Offloading effect of therapeutic footwear in patients with diabetic neuropathy at high risk for plantar foot ulceration.
OBJECTIVE
Custom-made therapeutic footwear is often prescribed to patients with diabetic neuropathy, foot deformity and a healed plantar foot ulcer. Offloading these feet is important to prevent ulcer recurrence. The aim was to evaluate the offloading effect of custom-made footwear in these patients.


METHODS
In 171 patients with diabetic neuropathy (336 feet) with foot deformity and a recently healed plantar foot ulcer, plantar pressures walking barefoot and inside new custom-made footwear were measured. At the previous ulcer location and at locations of highest barefoot pressure attributable to the deformity, in-shoe pressures were compared with non-deformed feet. The footwear was considered effective in offloading when in-shoe peak pressure at these locations was < 200 kPa.


RESULTS
Mean in-shoe peak pressures ranged between 211 and 308 kPa in feet with forefoot deformity (vs. 191-222 kPa in non-deformed feet) and between 140 and 187 kPa in feet with midfoot deformity (vs. 112 kPa in non-deformed feet). Offloading was effective in 61% of all feet with deformity, 81% of feet with midfoot deformity, 44% of feet with forefoot deformity and 62% of previous ulcer locations. Inter-subject variability in measured in-shoe plantar pressure was large.


CONCLUSIONS
Offloading in custom-made footwear is often not sufficiently achieved in high-risk diabetic feet with deformity. Highest offloading success rates were seen at known high-risk locations such as previous ulcer locations and Charcot feet, the lowest success rates in forefoot deformities. Together with the large inter-subject variability in pressure outcomes, this emphasizes the need for evidence-based prescription and evaluation procedures to assure adequate offloading.
Department of Rehabilitation, University of Amsterdam, Amsterdam, The Netherlands. m.l.arts@amc.uva.nl
M L J
ML
Arts
R
R
Waaijman
M
M
de Haart
R
R
Keukenkamp
F
F
Nollet
S A
SA
Bus
D015992:Body Mass Index; D003922:Diabetes Mellitus, Type 1 / Q000150:complications / Q000503:physiopathology* / Q000534:rehabilitation; D003924:Diabetes Mellitus, Type 2 / Q000150:complications / Q000503:physiopathology* / Q000534:rehabilitation; D017719:Diabetic Foot / Q000503:physiopathology* / Q000534:rehabilitation; D005260:Female; D005530:Foot Deformities / Q000503:physiopathology* / Q000534:rehabilitation; D006442:Glycated Hemoglobin; D006801:Humans; D008297:Male; D008875:Middle Aged; D009989:Orthotic Devices; D010146:Pain; D011312:Pressure; D012008:Recurrence; D012775:Shoes; D016138:Walking
D006442:Glycated Hemoglobin; C517652:hemoglobin A1c protein, human