Oral session 1: Offloading
O1.1
The effect of felted foam on plantar peak pressure relief and it’s preservation over
time
Tessa Busch-Westbroek, Academic Medical Centre, Amsterdam, Netherlands
Laurens Holst, Vrije Universiteit, Amsterdam, Netherlands
Han Houdijk, Vrije Universiteit, Amsterdam, Netherlands
Sicco Bus, Academic Medical Center, Amsterdam, Netherlands
Aim: Plantar foot ulcers are usually the result of high plantar pressures in combination with
reduced sensibility and foot deformities. Offloading interventions are commonly used to
lower the pressure at ulcer locations to promote healing1 2. Felted foam is a commonly used
adjuvant therapy to relieve the pressure and heal plantar foot ulcers3. However, the
evidence for its offloading effect is limited.4 5 The aim of this study is to assess the effect of
different commonly used felted foams on peak plantar pressure relief and preservation over
time.
Methods: Sixteen healthy adult subjects participated in the study. First, a cross-sectional
study was performed to study the pressure-relieving effect at the central metatarsal heads of
six different types of felted foam. We used Hapla Swan foam, Hapla Foam-o-felt, Hapla
Mixture felt, Hapla Semi-compressed felt, Hapla Poron and Cellona padding felt. Each was
available in a 5 and 10mm thickness, that were attached to the plantar forefoot and
assessed with the subject walking across an EMED-X pressure platform. An aperture was
cut in each felted foam that represented the region of interest. In a subsequent longitudinal
study, three selected types of 5-mm thick felted foam were randomly attached under the feet
and worn for 3 consecutive days. Peak pressures were measured with the EMED-X after
24h, 48h, and 72h.
Results: All tested types and thicknesses of felted foam significantly reduced peak
pressures, compared to walking barefoot without felted foam. Mean peak pressure
reductions varied between 31 5 % and 42 6 % across foams. Over time there was a
tendency of increased peak pressures with 17-22% after 24h and small increases (<5%)
after that. However pressure increase compared to baseline was significant in only one foam
at 72h.
Conclusions: Felted foam is effective in relieving peak plantar pressure in the forefoot of
healthy individuals. There is no reason to believe that outcomes would be different in
diabetic patients. The felted foam loses its offloading effect over time, most notably in the
first 24 hours of wearing and thus requires frequent replacement, preferably every day.
Felted foam seems to be a useful adjuvant therapy to offload the foot
www.diabeticfoot.nl
Page 1 of 5
O1.2
Footwear for diabetic patients with peripheral neuropathy: Impact of a rocker sole on
balance
Hanna McShane, Aktiv ortopedteknik, Lund, Sweden
Magnus Londahl, Skane University Hospital, Lund, Sweden
Nerrolyn Ramstad, Jönköping University, Jönköping, Sweden
Aim: Shoes with rocker profiles reduce plantar pressure in people with diabetes and
peripheral neuropathy. These patients however suffer from impaired balance and an
increased risk of falls. The extent to which rocker profile shoes affect balance is currently
unclear.The aim of this study was to investigate the effects of a standardised rigid forefoot
rocker on balance and gait in people with diabetes and peripheral neuropathy.
Methods: Nineteen patients with diabetes and peripheral neuropathy participated. Patients
were assessed wearing footwear with a rigid forefoot rocker (test shoe) and wearing
standard orthopaedic footwear (control shoe)., Three tests, all correlated to fall risk, were
performed. These were, standing balance, timed up and go test, and temporo-spatial
parameters of gait.
Results: A significant difference was observed in medio-lateral Sway when subjects were
standing with their feet together (p<0.05). The test shoe condition resulted in a reduced
range of COP displacement. When walking on level ground the test shoe resulted in a
significantly longer duration in single limb stance (p<0 05). No difference was observed in
the timed up and go test.
Conclusions: Rigid forefoot rocker shoes do not disturb balance in people with diabetes and
peripheral neuropathy and are unlikely to increase the risk of falling.
www.diabeticfoot.nl
Page 2 of 5
O1.3
The efficacy of removable devices to offload and heal neuropathic plantar forefoot
ulcers in diabetes: a randomized controlled trial
Jaap van Netten, Ziekenhuisgroep Twente, Almelo, Netherlands
Jeff van Baal, Ziekenhuisgroep Twente, Almelo, Netherlands
Anke Kottink, Ziekenhuisgroep Twente, Almelo, Netherlands
Erik Manning, Ziekenhuisgroep Twente, Almelo, Netherlands
Maximilian Spraul, Mathias Spital, Rheine, Germany
Arend Jan Woittiez, Ziekenhuisgroep Twente, Almelo, Netherlands
Sicco Bus, Academic Medical Center, Amsterdam, Netherlands
Background: Offloading is required to heal neuropathic plantar foot ulcers in diabetes.
While guidelines recommend non-removable offloading, removable offloading is more
commonly used, but little is known about its efficacy to offload the foot in combination with
healing plantar foot ulcers.
Aim: To investigate the efficacy of three removable offloading devices (bivalved total contact
cast, cast shoe, and a forefoot offloading shoe) on healing of neuropathic plantar forefoot
ulcer in patients with diabetes.
Method: We randomly assigned 60 diabetic patients with non-infected, non-ischemic
neuropathic plantar forefoot ulcers to a bivalved total contact cast (BTCC), cast shoe
(MABAL), or a forefoot offloading shoe (FOS). Patients were followed until healing or until 12
weeks (primary) and 20 weeks (secondary). Dynamic peak pressure at the ulcer site in the
device and daily stride count were measured. Treatment adherence was assessed from
patient reports.
Results: According to intention-to-treat, 12-week healing percentages were 58% for BTCC,
60% for MABAL, and 70% for FOS (p = 0.70); 20-week healing percentages were 63%,
83%, and 80%, respectively (p = 0.31). Mean ± SD peak pressure in kPa at the ulcer site
was 81 ± 55 for BTCC, 176 ± 80 for MABAL, and 107 ± 52 for FOS (p = 0.005); mean ± SD
daily stride count was 4150 ± 1626, 3514 ± 1380, and 4447 ± 3190, respectively (p = 0.71).
Percentage of two-week intervals that patients wore the device <50% of time was 17.3% for
BTCC, 5.2% for MABAL, and 4.9% for FOS.
Conclusion : Clinical efficacy was not significantly different between removable devices and
was lower than previously found for non-removable offloading. Exposure to repetitive stress
by lack of forced adherence and high daily stride count, stresses the importance of
continuous pressure relief in healing neuropathic plantar foot ulcers in diabetes.
Acknowledgements: This study was funded from a project grant within the INTERREG IIIA
program for cross-border collaboration within the Euregio, of the European Union, project
number: 2-EUR-II-2=60.
www.diabeticfoot.nl
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O1.4
Randomized clinical trial to evaluate efficacy and safety between total contact casts,
removable cast boots and instant total contact casts
Lawrence Lavery, UT Southwestern Medical Center, Dallas, TX, United States
David Lavery, Statistical Consultant, Aurora, CO, United States
David Armstrong, University of Arizona, Tucson, AZ, United States
Douglas Murdoch, Baylor Scott and White Health System, Temple, TX, United States
Javier La Fontaine, UT Southwestern Medical Center, Dallas, TX, United States
Aim: The objective of this study is to compare clinical efficacy and safety of 3 off-loading
techniques in 247 patients with diabetic foot ulcers during a 20 weeks evaluation period.,
Methods: Patients were randomly assigned to three off-loading treatments: total contact
cast (TCC, n=86), instant total contact cast (ITCC, n=80) or removable cast boot (RCB,
n=81). Patients were excluded from the study if they had an ABI<0.5, if they had an
untreated infection, or if they could not safely use the cast or boot. Patients received
debridement ad liberty and local wound care. Every 7-10 days we obtained digital photos,
wound measurement and evaluated the ulcer for infection and complications.,
Results: There was no difference in age, sex, race or ABI’s among study groups.
Significantly more patients healed in the TCC group (TCC 74.4%, RCB 45.7%, ITCC 45.0%,
p<0.05). TCC had fewer iatrogenic ulcers, abrasions or blisters (TCC 18.6%, RCB 29.6%,
ITCC 16.3%, p<0.05), infections (TCC 5.8%, RCB 18.5%, ITCC 17.5%, p<0.05), and serious
adverse events (TCC 10.5%, RCB 22.5%, ITCC 25.4%, p<0.05) compared to other
treatments.
Conclusions: A higher proportion of diabetic foot ulcers healed in the group using Total
Contact Cast as off-loading technique and the complication rate was lower.
www.diabeticfoot.nl
Page 4 of 5
O1.5
Patient centric device design of smart insoles for real time monitoring of plantar
pressures
Bijan Najafi, University of Arizona, College of Medicine, Tucson, AZ, United States
Jacqueline Lee-Eng, University of Arizona, College of Medicine, Tucson, AZ, United States
Manish Bharara, University of Arizona, College of Medicine, Tucson, AZ, United States
David Armstrong, University of Arizona, College of Medicine, Tucson, AZ, United States
Aim: People with diabetic peripheral neuropathy (DPN) are at high risk for developing
diabetic foot ulcers (DFU)., We studied novel plantar insoles (Orpyx Medical Technologies
Inc. Canada) that offer real time plantar pressure monitoring and patient engagement via
wearable technology to self-direct offloading and/or physical activity behaviors.
Methods: We conducted two independent studies aimed to assess device feasibility,
acceptability, and perceived patient benefit. Twenty-one DPN patients with recently healed
ulcers (age: 61±12 years) were recruited in the first study to evaluate patient satisfaction via
device related questionnaire with Likert scale categorized into: 1) user-friendliness, 2)
perceived benefit, 3) frequency of usage, and 4) satisfaction experience. Additionally, we
assessed gait and balance pre & post insole fitting to objectively study biomechanical
changes. Second study is ongoing, with N=30 patients using a redesigned insole whose
design incorporated feedback from the first study.
Results: 57% of patients who completed the first study were satisfied and approved of the
device., Fourteen patients dropped out or did not complete the study due to device-related
concerns including insole thickness and using an iPod as feedback device. These insights
provided data points for the redesign of the insoles, which has resulted in changes including
reduced thickness and the inclusion of a smartwatch for the provision of real-time feedback.
Patient satisfaction improved and is currently > 80% for the ongoing second study,
significantly superior to the initial prototype (p<0.05). Adherence to intervention also
improved to greater than 4 hours per day compared to 1 hour in first study. Gait & balance
parameters indicate better level of comfort and safety during both standing and walking for
the improved device.
Conclusion: Our investigation provides patient reported satisfaction scores aimed at
improving device form factor and specific elements that enhance adherence for real time
monitoring of plantar pressures. Although more data supporting the efficacy of such
technology in the prevention of plantar ulcers is needed, no ulcers were observed during 3
months in our high-risk samples, which may indicate potential benefit of this technology.
www.diabeticfoot.nl
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