- What is the diagnosis?
This is severe osteoporosis with a compression fracture. The bone was so soft it could easily be crushed.
- Why did this disease occur in this woman?
She patient was elderly and also was inactive.
- What is the usual setting for this disease?
Osteoporosis is a big problem in the elderly, particularly women. Some factors suggested for the pathogenesis of osteoporosis include decreased skeletal mass in females, decreased estrogens or androgens, reduced physical activity, and decreased calcium intake, but none of these factors offers a complete answer. Osteoporosis from weightlessness is a deterrent to prolonged space travel. Osteoporosis, which is reduction in bone mass, must be distinguished from rickets in children and osteomalacia in adults which are due to failure of bone mineralization with increased osteoid seams in the bone.
- How does this disease differ from those caused by vitamin D deficiency or scurvy?
Vitamin D deficiency in children produces rickets. In rickets, the growing bone is not properly ossified and is weakened, leading to significant deformity. In adults, vitamin D deficiency leads to osteomalacia, which appears similar to osteoporosis because there is osteopenia (decreased bone mass).
- What therapy is available for this disease?
Persons with osteoporosis may benefit from an improved diet, including supplementation with vitamin D and calcium, and moderate exercise to help slow further bone loss.
Most drug therapies work by decreasing bone resorbtion. At any given time, there is bone that has been resorbed but not replaced, and this accounts for about 5 to 10% of bone mass. By decreasing resorbtion of bone, a gain in bone density of 5 to 10% is possible, taking about 2 to 3 years. However, no drug therapy will restore bone mass to normal. Women past menopause with accelerated bone loss may benefit from hormonal therapy using estrogen with progesterone. The estrogen retards bone resorption and thus diminishes bone loss. This effect is most prominent in the first years after menopause.
One of the more common non-estrogen therapies is the use of biphosphonates such as alendronate or risedronate that act an an inhibitor of osteoclastic activity. Biphosphonates may be beneficial, particularly in women who cannot tolerate estrogen therapy. Biphosphonates are effective in inhibiting bone loss after menopause. In one study risedronate has shown effectiveness in reducing the risk of hip fracture among elderly women with osteoporosis.
Raloxifene is a selective estrogen receptor modulator (SERM) that may also replace estrogen therapy. Raloxifene can act in concert with estrogen in bone to inhibit resorbtion and decrease the risk for fractures. Though raloxifene inhibits bone resorbtion, it does not have an anabolic effect. Additional potential benefits from raloxifene therapy include decreased risk for breast cancer, because raloxifene acts antagonistically to estrogen on the uterus. Conversely, raloxifene acts in concert with estrogen to protect against and reduce atherogenesis.
- What is a prevention strategy for this disease?
The best long-term approach to osteoporosis is prevention. If children and young adults, particularly women, have a good diet (with enough calcium and vitamin D) and get plenty of exercise, then they will build up and maintain bone mass. This will provide a good reserve against bone loss later in life. Exercise places stress on bones that builds up bone mass, particularly skeletal loading from muscle contraction with weight training exercises. However, any exercise of any type is better than none at all, and exercise also provides benefits for prevention of cardiovascular diseases that are more common in the elderly. Athletes tend to have greater bone mass than non-athletes. Exercise in later life will help to retard the rate of bone loss.
