Back Muscle Morphometry: Effects on Outcomes of Spine Surgery.

Abstract

This review seeks to synthesize emerging literature on the effects of back muscle size on outcomes in spine surgery. Risk factors that contribute to poor surgical outcomes continue to be an area of interest in spine surgery because proper risk stratification can result in reduction in morbidity and enhanced patient care. However, the impact of muscle size on spine surgical outcomes is an understudied avenue with paucity of data evaluating the relationship among back muscles and surgical outcomes, patient's quality of life, and functional improvement postoperatively. This review was centered around identifying studies that assessed the impact of back muscle size on spine surgery outcomes. Five retrospective studies were selected for review. All studies set out to see if differences in muscle size existed in patients with disparate post-operative outcomes as a primary objective. The studies support the association between larger back muscles and improved outcomes. The size and relative cross sectional area of paraspinal muscles and the size of the psoas muscle were associated with functional outcomes, incidence of complications and also fusion rates. With reduction in surgical complications and improvement in postoperative functional outcomes, back muscle morphometry ought to be included in the preoperative surgical planning as a predictor of outcomes.