Paraspinal Muscle Functional Cross-Sectional Area Alterations in Single-Level Open and Minimally Invasive...

Area of Science:

• Spine surgery outcomes
• Minimally invasive spine techniques
• Muscle physiology in spinal fusion

Background:

• Paraspinal muscle atrophy negatively impacts outcomes after lumbar spine surgery.
• Minimally invasive surgical approaches may mitigate muscle damage.
• Quantifying muscle changes and their clinical relevance is crucial for surgical decision-making.

Purpose of the Study:

• Compare functional cross-sectional area (FCSA) of paraspinal muscles between open transforaminal lumbar interbody fusion (Open-TLIF) and minimally invasive TLIF (MIS-TLIF).
• Assess the correlation between paraspinal muscle changes (FCSA) and clinical outcomes, including Visual Analogue Scale (VAS) for pain and Oswestry Disability Index (ODI).

Main Methods:

• Retrospective cohort study of 129 patients undergoing single-level TLIF.
• Computed tomography (CT) was used to measure FCSA of multifidus, erector spinae, and psoas muscles.
• Correlation and regression analyses examined relationships between FCSA changes, surgical technique, and clinical outcomes.

Main Results:

• Open-TLIF resulted in greater reductions in multifidus and erector spinae FCSA compared to MIS-TLIF.
• MIS-TLIF patients reported lower lumbar VAS and ODI scores post-surgery.
• Multifidus FCSA loss correlated with worse pain and disability; MIS-TLIF was associated with multifidus preservation.

Conclusions:

• MIS-TLIF demonstrates superior paraspinal muscle preservation and better clinical outcomes (reduced pain, improved function) versus Open-TLIF.
• Preservation of the multifidus muscle is a significant predictor of clinical improvement after lumbar fusion.
• Increased psoas FCSA is linked to better disability outcomes, while erector spinae FCSA shows a negative correlation.