Pressure offloading is one of the most consistently supported interventions in the management of diabetic foot ulcers (DFUs). Repetitive mechanical stress under an insensate, biomechanically altered foot is a principal driver of tissue breakdown in patients with diabetic peripheral neuropathy. Without effective redistribution of plantar pressure, even optimal wound care, glycemic control, and infection management struggle to produce timely healing. The 2023 update of the International Working Group on the Diabetic Foot (IWGDF) guideline reinforces this principle and offers a clear, evidence-graded hierarchy of offloading strategies.
The Evidence-Based Hierarchy of Offloading
The 2023 IWGDF offloading guideline, developed by Bus and colleagues using the GRADE framework, recommends a non-removable knee-high offloading device as the first-line intervention for a neuropathic plantar forefoot or midfoot ulcer. The two acceptable forms are a total contact cast (TCC) or a removable walker rendered irremovable, typically by wrapping it with a fiberglass or cohesive overlay. When a non-removable device is contraindicated — for example because of significant ischemia, active infection requiring frequent inspection, or patient intolerance — a removable knee-high or ankle-high device is the second choice. Appropriately fitting footwear combined with felted foam is reserved for situations where no offloading device is available.
How Total Contact Casting Compares to Removable Alternatives
The biomechanical advantage of the total contact cast is well documented. Non-removable knee-high devices have been shown to reduce forefoot peak plantar pressure by up to roughly 87% relative to control conditions, and they eliminate the principal failure mode of removable devices — the patient simply taking them off.
A 2023 systematic review and meta-analysis in Frontiers in Endocrinology by Chen and colleagues pooled twelve studies covering 591 patients. Compared with removable walkers and therapeutic footwear, the TCC group had higher healing rates (relative risk 1.22; 95% CI 1.11 to 1.34; p<0.001) and shorter mean time to closure. TCCs outperformed both removable walking casts (RR 1.20) and footwear (RR 1.25). Device-related complications such as superficial skin irritation were more common with TCCs than with footwear but did not differ significantly from removable walkers. These findings are consistent with the meta-analysis by Lazzarini and colleagues that informed the IWGDF 2023 update.
Adherence: The Determining Factor in the Real World
Despite the favourable pressure-reducing properties of removable devices in laboratory studies, adherence in daily life is consistently poor. Crews and colleagues, writing in Diabetes Care in 2016, demonstrated that adherence — not device type alone — was a key determinant of healing in patients prescribed removable cast walkers. Subsequent research summarized in the IWGDF 2023 documents indicates that fewer than half of patients wear their prescribed therapeutic footwear for more than 60% of daytime hours, and that overall adherence with footwear recommendations falls in the 28–60% range.
A 2022 scoping review by Jarl and colleagues identified consistent barriers: device weight and bulk, perceived appearance, postural instability, daily activity limitations, and the incompatibility of bulky walkers with normal clothing and routines. These factors help explain why a non-removable device — which removes the daily decision to comply — is associated with both higher healing rates and lower non-adherence.
Beyond Healing: Pressure-Guided Footwear and Recurrence Prevention
Healing a DFU is only the first step. Approximately 40% of patients re-ulcerate within one year of wound closure, and the foot in remission therefore requires ongoing offloading. Two practical targets have emerged from the literature aggregated in the IWGDF 2023 guidance: maintaining in-shoe mean peak plantar pressure below approximately 200 kPa, and achieving therapeutic footwear adherence above 80% of weight-bearing time. Patients whose therapeutic footwear has been modified using individualized plantar pressure measurements have shown substantial relative reductions in plantar ulcer recurrence compared with standard therapeutic footwear.
Emerging technologies are being studied to support both pressure reduction and adherence. A 2019 proof-of-concept randomized study by Abbott and colleagues in The Lancet Digital Health reported reduced plantar ulcer recurrence using an intelligent insole system that delivered real-time pressure alerts. A 2024 review by Bus and colleagues describes how design changes, telehealth monitoring, and pressure-sensing technologies are being explored to address adherence barriers without sacrificing biomechanical effectiveness, although larger confirmatory trials are still needed.
Clinical Summary
For an active neuropathic plantar ulcer, a non-removable knee-high device — most often a total contact cast — produces the highest healing rates and the shortest healing times. When a non-removable option is not feasible, removable knee-high devices are the next best choice, with properly fitted footwear and felted foam reserved as a fallback. After healing, pressure-guided custom orthoses combined with sustained daily adherence are central to reducing the substantial baseline risk of recurrence. Across every phase, adherence behaviour is as important as device selection.
References
- Bus SA, Armstrong DG, Crews RT, et al. Guidelines on offloading foot ulcers in persons with diabetes (IWGDF 2023 update). Diabetes/Metabolism Research and Reviews. 2024;40(3):e3647.
- Schaper NC, van Netten JJ, Apelqvist J, et al. Practical guidelines on the prevention and management of diabetes-related foot disease (IWGDF 2023 update). Diabetes/Metabolism Research and Reviews. 2024;40(3):e3657.
- Chen L, Sun S, Gao Y, et al. Total contact casts versus removable offloading interventions for the treatment of diabetic foot ulcers: a systematic review and meta-analysis. Frontiers in Endocrinology. 2023;14:1234761.
- Lazzarini PA, Jarl G, Gooday C, et al. Effectiveness of offloading interventions for people with diabetes-related foot ulcers: a systematic review and meta-analysis. Diabetes/Metabolism Research and Reviews. 2024;40(3):e3650.
- Crews RT, Shen BJ, Campbell L, et al. Role and determinants of adherence to off-loading in diabetic foot ulcer healing: a prospective investigation. Diabetes Care. 2016;39(8):1371–1377.
- Jarl G, van Netten JJ, Lazzarini PA, et al. Offloading treatment in people with diabetic foot disease: a systematic scoping review on adherence to foot offloading. Diabetes & Metabolic Syndrome: Clinical Research & Reviews. 2022.
- Bus SA, Lazzarini PA, Schaper NC. Offloading and adherence through technological advancements: modern approaches for better foot care in diabetes. Diabetes/Metabolism Research and Reviews. 2024.
- Abbott CA, Chatwin KE, Foden P, et al. Innovative intelligent insole system reduces diabetic foot ulcer recurrence at plantar sites: a prospective, randomised, proof-of-concept study. The Lancet Digital Health. 2019;1(6):e308–e318.
Comments
