Comparisons of shoe-length and shoe-width fitness in people with diabetes, diabetes sensory neuropathy and non diabetes

Abstract

Introduction Ill-fitting footwear is one of the well-known risk factors causing foot ulceration in the diabetic population. Current literature for fitness of foot dimensions is insufficient, especially on foot-shoe length and foot-shoe width measurement in absolute numerical differences. The aims of the study were to compare and identify the footwear fitness in diabetic patients with peripheral sensory neuropathy, diabetic patients without peripheral neuropathy and non diabetes.

Materials and Method Diabetes patients were assessed for peripheral sensory neuropathy by two sensory tests, 10-g monofilament test using 10-g Semmes-Weinstein monofilament and vibration perception threshold test using neurotheisometer. Abnormal results of both tests indicated diabetes sensory neuropathy. The dimensions of foot length and foot width were determined by the Brannock device while internal shoe length and internal shoe width were measured by an inside caliper. The mean of internal shoe-length difference and shoe-width difference of three groups were calculated and compared. Reference ranges of 10-15mm of shoe-length difference and 0-7mm were selected from past literature. The values of shoe-length and shoe-width differences were dichotomized into correct and incorrect fit category. Footwear fitness of the three groups was compared. Demographics of patients, information on self foot care, shoe size check and footwear habit were collected for correlation analysis. Results Data was collected from 20 diabetes patients with sensory neuropathy, 60 diabetes patients without neuropathy and 40 non diabetes controls. There were significant difference in shoe-length difference among three groups, with larger shoe-length difference in diabetic neuropathy group (left: 21.9mm, / right: 21.7mm), followed by non neuropathy diabetes (left: 15.2mm, / right: 15.5mm) and controls (left: 13.4mm, / right: 14.5mm) (left p=0.002 / right p=0.008). The shoe-length differences of both diabetes groups exceeded the reference range, indicating long footwear. No significant difference was reported related to shoe-width difference. Analysis of shoe fit category showed around 15-17% of diabetes patients were wearing correctly fit shoes in both length and width. A high prevalence of diabetes patient had ill-fitting footwear while nearly half of them wear shoes with correct width but incorrect length. There is nearly no correlations between shoe-length fit, shoe-width fit and frequency of self foot check, frequency of footwear size check and frequency of diabetic footwear education.

Discussion Most diabetes patients wear ill-fitting footwear, especially those with peripheral sensory neuropathy when compared to control group. There is significant difference in shoe-length difference among the three groups, with reference to the 10-15mm range as the gap length allowance. Diabetic patients tend to wear long and loose footwear in this study even they had past foot education and practice proper self foot check regularly. These might imply incomprehensive proper diabetic footwear education and self footwear assessment in current diabetes care pathway. These components are essential in diabetes foot care and people with diabetes are highly recommended to select a pair of good fit footwear. Further research is required to standardize the methodologies of measurement in foot dimensions and footwear fitness as well as investigate on relations of additional foot parameters in shoe fitting.