Endoscopic Decompression of Thoracic Myelopathy Due to Thoracic Ossification of the Posterior Longitudinal Ligament (OPLL) and Ossification of the Ligamentum Flavum (OLF)

Thoracic ossification of the posterior longitudinal ligament (OPLL) and ossification of the ligamentum flavum (OLF) are major causes of thoracic myelopathy, particularly in East Asian populations. Traditional surgical management often requires extensive open procedures that carry significant morbidity. Recent advancements in minimally invasive spine surgery have enabled safe and effective decompression using uniportal or biportal endoscopic techniques. This chapter provides an in-depth overview of thoracic OPLL and OLF, covering pathoanatomy, indications, and surgical planning, with the primary focus on biportal endoscopic decompression. Clinical evidence suggests that these techniques result in favorable neurological outcomes, reduced complication rates, and faster recovery compared to conventional approaches. Key technical considerations, complication management, and tips for improving safety are also discussed. Our surgical technique outlines a step-by-step approach to posterior decompression, with emphasis on safe drilling zones, dura-sparing dissection, and hemostatic control. Endoscopic thoracic surgery offers a reproducible and less invasive solution for managing thoracic myelopathy caused by ligamentous ossification.