Related Experiment Video
Updated: May 3, 2026
07:12
Laminectomy for the Removal of Thoracic Ossification of the Ligamentum Flavum TOLF Using Ultrasonic and Conventional Osteotomes
Published on: April 21, 2023
4.0K
[Ossification of posterior longitudinal ligament]
Ryuichi Watanabe1, Takeshi Miyamoto
1Department of Orthopaedic Surgery, School of Medicine, Keio University, Japan.
Clinical Calcium
|January 30, 2014
Summary
Ossification of the posterior longitudinal ligament (OPLL) is a spinal condition causing myelopathy. Once thought specific to East Asians, OPLL is now recognized globally as a subtype of diffuse idiopathic skeletal hyperosteosis.
Area of Science:
- Spinal pathology
- Hyperostotic diseases
- Neurology
Context:
- Ossification of the posterior longitudinal ligament (OPLL) is a spinal condition characterized by abnormal bone growth.
- It is a primary cause of cervical myelopathy due to anterior spinal cord compression.
- Historically, OPLL was considered endemic to East Asian populations, particularly Japanese individuals.
Purpose:
- To review the etiology and natural history of Ossification of the posterior longitudinal ligament (OPLL).
- To discuss the evolving understanding of OPLL's geographical distribution and classification.
- To highlight OPLL as a subtype of diffuse idiopathic skeletal hyperosteosis.
Summary:
- Ossification of the posterior longitudinal ligament (OPLL) leads to spinal myelopathy through anterior cord compression.
- First described in 1838, OPLL was initially believed to be exclusive to East Asian populations.
- Current understanding recognizes OPLL as a manifestation of diffuse idiopathic skeletal hyperosteosis, with cases now reported in Europe and the United States.
Impact:
- Broadens the understanding of spinal hyperostotic diseases.
- Increases awareness of OPLL in diverse geographical regions.
- Facilitates earlier diagnosis and management of OPLL-related myelopathy.
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