Retrospective clinical data analysis.
This study was conducted to investigate the incidence, related factors, and radiography findings of ossification of the nuchal ligament (ONL) in patient with cervical spondylosis, which could serve as a basis for further studies of the relationships between ONL and cervical spondylosis.
Injury to nuchal ligament, which might cause ONL, may aggravate cervical spine instability, leading to cervical spondylosis. Thus, it is important to understand the characteristics of ONL in patients who are diagnosed with cervical spondylosis.
Medical records of 372 patients with cervical spondylosis were reviewed. Data analysis included patients' sex, age, location and classification of ONL, and ossification of the posterior longitudinal ligament (OPLL). Radiological features were evaluated by lateral plain radiography and computed tomography for 2-dimensional sagittal plane reconstruction.
Of the 372 patients with cervical spondylosis, 49.7% had a diagnosis of ONL; the incidence of ONL was higher in males than in females (P = 0.001) and in elderly patients than in young patients (P = 0.005). The varying pictures of ONL on the plain radiography were classified into 5 types: local, continuous, segmental, mixed, and unclassified, and the distribution was 49.7%, 33.0%, 3.2%, 8.6%, and 5.4%, respectively. ONL occurred mostly at the level of C4,5 (75.7%) and C5,6 (81.1%). The incidence of ONL was higher in patients with OPLL than others (P < 0.001), and the incidence of multilevel ONL was higher in patients with OPLL than in patients with ONL only (P = 0.038).
The incidence of ONL is 49.7% in patients with cervical spondylosis. Sex, age, and OPLL are related factors of ONL. ONL can be classified into different types through morphology. Local type is the most common type of ONL, and multilevel ONL occurs mostly in patients with OPLL. C4,5 and C5,6 are the levels where ONL occurs mostly.
Level of Evidence: 4
In this study, we aimed to analyze the characteristics of ossification of the nuchal ligament (ONL) in patients with cervical spondylosis. Our study indicated that sex, age, and ossification of the posterior longitudinal ligament are related factors of ONL, and ONL has its unique features of morphology and distribution in radiography.
From the Department of Orthopaedics, Huashan Hospital, Fudan University, Shanghai, China.
Address correspondence and reprint requests to Jianyuan Jiang, MD, Department of Orthopaedics, Huashan Hospital, Fudan University, Shanghai 200030, China; E-mail: email@example.com
Acknowledgment date: June 17, 2013. First revision date: August 7, 2013. Second revision date: August 31, 2013. Acceptance date: September 16, 2013.
The manuscript submitted does not contain information about medical device(s)/drug(s).
General Program of National Natural Science Foundation of China, NSFC (No. 81071438), and Health Public Welfare Industry Research Project of China (No 201002018) funds were received to support this work.
No relevant financial activities outside the submitted work.