Maintaining Sagittal Balance When Performing Lumbar Fusion Surgery

Abstract

become one of the hottest topics in spine surgery over recent years. It is widely understood that, to achieve the best functional outcome, sagittal alignment must be considered both when initially evaluating a patient and when deciding upon a surgical intervention. Of all the measurable spinal parameters available, restoration of sagittal alignment has most reproducibly been associated with improved patient-reported functional outcomes. The implications of this are significant for both patients and surgeons alike, as the specific impact of surgery on sagittal balance varies greatly among different procedures, and the end effect is not easily undone. According to an analysis of the national inpatient sample reviewing trends in lumbar fusion procedures from 2004 to 2015 by Martin et al., the volume of elective lumbar fusions has increased more than 62.3% over this time. The greatest increases were seen in patients being treated for lumbar spondylolisthesis and scoliosis, and degenerative lumbar spondylosis, posttraumatic kyphosis, and lumbar stenosis with instability. Although technological advances and access to care are responsible for some of these numbers, a main driving force behind increases in lumbar fusion for diagnoses other than scoliosis is likely the fact that the population of the developed world is progressively getting older. As the average life expectancy increases, so does the proportion of aged patients who are likely to seek surgical treatment for symptomatic degenerative disease of the spine. The responsibility falls on spine surgeons to select the most appropriate surgical or nonsurgical interventions for such patients on an individualized basis. This article serves primarily to address the importance of taking sagittal alignment into account when making these decisions and to provide strategies to maintain spinopelvic harmony.