SEVERE OPEN FRACTURES OF THE LOWER-EXTREMITY - A RETROSPECTIVE EVALUATION OF THE MANGLED EXTREMITY SEVERITY SCORE (MESS)

Recent reports using the Mangled Extremity Severity Score (MESS) sugge st that a score of greater-than-or-equal-to 7 is 100% accurate in pred icting the need for amputation of severely injured lower extremities. To further evaluate the value of the MESS in predicting amputation, sp ecifically with respect to type IIIB and type IIIC (Gustilo and Anders on) open fractures of the tibia, we retrospectively evaluated 24 patie nts with these injuries. A significant difference (p = 0.001) between MESS values of 13 salvaged (6.36 +/- 0.35 SEM) and 11 amputated limbs (6.36 +/- 0.54 SEM) was found. A MESS value of greater-than-or-equal-t o 4 was most sensitive (100%); a MESS value of greater-than-or-equal-t o 7 was most specific, and a MESS value of greater-than-or-equal-to 7 was found to have a positive predictive value of 100%. Subsequently, w e addressed recent criticisms of the MESS by including nerve injury in the scoring system and by separating soft-tissue and skeletal injury components of the MESS. We modified the MESS with a score called the N ISSSA and applied it retrospectively to our cases. After careful stati stical comparison we found both the MESS and NISSSA to be highly accur ate (p < 0.005) in predicting amputation. The NISSSA was found to be m ore sensitive (81.8% versus 63.6%) and more specific (92.3 versus 69.2 %).