Point-Counterpoint: Do AFOs Have A Role In Fall Prevention?

Yes.

This author has found that custom dynamic ankle-foot orthotics (AFOs) can be helpful in addressing underlying proprioceptive deficits in patients at risk for falls and identifies key factors in assessing and treating these patients.

By Jeffrey C. Christensen, DPM, FACFAS

Falls in the elderly pose a significant public health burden and annually affect one-third of people over the age of 65.1-3 Approximately 20 percent of falls result in serious injury, including hip fractures and death.4,5 In addition to age-related sensorimotor decline, a myriad of underlying etiological factors can contribute to imbalance. These include: polypharmacy; chronic neurological disease (i.e. post-stroke hemiparesis, multiple sclerosis, diabetes and Parkinson’s disease); cognitive impairment; visual or vestibular impairments; arthritis; lower extremity disabilities; and gait disorders.6-9

   Fall risk in the elderly increases, especially during dynamic conditions, as the body center of mass during single limb support projects external to the base of support. In this compromised group, reduced gait speed, stride length, cadence and joint movements are evident. Specific balance impairments include increased postural sway in quiet stance, delayed response to postural perturbations and reduced ability to move toward their limits of stability.6,10 A delayed response to loss of balance can make balance recovery difficult, potentially leading to a fall. Treatment interventions can address and modify many of these deficiencies.

   In general, I favor using ankle-foot orthoses (AFO) for elderly patients with specific lower extremity balance deficiencies. For my patients, I incorporate a targeted balance rehabilitation program, which often includes lightweight AFO devices with stable shoes, to address underlying proprioceptive deficits with the goals of reducing fall risk and improving functional gait.

Keys To Identifying And Treating Patients At Risk For Falls

Along with a working understanding of balance dysfunction, evaluation and management of this patient segment, treatment requires a rational, methodical and multidisciplinary approach.11 Physical and occupational therapists, primary care physicians and podiatrists should be part of the treatment team that actively engages their at-risk patients. Asking about recent falls or near falls is necessary since independent seniors may be fearful about disclosing their missteps to their medical providers for fear of repercussions.

   Podiatric assessment is critical in patients with balance disorders. A study of 1,000 random community dwellers over 65 years old found that 36 percent of the group had significant foot and leg problems, and compromise in balance function.12 A recent Australian-based, randomized controlled trial further confirmed this, showing that active podiatric management can reduce fall risk in the elderly.13 Other investigations have linked significant measurable fall risks with foot and ankle problems. These foot and ankle conditions include: digital deformities, hallux valgus, muscle weakness, ankle instability/malalignments, tendon contractures, adult-acquired flatfoot and peripheral neuropathy.4,5,11,14-22

   Documentation of fall frequency and a fall risk assessment can happen through simple balance screening and focused podiatric treatment. Evaluating patients with multiple and variable disease expressions can be confusing as patients with age-related muscle weakness, lack of coordination or joint instability can still have falls. It is best to identify and focus on pathophysiological and mechanical deficiencies, irrespective of diseases that may or may not be present.23

   A targeted low-tech approach can be helpful in assessing any patient’s sensorimotor abilities. I recommend ascertaining a simple fall history and a clinical test called the “Timed-Up-and-Go” test for screening.24 It involves timing a patient getting up from a chair, walking 3 meters, turning around to return to the chair and sitting back down. The validated tool is very useful in determining patients who are most at risk for falling.24 A Timed-Up-and-Go time greater than 14 seconds is abnormal for community seniors and warrants further assessment.24

   I recommend a treatment program that educates the patient and family, eliminates home obstacles, addresses individual sensorimotor deficiencies (including lower extremity issues) and promotes regular exercise. Such multifactorial programs have demonstrated significant fall risk reduction.25,26 The prescribed use of AFOs for fall prevention is particularly well documented in elderly post-stroke patients. A recent meta-analysis of 20 clinical trials involving 314 post-stoke patients with AFOs showed improved lower extremity kinematics, kinetics and energy cost in walking.27

   Patients who fall often are psychologically compromised. They may self-restrict their activities, which can lead to further deconditioning. Patients need to overcome this loss of confidence for long-term success. Ankle-foot orthoses can restore that confidence along with gait velocity and the functional improvement that results in a transition to a higher level of ambulation and quality of life.28,29 However, to improve adherence, the device needs to be easy to use, fit easily into standard shoes and be made of lightweight materials for patients to avoid fatigue.

What You Should Know About Prescribing AFOs In Older Patients

Like many current treatments in medicine, there is a need for continued research in lower extremity compromised elderly patients. While there is anecdotal clinical evidence of efficacy and benefit of dynamic AFOs, more formal investigations are warranted to show measurable benefit and permit refinement of brace designs.

   There has been some recent confusion around the indication and prescription of custom AFO therapy in older adults. One should never prescribe custom braces in a prophylactic manner to prevent falls. For clarification, a list of common indications for prescribing custom AFOs includes: muscle weakness, ataxia, gait abnormality, joint instability, difficulty walking, peripheral neuropathy, limb pain, arthropathy and hemiplegia. Treating these conditions as outlined will have a benefit in reducing fall risk but not totally eliminate falls.

   The question often arises: how do we justify bilateral use of these braces in patients with these lower extremity deficiencies? First, one needs to document bilateral involvement. Furthermore, one can chart subjective and objective clinical benefit, including retesting Timed Up and Go times if necessary. Additionally, there is literature to support this treatment application as dynamic bilateral AFO support has had successful testing in multiple sclerosis patients, who have similar balance disorder profiles to that of compromised elderly patients.30,31 It is important to note that static AFOs, which restrict ankle motion during the stance phase of gait, do not perform well functionally.31-33 Static AFOs can potentially cause increased limitations on soft surfaces and therefore one should avoid them when possible.31-33

   Why can’t we use over-the-counter AFOs instead of custom devices? There is evidence that demonstrates a custom dynamic AFO that maximizes arch contour and leg surface area can show immediate clinical benefit.34 The flexible AFO brace design provides sagittal plane flexibility to preserve ankle motion while maintaining frontal plane support. The upper portion of the brace also provides important tactile stimulus to the leg that improves proprioceptive sense and postural stability.35

In Conclusion

An individual’s fall risk depends on the frequency of imbalance episodes he or she encounters in daily activities, and his or her ability to recover from these balance-threatening situations.

   Physicians can take a rational approach in dealing with elderly patients suffering from lower extremity sensorimotor deficiencies and fall risk by implementing a targeted multifactorial treatment plan that incorporates physical therapy and use of custom dynamic AFO devices. This can improve their patients’ balance control and quality of life.

   Dr. Christensen is in private practice at Ankle & Foot Clinics Northwest in Everett, Wash. He is the Founder and Director of the Northwest Surgical Biomechanics Research Laboratory, a division of the International Foot and Ankle Foundation for Education and Research. Dr. Christensen is a Fellow of the American College of Foot and Ankle Surgeons.

References

1. Blake AJ, Morgan K, Bendall MJ, Dallosso H, Ebrahim SB, Arie TH, Fentem PH, Bassey EJ. Falls by elderly people at home: prevalence and associated factors. Age Aging. 1988; 17(6):365-372.
2. Lord SR, Ward JA, Williams P, Anstey KJ. An epidemiological study of falls in older community-dwelling women: the Randwick falls and fractures study. Aust J Public Health 1993; 17(3):240-254.
3. Tinetti ME, Speechley M, Ginter SF. Risk factors for falls among elderly persons living in the community. N Engl J Med 1988; 319(26):1701-1707.
4. Lord SR. Falls in the elderly: admissions, bed use, outcome and projections. Med J Aust. 1990; 153(2):117-118.
5. Speechley M, Tinetti ME. Falls and injuries in frail and vigorous community elderly persons. J Am Geriatr Soc. 1991; 39(1):46–52.
6. Granacher U, Muehlbauer T, Gollhofer A, Kressig RW, Zahner L. An intergenerational approach in the promotion of balance and strength for fall prevention – a mini-review. Gerontology. 2011; 57(4):304–315.
7. Lord SR, Sherrington C, Menz HB. Falls in Older People: Risk Factors and Strategies for Prevention. 2nd ed. Cambridge University Press, Cambridge, 2007.
8. Spink MJ, Fotoohabadi MR, Wee E, Hill KD, Lord SR, Menz HB. Foot and ankle strength, range of motion, posture, and deformity are associated with balance and functional ability in older adults. Arch Phys Med Rehabil. 2011; 92(1):68-75.
9. Wallmann HW. The basics of balance and falls. Home Health Care Management Practice 2009; 21:436-439.
10. Sturnieks D, Menant J, Delbaere K, et al. Force-controlled balance perturbations associated with falls in older people: a prospective cohort study. PLoS ONE. 2013; 8(8):1-6.
11. Menz HB, Hill KD. Podiatric involvement in multidisciplinary falls-prevention clinics in Australia. J Am Pod Med Assoc. 2007; 97(5):377-384.
12. Barr E, Browning C, Lord S, Menz HB, Kendig H. Foot and leg problems are important determinants of functional status in community dwelling older people. Disabil Rehabil. 2005; 27(16):917–923.
13. Spink MJ, Menz HB, Fotoohabadi MR, et al. Effectiveness of a multifaceted podiatry intervention to prevent falls in community dwelling older people with disabling foot pain: randomised controlled trial. Br Med J. 2011; 342:1-8.
14. Menz HB, Lord S. Foot pain impairs balance and functional ability in community- dwelling older people. J Am Pod Med Assoc. 2001; 91(5):222-229.
15. Menz HB, Lord S. The contribution of foot problems to mobility impairment and falls in community-dwelling older people. J Am Geriatr Soc. 2001; 49(12):1651-1656.
16. Menz HB, Lord S. Gait instability in older people with hallux valgus. Foot Ankle Int. 2005; 26(6):483-489.
17. Menz HB, Lord SR. Foot pain impairs balance and functional ability in community-dwelling older people. J Am Podiatr Med Assoc. 2001; 91(5):222-229.
18. Menz HB, Morris ME, Lord S. Foot and ankle characteristics associated with impaired balance and functional ability in older people. J Gerontology A Biol Sci Med Sci. 2005; 60(12):1546-1552.
19. Mickle KJ, Munro BJ, Lord S, Menz HB, Steele JR. Toe weakness and deformity increase the risk of falls in older people. Clinical Biomechanics. 2009; 24(10):787-791.
20. Mickle KJ, Munro BJ, Lord S, Menz HB, Steele JR. Foot pain, plantar pressures, and falls in older people: a prospective study. J Am Geriatr Soc. 2010; 58(10):1936-1940.
21. Mickle KJ, Munro BJ, Lord S, Menz HB, Steele JR. Cross-sectional analysis of foot function, functional ability, and health-related quality of life in older people with disabling foot pain. Arthritis Care & Research. 2011; 63(11):1592-1598.
22. Mickle KJ, Munro BJ, Lord S, Menz HB, Steele JR. Gait, balance and plantar pressures in older people with toe deformities. Gait & Posture. 2011; 34(3):347–351.
23. Lord SR, Menz HB, Tiedemann A. A physiological profile approach to falls risk assessment and prevention. Physical Therapy. 2003; 83(3):237-252.
24. Shumway-Cook A, Brauer S, Woollacott M. Predicting the probability for falls in community-dwelling older adults using the Timed Up & Go Test. Phys Ther. 2000; 80(9):896-903.
25. Gillespie LD, Robertson MC, Gillespie WJ, et al. Interventions for preventing falls in older people living in the community (Review). Cochrane Database of Systematic Reviews. 2012; 12(9):1-408.
26. Tinnetti ME, Baker DI, McAvay G, et al. A multifactorial intervention to reduce the risk of falling among elderly people living in the community. NEJM. 1994; 331(13):821-827.
27. Tyson S, Sadeghi-Demneh E, Nester C. A systematic review and meta-analysis of the effect of an ankle-foot orthosis on gait biomechanics after stroke. Clin Rehabil 2013; epub ahead of print.
28. Zissimopoulos A, Fatone S, Gard S. The effect of ankle–foot orthoses on self-reported balance confidence in persons with chronic poststroke hemiplegia. Prosthet Orthot Int 2013; epub ahead of print.
29. Schmid A, Duncan P, Studenski S, et al. Improvements in speed-based gait classifications are meaningful. Stroke. 2007; 38(7):2096-2100.
30. Cameron MH, Lord S. Postural control in multiple sclerosis: implications for fall prevention. Curr Neurol Neurosci Rep. 2010; 10(5):407-412.
31. Cattaneo D, Mearazzini F, Crippa A, Cardini R. Do static or dynamic AFOs improve balance? Clinical Rehabilitation. 2002; 16(8):894–899.
32. Mueller K, Cornwall M, McPoil T, Mueller D, Barnwell J. Effect of a tone-inhibiting dynamic ankle-foot orthosis on the foot-loading pattern of a hemiplegic adult: a preliminary study. J Prosthetics Orthotics. 1991; 4:86-92.
33. Panwalkar NA. Role of Ankle Foot Orthoses in the Outcome of Clinical Tests of Balance: Rehabilitation Sciences, University of Illinois at Chicago, 2010.
34. Pohl M, Mehrholz J. Immediate effects of an individually designed functional ankle-foot orthosis on stance and gait in hemiparetic patients. Clin Rehabil 2006; 20(4):324-330.
35. Menz HB, Lord S, Fitzpatrick RC. A tactile stimulus applied to the leg improves postural stability in young, old and neuropathic subjects. Neuroscience Letters. 2006; 406(1-2):23-26.

   For further reading, see “Keys To Prescribing AFOs For Senior Patients” in the August 2012 issue of Podiatry Today, “Troubleshooting AFOs” in the April 2005 issue, “Key Pearls For Prescribing AFOs” in the February 2003 issue or “How To Address And Prevent Complications With AFOs” in the September 2009 issue.

No.

Citing a lack of credible evidence on the merits of AFOs for fall prevention, this author notes that AFOs do not treat the underlying conditions that put patients at risk for falls and that the devices can actually increase fall risk.

By Douglas Richie Jr., DPM, FACFAS

The answer to this question is quite clear. Yes, ankle-foot orthoses (AFOs) do play a role in falls prevention as they can potentially increase the risk of traumatic falls in elderly patients. In terms of preventing catastrophic falls, there is no credible evidence in the scientific literature to support the notion that any type of ankle-foot orthosis will reduce the rate of falls in non-neurologic impaired elderly patients.

   The latest Cochrane Review of falls prevention evaluated 4,967 studies published in the scientific literature.1 This review found some strong statistical evidence for certain interventions for fall prevention. These included group exercise, home safety modification and withdrawal of psychotropic medication. In this gold standard, systematic review, there is no evidence supporting the notion that ankle-foot orthoses will prevent falls in non-neurologic impaired people. Need we go any further?

   This begs the question: Why are we even debating this issue? What started purely as a commercial venture has now somehow become a controversy in the podiatric profession. My colleagues need to step back and evaluate the facts behind this commercial venture and realize the ramifications of implementing a therapy based upon profit motive, which could potentially harm the end user, a vulnerable elderly patient.

   Unlike ordinary AFOs intended to treat neurologic and musculoskeletal conditions, a new “fall prevention AFO” promises to prevent a medical event.2 Never before in any branch of medicine has a single device been promoted and promised to prevent a traumatic fall, an event that carries as much public health importance as a heart attack or stroke.

   Yet, even more astounding is that thousands of senior citizens received this device before any valid research could determine if the lofty expectation of fall prevention could ever occur. Furthermore, the notion of prescribing bilateral, non-articulated AFO devices runs contrary to customary practice of ankle-foot orthotic therapy in this country.3 The safety of this practice has yet to have testing or validation.

A Closer Look At The Paucity Of Research On AFOs In Relation To Fall Prevention

Recently, I wrote in my Podiatry Today blog about new published research showing the negative effects of bilateral solid shell, non-articulated AFOs on balance and functional tasks.4 This study investigated the effects of semi-rigid, non-articulated AFO devices during several tests of balance in patients wearing AFOs bilaterally.5 In terms of clinical implications, this research revealed that semi-rigid non-articulated AFO devices negatively affected the ability to move, lean or reach. The authors concluded that bilateral, non-articulated AFO devices could affect functional tasks such as picking up an object from a shelf, initiation of gait and other essential activities. They point out how restricting ankle joint motion can compromise essential proprioceptive feedback from the ligaments, tendons and muscles around the ankle joint.

   Hadadi and colleagues have validated this notion in another study that measured a continuous decline in postural control when comparing soft ankle braces to a more restrictive semi-rigid brace.6 Despite how thin or flexible the plastic material, a non-articulating AFO will restrict motion more than the non-braced condition. There is convincing evidence that a solid shell, non-articulated AFO will compromise proprioception and balance, particularly in those populations already at risk for falling.7

   The proclamation that a new device could prevent a catastrophic event would normally be predicated upon a breakthrough study published in a peer-reviewed scientific publication. No credible physician would implement a new treatment protocol for such an important public health initiative such as fall prevention without examining the quality of research that supports the intervention.

   Yet this appears to be happening in the podiatric profession where many are not concerned about scientific evidence and might be focusing on Medicare reimbursement, which can be handsome for certain AFO products. Today, evidence-based medicine appears to have been ignored as a growing number of practitioners are implementing AFO therapy to prevent falls without any proof that this treatment really works. This begs the question: Why hasn’t the prescription of bilateral “fall prevention” AFO devices become mainstream amongst our MD colleagues?

   Early on, I raised concern about the promotion of so-called fall prevention AFOs in my blog in Podiatry Today.8 The response to my blog from the primary spokesperson of this intervention quoted studies that supposedly validate the notion that AFOs will prevent falls. However, scrutiny of these studies shows each and every time that the research cited has nothing to do with fall prevention in non-neurologically impaired senior citizens, who are the target of this marketing campaign. Falls brace advocates, who focus on severely impaired stroke patients, have cited laboratory studies on postural control and gait. In response to my blog, a spokesperson quoted other research, actually composed of studies of sport ankle braces on healthy athletes.8

   The promotion of AFOs for fall prevention has relied on misrepresentation of published articles that have no relevance to the prevention of falls in non-neurologic impaired senior citizens. I encourage the reader to read each and every study quoted by the fall brace advocates. It is disturbing to see that many times the results have been reported in a distorted fashion.

   I am aware that the fall prevention brace company has sponsored research showing changes in postural control with its devices. Only when this research is peer reviewed and published in a respected medical journal can we really begin to evaluate the findings. Furthermore, studies on postural control do not in any way prove that an intervention will prevent falls in elderly people. Improving postural control is not a valid medical indication for prescribing AFO devices, according to Medicare guidelines.

   To conform to Medicare guidelines, the fall prevention brace advertisements advocate identifying common musculoskeletal conditions normally treated with AFOs, which can justify the prescription of a fall prevention brace. Not only is this practice deceptive and potentially illegal, there is no validity to the notion that treating musculoskeletal conditions will prevent catastrophic falls.

Why The Argument About Treating Risk Factors Doesn’t Hold Up To Scrutiny

Let’s look at this argument that by treating known musculoskeletal risk factors, AFO devices will reduce the risk of falling in elderly patients. The fallacy of this argument is the fact that there is no evidence that AFO devices actually “treat” these risk factors in a way that the devices will actually prevent falls. It is well known in epidemiologic research that, while we can identify risk factors, treating the risk factors does not always ensure the prevention of the event or disease. Implementing AFO devices for osteoarthritis, muscle weakness or gait abnormality may improve the symptoms of these conditions but does not automatically translate into a lower rate of falling.

   For example, while osteoarthritis is a known risk factor for falling, one must ask: How does an AFO device change or modify osteoarthritis so it actually prevents falls? If AFO devices improved arthritis and prevented fall risk, studies would be available to prove this cause/effect relationship. Thus far, there are no such studies showing that treating arthritis with AFO devices will prevent falls.1 Similarly, there are no studies showing that when one uses AFO devices to treat muscle weakness, limited joint motion or gait abnormality, a significant reduction in the risk of falls will occur.8

Final Notes

There is better evidence that foot orthoses, not ankle-foot orthoses, will improve balance and reduce fall risk in elderly patients.9 One must ask: Why are podiatric physicians not implementing bilateral foot orthotic therapy to prevent falls in elderly patients rather than AFO devices? The answer may be the fact that Medicare does not cover custom foot orthoses but reimburses handsomely for custom AFO devices. One has to question the role that financial incentive is playing in this new, unproven intervention for fall prevention.

   Finally, one has to step back and realize that this whole controversy about prescribing bilateral solid shell AFO devices on elderly patients obscures the many positive aspects of fall prevention in podiatric practice. Last year, I wrote an article in Podiatry Today describing the positive role that podiatric physicians can play in identifying fall risk and implementing certain valid, proven interventions.10 One cannot let a commercial interest blur the significant and positive effects of valid fall prevention treatments implemented by the podiatric profession.

   Dr. Richie is an Adjunct Associate Professor within the Department of Applied Biomechanics at the California School of Podiatric Medicine at Samuel Merritt University in Oakland, Calif. He is a Fellow and Past President of the American Academy of Podiatric Sports Medicine. Dr. Richie is a Fellow of the American College of Foot and Ankle Surgeons. He is in private practice in Seal Beach, Calif. Dr. Richie writes a monthly blog for Podiatry Today. One can access his blog at www.podiatrytoday.com/blogs/301 .

References

1. Gillespie LD, Robertson MC, Gillespie WJ, Sherrington C, Gates S, Clemson LM, Lamb SE. Interventions for preventing falls in older people living in the community. Cochrane Database of Systematic Reviews 2012, Issue 9. Art. No.: CD007146. DOI: 10.1002/14651858.CD007146.pub3.
2. Moore Balance Brace. www.fallpreventionbrace.com . Accessed August 26, 2013.
3. Rubin G, Cohen E. Prostheses and orthoses for the foot and ankle. Clin Podiatr Med Surg. 1988; 5(3):695-719.
4. Richie D. New research warns of negative effects of AFOs on balance. Podiatry Today. Available at https://www.podiatrytoday.com/blogged/new-research-warns-negative-effect… . Published April 23, 2013. Accessed Aug. 26, 2013.
5. Panwalkar N, Aruin AS. Role of ankle foot orthoses in the outcome of clinical tests of balance. Disabil Rehabil Assist Technol. 2012; 8(4):314-20.
6. Hadadi M, Mazaheri M, Mousavi ME, Maroufi N, Bahramizadeh M, Fardipour S. Effects of soft and semi-rigid ankle orthoses on postural sway in people with and without functional ankle instability. J Sci Med Sport. 2011; 14(5):370-5.
7. Ramstrand N, Ramstrand S. The effect of ankle-foot orthoses on balance-a systematic review. Official Findings of the State–of-the-Science Conference. J Prosthet Orthot. 2010; 22(10):4-23.
8. Richie D. The truth about AFOs and Fall prevention. Podiatry Today. Available at https://www.podiatrytoday.com/blogged/truth-about-afos-and-fall-preventi… . Published Feb. 24, 2012. Accessed Aug. 26, 2013.
9. Spink MJ, Menz HB, Fotoohabadi MRF, Wee E, Landorf KB, Hill KD, Lord SR. 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
10. Richie D. Preventing falls in the elderly: where DPMs can have an impact. Podiatry Today. 2012; 25(9):38-51.