1. Copyright © 2012 Lippincott Williams & Wilkins. Unauthorized commercial reproduction of this slide is prohibited Supplemental PowerPoint Slides Analysis of Radiography Findings of Ossification of Nuchal Ligament of Cervical Spine in Patients with Cervical Spondylosis Hongli Wang, MD, Fei Zou, MD, Jianyuan Jiang*, MD, Feizhou Lu, PhD, Wenjun Chen, MD, Xiaosheng Ma, PhD, Xinlei Xia, PhD, Lixun Wang, PhD Department of Orthopaedics, Huashan Hospital, Fudan University, Shanghai 200030, China

2. Copyright © 2012 Lippincott Williams & Wilkins. Unauthorized commercial reproduction of this slide is prohibited Supplemental PowerPoint Slides The incidence of ONL is 49.7% in patients with cervical spondylosis, which is higher than normal Asian according to previous studies. Gender, age, and OPLL are related factors of ONL.

3. Copyright © 2012 Lippincott Williams & Wilkins. Unauthorized commercial reproduction of this slide is prohibited Supplemental PowerPoint Slides ONL could be classified into five types through morphology on the plain radiography: local, continuous, segmental, mixed and unclassified. Local type is the most common type of ONL, and multi-level ONL occurs mostly in patients with OPLL. TYPEDESCRIPTION Local Point-shaped ONL, and the length is shorter than the anterior vertebrae Conti nuous Continuous rod-shaped ONL, and the length is longer than the anterior vertebrae Segm ental Discontinuous ONL, and the shape of separated parts are similar Mixed The ossification consists of types mentioned above Uncla ssified The shape of the ossification is complex, and it is not consistent with the types mentioned above

4. Copyright © 2012 Lippincott Williams & Wilkins. Unauthorized commercial reproduction of this slide is prohibited Supplemental PowerPoint Slides C4,5 and C5,6 are the segments where ONL occurs mostly.