Plantar pressure changes using a novel negative pressure wound therapy technique

This study evaluated changes in pressure imparted to diabetic foot wounds using a novel negative pressure bridging technique coupled with a robust removable cast walker. Ten patients had plantar pressures assessed with and without a bridged negative pressure dressing on the foot. Off-loading was accomplished with a pressure-relief walker. Plantar pressures were recorded using two pressure-measurement systems. The location and value of peak focal pressure (taken from six midgait steps) were recorded at the site of ulceration. Paired analysis revealed a large difference (mean ± SD, 74.6% ± 6.0%) between baseline barefoot pressure and pressure within the pressure-relief walker (mean ± SD, 939.1 ± 195.1 versus 235.7 ± 66.1 kPa). There was a mean ± SD 9.9% ± 5.6% higher pressure in the combination device compared with the pressure-relief walker alone (mean ± SD, 258.0 ± 69.7 versus 235.7 ± 66.1 kPa). This difference was only 2% of the initial barefoot pressure imparted to the wound. A modified negative pressure dressing coupled with a robust removable cast walker may not impart undue additional stress to the plantar aspect of the foot and may allow patients to retain some degree of freedom (and a potentially reduced length of hospital stay) while still allowing for the beneficial effects of negative pressure wound therapy and sufficient off-loading.