Offloading is a large piece of the puzzle for treating diabetic foot ulcers, with non-removable devices providing the best pressure relief. These authors discuss effective offloading devices, addressing challenges with patient adherence to offloading regimens.
Offloading the diabetic foot has become an area of confusion and one that unfortunately has developed a group of “pharisees” on the subject, depending on the side you are on. We wish health care were that cut and dry, but it’s not.
Using a reliable guideline is the best way to be sure you are applying best practice to your patients, and in our opinion, there is no more reliable guideline than the International Working Group on the Diabetic Foot’s (IWGDF) periodic review of research in the field of diabetic foot management. The group is practical and recognizes the need to modify your approach based on the needs and restrictions your particular patient presents with.
After many years, the total contact cast (TCC), once praised as the “gold standard” for treatment of neuropathic plantar ulceration, has been equaled and in many cases replaced by the knee high non-removable walker recommended by the IWGDF.1-6 The success of these devices can be attributed to their ability to unload the plantar foot and maintain protection of the foot through the use of a non-removable system.
When properly applied these devices are able to significantly reduce the plantar pressure and shear forces associated with the formation of neuropathic ulcers, thereby maximizing wound healing potential. Because these devices are not always available for a number of reasons, numerous other devices, techniques, and modifications have been utilized to achieve the goals of wound healing and patient mobility.7-12 These have included modifications to the foot bed of a removable device, pixelated offloading insoles, specifically designed healing shoes, and even modifications to the standard depth footwear used for everyday activities.
What has been made abundantly clear by research over the past several years is that any offloading device works better than the patient’s own shoe, and non-removable devices work best of all.13
Despite their proven track record, non-removable knee-high devices are under-utilized in daily practice.14,15 Fife et al found that of all the sites surveyed, only 6% of patients received treatment with a TCC.15 In a similar study of 895 clinics that treat diabetic foot ulcerations, Wu et al concluded that only 1.7% of centers routinely use TCCs, and up to 41.2% of respondents utilize much less successful and often ineffective shoe-based modification techniques instead.14
Reasons for this lack of support for non-removable offloading devices were attributed to patient tolerance (55.3%), the time needed to apply the device (54.3%), cost of materials (31.6%), reimbursement issues (27.5%), familiarity with method of application (25%), customizing parts (20.9%), staffing/ordering supplies (15.2%), and clinician coverage (10.6%).14 Also of significance is a high perceived complication rate during treatment with a TCC.16 Many clinicians expressed concern over the need for frequent TCC changes and close monitoring of the patient. This seems odd because the single most effective thing we utilize is weekly visits, appointments on demand for complications, and regular reinforcement of the need for aggressive offloading.
A Closer Look at the Challenges of Offloading
Offloading devices need to address several different challenges present in the diabetic foot. High direct pressures are associated with excess weight, stiffness of foot structures, and sagittal plane osseous deformities. Anterior posterior shear is recorded during ambulation at heel strike and push off, and transverse shear noted with lateral weight shift. Twisting of the foot on the ground produces a rotary shear that occurs with an abducted gait, pronatory collapse, and direction change. Footwear choices directly affect load distribution with many shoes increasing pressures at points of contact. A patient’s choice of activity, whether job related or not, provides the practitioner with challenges associated with temporal management, actual time on the foot, speed of gait, and distribution of forces across the gait cycle.
Patients present with psychological challenges that affect adherence to offloading schedules and the use of prescribed devices complicated by a lack of sensation or a warning system to indicate discomfort with overstress.
Patient adherence is no small issue and is affected by a number of variables, not all of which are easily managed. Many patients come with a poor understanding of the disease process despite efforts to educate them. Their footcare knowledge is often minimal and what they have grasped is only partially adopted. This leads to a spotty adherence history that is often accompanied by practitioner burnout after years of frustration in dealing with the effects of blatant resistance to the treatment regimens prescribed. Armstrong et al reported that patients treated with a removable device wore the device a total of 28% of their daily activity with even the most compliant population not exceeding 60%.17
Granted, some of our dressing, offloading, and medication requests are complex and often practitioners do not have the time, patience, or teaching skills needed to reinforce the particulars of therapy. Patients have to buy into the program and actually believe in your sincerity and trust your ability to get them well. They can’t feel subtle changes in blood sugar, see rapid improvements in a wound in one or two weeks, or improve their fitness with a short-term investment in exercise. They don’t have the advantage of years of medical study and regular conference reinforcement to boost their confidence in your ability to heal them. And you don’t have the time to drive it home to them or their family in one 30-minute visit once a week.
Dr. McGuire takes the advice of a psychiatrist friend who said the only way to get through to a patient with diabetes is “constant unrelenting reinforcement through regular visits and repetition of goals.” He altered this and applied it to his practice utilizing “weekly visits until wound closure, regardless of progress with 24/7 access to advice or examination for complications.”
Without this level of patient cooperation and physician empathy the offloading device is secondary to healing. The TCC is the quintessential offloading device due to its level of “forced adherence” and magnificent track record but its not perfect. In addition to several contraindications to its use, which have been well outlined in the literature, patients periodically disappear with the devices for weeks on end, cut the devices off themselves, get them wet, stick things down in them, or participate in things like cruises or exotic vacations with them on.
Yes, all these have happened to us, some with disastrous results like limb amputation. Has this deterred us from using non-removable devices? Heck no. The complication rate is very low and for the most part they are minor. This has been proven years ago by numerous evaluations of the TCC and should help to boost your confidence.16-22
Still, TCC usage numbers remain low. This has led researchers and inventors to come up with alternatives to the available non-removable devices. TCC kits have made it easier and less expensive to apply the devices, fracture boot or controlled ankle motion walkers are readily available and can be made non-removable with several readily available items, the best of which is a simple cable tie. Companies have devised elaborate boot-shoe systems to utilize the Transitional Offloading concept Dr. McGuire developed in 2006.10,11,23,24
Unusual bracing devices have been made such as the T-Brace™ or the TOAD Medical Anti-Gravity Brace™ (Toad Medical) to attempt to completely offload the foot.25 And ambulatory aids have been devised to improve mobility during offloading such as the Knee-Roller™, the iWALK2.0™ (iWALKFree), and the Freedom Leg™ (Forward Mobility). These always seem to have been developed by 20- to 40-year-old medical engineers or entrepreneurial practitioners who never bothered to test it on the typical 70-year-old neuropathic diabetic patient with arthritis, obesity, and severe balance challenges. Oh yes—and with poor insurance and limited resources to invest in, these difficult-to-use offloading devices will end up in a closet.
In the end we have to apply best practice that in our judgment will bring about the best outcome we can expect with this patient. So, the big pearl is be patient with your patient and yourself. Treat them as you would like to be treated and most, not all, will get better and heal.
Dr. McGuire is a Clinical Professor at the Temple University School of Podiatric Medicine. He also serves as director of the Foot and Ankle Institute's Leonard Abrams Center for Advanced Wound Healing. He is a founding member of the Academy of Physicians in Wound Healing, the American Professional Wound Care Association, and the Council for Medical Education and Testing. He is very involved in research with several active research trials and numerous papers in the area of wound healing, offloading, diabetic foot care and biomechanics of the foot and ankle.
Dr. Aung is Chief of the Podiatry Section of the Tenet Health System/St. Joseph’s Hospital and a panel physician at Tenet Health System/St. Mary’s Hospital Outpatient Wound and Hyperbaric Center in Tucson, Ariz. She is a member of the American Podiatric Medical Association (APMA) Coding Committee, the APMA MACRA/MIPS Task Force and is on the Exam Committee of the American Board of Wound Management. Dr. Aung is also on the Editorial Review Board for Wound Management and Prevention and a Fellow of the Academy of Physicians in Wound Healing. Her website is www.healthy-feet.com.
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