Partial foot amputation in patients with diabetic foot ulcers.

BACKGROUND: Transtibial amputations (TTA) are performed for recalcitrant or infected ulcers of the midfoot, hindfoot, or ankle. This procedure results in decreased ambulatory status caused by increased oxygen demands and energy expenditure. Partial foot amputations have the advantage of being an end-bearing limb and require less work to walk, theoretically suggesting improved functional outcome. The purpose of this research was to examine the longevity, outcome, and mortality of partial foot amputations as an alternative to TTA.
METHODS: Retrospective chart review identified diabetic patients with transmetatarsal, Chopart's, and calcanectomy amputations for osteomyelitis or nonhealing ulcers. A control group consisted of diabetic patients who underwent TTA. A comparison between groups examined mortality, proximal ipsilateral reamputation, and a validated ambulatory functional outcome measure.
RESULTS: Eighteen TTA patients were enrolled. The 5-year mortality rate was 0.45, one patient required reamputation, and the mean postoperative ambulatory score was 2.8. Twenty-one transmetatarsal patients were enrolled. The 5-year mortality rate was 0.30, two patients required reamputation, and the mean postoperative ambulatory score was 4.3. Ten Chopart's amputation patients were enrolled. The 5-year mortality rate was 0.36, six patients required reamputation, and the mean postoperative ambulatory score was 4.3. Seventeen partial calcanectomy patients were enrolled. The 5-year mortality rate was 0.69, six patients required reamputation, and the mean postoperative ambulatory score was 4.3. Sixteen total calcanectomy patients were enrolled. The 5-year mortality rate was 0.59, five patients required reamputation, and the mean postoperative ambulatory score was 3.3.
CONCLUSION: TTA is associated with high morbidity and mortality, which suggests that the advantage of partial foot amputations should be investigated. Only transmetatarsal amputations at 1 and 3 years were statistically lower for mortality than TTA. Partial foot amputations at the other levels failed to show statistically improved survivorship. Transmetatarsal and Chopart's amputations had high ambulatory levels and the longest durability, which suggests that these amputations may provide some ambulatory advantage.