summary Ossification Posterior Longitudinal Ligament is an idiopathic cervical spine anomaly that is a common cause of cervical myelopathy in the Asian population. Diagnosis is made with lateral radiographs of the cervical spine. CT scan is the study of choice to determine the extent and thickness of the ossification. Treatment is observation in patients with minimal symptoms. Surgical decompression followed by stabilization is indicated for patients with myelopathy. Epidemiology Demographics Asian most common in but not limited to men > women Anatomic location most common levels are C4-C6 95% of ossification is located in C spine Etiology Pathophysiology cause is unclear but likely multifactorial associated factors diabetes obesity high salt-low meat diet poor calcium absorption mechanical stress on posterior longitudinal ligament Presentation Symptoms often asymptomatic symptoms and exam findings consistent with symptoms of myelopathy Physical exam findings of myelopathy Imaging Radiographs lateral radiograph often shows ossification of PLL important to evaluate sagittal alignment of cervical spine MRI study of choice to evaluate spinal cord compression CT study of choice to delineate bony anatomy of ossified posterior longitudinal ligament Treatment Nonoperative observation indicated only in patient with mild symptoms who are not candidates for surgery Operative direct or indirect surgical decompression followed by stabilization indications indicated in most patients with significant symptoms Techniques Interbody fusion without decompression indications in patients with dynamic myelopathy technique theory behind technique is that by removing motion at stenotic levels trauma to the cord is eliminated Anterior corpectomy with or without OPLL resection indications indicated in patient with kyphotic cervical spine where posterior decompression is not an option technique one method to avoid a dural tear is to perform a corpectomy, and instead of removing the OPLL from the dura, allow it to "float" in the corpectomy site Posterior laminoplasty or laminectomy with fusion indications only effective in lordotic spine as it allows the spinal cord to drift away from the anterior compression of the OPLL considered a safer and preferable approach due to the difficulty of resecting the OPLL off the dura from an anterior approach techniques fusion should be performed with laminectomy to avoid post-laminectomy kyphosis complications there is a risk of postoperative OPLL growth Complications Recurrence of OPLL recurrance reduced with complete resection leaving OPLL to float in corpectomy site