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Joint Diseases and
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Review · Open access

Clinical efficacy and safety of unilateral biportal endoscopy for thoracic ossification of ligamentum flavum: A systematic review

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Jun Li

Department of Orthopaedic, Affiliated Hospital of Southwest Jiaotong University, the Third People’s Hospital of Chengdu, Chengdu, China

ORCID: 0000-0003-3243-317X

Linbo Jiang

Department of Radiology, Affiliated Hospital of Southwest Jiaotong University, the Third People’s Hospital of Chengdu, Chengdu, China

ORCID: 0009-0009-0233-8391

Ting Zhang

Department of General Surgery, Center of Obesity and Metabolic Diseases, Affiliated Hospital of Southwest Jiaotong University, the Third People’s Hospital of Chengdu, Chengdu, China

ORCID: 0000-0003-3473-956X

Abstract

Objectives: In this systematic review, we discuss the clinical efficacy and complications of unilateral biportal endoscopy (UBE) in the treatment of thoracic ossification of the ligamentum flavum (TOLF), providing surgeons with evidence-based guidance for optimal treatment decisions.

Materials and methods: We systematically searched the PubMed, EMBASE, Cochrane Library, CNKI, Wanfang, and VIP databases up to January 2025. Inclusion criteria encompassed studies reporting UBE outcomes for single/double-segment TOLF. Data on pain (Visual Analog Scores [VAS]), function (Oswestry Disability index [ODI] and Japanese Orthopaedic Association [JOA]), and complications were pooled using random-effects models. Minimal clinically important difference (MCID) was applied as the evaluative benchmark for clinical significance.

Results: Six studies (n=77) were analyzed. Significant improvements were observed in leg pain (p<0.001; 95% confidence interval [CI]: –6.63 to –3.57; I2=88%), back pain (p<0.0001; 95% CI: –6.36 to –3.83; I2=86%), ODI (p<0.00001; 95% CI: 31.00 to 53.53; I2=95%), and JOA scores (p<0.05; 95% CI: 2.80 to 3.70; I2=86%). The overall complication rate was 28% (2/6 reporting zero complications), predominantly mild (headache, hyperalgesia). Severe complications included dural tears (2.6%) and spinal cord injury (2.6%), with heterogeneity attributed to surgical technique evolution.

Conclusion: Preliminary evidence suggests UBE may be a promising minimally invasive approach for TOLF, potentially offering accelerated recovery and reduced perioperative morbidity. However, given the limited sample size and substantial heterogeneity, these findings require validation through large-scale prospective studies.

Declarations

Author Contributions

Contributed to the conceptualization and design of the study: J.L., T.Z.; Conducted a systematic literature search and data analysis, contributing significantly to the interpretation of the data: J.L., L.J.; Was responsible for drafting the manuscript and performing the statistical review: J.L.; Provided a critical review of the manuscript and took primary responsibility for the final content: T.Z. All authors reviewed and approved the final version of the manuscript.

Conflict of Interest

The authors declared no conflicts of interest with respect to the authorship and/or publication of this article.

Financial Disclosure

This study was supported by Sichuan Provincial Natural Science Foundation (2024NSFSC1619) and Technological Innovation R&D Project of Chengdu Municipal Science and Technology Bureau (2024-YF05-01281-SN).

Data Sharing Statement

The data that support the findings of this study are available from the corresponding author upon reasonable request.

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