Bone health

Prevent bone fractures by preventing falls

by Dr. Susan E. Brown, PhD

Most of us have known people who’ve broken a bone after what seems like a minor accident — an elderly aunt who tripped on a carpet and fell, breaking her hip, or a middle-aged friend who stubbed her toe on a curb while walking her dog and found herself with a pair of broken wrists. People trip and fall all the time without breaking bones; why do these simple accidents have such serious consequences? Because when bone is weak, even minor trauma can cause it to break. This has been the source of the fear most people feel when told they have osteoporosis — the worry that sooner or later, they’ll fall, and their weakened bones won’t be able to withstand the blow.

But there are really two places where we can stop osteoporotic fractures from happening: we can strengthen the bones so they don’t break when we fall, and we can make it less likely that we’ll fall in the first place! For decades, efforts to prevent osteoporotic fractures have focused on the weakened bone component — trying to build bone strength by building bone density, so bone would be less vulnerable to breakage.

Naturally, any effort to replenish bone health makes complete sense. But while there is a growing awareness that simply having weak bones doesn’t make fractures inevitable, conditions that increase the risk of falling — such as poor balance and coordination, muscle weakness, and factors related to lifestyle — have an equally powerful bearing on a person’s risk of fracture.

A new way of looking at bone fractures

Finnish bone specialist Dr. Teppo Järvinen nicely summarizes this new perspective, saying that while conventional wisdom has been to screen for osteoporosis by bone densitometry and then to treat people with low bone density with drugs (such as Fosamax or Actonel), “the strongest single risk factor for fracture is falling, and not osteoporosis.”

This shift in focus from bone density to falls merits serious consideration, as we now know that simply having low bone density does not predict whether you’ll have a fracture. Most people are surprised to learn that the majority of people who experience so-called “osteoporotic” bone fractures do not actually have osteoporosis — their bone density might be low enough to diagnose osteopenia, but they may even have normal bone density. (See my article on rethinking the nature of osteoporosis for more details.) The kind of weakness in bone that leaves it vulnerable to fractures isn’t always visible in a bone scan; bone can be dense but weak, or alternatively, it can be thin, but still strong.

On the other hand, we can say conclusively that the vast majority of osteoporotic bone fractures occur as the result of a fall. This is especially true for hip fractures, where 90% are caused by falls, but also for some 50% of vertebral fractures, and most wrist and forearm fractures. And falls among people 65 years and older are very common, affecting one in three Americans in this age group. Even the middle-aged are prone to falls — approximately 30% of all women and 20% of all men older than 50 will fall each year.

While less than one fall in ten results in an identifiable fracture (it’s not known how many small or hairline fractures might go undiagnosed), 20% of all fall incidents require medical attention. Seeing osteoporotic fractures in this “numerical” light highlights the notion that to prevent bone fractures, we really need to focus on preventing falls.

So how do we prevent falls? In reviewing the growing scientific literature on falls, four major fall intervention areas stand out. These are:

• Building muscle strength
• Enhancing balance
• Using protective gear
• Modifying environmental factors

Let’s take a look at each for some practical tips we can all use to prevent falls and fractures.

Building strong muscles to prevent bone fractures: the role of vitamin D

We’ve known for some time that vitamin D plays a role in our ability to absorb calcium, so many researchers thought that giving people vitamin D would improve calcium absorption, increase a patient’s bone density, and thus help prevent fractures. Early in the clinical trials testing this idea, a surprising observation was made. Not only did a modest dose of vitamin D (700–800 IU D3 daily) dramatically reduce fracture incidence, but amazingly, the reduction was observed within a few months of starting the vitamin D therapy. The researchers had expected that this would be the case over time, but were very surprised to see fracture incidence fall so quickly. How could vitamin D work so fast to strengthen bones?

The answer to this question was, simply, that it didn’t — it strengthened muscles, which meant that the people taking part in the trial were stronger and therefore fell less often. (Over time, however, vitamin D does significantly help to strengthen bone as well. Read our articles on vitamin D to learn more.) The researchers had discovered that vitamin D, the “sunshine vitamin,” has a direct action on muscles. Vitamin D, we now know, directly and quickly enhances muscle mass, strength, and coordination, and it reduces body sway — all of which increase our stability and balance, making it less likely that we’ll fall (and helping us to better catch ourselves when we do lose our balance). Vitamin D deficiency, on the other hand, causes weakened muscles and poor coordination, and thus increased falls.

Many studies support the finding that vitamin D supplementation significantly reduces falls. One recent study, in fact, reported a 72% reduction in falls in an elderly population after five months of treatment with 800 IU of vitamin D. Another study observed a 49% reduction in falls among women in geriatric-care facilities using a combination of 800 IU vitamin D3 and 1200 mg calcium carbonate in comparison to those given just 1200 mg calcium carbonate alone.

Simply adding vitamin D isn’t the sole factor in preventing falls — muscles that aren’t used regularly won’t grow stronger, so exercising for muscle strength is crucial. Muscle mass and bone mass change together — if your muscles strengthen, so do your bones, but if you lose muscle, you also lose bone. Several studies show that in just ten weeks, weight training undertaken by sedentary elders can increase their muscle mass by 15–20% and can double their muscle strength. Even more, Dr. William Evans working at the Knool Laboratory for Human Performance Research at Penn State University reported that their exercise program has shown that a 95-year-old can become as physically fit as a healthy 50-year-old, and a 65-year-old as physically fit as a healthy 30-year-old! This bone–muscle link is made even stronger by data showing that the anti-fracture benefits of strength training persist over time.

But does all this exercise and strength training actually prevent people from falling? Several clinical trials and large meta-analyses document that it does. For example, a New Zealand study of older women and men found that a nurse-delivered home exercise program reduced falls nearly by half. In fact, programs developed by physical therapists that targeted fall reduction using strength training in combination with balance enhancement and gait training were perhaps the most effective in significantly reducing falls.

Addressing impaired balance to prevent falls

A novel Swedish study interviewed 84% of all Swedish twins aged 55 and older and asked them one simple question: “Do you have impaired balance?” Over time it was shown that when one twin answered “yes” and the other “no,” the twin with impaired balance had three times the risk of hip fracture as the twin with normal balance. Overall, one-third of all hip fractures could be attributed to impaired balance.

Balance and aging — the connection isn’t what you think

Proper balance while walking is a complex function involving the coordinated action of muscles, bones, vision, and the somatosensory system (the sensory system that regulates touch, pain, and the perception of the body’s positioning and motion). Balance problems, along with the fear of falling and decreased mobility, are the main reasons that elderly people enter assisted living and nursing homes. These concerns, in fact, account for 50% of nursing home admissions. Gait problems and balance problems such as amount of sway (side-to-side or forward–backward motion of the upper body while walking) can develop slowly and can perhaps go unnoticed.

But the decline in upright balance typically associated with aging is in fact not a result of aging at all — it’s really the result of physical inactivity associated with a sedentary lifestyle. Studies clearly show that when elders take part in therapeutic physical activity programs, their upright balance can be enhanced, and declines in balance are often prevented. An increase in the strength of the quadriceps (lower thigh) muscles and a significant decrease in postural sway in older adults were reported following just ten weeks of moderate aerobic and strength-training exercises. In another study of postmenopausal women, significant reduction in lateral body sway and increases in both lower body muscular strength and lean leg mass were reported following nine months of progressive walking while wearing a weighted vest. Yoga, qi gong and t’ai chi chuan are some other gentle practices to increase balance and reduce falls. Among men and women 70 years or older, for example, those who undertook a 15-week, moderate t’ai chi practice experienced a 50% reduction in falls.

There really is such a thing as “balanced” nutrition

Nutrition habits can also affect balance. Skipping meals will cause blood sugar levels to fluctuate abnormally. This can lead to drastic decreases in energy, clarity of thought, and muscle control. Using stimulants such as coffee and soda regularly also upsets blood sugar levels, which decreases the brain’s ability to consciously control the muscles. Regular meals, snacks, and minimal use of caffeine and sugar provide consistent energy, steady blood sugar levels, and indirectly sustain good balance. Alcohol and illicit drug use can also impair balance, increasing the risk of falls.

How vision affects balance

Our eyes provide signals to our somatosensory system that help determine our sense of position in the world, so it makes sense that balance can be affected by poor vision. Many factors can limit vision — and indirectly affect balance — such as wearing inappropriate prescription lenses, glaucoma, or cataracts. Since changes in eyesight often happen so gradually, you may not notice a decrease in your visual acuity. Poor depth perception and poor low-frequency contrast sensitivity (night vision) have both been found to increase a person’s risk of fracture from a fall. Regular vision exams are therefore an important component of fall prevention.

Side effects of medications

Finally — just as drugs of abuse can — many prescription medications and mood-altering drugs can cause dizziness or lack of coordination and thus increase the risk of falling. For example, the use of long-half-life, mood-altering psychotrophic drugs like Valium and Librium have been associated with a 70–80% increased risk of hip fracture.

Medicines that may increase the risk of falling include:

• Various heart medications
• Antidepressants
• Muscle relaxants
• Sedatives or sleeping pills
• Drugs that lower blood pressure
• Anticonvulsants

If you are currently taking any medications that cause dizziness or lack of coordination, speak with your healthcare provider. Perhaps there is an alternative medication available, or it might be possible to lower the dose of your current medication.

Using protective gear to prevent bone fractures

Hip fractures are undoubtedly the most serious and life-threatening of all osteoporotic fractures. In the US and many other Western countries, one in six Caucasian women over 50 will suffer a hip fracture, as will 6% of all Caucasian men over 50. The fact that most occur as a result of falling sideways and not from compression has given birth to hip protective gear for the frail.

While there are several types of hip protectors, a Finnish study of 1801 ambulatory but frail elderly tested whether protective oval-shaped pads worn inside pockets on a stretchy undergarment helped to prevent hip fractures. The pads reduced the impact of a sideways fall, thus significantly reducing hip fractures. In this study there was a 60% reduction in hip fractures among those study participants assigned to the use of these anatomically designed external hip protectors. Even more, the authors concluded from their trial that the risk of hip fracture can be decreased by more than 80% if the protector is worn at the time of a fall.

And in Japan, where osteoporosis is most common in women at and post menopause, a company has been testing prototype “airbags” for fall protection. These airbags inflate within seconds when a backward fall is detected, cushioning the wearer ahead of striking the ground.

Though not yet widely available, various kinds of fall protection like these described here may be useful in preventing fractures not just among the elderly, disabled, or those with frail bones, but also for people whose hobbies and work lives have them walking on tricky surfaces often — stairways, snow and ice, or steep inclines — or simply wearing the precarious footwear styles so many women love!

Environmental modifications help prevent falls and fractures

If falls are a concern for you, it’s also possible to change your home environment to make it less likely you’ll fall. Take a critical look at your home — do you have loose rugs, slippery wooden or tile floors, or furniture that clutters up areas where you walk? Is your home dimly lit? Making sure there’s nothing to trip you up, and that you can see where you’re going, can greatly decrease your chances of falling. One study suggested that if uncarpeted wooden floors were replaced with carpeted surfaces in nursing homes, the risk of hip fracture would be reduced by nearly 80%, and this advice is equally sensible for people living in their own homes. The box at right provides a list of simple environmental modifications that can go a long way in reducing needless falls and fractures.

Think about strength, think about balance

There are many factors that contribute to osteoporotic fractures, so it should come as no surprise that preventing fractures is a process with several steps. Taking precautions to avoid needless falls (and minimizing the impact of falls when they do occur) clearly has many benefits. Fortunately, we have access to a wide range of methods to regain balance and strength even as we age or if we are disabled. New branches of physical therapy, chiropractic and exercise therapy, and nutrition, as well as the ancient sciences of t’ai chi, qi gong, and yoga can indeed help bring us back “into balance” at any age.

Related to this article:
References & further reading on preventing bone fractures by preventing falls

 

Last Modified: 05/25/2011
Principal Author: Dr. Susan E. Brown, PhD