Treatment of chronic plantar ulcer of the diabetic foot using an irremovable windowed fibreglass cast boot: prospective study of 177 patients.

The objective of this study was to evaluate the level of healing of chronic neuropathic plantar ulcers, using an irremovable windowed fibreglass cast boot, which is only opened after healing. A single-centre prospective study of a cohort of 177 diabetic patients with chronic neuropathic plantar ulcers was carried out. The duration of neuropathic plantar ulcers was 604 ± 808 days, with a mean surface area of 4.6 ± 6.5 cm(2) , a mean depth of 1.04 ± 1.08 cm and a mean volume of 5.9 ± 17.7 cm(3) . After a mean of 96 days of wearing a windowed fibreglass cast boot (min 9 days, max 664 days and median 68 days), the level of healing reached 83.6%, although 29 patients did not heal (16.4%). The compliance was at 95%. NPUs with bigger volumes (p = 0.037) and those located at the heels ( p = 0.004) had significantly lower healing levels. Twenty-one patients had moderate peripheral arterial disease (12%), and 24 patients were ostectomized for underlying osteomyelitis (14%), before inclusion. Moderate peripheral arterial disease (p = 0.970) or operated osteomyelitis (p = 0.128) did not modify the level of healing significantly, which were of 81% and 70.8%, respectively. Complications include 12 ulcers due to the windowed fibreglass cast boot (i.e. 7%) and two other ulcers being moderately infected, resulting in 2% of toe amputation, but there was no major amputation or phlebitis. The treatment of old and deep NPUs of the diabetic foot by wearing a windowed fibreglass cast boot without opening the boot prior to healing offers very high ulcer recovery levels. Windowed fibreglass cast boots were changed in only 26 cases (14.6%). In addition, compliance was excellent and of the order of 95%. Furthermore, moderate peripheral arterial disease or a recent ostectomy did not affect the efficacy of windowed fibreglass cast boot.