Osteoporosis is a condition where loss of bone develops to the point where our bones break easily. It is a serious condition that increases slowly as we age. Generally osteoporosis is asymptomatic (we are unaware that we have it) until there is a fall or injury resulting in a fracture. We all get osteoporosis as we age so it is important that we learn about it and try to do something to slow it down or reverse the process.

Common areas of the body where osteoporosis fractures occur:

  • the wrist - usually following a fall on the outstretched hand
  • the hip - often from slipping and twisting during a fall
  • the spine - from bending forward or heavy lifting

Bone tissue is a rigid, living structure that is constantly renewing itself. It is not an unchanging skeleton made of calcium. Microscopic holes are constantly created by bone eating cells called osteoclasts. Once these bone cavities are created, bone building cells called osteoblasts form new bone. This process rejuvenates the bone and repairs any damage.

In early childhood and adolescent years our bones grow rapidly. Good dietary calcium intake and regular exercise in these formative years are important for good bone health and peak bone mass. Bones may reach their mature length or height in the late teens but bone density and strength continue to build along with body weight and muscle strength into one's 20s and possibly 30s.

Once peak bone mass is reached, both women and men start losing bone at a rate of 0.5% to 1% loss per year. By age 60, your bone mass can have decreased by 30% compared to your bone mass at age 30. In women, the hormone estrogen contributes to the bone-building process, so as estrogen levels fall when women approach menopause, the bone loss accelerates to a rate of 2% to 3% per year. In this case, bone mass can decrease over 50% by age 60, compared to bone mass at age 30. This makes it particularly important to increase your intake of vitamin D and calcium, and explore other treatments such as with calcitonin and biophosphonates.

As we approach our later decades of life, many changing conditions make us more susceptible to fractures related to osteoporosis. The most important of these are decreased bone strength and increased risk of falls.

We are more likely to fracture a bone as we get older because of these reasons:

  • decreased bone strength due to reduced bone density
  • increased tendency to fall due to:
    • reduced muscle strength so we are less likely to break a fall
    • decreased vision, making it more likely for us to trip
    • poor balance mechanism making us more unsteady on our feet
    • posture changes resulting in center of gravity changes and more sway as we walk
    • changes in blood pressure or heart rate resulting in dizziness and unpredictable falls
    • medications that result in weakness or lightheadedness

Obviously, efforts should be made to minimize osteoporosis fractures before they happen. Physicians can identify individuals at high risk of osteoporotic fractures by doing a bone density test. It is also important to investigate whether the person is at a higher risk than normal for falling, especially if something can be done to reduce that risk.

John P. Wade, MD 
in association with the MediResource Clinical Team