Validation of mangled extremity severity score in assessing the need for extremity amputation

Abstract

INTRODUCTION: The decision to either salvage or amputate a mangled extremity poses great challenge to a surgeon.Different scoring systems were therefore developed to aid orthopaedic surgeons in this decision,eitherto contemplate amputation or proceed to salvage a mangled extremity. Of these scoring systems, the mangled extremity severity score (MESS) is mostly used.However,the high predictive accuracy reported by its developers has not been replicated by other authors. This study was carried out to validate the use of this scoring system in Nigeria and by extension, Africa.
PATIENTS MATERIALS AND METHOD:The study was a hospital based prospective descriptive one which studied all patients with mangled extremities that were admitted into the Accident and Emergency room of the Lagos University Teaching Hospital (LUTH), Idi- Araba, from April 2014 to March 2015. Injured patients with mangled extremities were resuscitated and relevant investigations conducted. The MESS was calculated at presentation in the emergency room by two senior doctors in orthopaedic and trauma units (not lower than senior registrar cadres) independently and an average score calculated, rounded up to the nearest positive integer and documented.Type of treatment offered was based on the experience of the managing consultants. Patients' progresses were monitored and functional outcomes documented. All data generated during the study were analysed using Statistical Package for the Social Sciences (SPSS inc. Chicago, Illinois. version 21.0.Year of release - 2012).
RESULTS: Twenty-nine mangled extremities in 27 patients were studied.The male: female ratio was 3.5:1.Age of patients ranged between 21-70 years with a mean age of 39.9 ±12.3years. Nineteen (65.5%) extremities were salvaged while 10(34.5%) were primarily amputated. Average MESS of all mangled limbs reviewed was 8.1+ 2.6 with scores that ranged from 3 to 13. The mean MESS for limb salvage was 7.0 +2.2while that for primary amputation was 10.1+2.0(P value- 0.01).MESS in this study had a sensitivity of 90%,specificity of 47.4%,positive predictive value of 47.4%, negative predictive value of 90%.AUROC in this study was 0.853.The cost of treatment, number of surgeries, and duration of hospital stay were higher in those with Salvaged limbs.The functional outcome for salvaged upper and lower extremities were better than for those whose limbs were amputated.Level of satisfaction was better in the limbs salvaged group than for those who had ablative surgery with statistical significance (P value- .000).
CONCLUSION: This study validated the clinical utility of MESS in predicting the need for amputation in patients with mangled extremity injuries but it had a low predictive accuracy for extremities that would eventually enter the limb salvage pathway.Therefore,when contemplating limb salvage for a patient with mangled extremity,in addition to the result of the MESS score,the surgeons experience cannot be overemphasized.

KEY WORDS: Open fracture,mangled limb,amputation,MESS score,classification