Inclusion Criteria:  No surgical treatment was performed before the imaging scan. Imaging report and clinical diagnosis of cervical spondylosis with or without ossification of the posterior longitudinal ligament. Patients who visited the orthopedics department and emergency department of our hospital without any surgical treatment before image scan and no obvious abnormalities were found in cervical imaging CT.  Exclusion Criteria:  Surgery before image data acquisition; Cervical cancer, tuberculosis, and fracture; The lack of image data, the image is not clear.