A new classification for complex lumbosacral injuries

Abstract

The optimal classification and treatment algorithm for complex lumbosacral injuries, in particular high-energy sacral fractures and lumbosacral dissociation (LSD) injuries, remains controversial. Currently used classification systems are largely descriptive, lacking validity, reproducibility, treatment considerations, and prognostic information. We set out to develop a comprehensive, yet practical, classification system for complex lumbosacral injuries that assists in clinical decision making. We developed a new classification system for complex lumbosacral injuries derived through literature review, expert opinion, and our clinical experience treating combat casualties over the past 10 years. We have seen an increased incidence of complex sacral fractures and LSD injuries after high-energy blast trauma, motor vehicle collisions, and aircraft crashes. We performed an extensive literature review and discussed the proposed classification with spinal trauma surgeons from a variety of institutions familiar with the treatment of complex high-energy sacral fractures and LSD injuries. We identified the significant clinical and radiographic variables encountered in the decision-making process for the treatment of complex lumbosacral injuries. Existing classification systems were reviewed in light of these essential characteristics, and their limitations were defined and addressed with the new system. A new classification system called lumbosacral injury classification system (LSICS) was devised based on three injury characteristics: injury morphology, posterior ligamentous complex integrity, and neurologic status. A composite injury severity score was calculated by summing a weighted score from each category, allowing patients to be stratified into surgical and nonsurgical treatment groups based on threshold values. Modifiers to determining appropriate selection for operative treatment include systemic injury load and physiological status of the polytraumatized patient, soft-tissue status, and expected time to mobility. Finally, an algorithm was developed to determine the optimum operative technique based on the previously outlined injury characteristics. The LSICS provides a comprehensive and practical approach for evaluating injury severity and guiding clinical decision making. This system provides common language for surgeons to communicate various injury patterns and formulate treatment modalities. Further studies are necessary to determine the reliability and validity of this new classification system.