Paraspinal Muscle Atrophy After Lumbar Spine Surgery.

Paraspinal muscles are commonly affected during spine surgery. The purpose of this study was to assess the potential factors that contribute to paraspinal muscle atrophy (PMA) after lumbar spine surgery. A comprehensive review of the available English literature, including relevant abstracts and references of articles selected for review, was conducted to identify studies that reported PMA after spinal surgery. The amount of postoperative PMA was evaluated in (1) lumbar fusion vs nonfusion procedures; (2) posterior lumbar fusion vs anterior lumbar fusion; and (3) minimally invasive (MIS) posterior lumbar decompression and/or fusion vs non-MIS equivalent procedures. In total, 12 studies that included 529 patients (262 men and 267 women) were reviewed. Of these, 365 patients had lumbar fusions and 164 had lumbar decompressions. There was a significantly higher mean postoperative volumetric PMA with fusion vs nonfusion procedures (P=.0001), with posterior fusion vs anterior fusion (P=.0001), and with conventional fusions vs MIS fusions (P=.001). There was no significant difference in mean volumetric lumbar PMA with MIS decompression vs non-MIS decompression (P=.56). There was significantly higher postoperative PMA with lumbar spine fusions, posterior procedures, and non-MIS fusions.