Measurement of plantar pressure differences in the contralateral limb when using offloading modalities for diabetic foot ulcerations

Background: This study investigated the effect of various offloading devices commonly used for the management of diabetic foot ulcerations on peak plantar pressure and pressure-time integral of the contralateral limb.

Methods: A quantitative, randomised and within-subject repeated measures study was conducted in an outpatient gait laboratory. Outpatients with unilateral diabetic foot ulcers and adequate perfusion to the lower limb without an intrinsic limb-length discrepancy who were able to walk were recruited for the study. They were also required to understand English. An in-shoe pressure sensor was placed in the participants' everyday shoes between their feet and insoles. Participants were asked to walk at their own speed and cadences with three stances recorded. Their peak and mean plantar pressures were recorded. This was repeated with four different offloading conditions: Darco APB™ All Purpose Boot, Darco APB™ All Purpose Boot with wool felt adhered to the bottom of the foot, DH Offloading Walker® and DH Offloading Walker® with Even-Up™ on the contralateral foot.

Results: The total sample comprised 22 adults (3 females and 19 males) aged between 34 and 78 years old (mean age, 57.6 ± 9.9 years). The results indicated that none of the regions of the foot showed a statistically significant difference in peak plantar pressure and pressure-time integral between the control condition and other offloading modalities, or between modalities.

Conclusion: The use of offloading modalities for diabetic foot ulcers does not significantly affect peak plantar pressure or pressure-time integral measures on the contralateral limb. However, this should be considered with caution, as this population will possess the same risk factors in both the affected and the contralateral foot.