Osteoporosis

By Edward S. Pratt, M.D., M.B.A.

We all start life with largely cartilaginous skeletons. We gather bone mass through our childhood and early adult years peaking around 25 to 30. From that point on our skeletons gradually lose bone mineral. The sex hormones appear to provide some protective effect against bone loss, although poor diet, obesity and a sedentary lifestyle can hasten its coming. Losses of greater than 50% or more of bone mineral increase the chances for an osteoporosis related fracture. Women have a particularly difficult time immediately following menopause when estrogen levels fall. Loss of bone mineral can approach 3% per year for the first decade following menopause, leaving women at risk of developing osteoporosis. Taking basic preventative steps can reduce this rate to about 1% per year (about the same rate as men).

Osteoporosis is a condition in which the amount of bone mineral within or skeleton drops to dangerously low levels. Those bones that support our weight such as the spine and hip are the most at risk. Bones that are profoundly involved in osteoporosis can be caused to fracture with an activity as simple as a cough or sneeze. Over 700,000 fractures of the spine related to osteoporosis occur each year. It has been shown that vertebral compression fractures caused by osteoporosis can decrease lung capacity; throw off walking balance increasing the risk of additional falls and fractures, lead to secondary problems with muscle and bone loss, loss of independence, depression and a 25% increase in mortality within five years.

Although osteoporosis favors women, nearly one fourth of its victims are men. Individuals who are blonde haired and blue eyed, have a positive family history, women who have had early menopause, or hysterectomy without hormone replacement, individuals who have been chronically ill or have taken oral steroids are the most at risk.

Taking a few preventative steps can help our friend the back from weakening to the point of fracture. Multiple fractures can lead to progressive “dowager’s hump” deformity and forced dependency. These preventative steps include adequate weight bearing exercise and calcium intake (1200mg/day), with enough Vitamin D to allow absorption of dietary calcium (about 800IU/day). Estrogen supplementation can also limit bone loss during the first decade after menopause, unless there is a family history of breast cancer which can make estrogen replacement a poor choice. Individuals at risk for developing osteoporosis can undergo an inexpensive test (DEXA scan) to measure bone density. If bone mineral levels fall to one standard deviation below the mean (osteopenia) additional medications such as Fosamax or Actonel are indicated. These medications can reverse the trend for bone loss, but can be hard on the stomach. A new intravenous medication (Forteo) holds great promise for those that are unable to tolerate these oral medications.

Patients with acute or sub acute compression fractures (less than 4-6 months old) can now be treated by a procedure called Kyphoplasty. This procedure consists of placing a small balloon within the broken vertebra, one on either side, and expanding the crushed vertebra back into shape. The balloon is then withdrawn and the hallow space inside the bone is filled with bone cement to act as an internal cast. Patients undergoing this procedure are not cured of their osteoporosis, however the pain associated with the compression fracture is minimized in over 90% or patients, with a complication rate associated with the procedure of only about 3 in 1000.