Forefoot plantar pressure reduction of off-the-shelf rocker bottom provisional footwear.

Background: Increased plantar pressures have been shown to be a risk factor in ulceration of the neuropathic foot. Prescriptive footwear is a common medical treatment, yet evidence regarding the efficacy of these prescriptions is underdeveloped. The purpose of this study is to determine the off-loading properties of four provisional shoes; a rocker sole compared to a flat sole shoe with and without the addition of a 1.25 cm plastizote insert.

Methods: Fifteen subjects with peripheral neuropathy and a normal longitudinal arch were recruited to compare four types of provisional (post-operative) footwear. Plantar surface foot pressures were measured while wearing a rocker sole shoe or a flat stiff sole shoe. Both shoes were worn with and without a 1.25 cm plastizote insert. Peak plantar pressures were recorded for the hallux, metatarsal heads (1-5), midfoot, and heel.

Findings: The rocker sole shoe with plastizote had the best off-loading properties. While wearing this footwear, mean peak plantar pressure was 2.8 kg/cm(2) (range: 1.7 to 4.5 kg/cm(2), 50% mean reduction from flat sole shoe without plastizote) and 1.9 kg/cm(2) (range: 0.7 to 3.6 kg/cm(2), 35% mean reduction) at the five metatarsal heads and hallux, respectively.

Interpretation: For patients with a normal longitudinal arch and forefeet, either at risk of developing an ulcer or are healing a forefoot ulcer, a provisional shoe with a rocker sole and plastizote insole provides plantar pressure reduction of the forefoot. However, when results were analyzed for the subjects individually the amount of off-loading varied.