Put Your Best (Diabetic) Foot Forward

Patients diagnosed with diabetes mellitus have an estimated 15% likelihood of developing a diabetic foot ulcer (DFU), which also puts them at substantial risk for amputation.¹ Known comorbidities relevant to foot ulcers in patients with diabetes involve a combination of diabetic neuropathy, peripheral vascular disease, deformity, and trauma—all associated with the chronic complications of diabetes. Not until the patient has been assessed and helped to manage these factors can wound care for a DFU be provided with any expectation of success.

Overall Health

Wounds become chronic only when underlying factors impede healing. This once again underscores the need to obtain a complete patient history. The patient’s general health symptoms typically are reviewed from the head down, keeping in mind the major complications from diabetes—eg, stroke, retinopathy, heart and kidney problems, hypertension, peripheral vascular disease, and neuropathy—can occur. A blood test for hemoglobin A1C levels (ideal control under 0.084 or 8.4%) can provide accurate assessment of diabetes control and offers reliable insight into how well the diabetes is being managed.² 

Comorbid conditions and medicines also are important in determining how well the patient with a DFU will heal. Physicians should be aware of emotional health risks, such as lowered self-esteem³ and depression⁴, which are associated with DFUs and can interfere with healing.

Once the patient’s health status is acknowledged and confounding factors are as controlled as possible, wound healing can be addressed. 

Assessing Risk

Boulton et al⁵ concluded that although the most serious and costly complications of diabetes, foot ulcers are mostly preventable, partly through screening feet at risk. The question may be how often to screen/assess. In a prospective, descriptive study to assess use of a rapid foot screen, Carreau et al⁶ found that Inlow, the 60-second diabetic foot screen tool, took an average of 7 minutes to complete and recommended its administration (with some reservations; data were inconclusive) every 3 months in patients at risk for DFU.

Treatment and Care 

The patient should be provided with evidence-based, standard, topical approaches, including debridement of noneschar tissue and appropriate dressings that manage infection and moisture. Standard care also may include offloading. More advanced topical wound care might include: platelet-rich plasma gel, which was supported by a retrospective, longitudinal study of 39 patients where most patients healed after the plasma gel was implemented,⁷ and topical hyperbaric oxygen therapy (HBOT), which was confirmed in a prospective, controlled study of 28 patients who healed better after topical HBOT versus the control group that used a silver dressing.⁸ 

Other treatment options include:

• Total contact casting (TCC). This offloading approach relieves pressure, offers a moist environment for healing, and allows the patient to ambulate versus remain immobile. Unfortunately, due to the limited number of competent, knowledgeable, board-certified pedorthists (BCPs) with experience in applying and modifying the casts, as well as the time involved for the procedure (usually 45 minutes, plus time for cast removal and assessment), TCC is not widely used. 

However, it is worth considering. 

A recent case study⁹ exemplifies the success of treating DFUs with TCC. The care team includes a BCP experienced in TCC. Their patients are evaluated for peripheral circulation and perfusion to the lower extremities; lower extremity weakness, motor imbalances, and unsteady ambulation that might make TCC unsafe; and sufficient cognitive ability to follow instructions regarding the use of assistive devices (eg, canes or walkers). If findings are sufficient, patients with ulcers on weight-bearing surfaces, such as DFUs, are considered for TCC. 

In 1 case, a woman with an ulcer >18 months duration was provided TCC and a variety of topical wound dressings when wound healing seemed to slow. The casting stabilized the local wound environment, keeping the patient infection-free for 5 years until the wound closed. Moisture-control foam dressing impregnated with nanocrystalline addressed moisture balance and bacterial control necessary to achieve healing within the closed, protected environment created by TCC until the wound finally responded. TCC appeared to provide a healing environment for this serious wound. 

• Nonweight-bearing exercise. Preliminary research suggests exercise therapy may increase joint mobility and blood flow to enhance wound healing potential. A 12-week, prospective, quasi-experimental pilot study¹⁰ assessed the effect of nonweight-bearing ankle exercises on the size of neuropathic, diabetic foot wounds in community-dwelling older adults; 10 were randomized to ankle exercise treatments and 9 continued their previous care regimen. Wound reduction between groups was not significantly different, but the results of this pilot study show exercise didn’t impede healing. 

• Nonlocalized hyperbaric oxygen therapy (HBOT). Although adverse effects of local HBOT have not been well-studied, the results of a prospective, randomized controlled study¹¹ on the effects of HBOT on ulcer tissue, which found ulcer size decreased significantly after 2 weeks of HBOT treatment compared to the control group; researchers noted that oxidative stress in local ulcer tissue could accumulate and might offset long-term healing. Thus, the prolonged, inappropriate, and/or unnecessary HBOT treatments should be avoided. 

• Umbilical cord-based technology. Human dermal substitutes have shown positive effects on healing. A cryopreserved umbilical cord allograft for the treatment of chronic DFU (Neox Cord 1K, Amniox Medical) is currently in clinical trial; the product is comprised of amniotic membrane and umbilical cord tissues that contain key proteins, cytokines, and growth factors shown to curb inflammation and spur regeneration of normal tissue. The natural biological and structural integrity of these tissues is preserved using cryopreservation technology. Placental tissue technology already has proven to decrease scar tissue and reduce inflammation in ophthalmic procedures. 

A trial of 30 patients with nonhealing DFUs in the multicenter, randomized, CONDUCT 1 study is being planned to determine whether such technology is clinically effective and cost-efficient, and whether it can reduce the number of amputation in people with diabetes.

Wounds, particularly of the feet, can be difficult to heal in patients with diabetes. Although research offers numerous practice options, the evidence base leaves room for questions as well as promise. When standard topical care does not seem to be working, clinicians should ensure the patient is in the best condition to heal and investigate adjunctive options and specialists to expedite the care/healing process.

References:

1. Allen HB, Vaze ND, Choi C, et al. The presence and impact of biofilm-producing staphylococci in atopic dermatitis. JAMA Dermatol. 2014;150(3):260-265.

2.Ciacci C, Cavallaro R, Iovino P, et al. Allergy prevalence in adult celiac disease. J Allergy Clin Immunol. 2004;113(6):1199-1203.

3.Costerton JW, Stewart PS, Greenberg EP. Bacterial biofilms: a common cause of persistent infections. Science. 1999;
284(5418):1318-1322.

For more on wound care and pain, visit the Dermatologic Disorders and Pain Medical Resource Centers on our website at www.consultant360.com.