Osteoporosis is a condition in which the bones become weak and fragile, often resulting in fracture of a bone. The condition is most commonly associated with older women, but can occur in men and in those with certain medical histories. With the rising age of the population, osteoporosis has become diagnosed more frequently, according to an article in the May 6, 2008, "Annals of Internal Medicine." It is primarily diagnosed by a test called dual energy X-ray absorptiometry, or DEXA scan, but can also be suggested by an exam involving ultrasound of the heel.
Indications
The U.S. Preventive Services Task Force recommends screening for osteoporosis in all women 65 years and older, and in women 60-64 years with increased fracture risk. In addition, men with selected risk factors should be screened. Though DEXA is generally accepted to be the superior test, heel ultrasound offers another testing option.
How It's Performed
Heel ultrasound is performed by placing an ultrasound probe on either heel of the foot. Sound waves are then transmitted through the bone of the heel, and a calculation of the bone’s density is made.
Results
Bone density is measured by something called a “T-score.” This compares the measurement of the bone’s density to that of a young person. A T-score of -2.5 qualifies as osteoporosis, while a T-score of -1 to -2.5 suggests osteopenia, or a thinning of the bones. Any heel ultrasound score of -1 or lower should be confirmed by a DEXA if possible.
Drawbacks
Results of heel ultrasound do not correlate well enough with DEXA results to be used to monitor treatment for osteoporosis. Heel ultrasound is traditionally used as a way to screen for, rather than diagnose, osteoporosis. It may be helpful to help identify those at risk for osteoporosis. Evidence has shown that a heel ultrasound T-score of -1.0 picks up 75 percent of osteoporosis, but of those only 66 percent were truly osteoporotic.
Benefits
As opposed to a DEXA scan, heel ultrasound provides no radiation. It is also performed more quickly and less expensively than DEXA, according to the "Annals of Internal Medicine" article. In addition, a heel ultrasound unit is generally portable, making it ideal for screening at health fairs, etc. Some studies have suggested that heel ultrasound can effectively predict fracture risk.
References
- "Annals of Internal Medicine:" Screening for Osteoporosis in Men: A Clinical Practice Guideline from the American College of Physicians
- "Osteoporosis International:" Quantitative Heel Ultrasound in a Population-based Study in Italy and Its Relationship With Fracture History
- “American Family Physician”; Diagnosis and Treatment of Osteoporosis; Feb. 1, 2009.
