Mangled Extremity Severity Score (MESS)

Mangled Extremity Severity Score (MESS) Johansen 1990

Combined vascular and orthopaedic injuries.

Used to select lower-extremity injuries that warrant primary amputation.

Vascular injury was never clearly defined in the MESS scoring system, and the MESS score allows for evaluation of patients with normal perfusion. For this reason, the MESS has been widely referenced as the trauma limb-salvage index for lower-extremity trauma.

Four characteristics related to injury:

• Injury severity (energy transfer)
• Ischemia
• Shock
• Age.

Retrospective, study of 25 patients. The index was then validated in that same patient group and prospectively in an additional 26 limbs.

Johansen et al. concluded that a MESS score of 7 or more was 100% predictive of amputation.

Bosse et al in their prospective study found a sensitivity of the MESS was 46%, this increased to 72% if only the ischemic limbs were considered. No advantage was noted in the application of the MESS to any of the nonischemic-limb subgroups. The sensitivity decreased to 27% when the immediate amputations were excluded from the analysis. The sensitivity of the MESS in the cohort of the severely open tibial fractures was 45% overall but was only 22% when the immediate amputations were excluded. The area under the curve for the limbs with a type-IIIC tibial fracture indicated a poor discriminative ability of the index, regardless of whether the immediate amputations were included or excluded (0.62 and 0.68, respectively).

• Generally, the MESS was highly specific, suggesting that it might be useful in predicting the limbs that should not undergo amputation. The low sensitivity, however, suggests that a large proportion of limbs eventually requiring amputation would be at risk for a delay in the procedure, and this delay might in turn be associated with complications.
  
  
  Skeletal / soft-tissue injury 
       Low energy (stab; simple fracture; pistol gunshot wound): 1 
       Medium energy (open or multiple fractures, dislocation): 2 
       High energy (high speed MVA or rifle GSW): 3 
       Very high energy (high speed trauma + gross contamination): 4 
  Limb ischemia 
       Pulse reduced or absent but perfusion normal: 1* 
       Pulseless; paresthesias, diminished capillary refill: 2 
       Cool, paralyzed, insensate, numb: 3* 
  Shock 
       Systolic BP always > 90 mm Hg: 0 
       Hypotensive transiently: 1 
       Persistent hypotension: 2 
  Age (years) 
       < 30: 0 
       30-50: 1 
       > 50: 2 
  
  * Score doubled for ischemia > 6 hours