Sep-10

Can DPMs Have An Impact On The Multidisciplinary Team For Patients With Diabetes?

By Brian McCurdy, Senior Editor

When treating at-risk patients with diabetes, a multidisciplinary team can be invaluable in averting complications such as lower extremity amputation. A recent study in the Journal of the American Podiatric Medical Association says early identification and referral to a podiatric limb preservation team can improve the survival rate of at-risk patients with diabetes.

   In a retrospective cohort study involving 485 patients with diabetes, researchers collected data on ulcer status and surgical outcomes for five years in patients who received specialty podiatric medical care (311 patients) and those who did not (174 patients).

   The study found the proportion of “minor” amputations was significantly higher in the group receiving advanced multidisciplinary podiatric care (67.3 percent) versus the group that did not receive advanced multidisciplinary podiatric care (33.7 percent). Additionally, authors noted that during the study, 19.5 percent of non-specialty care patients died in comparison with 7.7 percent of patients in the podiatric limb preservation group.

   The study authors conclude that decreased rates of proximal amputations and increased rates of survival may result in patients with diabetes when there is early identification of those at risk for ulcerations and subsequent referral to advanced multidisciplinary podiatric medical specialty care.

Educating Patients On The Importance Of Foot Screenings

The most effective method of preventing ulcerations and amputations is a careful and frequent inspection of the diabetic foot, according to lead study author Vickie Driver, DPM, MS. She says one should assess and document abnormalities, whether they are age-related, structural or pathological.

   Dr. Driver cites the American Diabetes Association’s 2004 recommendation that patients with diabetes undergo a comprehensive annual foot examination, including a patient history. Dr. Driver and Peter Blume, DPM, cite the importance of the Semmes Weinstein 5.07 monofilament to test for diabetic neuropathy and palpating for pedal pulses.

   If patients do not have pedal complications of diabetes, annual screenings are sufficient, according to Dr. Blume, an Assistant Clinical Professor of Surgery in the Anesthesia and Orthopedics and Rehabilitation Department at the Yale School of Medicine. However, if patients do have disease affecting the foot, Dr. Blume says routine foot care is “extremely important” every two to three months along with offloading, education and strict glucose control.

   Dr. Driver supports giving patients specific instruction on foot care as well as insights on selecting proper footwear and breaking in shoes in order to help prevent blisters and ulcers.

    “It is imperative that patients understand the importance of daily foot exams, the implication of losing their protective sensation and proper foot care,” notes Dr. Driver, an Associate Professor of Surgery and the Director of Clinical Research, Foot Care at the Boston University School of Medicine.

Emphasizing The Role Of DPMs

In addition, Dr. Driver emphasizes that DPMs should spread the word to primary care physicians about their efficacy in treating high-risk patients with diabetes.

    “The data now shows that we are cost effective providers to help treat these patients,” maintains Dr. Driver, a Fellow of the American College of Foot and Ankle Surgeons. “We need to present at medical meetings where PCPs attend. This will help them understand how and when to consult us.”

Study Says Toning Shoes Don’t Live Up To The Hype

By Brian McCurdy, Senior Editor

Frequently aired TV commercials have familiarized millions of patients with toning shoes, which tout the benefits of a rocker bottom sole and cushioning. However, a new study sponsored by the American Council on Exercise is skeptical about the benefits of the shoes.

   Researchers compared 12 patients walking in a traditional walking shoe with 12 patients walking in Shape-ups (Skechers), MBT shoes (Masai Barefoot Technology) and EasyTone (Reebok). Patients walked at various speeds and grades on a treadmill for five minutes. Researchers used electromyography (EMG) to evaluate muscle activity in the gastrocnemius, rectus femoris, biceps femoris, gluteus maximus, erector spinae and rectus abdominus.

   None of the studied brands of toning shoes exhibited statistically significant increases in exercise response or muscle activation, according to the study authors. The researchers conclude there is “simply no evidence” in their study that the shoes aid in more intense exercise, help the shoe wearers burn more calories or improve muscle strength and tone.

Which Patients Would Benefit From Toning Shoes?

Kevin Kirby, DPM, has had varied experiences with toning shoes.

    “Some patients have reduced pain in their feet with these shoes and seem to be able to walk more comfortably, and other patients who purchase these shoes cannot wear them for very long due to an increase in foot, knee and leg pain,” notes Dr. Kirby, an Adjunct Associate Professor within the Department of Applied Biomechanics at the California School of Podiatric Medicine at Samuel Merritt University in Oakland, Calif.

   After wearing toning shoes and examining their construction, Dr. Kirby says the variance in patient comfort may be due to a wide variation in shoe design but more likely is due to differences in the structure of patients’ feet, their biomechanics and the anatomic location of foot pain.

   Due to the rocker bottom sole, Dr. Kirby may recommend toning shoes for conservative care of painful hallux limitus, hallux rigidus and metatarsalgia. Due to their soft rearfoot midsole wedges, he may also recommend the shoes for those with chronic proximal plantar fasciitis. However, Dr. Kirby does not recommend the shoes as an initial conservative treatment since he cannot yet predict which patients will respond to the shoes, be able to wear them comfortably and not develop leg or knee pain. Dr. Kirby only recommends toning shoes for those who have failed basic conservative treatment of their foot and/or lower extremity pathology with strapping, padding, foot orthoses and more traditional styles of shoes.

   Patrick DeHeer, DPM, does not think any patients would benefit from toning shoes. In his opinion, some of the marketing claims of the shoe companies are “false advertising” and the shoes may worsen equinus. For patients who do want to improve tone and posture, Dr. DeHeer, the team podiatrist for the Indiana Pacers and Indiana Fever, recommends a good running shoe or cross-trainer.

   For patients who want to tone legs and buttocks as well as improve posture, Dr. Kirby would not recommend toning shoes since research has not shown toning shoes are any more effective than other shoes at increasing muscle function or changing body shape. To tone legs, he suggests patients eat less, eat healthier and perform a balanced exercise program in traditional athletic shoes.

Assessing The Impact Of Standing In Patients With Diabetic Neuropathy

By Brian McCurdy, Senior Editor

Patients with diabetic neuropathy may have a tendency not to consider standing as physical activity. A poster presented at the recent American Podiatric Medical Association (APMA) Annual Scientific Conference shows that walking may cover just 3 to 13 percent of the activities of patients with neuropathy and may not be an accurate picture of what patients are doing with their day.

   Researchers focused on 13 patients with diabetic peripheral neuropathy who wore a sensor for 48 hours. The sensor extracted data on posture and locomotion. The authors found that patients spent approximately 13 percent of their time standing and 6 percent walking. Approximately 37 percent of the patients’ time was spent sitting and 44 percent of the patients’ time was spent lying down. Patients took an average of 7,754 steps a day and had an average of 357 walking episodes a day, with a maximum duration of 3.9 minutes, according to the study, which is also scheduled to be published in Diabetes Care.

   The study authors note that the literature does not take standing posture into account when considering diabetic neuropathy and suggest that further research into the topic is warranted. The profession is just starting to educate patients about time spent standing, says abstract author Bijan Najafi, PhD. As he notes, since cumulative stress is “very important” while patients are standing, patients should be educated on this accordingly.

   Given that many patients do not believe they need to offload the foot while standing, Dr. Najafi says patients must learn to wear offloading or surgical shoes while standing and walking. As he notes, a long period of standing may be deleterious for patients with diabetes and suggests further study into that hypothesis.

   Patients with diabetic neuropathy need to pay more attention to the physical activity they undertake at home, according to Dr. Najafi, who is affiliated with the Center for Lower Extremity Ambulatory Research (CLEAR) at the Scholl College of Podiatric Medicine at the Rosalind Franklin University of Medicine and Science in Chicago. He cites a strong tendency of patients to associate only moderate to intense bouts of activity with physical activity. He also stresses the importance of consistency in physical activity, noting that research has shown variability in activity to be a better predictor of ulcers than the volume of physical activity.

How Effective Are Shear Reducing Insoles?

By Brian McCurdy, Senior Editor

A number of insoles have emerged recently with the aim of reducing shear forces under the foot for patients with diabetes. Researchers recently tested the biomechanical efficacy of two insoles designed to reduce shear.

   The study, presented as a poster at the APMA Annual Scientific Conference, focused on 18 people who walked along a 100-foot line while wearing three different types of insoles. The insoles were the Vasyli Armstrong Diabetic Orthotic (Vasyli Medical) and the Spenco RX Diabetic Support Foot Beds (Spenco Medical). Generic EVA insoles were the control footwear.

   Researchers found no significant differences in step length among the two insoles and control insole. Since the study did not show a decrease in step length in patients wearing the diabetic insoles, the authors concluded that shear reducing diabetic insoles do not function under in vivo or in vitro conditions.

   There are basically two approaches to reduce plantar shear: reducing the peak shear stress and reducing the net shear force under the foot, according to the study abstract co-author Metin Yavuz, PhD, an Assistant Professor in the Department of Basic Sciences at the Ohio College of Podiatric Medicine.

   When lowering the peak shear stress is a concern, he says one may think that a full contact orthotic may help by increasing the effective load bearing area under the foot. However, Dr. Yavuz cites Ahmet Erdemir, PhD, who stated that “insole solutions to distribute plantar pressures may not necessarily have the same effect on contact shear” (see “Can Smart Orthotics Have An Impact In Preventing Ulceration?” in the June 2010 issue of Podiatry Today or https://tinyurl.com/24c8vbm).

   Dr. Yavuz says that although one of the orthotics in his study tries to reduce net frictional shear force under the foot by allowing a limited slippage between the layers of the product, the design, though innovative, has shortcomings. If the orthotics really worked as intended, he says one would see reduced step lengths.

   While it may be possible to decrease the net shear force (in particular fore-aft shear), Dr. Yavuz says this will come at the expense of increasing the number of steps to traverse a certain distance. He notes step length and fore-aft shear are strongly associated: the higher the amount of fore-aft shear, the longer the step. Since ulceration occurs due to “repetitive moderate stresses,” he says reducing stress while increasing the number of repetitions may not be beneficial at all.

   Dr. Yavuz says the late Paul Brand, FRCS, suggested a mechanism to permit patients with diabetes to take shorter steps, which should reduce net shear force under the foot and vertical impact forces. However, to the best of his knowledge, Dr. Yavuz says there is not much evidence that this idea would work.