A proof-of-concept study of the effectiveness of a removable device for offloading in patients with neuropathic ulceration of the foot: the Ransart boot

Aim To undertake a proof-of-concept study to determine whether a removable offloading device (the Ransart boot) for the management of diabetic foot ulcers (DFU) was as effective as reports of non-removable devices. Research design and methods This observational study used the Ransart boot for patients with DFU, in seven specialist centres. If a patient had two or more ulcers, one was selected as the index ulcer. Ulcers were classified by the University of Texas (UT) system. Results There were 135 patients (mean age 60.3 +/- 11.4 years); 96 (71.1%) male. Median ulcer duration at presentation was 90 [interquartile range (IQR) 30-1825] days. Seven were lost to follow-up, seven developed other major illnesses and four died; outcomes were documented in the remaining 117. Eighty-two (70.1% of 117) healed, after a median (IQR) 60 (43-99) days, while 22 (18.8%) ulcers were resolved by amputation (one major). The remaining 13 (11.1%) patients were judged non-compliant. There was a close correlation between ulcer classification at baseline and both time to healing (P < 0.001 KH2-test) and amputation (P < 0.001; Spearman's rank correlation coefficient). There was a positive correlation between ulcer duration at presentation and time to healing (P < 0.02), UT class (P < 0.01), glycated haemoglobin (P < 0.02) and amputation (P < 0.04). Conclusions Time to healing and incidence of amputation were comparable with those previously reported for non-removable devices. Given that a removable device is much more acceptable to the patient, the effectiveness, cost and acceptability of the removable devices, such as the Ransart boot, need to be compared with a non-removable device in a randomized trial.