Diabetic foot ulcers (DFU) pose significant challenges in clinical management, often requiring effective offloading strategies to promote healing and prevent complications. Offloading devices aim to alleviate high plantar tissue stress by diminishing plantar pressure, minimizing weight-bearing activity, and increasing treatment compliance.^1-4 With the 2023 International Working Group on the Diabetic Foot (IWGDF) guidelines serving as our compass, let's delve into various essential offloading options clinicians should know.

Nonremovable Knee-High Options

Nonremovable knee-high offloading devices, such as total contact casting (TCC) and instant total contact casting (iTCC), are integral in managing DFUs. The 2023 IWGDF Guidelines regards these nonremovable devices as the gold standard for offloading DFUs.^5,6 Specifically, the literature supports using nonremovable knee-high devices to offload DFUs in the plantar forefoot or midfoot region with mild infection or mild ischemia.^5,6

Application of a total contact cast involves meticulously molding it to the foot and ankle, delivering contact and support while allowing for limited movement.^1,2 iTCC devices are typically prefabricated, knee-high cast walkers that clinicians can transform into non-removable devices by applying an adhesive wrap.^3,5-8 These devices provide consistent pressure distribution, immobilization, and protection, beneficial in instances of severe peripheral and motor neuropathy.^2,3,5,9,10 

Piaggesi et al compared a prefabricated irremovable device with traditional TCC for managing DFUs in outpatients with neuropathic plantar ulcers.¹⁰ This study found similar effectiveness between the prefabricated device and traditional TCC in terms of healing rates and adverse events. Additionally, the prefabricated offloading device reduced treatment costs in their study by 78% compared to TCC.¹⁰ Moreover, the walker demonstrated better practicability, with a 77% reduction in application time and a 58% reduction in removal time compared with TCC, resulting in higher patient satisfaction.¹⁰ Additionally, a meta-analysis from 2023 encompassing 4 RCTs suggested comparable healing outcomes between TCC and nonremovable walkers, further supporting the efficacy of both approaches.⁸ Although these devices are the gold standard in offloading DFUs, patients may face challenges with compliance due to factors such as job commitments, driving, limited access to wound care clinics, and obstacles from hot climates.^3,5,7,8

Removable Offloading Devices

Clinicians may consider utilizing removable knee-high or ankle-high devices as alternatives to nonremovable ones, especially when consistent wound monitoring and mobility is necessary. These offloading devices include removable knee-high walkers, customized bivalved TCCs, lower height cast walkers, forefoot offloading shoes, rearfoot offloading shoes, cast slippers/shoes, and postoperative healing shoes.^3,5-7 These are considered second-tier offloading devices.^3,5-7

As per the 2023 IWGDF guidelines, if both mild infection and mild ischemia are present or if either moderate infection or moderate ischemia is present, a provider should consider using a removable knee-high or ankle-high offloading device.⁶ If both moderate infection and moderate ischemia are present, or if either severe infection or severe ischemia is present, the IWGDF guidelines recommend addressing the infection or ischemia primarily and then using a removable device.^6,8 According to a recent meta-analysis, there appears to be minimal to no difference in the rates of wound healing between removable knee-high and removable lower height offloading devices.⁸ Based on the findings of this study, the IWGDF committee updated the 2023 guidelines to classify both options under second-line therapy.

Medical-Grade Footwear

Medical-grade footwear plays a critical role in DFU wound management and is classified as third-line therapy.⁶ Medical-grade footwear is a viable option for individuals with DFUs when nonremovable or removable devices are unavailable or contraindicated.⁶ Crafted with high-quality materials, this footwear design aims to address the unique needs of patients with or at high risk for foot ulcers. The construction of these shoes usually has extra depth and a wide toe box with soft inner linings to accommodate foot deformities and bony prominences.^5,6 They may have custom insoles, adjunctive features like foam or felt padding, and/or rocker bottom soles.⁶ It is important to note that these shoes are best used in conjunction with (not as a replacement for) proper offloading techniques, and are not recommended as standalone treatments for DFU.⁶

Surgical Offloading

Surgical offloading is a consideration when conservative options are insufficient, providing targeted relief for nonhealing ulcers resistant to standard treatment alone. A nonhealing ulceration is typically defined as a DFU that fails to decrease in size by >50% within 4-6 weeks of treatment.^1,3,5-7 Some clinicians may also consider surgical offloading when appropriate for patients at high risk for DFU, or to mitigate the risk of ulcer recurrence after initial DFU healing.

For ulcerations on the lesser toes with flexible deformities, the IWGDF guidelines recommend consideration of a digital flexor tenotomy in conjunction with an offloading device.⁶ Additionally, if a plantar metatarsal head ulceration does not heal with traditional offloading alone, options such as Achilles tendon lengthening, metatarsal head resection, or metatarsal osteotomy may be considered, depending on the severity of the deformity, in conjunction with an offloading device.^5,6 Moreover, if a plantar hallux wound does not respond to offloading alone, clinicians could explore joint arthroplasty combined with an offloading device.⁶ For non-plantar ulcerations, various interventions, including removable offloading devices, footwear adjustments, toe spacers, custom orthoses to address biomechanical deformities, or digital flexor tenotomies in the presence of a dorsal toe wound can be beneficial.^5,6 Accordng to a 2021 review by Lazzarini and Jarl, “Contraindications to these surgical procedures include moderate-to-severe ischemia, moderate-to-severe infection, and moderate-to-severe edema.”⁵

In Conclusion

One must not neglect the non-involved side when looking at offloading for DFU. The 2023 IWGDF guidelines recommend considering implementing a shoe lift on the contralateral side when utilizing an offloading device.^5,6,8 This aims to enhance balance, comfort, and compliance of the offloading device while accommodating what effectively becomes a functional limb-length discrepancy.^5,6

Effective offloading is paramount when managing diabetic foot ulcers, and clinicians must be well-versed in offloading options tailored to individual patient needs. By implementing the offloading pathway outlined in 2023 IWGDF guidelines and drawing insights from various meta-analysis studies, healthcare professionals can navigate the complexities of DFU management with confidence, ultimately improving patient outcomes and quality of life.

Dr. Gandhi Patel is a diplomate of the American Board of Podiatric Medicine and has practiced in North Carolina and New Jersey.

References

1. Jeffcoate WJ, Bus SA, Game FL, et al. Reporting standards of studies and papers on the prevention and management of foot ulcers in diabetes: required details and markers of good quality. Lancet Diabetes Endocrinol. 2016;4(9):781-788. doi:10.1016/S2213-8587(16)30012-2

2. Lazzarini PA, Jarl G, Gooday C, et al. Effectiveness of offloading interventions to heal foot ulcers in persons with diabetes: a systematic review. Diabetes Metab Res Rev. 2020;36 Suppl 1(Suppl 1):e3275. doi:10.1002/dmrr.3275

3. Bus SA, Armstrong DG, Gooday C, et al. Guidelines on offloading foot ulcers in persons with diabetes (IWGDF 2019 update). Diabetes Metab Res Rev. 2020;36 Suppl 1:e3274. doi:10.1002/dmrr.3274

4. Lazzarini PA, Crews RT, van Netten JJ, et al. Measuring Plantar Tissue Stress in People With Diabetic Peripheral Neuropathy: A Critical Concept in Diabetic Foot Management. J Diabetes Sci Technol. 2019;13(5):869-880. doi:10.1177/1932296819849092

5. Lazzarini PA, Jarl G. Knee-High Devices Are Gold in Closing the Foot Ulcer Gap: A Review of Offloading Treatments to Heal Diabetic Foot Ulcers. Medicina (Kaunas). 2021;57(9):941. Published 2021 Sep 6. doi:10.3390/medicina57090941

6. Bus SA, Armstrong DG, Crews RT, et al. Guidelines on offloading foot ulcers in persons with diabetes (IWGDF 2023 update). Diabetes Metab Res Rev. 2024;40(3):e3647. doi:10.1002/dmrr.3647

7. Fernando ME, Horsley M, Jones S, et al. Australian guideline on offloading treatment for foot ulcers: part of the 2021 Australian evidence-based guidelines for diabetes-related foot disease. J Foot Ankle Res. 2022;15(1):31. Published 2022 May 5. doi:10.1186/s13047-022-00538-3

8. Lazzarini PA, Armstrong DG, Crews RT, et al. Effectiveness of offloading interventions for people with diabetes-related foot ulcers: A systematic review and meta-analysis. Diabetes Metab Res Rev. 2024;40(3):e3650. doi:10.1002/dmrr.3650

9. Armstrong DG, Boulton AJM, Bus SA. Diabetic Foot Ulcers and Their Recurrence. N Engl J Med. 2017;376(24):2367-2375. doi:10.1056/NEJMra1615439

10. Piaggesi A, Macchiarini S, Rizzo L, et al. An off-the-shelf instant contact casting device for the management of diabetic foot ulcers: a randomized prospective trial versus traditional fiberglass cast. Diabetes Care. 2007;30(3):586-590. doi:10.2337/dc06-1750