falls
NUTRITIONAL RECCOMENDATIONS: calcium : dairy products , green leafy veg. Ca and vit-D supplements, others: vit-K, proteins and calories.
Non-pharmacological- Calcium and vitamin-D supplementation , Fall prevention, Hip protectors , Balance and exercise programs
Pharmacological treatment- Antiresorptive Agents , Calcitonin , Hormone replacement therapy ,Selective estrogen receptor modulators , Bisphosphonates
Osteoporotic vertebral compression fractures
They present with sudden-onset back pain. For acutely symptomatic fractures, treatment with analgesics is required, including
- Nonsteroidal anti-inflammatory agents and/or acetaminophen, sometimes with the addition of a narcotic agent (codeine or oxycodone).
- Calcitonin may reduce pain related to acute vertebral compression fracture.
- Vertebroplasty or kyphoplasty percutaneous injection of artificial cement (polymethylmethacrylate) into the vertebral body.
- Short periods of bed rest may be helpful for pain management, but in general, early mobilization is recommended as it helps prevent further bone loss associated with immobilization.
- Occasionally, use of a soft elastic-style brace may facilitate earlier mobilization. Muscle spasms often occur with acute compression fractures and can be treated with muscle relaxants and heat treatments.
- Back-strengthening exercises (paraspinal) may be beneficial.
- Heat treatments help relax muscles and reduce the muscular component of discomfort. Various physical modalities, such as US and transcutaneous nerve stimulation, may be beneficial in some patients.