Stage 1
Risk of amputation
Very low
WIfI spectrum score
W0 I0 fI0,1 W0 I1 fI0 W1 I0 fI0,1 W1 I1 fI 0
Stage 2
Risk of amputation
Low
WIfI spectrum score
W0 I0 fI2 W0 I1 fI1 W0 I2 fI0,1 Wo I3 fI0 W1 I0 fI2 W1 I1 fI1 W1 I2 fi0 W2 I0 fI0/1
Stage 3
Risk of amputation
Moderate
WIfI spectrum score
W0 I0 fI3 W0 I2 fI1,2 W0 I3 fI1,2 W1 I0 fI3 W1 I1 fI2 W1 I2 fI1 W1 I3 fI0,1 W2 I0 fI2 W2 I 1 fI0,1 W2 I2 fi0 W3 I0 fi0,1
Stage 4
Risk of amputation
High
WIfI spectrum score
W0 I1,2,3 fI3 W1 I1 fI3 W1 I2,3 fI2,3 W2 I0 fi3 W2 I1 fI2,3 W2 I2 fi1,2,3 W2 I3 fI0,1,2,3 W3 I0 fI2,3 W3 I1,2,3 fI0,1,2,3

Clinical stage 5 would signify an unsalvageable foot (most often because of wound extent or severity of infection).