CLINICAL

Overview

For guidelines and quality measures related to DFUs, see topic "Diabetic Foot Ulcer - Overview". For an introduction and assessment of DFUs including epidemiology, risk factors, etiology, pathophysiology, history, physical examination, diagnosis, differential diagnoses, documentation and ICD-10 coding, see "Diabetic Foot Ulcers - Introduction and Assessment". For management of DFUs, see topics "Diabetic Foot Ulcer - Treatment",  "Diabetic Foot Ulcer Associated with infection - Management","Diabetic Foot Ulcer Associated with Ischemia - Revascularization".

Frequency of foot evaluation

• 1CAll adults with diabetes should undergo a comprehensive foot evaluation at least annually by physicians (MD, DO, DPM) or advanced practice providers with training in foot care (Grade 1C).[6][7][4][5][3]
• Rationale:  Identification of the high-risk foot is an essential component of diabetes care. It focuses attention and provides a means to direct limited resources to those patients most at risk of developing a DFU.[8] Detailed foot assessments may occur more frequently in patients with histories of ulcers or amputations, foot deformities, insensate feet, and peripheral arterial disease (PAD). Simplified foot inspections should occur at every visit in all patients with diabetes.[5]

Foot evaluation

• Clinical examination is useful in the classification and risk stratification of the disease for appropriate monitoring in a diabetic foot clinic.[5]
• A comprehensive foot examination, recommended at least annually for all patients with diabetes, is described in the section 'Assessment' in "Diabetic Foot Ulcer - Introduction and Assessment".
• A more simplified short evaluation can be used at every visit in all patients with diabetes [5]:
• Simplified 60 Second Diabetic Foot Screening Tool [9]
• Inlow's 60-second Diabetic Foot Screen [10][11]
• 3-Minute diabetic foot evaluation [12]
• See Quick Reference Guides 'Clinician Guide for the Diabetic Foot Exam' and the '60-Second Screen For The Diabetic Foot' below:

Quick Reference Guide 1: Clinician Guide for the Diabetic Foot Exam 

Quick Reference Guide 2: 60-Second Screen For The Diabetic Foot

Risk stratification tool

• Clinicians can choose among many risk classification tools. [6][7][8][11] Table 1 shows a risk stratification system developed by the International Working Group on Diabetic Foot (IWGDF) [3][13], along with ulcer and amputation estimated incidence per category, recommended follow up and preventative recommendations. 

Table 1. The IWGDF Risk Classification System (2015), preventative screening frequency and interventions [6][3][8]

Preventative Interventions

The American Health Organization (PAHO) reported 3 key cost-saving health service interventions needed to fight diabetes in the Americas [8][14]: glycemic control in people with hemoglobin A1c >9%, blood pressure control in people with pressure >160/95 mmHG, and foot care in people with a high risk of ulcers. In the Western world, tight control with a target for hemoglobin A1c<7% and blood pressure < 130 /85 mmHg are suggested.[8] Foot care includes educating diabetic patients on recognizing and treating minor foot injuries, the use of appropriate footwear, and accessing knowledgeable health care personnel.[14]

General

For all patients with diabetes (IWGDF Categories 0-3)

• 2BFor all patients with diabetes, the Society for Vascular Surgery suggests adequate glycemic control (i.e., target hemoglobin A1c<7% with strategies to minimize hypoglycemia) to reduce the incidence of diabetic foot ulcers (DFUs) and infections, with subsequent risk of amputation (Grade 2B).[4]
• 1CFor all patients with diabetes with pre-ulcerative signs (e.g. callus, blisters, ingrown or thickened toe nails, fungal infections), the IWGDF recommends clinicians either treat the pre-ulcerative sign or refer to a foot care professional who can treat them (Grade 1C) [3]
• • Rationale: Pre-ulcerative signs on the foot, such as callus, blisters or hemorrhage, appear to be a strong predictor of future ulceration and require immediate treatment by a foot care professional. The benefits of treatment of pre-ulcerative signs by a trained foot care professional outweigh the potential harm of such treatment and come at relatively low costs. [3]

• Consultation and follow up with specialists below are recommended [6]:
• Patients with peripheral neuropathy with foot deformity need a referral to a foot care specialist 
• Patients with PAD need referral to a vascular specialist 

Self-management interventions

For at-risk patients (IWGDF Categories 1-3)

• 2CFor at-risk patients, self-care behaviors should be included as part of an integrated foot care that includes professional foot care, education and therapeutic shoes and insoles.(Grade 2C).
• Rationale: Self-care behaviors include good foot care, daily foot and shoes inspection, daily foot washing (with careful drying particularly between the toes), avoidance of chemical agents or plasters to remove callus or corns, use of emollients to lubricate dry skin and cutting toenails straight across.[1][3] Good foot care and daily inspection alone without the other interventions will not reduce the recurrence of DFU.[1]
• 2BFor higher-risk patients (IWGDF Categories 2 and 3), the IWGDF recommends clinicians instruct patients to monitor foot skin temperatures at home to prevent a first or recurrent plantar foot ulcer. (Grade 2B)
• • Rationale: The goal of temperature monitoring is to identify early signs of inflammation, so that timely action can be taken by patient and care provider to resolve the cause of inflammation.[3] There is moderate-certainty evidence (evidence level B) supporting use of infrared thermometer to prevent first or recurrent ulcer, by having the patient monitor plantar foot skin temperature on a daily basis, with subsequent preventative actions if elevated temperatures are noted.[3] However, cost-effectiveness is still unknown, and there are potential hurdles to adoption (e.g., calibrated equipment may be difficult to find, and patients - particularly those without an active ulcer - might see daily monitoring as a burden). [3]

Integrated Foot care

FOR AT-RISK PATIENTS WITH HISTORY OF ULCER OR AMPUTATION (IWGDF CATEGORY 3)

• 1CTo prevent a recurrent foot ulcer in an at-risk patient with diabetes, the IWGDF recommends clinicians provide integrated foot care, which includes professional foot treatment, adequate footwear and education (Grade 1C). [3] This intervention should be repeated or re-evaluated once every 1 to 3 months as necessary. [3]

Footwear and offloading devices to prevent DFU recurrence

For all patients with diabetes (IWGDF Categories 0-3)

• 1CFor all patients with diabetes, the IWGDF recommends clinicians instruct patients not to walk barefoot, in socks only, or in thin-soled standard slippers, whether at home or when outside (Grade 1C). [15]

For at-risk patients (IWGDF Categories 1-3)

• For at-risk patients (IWGDF Categories 1-3), the IWGDF recommends properly fitting footwear to prevent a first foot ulcer (Grade 1C). Patients with peripheral neuropathy only (IWGDF Category 1) and no calluses may wear properly fitting over-the-counter shoes and insoles; others should wear therapeutic shoes.[15]
• • Rationale: There is some evidence that properly fitting footwear is effective in helping prevent DFU. Little harm has been reported from properly fitting therapeutic footwear, thus benefit likely outweighs potential harm.
  • Medicare will not cover therapeutic footwear for patients with diabetes and peripheral neuropathy without evidence of calluses. Therefore if patient does not have calluses, patient may opt to wear properly fitting over-the-counter shoes and insoles instead. Patients who have not yet suffered from a DFU may be more inclined to wear regular over-the-counter shoes, as those are less bulky. [15]
• 1C For patients with diabetes at-risk of developing DFUs (IWGDF Categories 1-3), we recommend use of therapeutic shoes, custom-made insoles or toe-orthosis to prevent a first foot ulcer, either plantar or non-plantar, or a recurrent non-plantar foot ulcer. If foot deformity or pre-ulcerative lesion is present, therapeutic shoes are recommended (Grade 1C) [1][4][15]  
• 1BTo prevent a recurrent plantar foot ulcer in an at-risk patient with diabetes (IWGDF Categories 1-3), the IWGDF recommends therapeutic footwear that can relieve plantar pressure during walking (i.e., 30% relief compared with plantar pressure using standard care therapeutic footwear) (Grade 1B) [15]
• • Rationale: Few adverse effects have been reported, such that benefits outweigh potential harms. Patients need to be encouraged to constantly wear their therapeutic footwear, even at home. Unfortunately, patient adherence to prescription footwear is often insufficient and requires further attention to reduce the risk for re-ulceration.[15] If for religious, cultural reasons patients prefer not to wear same street shoes at home, a pair can be prescribed for indoor use (although a second pair in the same year will not be covered by Medicare). To ensure effective offloading, when resources allow, footwear should be designed or evaluated using plantar pressure measurement. Use of pressure measurement devices to ensure adequate offloading is likely cost-effective as it has been shown to reduce risk of ulcer recurrence by 50%.[15] If plantar foot pressure cannot be measured, clinicians should prescribe therapeutic footwear that effectively offload the foot. Medicare covers therapeutic shoes for patients with diabetes at higher risk of DFU. [16][17]

Preventative Surgical Procedures

For patients with PAD at higher risk of DFU (IWGDF Category 2 and 3)

• 1CFor patients at higher risk of developing DFU, but with no peripheral artery disease, the Society for Vascular Surgery recommends against prophylactic arterial revascularization to prevent DFU (Grade 1C, against).[4]
• • Rationale: Assessment of ischemia as a factor contributing to development or non-healing of ulceration is essential. However, the neuropathy seen in diabetes is not primarily ischemic in nature, and there is no evidence that revascularization reverses ischemic neuropathy except in the setting of acute ischemia.[4] Thus, primary foot ulcerations in diabetic neuropathy are unlikely to be directly related to impaired large-artery blood flow; rather, they are related to abnormal gait and foot weight distribution. Indications for arterial revascularization should be based on the standard indications of severe claudication, rest pain, and tissue loss.[4]

• For patients at higher risk of developing DFU and foot deformity, consider prophylactic surgery to correct deformity if deformity is not properly accommodated by therapeutic shoes/insoles.[6]
  

For patients at risk of DFU recurrence (IWGDF Category 3)

• 2C For patients at high-risk of recurrence of DFU, with a plantar forefoot DFU that recurred despite adequate preventative interventions (e.g., therapeutic footwear), the IWGDF suggests surgical offloading to prevent recurrence (e.g. Achilles tendon lengthening, joint arthroplasty, single or pan metatarsal head resection) (Grade 2C) [15]

• • Rationale: Interestingly, surgical offloading seems more effective in preventing than in healing ulcers.[15][18] However, due to the possible complications and side effects of these surgical offloading techniques (e.g. infection, gait problems, acute Charcot neuro-osteoarthropathy (CN), transfer ulcers) and also due to higher costs compared to non-surgical prevention, surgical offloading procedures should be considered only if standard offloading fails.
• For patients at high-risk of recurrence of DFU, with a toe DFU that recurred despite adequate conservative offloading, the IWGDF suggests digital flexor tenotomy to prevent recurrence (Grade 2C)
• • Rationale: Evidence drawn from observational studies (evidence level C) support digital flexor tenotomy to prevent recurrence of toe DFUs, if standard offloading fails. This procedure can be performed in an outpatient setting and is not likely to have a negative impact on foot function.[15]

PATIENT EDUCATION (for clinicians)

Preventing first-time and recurrent DFUs

• 1C For all patients with diabetes (IWGDF Categories 0-3), we recommend repeated educational sessions aimed at improving foot care knowledge and adherence to foot care advice to prevent first or recurrent DFU (Grade 1C)
• • Rationale: There is some evidence that short (1-hour) educational sessions on foot care do not decrease DFU incidence among patients with diabetes compared to patients who do not receive any education (Evidence level C).[19][20] However, there is also evidence that patients who are adherent to the advice given in the education program are at much lower risk of developing a first ulcer than those who are not adherent (evidence level C). [19] In order to be adherent to any advice though, patients need to be told and understand their role in foot care. As a result, clinical guidelines recommend clinicians provide education regularly.[4][3][15] Reinforcing foot care education to patients and their caregivers at every follow up visit is likely cost-effective[4], and considered a need for adequate foot care by the PAHO. [14]
• Patient education topics and frequency can be tailored according to which IWGDF risk category the patient falls under. See section 'Risk stratification tool' above. See Table 2 for suggested programs

Table 2: Suggested patient education program according to IWGDF Risk Categories [3][4]