Spine surgeons frequently evaluate the clinical benefits of MIS-TLIF vs Open-TLIF during surgical planning and decision-making. This choice significantly affects the long-term health of the paraspinal muscles. Therefore, understanding muscle changes helps clinicians predict patient recovery and functional success. For example, preserving the multifidus muscle often leads to better spinal stability and movement. Consequently, researchers conducted a retrospective cohort study to analyze functional cross-sectional area (FCSA) changes and patient outcomes after surgery.

Impact of MIS-TLIF vs Open-TLIF on Muscle Atrophy

Indeed, the study followed 129 patients for at least one year to ensure accurate results. Specifically, the team compared 60 Open-TLIF patients with 69 MIS-TLIF patients. Furthermore, they used computed tomography (CT) to measure muscle areas at the index and adjacent levels. Specifically, they looked at the multifidus, erector spinae, and psoas muscles. Because Open-TLIF requires more extensive muscle dissection, it often causes greater tissue trauma and scarring. In contrast, MIS-TLIF utilizes smaller incisions and muscle-splitting techniques. Thus, MIS-TLIF patients showed significantly less muscle loss at both the index and adjacent levels compared to the open approach.

Moreover, the degree of muscle preservation directly impacts how a patient recovers after the procedure. Notably, Open-TLIF patients experienced significantly greater reductions in the index multifidus and erector spinae muscles. Consequently, these patients reported higher pain levels and slower recovery. Specifically, a loss in the index multifidus FCSA correlated with worse scores on the Visual Analogue Scale (VAS) and Oswestry Disability Index (ODI). Therefore, preserving muscle mass remains an essential goal for reducing postoperative disability. Subsequently, the study data suggest that minimally invasive techniques offer superior functional outcomes for most patients.

Additionally, surgeons must consider the health of muscles at adjacent levels when performing lumbar fusion. Because muscle health affects the entire lumbar segment, extensive atrophy can lead to adjacent segment disease or persistent instability. Nevertheless, MIS-TLIF effectively maintained the cross-sectional area of nearby muscles during the follow-up period. So, patients recovered faster and faced fewer functional limitations in their daily lives. Overall, these findings highlight why the choice of surgical technique is paramount for long-term health. Finally, clinicians should prioritize muscle-sparing approaches like MIS-TLIF to ensure the best possible patient experience.

Frequently Asked Questions

How does MIS-TLIF vs Open-TLIF affect paraspinal muscles differently?

Open-TLIF often involves significant muscle stripping and retraction, which causes more atrophy and scarring. In contrast, MIS-TLIF uses a muscle-splitting approach with tubular retractors that preserves the functional cross-sectional area of the multifidus and erector spinae.

Why is the functional cross-sectional area (FCSA) important after spine surgery?

The FCSA represents the healthy, contractile part of the muscle. Because a higher FCSA correlates with lower pain levels and better mobility, preserving this area is vital for reducing disability and improving the Oswestry Disability Index (ODI) scores after surgery.

Disclaimer: This content is for informational and educational purposes only. It is not intended as medical advice or a substitute for professional healthcare. Refer to the latest local and national guidelines for clinical practice.

References

1. Maharjan S et al. Paraspinal Muscle Functional Cross-Sectional Area Alterations in Single-Level Open and Minimally Invasive Transforaminal Lumbar Interbody Fusion: A Correlational Analysis. Clin Spine Surg. 2026 Feb 13. doi: 10.1097/BSD.0000000000002044. PMID: 41686480.

2. Fan S, Hu Z, Zhao F, Zhao X, Huang Y, Fang X. Multifidus muscle changes and clinical effects of one-level posterior lumbar interbody fusion: minimally invasive procedure versus conventional open approach. Eur Spine J. 2010;19(2):316-324. doi:10.1007/s00586-009-1149-z.

3. Kim DY, Lee SH, Chung SK, Lee HY. Comparison of multifidus muscle atrophy and clinical outcome after minimally invasive and open lumbar interbody fusion. J Korean Neurosurg Soc. 2005;38:186-191.