Foot ulcer recurrence, plantar pressure and footwear adherence in people with diabetes and Charcot midfoot deformity: A cohort analysis

Aims: To investigate people with Charcot midfoot deformity with regard to plantar pressure, footwear adherence and plantar foot ulcer recurrence. Methods: Twenty people with diabetes, Charcot midfoot deformity, plantar foot ulcer history and custom-made footwear were assessed with regard to barefoot and in-shoe plantar pressures during walking, footwear adherence (% of daily steps over 7-day period) and plantar foot ulcer recurrence over 18 months. In a cohort design, they were compared to 118 people without Charcot foot (non-Charcot foot group) with custom-made footwear and similar ulcer risk factors. Results: Median (interquartile range) barefoot midfoot peak pressures were significantly higher in the Charcot foot group than in the non-Charcot foot group [756 (260–1267) vs 146 (100–208) kPa; P<0.001]. In-shoe midfoot peak pressures were not significantly higher in the Charcot foot group [median (interquartile range) 152 (104–201) vs 119 (94–160) kPa] and significantly lower for all other foot regions. Participants in the Charcot foot group were significantly more adherent, especially at home, than participants in the non-Charcot foot group [median (interquartile range) 94.4 (85.4–95.0)% vs. 64.3 (25.4–85.7)%; P=0.001]. Ulcers recurred in 40% of the Charcot foot group and in 47% of the non-Charcot foot group (P=0.63); midfoot ulcers recurred significantly more in the Charcot foot group (4/8) than in the non-Charcot foot group (1/55; P=0.001). Conclusions: Effective offloading and very high footwear adherence were found in people with diabetes and Charcot midfoot deformity. While this may help protect against plantar foot ulcer recurrence, a large proportion of such people still experience ulcer recurrence. Further improvements in adherence and custom-made footwear design may be required to improve clinical outcome.