Custom-made footwear in diabetes: Offloading, usability and ulcer recurrence

Foot ulceration is a serious long term complication in patients with diabetes mellitus and polyneuropathy, which increases the risk of infection and lower limb amputation. Loss of protective sensation and high levels of plantar foot pressure during ambulation are the main causative factors. These patients are often prescribed with custom-made therapeutic footwear, which aims to offload high-risk plantar foot sites through pressure redistribution, however, scientific evidence for its use is meagre. It was therefore aimed to expand the knowledge on the effectiveness of custom-made footwear for diabetic patients at high risk of foot ulceration, with respect to offloading and ulcer prevention. Offloading efficacy of custom-made therapeutic footwear was often found insufficient and required improvement, which could be achieved and maintained by modifying footwear guided by in-shoe plantar pressure assessment. This thesis provided data-driven directions for effective footwear modification to reduce plantar pressure. A randomized controlled trial, the DIAFOS trial, showed that offloading-improved custom-made footwear did not significantly reduce foot ulcer recurrence rate when compared to usual care, unless adherence to footwear use was assured. It was furthermore shown that adherence to footwear was particularly low in patients who perceived low benefit of using custom-made footwear. The findings suggest that adequate offloading as well as footwear adherence have to be assured to effectively prevent foot ulcer recurrence in diabetic patients with neuropathy and previous foot ulceration. The described implications for clinical practice and recommendations for further research may improve outcomes in diabetic patients who are at high risk of ulcer recurrence