Table 1-1 SVS WIfI classification: original 6) Table 1-1-1 Wound.

Grade	Ulcer	Gangrene
0	No ulcer	No gangrene
	Clinical description: ischemic rest pain (requires typical symptoms+ischemia grade 3); no wound.
1	Small, shallow ulcer(s) on distal leg or foot; no exposed bone, unless limited to distal phalanx	No gangrene
	Clinical description: minor tissue loss. Salvageable with simple digital amputation (1 or 2 digits) or skin coverage.
2	Deeper ulcer with exposed bone, joint or tendon; generally not involving the heel;	Gangrenous changes limited to digits
	shallow heel ulcer, without calcaneal involvement
	Clinical description: major tissue loss salvageable with multiple (≧3) digital amputations or standard TMA±skin coverage.
3	Extensive, deep ulcer involving forefoot and/or midfoot; deep, full thickness heel ulcer±calcaneal involvement	Extensive gangrene involving forefoot and/or midfoot; full thickness heel necrosis±calcaneal involvement
	Clinical description: extensive tissue loss salvageable only with a complex foot reconstruction or nontraditional TMA (Chopart or Lisfranc);
	flap coverage or complex wound management needed for large soft tissue defect

TMA: Transmetatarsal amputation