The efficacy of laminoplasty and laminectomy with fusion for ossification of the posterior longitudinal ligament with high occupation rate in the cervical spine is not clear in the literature report so far. This study is designed to further research the difference in efficacy between the two surgical methods.

Ossification of the posterior longitudinal ligament(OPLL) is a common spinal disease which can lead to neurological dysfunction and its morbidity is related to genetic factors. OPLL is usually found in cervical spine and characterized by hypertrophy and ossification of the posterior longitudinal ligament in the rear of the corresponding cervical vertebral body, which can encroach the space in the spinal canal and compress the spinal cord and/or nerve roots of the corresponding segments, resulting in sensory and motor disorders of the limbs as well as visceral autonomic nervous dysfunction, leading to neurological dysfunction and even high paraplegia. It not only causes great harm but also brings heavy economic and spiritual burden to patients and society.

Although the surgical treatments for OPLL include anterior and posterior approach, the anterior approach requires excellent equipment and rich operation experience for surgery doctor. Many articles showed significantly higher complications rate in anterior approach than that of posterior approach. Posterior approach surgery is considered to be one of the effective treatment methods for OPLL in cervical spine. In the posterior approach, there are two commonly recognized surgical procedures, laminoplasty and laminectomy with fusion. The efficacy of laminoplasty and laminectomy with fusion for ossification of the posterior longitudinal ligament with high occupation rate in the cervical spine is not clear in the literature report so far. This study is designed to further research the difference in efficacy between the two surgical methods. The purpose of this study is to make patients get the biggest medical benefits and to make a right surgical treatment strategy when doctors treating patients with high occupation rate OPLL in cervical spine.

Inclusion Criteria:

• Patients diagnosed by clinical symptoms, physical examination, X-ray, CT, and MRI with a high occupation rate of ossification of the posterior longitudinal ligament in the cervical spine need and can be treated surgically after preoperative examination.
• CT axial soft tissue window determine that the occupation rate of one or more spinal canal segments in C2-7 is more than 60%.
• Sagittal CT show ossification of more than 3 segments of the posterior longitudinal ligament of the cervical spine.
• Sign the written informed consent

Exclusion Criteria:

• Participating in other interventional clinical trials;
• Mental disorders or cognitive disorders;
• Heart and lung diseases;
• Nervous system diseases;
• Patients with serious liver and kidney diseases, tumors and infectious diseases;
• There are any other factors that the treated doctors consider unsuitable for inclusion or completion of the study.
• Patients with cervical spondylotic radiculopathy
• Patients with severe osteoporosis, skeletal fluorosis and other reasons for which laminoplasty is not feasible
• Patients with ossification of posterior longitudinal ligament of cervical spine with invasion rate ≥60% had cervical trauma
• The patient with cervical ligamentum flavum ossification was diagnosed at the C2-7 level
• Preoperative pregnancy test was performed to exclude pregnant women