Step 3: Measure (and grade) the wound
Accurate measurement of ulcer size is critical, both when you initially detect it and at each subsequent visit. To get an accurate measure, simply multiply the greatest length by the greatest width. The percent change in wound size after 4 weeks of treatment is a significant predictor of healing.25
Some clinicians also use photographs to track wound size, but these can be misleading. A better approach is to trace the wound on a sheet of acetate to document progress over time. If you see no improvement within 2 weeks, treatment should be modified.
Use a grading tool. There are a number of systems used for grading ulcers, none of which is universally accepted. One well-known tool is the Wagner Classification System16 (TABLE 2) referred to earlier. The higher the grade, the lower the likelihood that the ulcer will heal.
TABLE 2
Grading the ulcer: The Wagner system
| Grade | Description |
|---|---|
| 0 | No open lesions; may have deformity or cellulitis |
| 1 | Superficial diabetic ulcer (partial or full thickness) |
| 2 | Ulcer extension to ligament, tendon, joint capsule, or deep fascia (without abscess or osteomyelitis) |
| 3 | Deep ulcer with abscess, osteomyelitis, or joint sepsis |
| 4 | Gangrene localized to portion of forefoot or heel |
| 5 | Extensive gangrenous involvement of the entire foot |
| Adapted from: Wagner FW Jr. Orthopedics. 1987.16 | |
Step 4: Debride the ulcer
Frequent sharp debridement—to remove necrotic, callused, infected, and hypergranulation tissue—has long been considered essential in the treatment of neuropathic ulcers,17,21 especially for chronic or infected wounds. Debridement is thought to aid in healing by reducing pressure on the ulcer, decreasing bacterial contamination, enhancing platelet activation, releasing growth factors, and stimulating granulation tissue.
While some physicians are hesitant to perform debridement in the office, the process can actually be carried out without difficulty in an outpatient setting. Because of the neuropathy associated with most diabetic ulcers, no anesthesia is required. While the procedure is not typically painful, you will need to provide patient education to prepare the patient for the possibility of bleeding. Debride the wound to the outer edge of the hyperkeratotic tissue. If bleeding occurs, simply apply pressure until it stops.
When not to debride. Debridement is contraindicated under certain circumstances—if the limb has poor circulation, for example. Similarly, avoid debriding heel ulcers covered by eschar if there is no fluctuance in the underlying tissue, as the eschar provides a protective barrier.24 When sharp debridement is not possible, consider topical hydrogel or maggot therapy, an adjuvant treatment we’ll discuss in a bit.
Step 5: Off-load the wound
Mechanical load relief is vital for treating neuropathic ulcers, both to redistribute plantar pressures and protect granulation tissue. Total contact casting (TCC) is the gold standard, healing 90% of ulcers within 6 to 8 weeks.28 TCC is costly when applied weekly, however, and should only be done by a specialist, as an incorrectly applied cast can lead to the creation of new ulcers.
Because of the heaviness and inconvenience of the casts, many patients prefer removable devices, but these devices are much less effective. One study found that the average removable off-loading device is worn no more than 30% of the time that the patient is walking.29 Removable devices can be temporarily secured with plaster of Paris (a process that is sometimes referred to as instant contact casting) to ensure compliance.
Acceptable removable devices include a heel pressure relief shoe for heel ulcers and a CAM (controlled ankle motion) walker for metatarsal ulcers. Be sure off-loading devices are applied securely so no slippage can occur.
Step 6: Cover with moist dressings
The purpose of any topical dressing is to keep wounds moist, absorb exudate, and prevent contamination. A variety of moist dressings have been successfully used to treat ulcers, although evidence to recommend any particular dressing is insufficient.19 While wound vacuum-assisted closure (VAC) devices are widely used, there is little support for their use. A review of 7 trials comparing VAC devices with moistened gauze dressings or other topical agents found no evidence that topical negative pressure increases chronic wound healing.30
When foot ulcers do not heal
AIM DOC highlights the steps of diabetic ulcer care that are most likely to result in healing. When ulcers are slow to heal, review the 6 steps of treatment, paying particular attention to off-loading. If you establish that these have been appropriately applied and the wound is still not responding, consider alternative diagnoses such as venous insufficiency, vasculitis, or malignancy. Venous insufficiency ulcers may be difficult to differentiate from neuropathic ulcers, but they won’t heal without compression dressings. Diagnosis of vasculitis and malignancy can be made by biopsying the ulcer edge.