A new system for scoring the severity of foot ulcers in diabetic patients helps predict the likelihood of healing, hospitalization, local surgery, and amputation, according to Dr. Stefan Beckert and his associates at the University of Tübingen (Germany).
Although other researchers have made attempts to establish classification systems that help gauge the severity of foot ulcers, most have been too complicated for widespread clinical application. Some systems required extensive work-ups and complex grading schedules, and no simple severity scores have been adopted into routine clinical practice, the investigators said.
Dr. Beckert and his associates followed 1,000 consecutive diabetic patients with foot ulcers to develop such a score, which they termed the Diabetic Ulcer Severity Score (DUSS), and to test its practical use in predicting outcomes.
The median subject age was 69 years, and subjects were followed for up to 1 year after presenting for outpatient foot ulcer care. Treatment was given by an interdisciplinary team of a general and vascular surgeon, a radiologist, a diabetologist, an orthotist, and a wound care nurse. It consisted of sharp debridement, advanced local surgery such as limited bone resections if necessary, moist wound therapy, and adequate pressure off-loading.
Four factors—pedal pulses, bone involvement, site of ulceration, and number of ulcerations—were found to predict outcome, and a simple scoring system was developed to rate these factors, the investigators said (Diabetes Care 2006;29:988–92).
Absent pedal pulses were scored as 1, while present pedal pulses were scored as 0. Bone involvement, defined as the ability to probe the ulcer to the bone, was scored as 1, lack of bone involvement, a 0. Ulceration was scored as 0 if it involved only the toe; 1 if it involved the foot. Multiple wounds were scored as 1 while single wounds were scored as 0.
The overall DUSS was determined by adding these four components, so possible scores ranged from 0 to 4.
Patients with a DUSS of 0 had a 93% probability of healing. The probability of healing decreased steadily with increasing DUSS, to a low of 57% for scores of 4.
Local surgery was required for 9% of patients with a DUSS of 0, 17% of those with a DUSS of 1, 27% for those with a score of 2, 37% for those with a DUSS of 3, and 50% of those with a DUSS of 4. Similarly, hospitalization was required for 39% of patients with a DUSS of 0, 49% of those with a DUSS of 1, 63% of those with a DUSS of 2, 72% of those with a DUSS of 3, and 92% of those with a DUSS of 4.
The likelihood of amputation followed this same pattern for the most part. Patients with a DUSS of 0 had no risk of amputation, those with a DUSS of 1 had a 2% risk, those with a DUSS of 2 had an 8% risk, and those with a DUSS of 3 had an 11% risk. However, the pattern did not hold for patients with a DUSS of 4 (4% risk), most likely because of the small number of patients in this subgroup and the low number of amputations overall, the researchers said.