Biportal endoscopic spinal surgery for thoracic ossification of the ligamentum flavum: a study of different classification types and surgical outcomes

By
Honggang Wang
Dongqing He
Ruxing Liu
Jie Yuan
Yongfeng Wang
June 5, 2026
0 min

Frontiers In Neurology

Overview

This study evaluates the clinical effectiveness of biportal endoscopic spinal surgery (BESS) for thoracic ossification of the ligamentum flavum (OLF) across different classification types. Both non-fused and fused groups showed significant improvements in clinical outcomes, although the fused group experienced longer operative times and higher complication rates.

Background

Thoracic ossification of the ligamentum flavum (OLF) is a significant cause of thoracic myelopathy, often requiring surgical intervention for neurological recovery. Biportal endoscopic spinal surgery (BESS) has emerged as a minimally invasive option that may reduce complications associated with traditional open laminectomy. Understanding the outcomes of BESS in different OLF classifications can inform surgical decision-making.

Data Highlights

Group	VAS Improvement	mJOA Improvement	APD Increase	CSA Increase	Operative Time	Complications
Non-Fused	Significant	Significant	Less than Fused	Similar	Shorter	Lower
Fused	Significant	Significant	Greater	Similar	Longer	Higher

Key Findings

37 patients underwent BESS for thoracic OLF, divided into non-fused (19) and fused (18) groups.
Both groups showed significant improvements in VAS and mJOA scores postoperatively (p < 0.05).
No significant differences in recovery rates were observed between groups at any postoperative time point (p > 0.05).
The increase in anteroposterior diameter (APD) was significantly greater in the fused group (p < 0.05).
Operative times were longer and complications were more frequent in the fused group compared to the non-fused group.
Careful evaluation is recommended for complex cases, ideally managed by experienced surgeons.

Clinical Implications

The findings suggest that BESS can achieve comparable short-term clinical outcomes for both fused and non-fused thoracic OLF. However, the increased operative time and complication rates in the fused group highlight the need for careful patient selection and surgical expertise.

Conclusion

BESS is a viable surgical option for thoracic OLF, providing significant clinical improvements regardless of OLF classification, though complex cases necessitate experienced surgical management.