New Research Warns Of Negative Effects Of AFOs On Balance

Doug Richie Jr. DPM FACFAS

Researchers at the University of Illinois recently published a study that adds to the existing findings on the negative effects of ankle-foot orthoses (AFOs) on balance and postural control. Researchers continue to validate that semi-rigid, non-articulated AFO devices will compromise balance, particularly when patients wear the devices bilaterally.

The study investigated the effects of semi-rigid, non-articulated AFO devices during several tests of balance in patients wearing AFOs bilaterally.1 Two of the clinical tests utilized the SMART Balance Master® (NeuroCom, USA) computerized force platform to perform the modified Clinical Test of Sensory Interaction on Balance and the limits of stability test. Another clinical test was the common Functional Reach Test, which one can easily perform in the office setting with a tape measure. Researchers noted a significant negative impact on balance when the patients wore the AFO devices in each of the clinical tests.

The authors speculated that the compromise in balance performance caused by the non-articulated AFO devices was due to restriction of proprioceptive input from the muscles, tendons and other tissues around the ankle joint.1 The researchers point out that by design, AFOs limit the motion of the ankle joint in one or more planes. They speculate that this limitation of motion has significant effects on balance, particularly in those patients who are already compromised. The researchers observed that “when active ankle joint movements were constrained by the AFOs … the center of gravity sway was significantly larger as compared to the conditions with no AFOs.” The study emphasized that bilateral AFO therapy magnified the negative effects of these devices on proprioception and balance control.

In terms of clinical implications, the researchers point out that semi-rigid non-articulated AFO devices negatively affected the ability to move, lean or reach. This could affect functional tasks such as picking up an object from a shelf, initiation of gait and other essential activities.1

The authors add that these negative effects of restricting ankle motion were also recently validated in a published study from Hadadi and colleagues.2 In this investigation, researchers measured a continuous decline in postural control when comparing soft ankle braces to a more restrictive semi-rigid brace. Despite how thin or flexible the plastic material is, one can expect a solid shell, non-articulated AFO to compromise proprioception and balance.

These two studies validate a position I have taken regarding the prescription of bilateral, non-articulated AFO devices to elderly patients at risk of falling (see http://www.podiatrytoday.com/blogged/still-looking-documentation-afos-ef... and http://www.podiatrytoday.com/preventing-falls-elderly-where-dpms-can-hav... ). To this date, no study has validated an AFO to improve balance in non-neurologic impaired elderly patients. Rather, numerous peer-reviewed published studies have revealed the opposite treatment effect.3

While AFOs have significant potential benefit to treat neurologic deficits and musculoskeletal injury, practitioners should be aware of the potential shortcomings of these devices and take appropriate measures to minimize the negative effects on balance. Dispensing bilateral AFOs has been a rare practice in podiatric medicine and other specialties.4 The most common pathologies for which podiatric physicians prescribe AFOs — adult-acquired flatfoot, dropfoot, and degenerative joint disease of the ankle and hindfoot — present unilaterally in most cases. As Panwalkar and Aruin point out, there is little need to brace the contralateral limb for the most common musculoskeletal conditions and this practice will only further compromise balance.1

Studies have shown that articulated devices are less likely to have negative effects on balance.3 Articulated AFOs preserve ankle motion and are less likely to inhibit the important proprioceptive input from the ankle joint mechanoreceptors and feedback from the muscle/tendon stretch receptors in the leg. If practitioners prescribe non-articulated devices, they should consider dispensing a cane to improve stability and provide proprioception from the hand. Research has shown the use of a cane improves balance significantly when there is preexisting compromise.5

References
1. Panwalkar N, Aruin AS. Role of ankle foot orthoses in the outcome of clinical tests of balance. Disabil Rehabil Assist Technol. 2012 Oct 19. [Epub ahead of print]
2. 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.
3. 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.
4. Rubin G, Cohen E. Prostheses and orthoses for the foot and ankle. Clin Podiatr Med Surg. 1988; 5(3):695-719.
5. Richardson JK, Aston-Miller JA. Peripheral neuropathy. An often-overlooked cause of falls in the elderly. Postgraduate Medicine. 1996; 99(6):161-172.

Comments

I have been listening to both Dr. Richie and Dr. Moore speak on this subject for almost the last two years at state society APMA meetings and I did attend one AAPPM meeting last summer where Dr. Moore gave a presentation on balance risk assessment. I have also read both doctors blogs in Podiatry Today and Lower Extremity Review. In fact now that I think of this, I believe I listened to Dr. Richie speak on this subject for the first time two summers ago at the national APMA meeting in Boston.

Anyway, there is no question in my mind that Dr. Richie is more then convincing in every one of his presentations and blogs. The consistent peer reviewed studies and FACTUAL information that Dr. Richie talks about is OVERWHELMINGLY convincing that he is the true expert on this subject matter. In fact, a dear friend of mine who is a past president of The American Academy of Othotists and Prosthetists has told me that many of the Academy's fellows and members consult regularly with Dr. Richie about complex lower extremity cases.

Here is where I am confused. Please, somebody help me on this.

(I recently saw a) full page ad (in another publication) on the Moore Balance Brace by Safestep. Let me quote to you exactly what the ad states.
"The Moore Balance Brace (MBB) is a clinically proven treatment modality that effectively reduces trips and falls in elderly patients. The MBB Program will serve your elderly patients by broadening your practice scope and in doing so create an ETHICAL OPPORTUNITY FOR INCREMENTAL PRACTICE INCOME".

OK, I have a couple of questions. What is ethical here? Obviously nothing. The only fact is that it will increase practice income UNETHICALLY.

The Moore brace isn't what I would call "rigid," like a non articulated MAFO. What's the difference between semi-rigid and semi-flexible?

The studies discuss likelihood, not definitive conclusions.

Everyone has an opinion for sure but to outright say something is unethical is a stretch. Have you dispensed any of these devices in your office to determine how much they help the patient?

OK, so let's call the brace a cross between semi-rigid and semi-flexible. No big deal. The studies by Dr. Moore DO NOT discuss any likelihood or conclusions of anything pertinent to bilateral AFO bracing on the elderly. There are no studies. The studies he talks about are with patients with cerebral palsy and/or previous stroke or CVA.

Dr. Raducanu, if you speak with any orthopedic surgeon that specializes in the knee, they will tell you that you NEVER put bilateral OA and /or functional knee braces on the knee.

How come the Moore Balance Brace is not marketed to physical medicine and rehabilitation physicians and neurologists ? I will answer that question for you. They will laugh!

It is all about the revenue reimbursement in podiatry. Period !

If you have further questions on this subject matter, I strongly suggest you consult with the orthopedic foot and ankle specialists, podiatrists and the PM&R doctors at the Rothman Institute in Philadelphia.

And by the way, the Rothman Institute has their own orthotic department which is staffed by ABC certified orthotists.

Firstly, I spoke to the medical specialists in our area about the brace and they didn't laugh at all. They were intrigued. I will be discussing this more with them in the future.

Secondly, I hope you are kidding about Rothman. You and I can have a private conversation about how they do things and how many of their dehiscences I see at the WCC caused by all their "advanced techniques." Also, if you think they are any less concerned with the bottom line than everyone in medicine is at this point, you would be sorely mistaken.

@Doug: Let's you and I collaborate on a study to prove your theory and disprove mine, however frivolous you think it may be.

Those physicians that were intrigued were not PM&R physicians or neurologists. They may have been one or two of your podiatric colleages. No doubt !

I WAS NOT kidding about Rothman. I also DO NOT kidd about 3-B Orthopedics at Aria Health.

I can assure you that patients are not winding up at the Nazareth Wound Care Center, because of Rothman dehiscences. However, Nazareth is thrilled to have them bring cases to their hospital because they bring in MAJOR revenue.

I do agree with you that everyone is concerned more then ever about their bottom line.

They were several PM&R physicians and neurologists who were intrigued. You know what happens when you assume.

I work at the WCC at Naz. I am the one seeing these patients, sir. You know better though, right?

What does them bringing cases to Nazareth and making them money have anything to do with this discussion?

Hi Ron,

This will be my last response to you in reference to bilateral balance braces. First, I have a question for you. Are you by any chance a member of the AAPPM? The reason I ask you this is because the AAPPM is the only podiatric organization that endorses bilateral bracing to prevent falls.

I know you never discussed balance braces with any PM&R physicians or neurologists. Please understand that I was not born yesterday. As I said, I have no doubt you may have discussed this with one or two podiatric colleages, or perhaps the DPMs who you are employed by.

The reason I mentioned Nazareth Hospital is because I knew you see patients there. Why else do you think I mentioned Nazareth?

Apparently, the Rothman Institute and the revenue they bring in to Nazareth Hospital hits a sore spot. Sorry about that.

Now, I think it is only fair to tell you who I am. I am an orthopedic total joint rep and my main area of focus is knees and hips. I also have a few lines of hardware for the foot and ankle and circular frames.

For the foot and ankle products, I work with orthopedic foot and ankle surgeons and DPMs who are board certified in reconstructive rearfoot and ankle (RRA). My manufacturer requires the DPMs to be certified in (RRA) before they will even consider certifying them.

I wish you the very best of luck in your podiatric career in the Philadelphia region.

Ron,

I have heard these arguments before and they are frivolous. Comparing articulated vs non-articulated is plain and simple. Arguing whether a certain non-articulated shell AFO is more "flexible" than another does not in any way prove that it does not have the shortcomings of a more rigid device. If the AFO does not allow full motion of the ankle joint complex, it will inhibit proprioception and balance control. Until the makers of the "flexible" non-articulated AFO devices can prove their claims, all practitioners should be cautious, based upon the wealth of peer-reviewed scientific evidence which warns of the problems with these devices.

Ron, I am not proposing any theory. I am simply reporting scientific facts which are documented in the medical literature. Now, if you have a theory that these facts are wrong, please go into the laboratory and prove that a flexible shell AFO behaves the same as an articulated AFO.

While you are at it, please prove that prescribing bilateral solid shell AFOs will prevent falls in non-neurologic impaired elderly patients. Until then, please clarify that your endorsement of this practice is based purely on speculation and remains contradicted by sound science.

I'm working on something just like that, actually.

I don't remember saying anything about the benefits or lack thereof of the bilateral AFO in those patients. I will also be working toward something like that literature-wise as well. Stay tuned as I'm sure you'll have much to discuss about it.

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