Nonuniform settlement of C2 lateral mass: a pathological anatomic change related to the lateral atlantoaxial osteoarthritis
- 1Department of Orthopedics, The Affiliated Hospital, Southwest Medical University, Luzhou, China
- 2Department of Orthopedics, The Second Affiliated Hospital (Xinqiao Hospital) of Army Medical University, No. 83, Xinqiao Main Street, Chongqing, China
Abstract
Objective: Nonuniform settlement of C2 lateral mass (C2LM-NUS) was defined as an asymmetrical change of the bilateral C2 lateral masses. This study aimed to determine the association between the nonuniform settlement of C2 lateral mass (C2LM-NUS) and lateral atlantoaxial osteoarthritis (AAOA).
Methods: A total of 573 patients who underwent a head and neck or cervical spine CT scan were reviewed. The morphological parameters were measured, including C2 lateral mass settlement (C2LMS), lateral atlantodental interval (LADI), coronal deviation angle of odontoid process (Od-CDA), and C1/2 relative rotation angle (C1/2 RRA). The lateral AAOA was recorded. The patients with a difference in C2LMS between the bilateral sides (d-C2LMS) of more than 1.4 mm were assigned to the C2LM-NUS group.
Results: There were 154 patients in the C2LM-NUS group and 419 in the control group. The median values of the difference in LADI between the two sides (d-LADI), Od-CDA, and C1/2 RRA in the C2LM-NUS group were greater than those in the control group (p < .001 for all). The prevalence of lateral AAOA in patients with C2LM-NUS was higher than in the control group (33.8% vs 19.1%, p < .001). Multivariate logistic regression analysis revealed that the C2LM-NUS was an independent risk factor for lateral AAOA (Adjusted Odds Ratio: 2.382, p < .001).
Conclusion: This study indicated that the C2LM-NUS, an independent anatomical risk factor for lateral AAOA, was associated with asymmetric morphological changes of the AAJ.
Supplementary Information: The online version contains supplementary material available at https://doi.org/10.1186/s12891-026-10285-2.
Related
- The Anatomic-Atraumatic-Anterior Reconstructive Technique (A-A-ART) for total hip arthroplasty: A step-by-step pictorial guide to a minimally invasive approach for hip osteoarthritis.
- Cost-effectiveness of anatomic total shoulder arthroplasty versus pyrocarbon hemiarthroplasty for glenohumeral osteoarthritis: a 10-year Markov cost-utility analysis
- Reprogramming pathological secretory phenotype of chondrocytes inhibits neurovascular invasion for osteoarthritis treatment.
- Network Pharmacology and Experimental Evidence Indicate That Dihydrochelerythrine from Toddalia asiatica Ameliorates Pathological Features of Knee Osteoarthritis in Rats and Is Associated with PI3K/AKT Signaling.
- Evaluating the role of craniocervical and atlantoaxial instability in autonomic dysfunction: a narrative review
BibTeX
@article{tang2026nonuniform,
title = {{Nonuniform settlement of C2 lateral mass: a pathological anatomic change related to the lateral atlantoaxial osteoarthritis}},
author = {Chao Tang and Ying Zhang and Xian Ming Huang and Xu Zhao and Tong Wei Chu},
journal = {BMC Musculoskeletal Disorders},
year = {2026},
month = jul,
doi = {10.1186/s12891-026-10285-2},
url = {https://doi.org/10.1186/s12891-026-10285-2},
note = {CC BY-NC-ND 4.0},
}
RIS
TY - JOUR
TI - Nonuniform settlement of C2 lateral mass: a pathological anatomic change related to the lateral atlantoaxial osteoarthritis
AU - Chao Tang
AU - Ying Zhang
AU - Xian Ming Huang
AU - Xu Zhao
AU - Tong Wei Chu
PY - 2026
DA - 2026/07/28
JO - BMC Musculoskeletal Disorders
DO - 10.1186/s12891-026-10285-2
UR - https://doi.org/10.1186/s12891-026-10285-2
AB - Objective: Nonuniform settlement of C2 lateral mass (C2LM-NUS) was defined as an asymmetrical change of the bilateral C2 lateral masses. This study aimed to determine the association between the nonuniform settlement of C2 lateral mass (C2LM-NUS) and lateral atlantoaxial osteoarthritis (AAOA). Methods: A total of 573 patients who underwent a head and neck or cervical spine CT scan were reviewed. The morphological parameters were measured, including C2 lateral mass settlement (C2LMS), lateral atlantodental interval (LADI), coronal deviation angle of odontoid process (Od-CDA), and C1/2 relative rotation angle (C1/2 RRA). The lateral AAOA was recorded. The patients with a difference in C2LMS between the bilateral sides (d-C2LMS) of more than 1.4 mm were assigned to the C2LM-NUS group. Results: There were 154 patients in the C2LM-NUS group and 419 in the control group. The median values of the difference in LADI between the two sides (d-LADI), Od-CDA, and C1/2 RRA in the C2LM-NUS group were greater than those in the control group (p < .001 for all). The prevalence of lateral AAOA in patients with C2LM-NUS was higher than in the control group (33.8% vs 19.1%, p < .001). Multivariate logistic regression analysis revealed that the C2LM-NUS was an independent risk factor for lateral AAOA (Adjusted Odds Ratio: 2.382, p < .001). Conclusion: This study indicated that the C2LM-NUS, an independent anatomical risk factor for lateral AAOA, was associated with asymmetric morphological changes of the AAJ. Supplementary Information: The online version contains supplementary material available at https://doi.org/10.1186/s12891-026-10285-2.
SN - 1471-2474
ER -