From: Frostbite: a practical approach to hospital management
Frostbite injuries of the extremity | Grade 1 | Grade 2 | Grade 3 | Grade 4 |
---|---|---|---|---|
Extent of initial lesion at day 0 after rewarming | Absence of initial lesion | Initial lesion on distal phalanx | Initial lesion on intermediary (and) proximal phalanx | Initial lesion on carpal/tarsal |
Bone scanning at day 2 | Useless | Hypofixation of radiotracer uptake area | Absence of radiotracer uptake on the digit | Absence of radiotracer uptake area on the carpal/tarsal region |
Blisters at day 2 | Absence of blisters | Clear blisters | Haemorrhagic blisters on the digit | Haemorrhagic blisters over carpal/tarsal region |
Prognosis at day 2 | No amputation | Tissue amputation | Bone amputation of digit | Bone amputation of the limb |
No sequelae | Fingernail sequelae | Functional sequelae | +/− systemic involvement | |
 |  |  |  | +/− sepsis functional sequelae |