○Hisae Hayashi1, Kenichi Kono2, Eriko Kondo3, Nobuhide Kawabe4
(1.Seijoh University, 2.Aichi medical college, 3.Nagoya Kyoritsu Hospital, 4.Chigasaki Rehabilitation College)
Keywords:off-loading, plantar pressure, ulcer recurrence
Purpose：Inadequate off-loading leads to plantar tissue damage and ulcer recurrence in diabetic patients. A postoperative shoe with a plug-removed insole（PRI）is commonly used for off-loading of the region. However, regional plantar pressure is generally not measured in a clinical setting, although there is some debate over whether PRI results show substantial relief in pressure beneath the first-metatarsal-heads（1MTH）. The purpose of this study is to evaluate the efficacy of off-loading of 1MTH using postoperative shoes with PRIs. Methods：The 1MTH plantar pressure during walking was measured in participants（9 males and 4 females：mean age 72±6 years）, none of whom had severe foot deformities, a plantar ulcer or previous minor amputation. The subjects walked a 10 m distance 3 times at their preferred speed using postoperative shoes with 3 different kinds of insoles：flat cork board（control-condition：CC）, plugged insole（PI）and PRI. The plantar pressure of 1MTH was continuously recorded at 200 Hz during walking, using a piezoelectric pad sensor. Substantial off-loading was defined as a greater than 25% reduction in the peak pressure（Bus SA, 2011）of 1MTH.
Results：Three out of fifteen participants achieved ＞25% reduction in peak pressure of 1MTH using a PI or PRI. The median values[interquartile range]（N/kg）of CC, PR and PRI were 1.64[0.12-3.49], 1.95[0.46-4.9]and 2.28[0.54-3.87], respectively.
Discussion：Results of this study show that PIs and PRIs have limited efficacy in pressure reduction in the elderly. The study suggests the off-loading efficacy of these insoles may vary with the individual；in a clinical setting, the likelihood of the patient’s benefiting from a particular insole can be ascertained prior to providing physical therapy. Such advance evaluation might help physical therapists choose appropriate insoles and potentially reduce the recurrence of foot ulcers.
