A — Skeletal and Soft Tissue Injury Severity

Low energy — stab wound, simple fracture, civilian low-velocity gunshot wound+1Medium energy — open or multiple fractures, dislocations, moderate crush+2High energy — close-range shotgun, military GSW, high-energy crush injury+3Very high energy — gross contamination, soft tissue avulsion, degloving with periosteal stripping+4

B — Limb Ischemia (score is DOUBLED if ischemia duration > 6 hours)

No ischemia — pulse normal, no vascular deficit (0 pts)+0Mild ischemia, ≤6h — reduced/absent pulse, paresthesias, mild capillary delay (1 pt)+1Mild ischemia, >6h — same as above but ischemia >6h (doubled: 2 pts)+2Moderate ischemia, ≤6h — absent pulse, paresthesias, motor weakness, cool limb (2 pts)+2Moderate ischemia, >6h — absent pulse, weakness, cool limb, ischemia >6h (doubled: 4 pts)+4Severe ischemia, ≤6h — pulseless, insensate, paralyzed, ashen/cool limb (3 pts)+3Severe ischemia, >6h — pulseless, insensate, paralyzed, limb threatened >6h (doubled: 6 pts)+6

C — Hemodynamic Shock

Normotensive — SBP ≥ 90 mmHg throughout (no significant hemodynamic compromise)+0Transient hypotension — SBP < 90 mmHg briefly, responds to initial resuscitation+1Persistent hypotension — SBP < 90 mmHg persisting despite initial resuscitation attempts+2

D — Patient Age

Age < 30 years (best physiologic reserve)+0Age 30–50 years+1Age > 50 years (reduced physiologic reserve and healing capacity)+2

Mangled Extremity Severity Score (MESS)

Mangled Extremity Severity Score (MESS)