The Truth About AFOs And Fall Prevention
Recently, a prominent podiatric company began marketing an ankle-foot orthosis (AFO) as the centerpiece of a fall prevention program targeted at elderly patients. To learn that a commonly used orthopedic device could now be used to prevent a catastrophic medical event would prompt any reasonable practitioner to look for the scientific evidence that could validate such a profound accomplishment.
After conducting a search of the medical literature, I am both disappointed and astonished to learn that there are no valid scientific studies to prove that any AFO can prevent falls in any patient population. Even more surprising is the credible scientific evidence that certain AFO braces may actually compromise balance and postural control. This could put certain patient populations at a greater risk for catastrophic falls.
I became interested in the biomechanics of ankle-foot orthoses when I designed and patented several ankle braces in the mid-1990s. I focused much of my research on balance, proprioception and neuromuscular control of the lower extremity.1 Later, I published a review of fascinating research that had been conducted on balance, postural control and prevention of ankle sprains using foot orthoses as the only treatment intervention.2,3
During this time, I realized that multiple disciplines studying the cause and prevention of falls in the elderly community had been conducting the research. Much of the knowledge about neuromuscular control in athletes appeared to have some relevance to fall prevention in the elderly. I was pleasantly surprised to learn that our podiatric colleagues in Australia contributed a substantial amount of knowledge and insight into fall prevention. They now lead the world in teaching the role of podiatry in fall prevention.4-7
Last year, at the American Podiatric Medical Association (APMA) National Meeting, I had the honor of presenting an overview of the research that our Australian podiatric colleagues had conducted. I presented an entire lecture devoted to fall prevention. In this lecture, I pointed out the key components of the fall prevention program, which were recently published in the British Medical Journal.8 The essential elements of this program include a subsidy and education for selection of footwear, a prefabricated foam foot orthosis, a home-based foot exercise program, regular podiatric care and a take-home educational brochure on fall prevention. Podiatric physicians implemented this multifaceted program, which reduced falls in elderly patients by an astounding rate of 26 percent.
At the APMA National, I also reviewed the role of AFOs and risk of falls, summarizing the current scientific research. The bulk of today’s research documents the negative effects of AFOs on balance and postural control. The problem is so significant that the American Academy of Orthotists and Prosthetists held a special conference to study the effects of AFOs on balance in June 2010.
In the proceedings of this conference, Ramstrand and Ramstrand performed a systematic review looking at all studies of AFOs and their effects on balance.9 Most of the studies have focused on patient populations who commonly use AFOs: those with hemiplegic, traumatic brain injury, cerebral palsy and multiple sclerosis. This review found mostly negative effects on balance with any type of solid or ankle restrictive AFO device. Researchers discovered minimal effects on balance with hinged AFO devices, either positive or negative.
There is some evidence that posterior leaf-spring AFOs may improve balance and postural control in patients with hemiplegia, but this has not been proven in other patient populations, including the elderly.9 However, the authors caution that “of particular interest were rigid orthoses that resulted in either no change or improvement of performance on static balance tests but deterioration in performance under dynamic test conditions. This result is not surprising given that dynamic balance requires a degree of ankle joint motion that is intentionally inhibited in rigid orthoses.”9
There have been no studies published showing positive effects of AFOs to improve balance and postural control in elderly adults during dynamic gait. Furthermore, there have been no studies published to show that any type of AFO will prevent falls in any patient population, let alone elderly subjects. An excellent overview, recently published in Lower Extremity Review, highlighted the role of AFOs in balance and falls.10
Could Unsubstantiated Claims About Prevention Adversely Affect Medicare Coverage Of AFOs?
My other concern is the perception that practitioners may have that an AFO prescribed to prevent falls in a patient at risk would be covered by most insurance companies including Medicare and Medicaid. I would ask how such a device could be eligible when the primary indication is the prevention of an event rather than the treatment of an actual medical condition.
While we often prescribe foot orthoses or ankle-foot orthoses to treat a medical condition, we almost never tell our patients that wearing such a device will prevent an event. A medical event such as a heart attack, stroke or catastrophic fall is a profound occurrence that can lead to death. The cause of such events is always multifactorial.
Over the years, many have developed clinical interventions and pharmaceutical products with a goal of preventing an event such as a heart attack or stroke. Researchers have invested billions of dollars in Level 1 studies to prove that the intervention has a significant preventive effect. No credible company or individual would market a product to the medical profession with a claim that the product could prevent a catastrophic event without doing their due diligence in conducting appropriate clinical trials. Certainly, the FDA would prohibit any marketing of a device intended to prevent an event that did not have multiple Level 1 scientific evidence to back up the claims.
From a public health perspective, falls in the elderly are just as important as heart attacks and strokes. One in three adults over the age of 65 suffers an accidental fall each year and half of these falls result in some type of injury.11 Falls are the leading cause of injury in older adults and are the leading cause of death in people over the age of 85.12,13 Therefore, a physician or company who announces a new technology that will prevent a catastrophic event such as a traumatic fall would certainly garner attention and scrutiny of such a monumental achievement.
When this technology has no published research to back up its claim, the initial ramifications for the podiatric profession are not only embarrassing, they could affect our Durable Medical Equipment provider status with Medicare. Prevention of falls is not an indication for prescribing an AFO, according to the current published Medicare guidelines. If podiatric physicians begin prescribing bilateral AFOs to elderly patients with this treatment goal in mind, Medicare is certainly going to take notice. Scrutiny of everything we do with these valuable devices is likely to follow.
I will continue to support any program or initiative that will potentially reduce the risk of falls in any patient population. As our Australian colleagues have already demonstrated, podiatric physicians can play a critical role in fall prevention in the elderly. None of the evidence validates the use of any type of AFO in such a program. If convincing Level 1 evidence becomes available that certain designs of ankle-foot orthoses can prevent falls, I will add that clinical indication in the promotion of any device, including my own current line of products that meet the criteria.
Until that happens, I will continue to educate and inform my colleagues of the credible scientific evidence relative to fall prevention so they can make the right decisions for their patients.
1. Richie DH. Functional instability of the ankle and the role of neuromuscular control. A Comprehensive Review. J Foot Ankle Surg. 2001; 40(4):240-251.
2. Richie DH Jr. Effects of foot orthoses on patients with chronic ankle instability. J Am Podiatr Med Assoc. 2007; 97(1):19-30.
3. Rome K, Richie D Jr, Hatton AL. Can orthoses and insoles have an impact on postural stability? Podiatry Today. 2010; 23(10):43-51.
4. Sherrington C, Menz HB. An evaluation of footwear worn at the time of fall-related hip fracture. Age Ageing. 2003; 32(3):310-4.
5. Menz HB, Morris ME, Lord SR. Footwear characteristics and risk of indoor and outdoor falls in older people. Gerontology 2006; 52(3):174-80.
6. Menz HB, Morris ME, Lord SR. Foot and ankle risk factors for falls in older people: a prospective study. J Gerontol A Biol Sci Med Sci. 2006; 61(8):866-70.
7. Mickle KJ, Munro BJ, Lord SR, Menz HB, Steele JR. ISB Clinical Biomechanics Award 2009: toe weakness and deformity increase the risk of falls in older people. Clin Biomech. 2009; 24:787-91.
8. Spink MJ, Henz HB, Fotoohabadi MR, et al. Effectiveness of a multifaceted podiatry intervention to prevent falls in community dwelling older people with disabling foot pain: randomized controlled trial. BMJ 2011;342:d3411 doi:10.1136/bmj.d3411
9. Ramstrand N, Ramstrand S. AAOP State-of-the-science evidence report: the effect of ankle-foot orthoses on balance — a systematic review. SSC Proceedings 10: P4-P23, Oct 2010.
10. Groner C. Upstanding interventions: falls prevention in O&P. Lower Extremity Rev. 2011. Available at http://www.lowerextremityreview.com/cover_story/upstanding-interventions... .
11. Larsen ER, Mosekilde L, Foldspang A. Correlates of falling during 24 h among elderly Danish community residents. Prev Med. 2004; 39(2):389-98.
12. Centers for Disease Control and Prevention. Falls among older adults: An overview. Available at: http://www.cdc.gov/HomeandRecreationalSafety/Falls/adultfalls.html . Accessed February 25, 2011.
13. Centers for Disease Control and Prevention. Web–based Injury Statistics Query and Reporting System (WISQARS). Available at: http://www.cdc.gov/injury/wisqars . Accessed February 25, 2011.