Postoperative Changes in Paraspinal Muscle Volume: Comparison between Paramedian Interfascial and Midline Approaches for Lumbar Fusion

Abstract

In this study, we compared the paramedian interfascial approach (PIA) and the traditional midline approach (MA) for lumbar fusion to determine which approach resulted in the least amount of postoperative back muscle atrophy. We performed unilateral transforaminal posterior lumbar interbody fusion via MA on the symptomatic side and pedicle screw fixation via PIA on the other side in the same patient. We evaluated the damage to the paraspinal muscle after MA and PIA by measuring the preoperative and postoperative paraspinal muscle volume in 26 patients. The preoperative and postoperative cross-sectional area, thickness, and width of the multifidus muscle were measured by computed tomography. The degree of postoperative paraspinal muscle atrophy was significantly greater on the MA side than on the contralateral PIA side (-20.7% and -4.8%, respectively, p<0.01). In conclusion, the PIA for lumbar fusion yielded successful outcomes for the preservation of paraspinal muscle in these 26 patients. We suggest that the success of PIA is due to less manipulation and retraction of the paraspinal muscle and further studies on this technique may help confirm whether less muscle injury has positive effects on the long-term clinical outcome.

A comparison of the Wiltse versus midline approaches in degenerative conditions of the lumbar spine

“…There are many other studies that demonstrate much greater injury to the surrounding tissues with a midline approach. 6,15 This is possibly the start of the cascade that leads to a greater incidence of adjacent segment pathology with the midline approach, which our data support. Also, a more lateral pedicle screw entry point has a much lower incidence of violating the adjacent facet and capsule of the caudal level.…”

Clinical outcome of microscopic lumbar spinous process–splitting laminectomy

“…11 To estimate postoperative back muscle atrophy, several clinicians have performed quantitative analysis of a cross-sectional area of the paravertebral muscles on pre-and postoperative T2-weighted axial MR images. 5,13,20 We, however, employed semiquantitative analysis using T1-and T2-weighted axial MR images to assess fat infiltration or edematous change in the multifidus muscle, reflecting even minor muscular degeneration, especially after minimally invasive surgery. 11,12,16 Compared with the tubular retractor, the cervical retractor tends to cause increased muscle degeneration because the cervical retractor stretches the back muscle with more compressive force than does the tubular retractor.…”

Quality of life and disability: can they be improved by active postoperative rehabilitation after spinal fusion surgery in patients with spondylolisthesis? A randomised controlled trial with 12-month follow-up

“…In these patients, the chronic low back pain may have affected the muscle functioning [4] and cardiorespiratory fitness [5]. In addition, fusion surgery itself leads to changes in spinal function [6][7][8][9].…”