In an attempt to lower current rates of amputation due to diabetic foot ulcers, the foot care interest group of the American Diabetes Association has published updated management guidelines. Andrew Boulton, MD, FRCP, Manchester Diabetes Center, Manchester, UK, and a co-chair of the Comprehensive Diabetic Foot Exam (CDFE) task force, reviewed these literature-based recommendations.

“To talk about prevention, we need to talk about causality,” began Dr. Boulton, “and 80% of all amputations are preceded by foot ulcers.” Of the preconditions for this type of wound, neuropathy is the most salient component. However, for an ulcer to form, a triad of conditions is commonly present: neuropathy, deformity, and trauma (Reiber et al. Diabetes Care 1999).

Identifying the At-Risk Foot

The most prevalent risk factors that were identified by the CDFE include neuropathy, peripheral vascular disease, prior ulceration, foot deformity, and prior amputation. A new and profound addition to this list is end-stage renal disease; recent data suggest that up to 40% of dialysis patients have past or current ulceration (Game et al. Nephrol Dial Transplant 2006).

A careful general exam, including patient history, will reveal the majority of the aforementioned risks, though neuropathy remains a primary concern, because it may not be readily detected or even be a noticeable cause of concern to the patient. The recommended techniques for the detection of neuropathy are the use of monofilaments (MFs), vibration, pin prick, ankle reflexes, and quantitative sensory testing (eg, biothesiometer).

MFs are the most widely used diagnostic tool and have a proven track record but also have several drawbacks: the issue of accuracy if the MFs buckles at 10 g, an uncertainty about how many sites to test, and the time-consuming nature of the procedure.

CDFE recommendations for neuropathy assessment (or loss of sensory protection; LOPS) are as follows:

• 10 g monofilament tested at 4 sites (MTH 1, 3, and 5 and hallux plantar)

In conjunction with one of the following:

• 128 Hz tuning fork vibration (hallux)

• pin prick sensation (dorsal hallux)

• ankle reflexes

• vibration perception threshold

The foot should then be assessed for healthy vasculature (peripheral artery disease; PAD), and if any pulse is absent, further investigation with an ankle brachial index is warranted.

Follow-up based on stratified risk is recommended:

Finally, Dr. Boulton highlighted several recent studies that have investigated inflammation as a precursor to ulceration and heat as a signature of the presence of inflammation (Lavery et al. Diabetes Care 2007; Armstrong et al. Am J Med 2007). These investigations show that an increase in foot temperature correlates to more than a 3-fold increase in the risk of ulceration. Several instruments are now available that can be used by the patient for self-monitoring of foot temperature, including the handheld TempTouch® and TempStat, a liquid crystal pad that the patient stands on.