Data‐driven directions for effective footwear provision for the high‐risk diabetic foot

Aims Custom-made footwear is used to offload the diabetic foot to prevent plantar foot ulcers. This prospective study evaluates the offloading effects of modifying custom-made footwear and aims to provide data-driven directions for the provision of effectively offloading footwear in clinical practice. Methods Eighty-five people with diabetic neuropathy and a recently healed plantar foot ulcer, who participated in a clinical trial on footwear effectiveness, had their custom-made footwear evaluated with in-shoe plantar pressure measurements at three-monthly intervals. Footwear was modified when peak pressure was ≥ 200 kPa. The effect of single and combined footwear modifications on in-shoe peak pressure at these high-pressure target locations was assessed. Results All footwear modifications significantly reduced peak pressure at the target locations compared with pre-modification levels (range –6.7% to –24.0%, P < 0.001). The metatarsal heads were most frequently targeted. Repositioning an existing (trans-)metatarsal pad in the shoe insole (–15.9% peak pressure relief), applying local cushioning to the insole (–15.0%) and replacing the insole top cover with Plastazote (–14.2%) were the most effective single modifications. Combining a new Plastazote top cover with a trans-metatarsal bar (–24.0% peak pressure relief) or with local cushioning (–22.0%) were the most effective combined modifications. Conclusions In people with diabetic neuropathy and a recently healed plantar foot ulcer, significant offloading can be achieved at high-risk foot regions by modifying custom-made footwear. These results provide data-driven directions for the design and evaluation of custom-made footwear for high-risk people with diabetes, and essentially mean that each shoe prescribed should incorporate those design features that effectively offload the foot.