Classification Systems in Diabetic Foot Ulcers

As the prevalence of diabetes in the United States today is growing, so is the number of complications related to diabetes including diabetic foot ulcers. Roughly 15-20% of the 16 million Americans with diabetes will be hospitalized with complications related to foot ulcers.  Approximately 85% of diabetes-related lower extremity amputations are preceded by foot ulcers, and the post-amputation mortality rate for these patients can very high.  To best treat these patients, nurses must educate themselves on how to recognize, assess, classify, and care for patients with diabetic foot ulcers. Early recognition and classification of diabetic foot ulcers can help prevent toe, foot, or lower extremity amputation.  This can be confusing for many nurses because there are multiple classification systems out there for DFUs or diabetic foot ulcers. These systems include the Wagner Diabetic Foot Ulcer Classification System, the University of Texas Diabetic Foot Ulcer Classification System, and the Diabetic Ulcer Severity Score (DUSS) just to name a few. It is important that nurses recognize that they are the gateway to limb and life salvation for many diabetic patients.

The Wagner Diabetic Foot Ulcer Classification

The Wagner Diabetic Foot Ulcer Grade Classification System is a widely used grading scale for diabetic foot ulcers. It was developed in the 1970s as a treatment guideline to provide direction for the level of surgical intervention. It is easy to use and a good predictor of pending amputation.  The Wagner Scale uses 6 grades ranging from 0-5. The scale assesses depth, presence of osteomyelitis (bone infection) and presence and extent of gangrene in the affected limb. Critics of the Wagner Diabetic Foot Ulcer Classification System agree that it does not address all aspects of the diabetic foot ulcer. It does not address the patient's vascular status or the presence and extent of neuropathy in the affected limb. The presence of venous and/or arterial disease must also be addressed for the patient to fully heal their diabetic foot ulcer and neuropathy must be addressed for the prevention of future diabetic foot ulcers.

The Six Grades of the Wagner System

The Wagner Diabetic Foot Ulcer Classification System uses 6 grades to classify the diabetic wound. 

• Grade 0: There is no open lesion. The skin is intact, but the foot may have deformities, callus build-up or active cellulitis. This grade needs to be reassessed frequently.
• Grade 1: This includes a superficial ulcer with partial or full tissue loss. 
• Grade 2: This wound extends into the ligament, tendon, or joint capsule and includes soft tissue infection. The muscle, bone and joint are not infected at this level.
• Grade 3: This wound also extends into the ligament, tendon or joint capsule however the infection has now progressed to osteomyelitis or bone infection, and or joint sepsis.
• Grade 4: This wound has progressed to gangrene that is localized to the toes or forefoot.
• Grade 5: This wound has progressed to an ulcer with gangrene involving the entire foot and is often beyond salvage.

Why Wagner Classification System

Although there is no universally agreed-upon scale for classifying the diabetic foot ulcer, the Wagner Diabetic Foot Ulcer Grade Classification System does give nurses a tool they need to classify and document on the diabetic foot ulcer. Another crucial factor to remember when using the Wagner Diabetic Foot Ulcer Classification System is that Medicare uses its guidelines for reimbursement for Hyperbaric Oxygen Therapy for patients. Patients with a Grade 3 or higher, according to the Wager Diabetic Foot Ulcer Grade Classification System, would qualify for reimbursement of Hyperbaric Oxygen Therapy as a part of their treatment protocol.  Hyperbaric Oxygen Therapy has been shown, in conjunction with antibiotic therapy and revascularization of the affected limb, to heal the diabetic foot ulcer and prevent amputation. 

Nurses are advocates for patients every day and must stay educated on the tools and systems available for the assessment and treatment of patients. The Wagner Diabetic Foot Ulcer Grade Classification System is one of several classification systems used for diabetic foot ulcers today. It is widely accepted and used throughout the United States.

Resources

Hyperbaric oxygen therapy

Hyperbaric oxygen and wound healing

Understanding Diabetic Foot Ulcer Classification Systems

Diabetic foot ulcers: pathogenesis and management