In this condition,bone density( the amount of bone tissue) is reduced because it’s deposition does not keep pace with resorption. Although the bone is adequately mineralised,it is fragile and microscopically abnormal,with loss of internal structure. Peak bone mass occurs around 35 years and then gradually declines in both sexes. Lowered oestrogen levels after menopause are associated with a period of accelerated bone loss in women. Therefore bone density in women is less then in men for given age. A range of environmental factors and diseases are also associated with decreased bone mass and are also associated with decreased porosis. Some can be influenced by changes in lifestyle. Exercise and calcium intake are important in determining eventual bone mass of an individual,and therefore the risk of osteoporosis in later life. As bone mass decreases,susceptibility to fractures increases. Immobility causes reversible osteoporosis,the extent of which corresponds to the length and degree of immobility. For instance,during prolonged periods of unconsciousness,osteoporotic changes are uniform throughout the skeleton,but immobilisation of a particular joint following fractures leads to local osteoporotic changes in involved bone only.
Common features of osteoporosis are:
- Skeletal deformity-gradual loss of height with age,causes by compression of vertebrae.
- Bone pain.
- Fractures- especially of the hip(neck of femur),wrist(colles’ fracture) and vertebrae.
