Odontoid incidence: a constant cervical anatomical feature evident in standing plain radiographs and supine magnetic resonance images

• Published in: Journal of orthopaedic surgery and research Vol. 19; no. 1; pp. 63 - 8
• Main Authors: Huang, Longao, Chen, Weiyou, Xu, Hongyuan, Qin, Hongyu, Jiang, Hua
• Format: Journal Article
• Language: English
• Published: England BioMed Central Ltd 13.01.2024; BioMed Central; BMC
• Subjects: Agreements; Back surgery; C2 slope; Cervical sagittal parameters; Cervical Vertebrae - diagnostic imaging; Cervical Vertebrae - pathology; CL prediction; Comparative analysis; Disease; Humans; Lordosis - diagnostic imaging; Magnetic Resonance Imaging; Odontoid incidence; Odontoid Process - diagnostic imaging; Odontoid tilt; Orthopedics; Quality of life; Radiography; Retrospective Studies; X-rays; Odontoid incidence; C2 slope; Cervical sagittal parameters; CL prediction; Odontoid tilt
• DOI: 10.1186/s13018-024-04542-0
• ISSN: 1749-799X

To assess whether there is a difference between measurements of odontoid incidence (OI) and other cervical sagittal parameters by X-ray radiography and those by supine magnetic resonance imaging (MRI). Standing X-ray and supine MRI images of 42 healthy subjects were retrospectively analyzed. Surgimap software was employed to measure cervical sagittal parameters including OI, odontoid tilt (OT), C2 slope (C2S), C0-2 angle, C2-7 angle, T1 slope (T1S) and T1S-cervical lordosis (CL). Paired samples t-test was applied to determine the difference between parameters measured by standing X-ray and those by supine MRI. In addition, the statistical correlation between the parameters were compared. The prediction of CL was performed and validated using the formula CL = 0.36 × OI - 0.67 × OT - 0.69 × T1S. Significant correlations and differences were found between cervical sagittal parameters determined by X-ray and those by MRI. OI was verified to be a constant anatomic parameter and the formula CL = 0.36 × OI - 0.67 × OT - 0.69 × T1S can be used to predict CL in cervical sagittal parameters. OI is verified as a constant anatomic parameter, demonstrating the necessity of a combined assessment of cervical sagittal balance by using standing X-ray and supine MRI. The formula CL = 0.36 × OI - 0.67 × OT - 0.69 × T1S can be applied to predict CL in cervical sagittal parameters.