Increased Cervical Spinal Instability is Associated With the Development of Proximal-type Cervical Spondylotic Amyotrophy. Issue 13 (17th July 2022)

• Record Type: Journal Article
• Authors: Ishiwata, Sho; Lizuka, Yoichi; Takasawa, Eiji; Mieda, Tokue; Kakuta, Yohei; Tomomatsu, Yusuke; Honda, Akira; Ito, Shunsuke; Inomata, Kazuhiro; Chikuda, Hirotaka
• Is Part Of: Spine. Volume 47:Issue 13(2022)
• Page Start: 938
• Page End: 943
• Publication Date: 2022-07-17
• Subjects: C3/4 flexion angle -- cervical spinal instability -- etiology -- proximal-type cervical spondylotic amyotrophy; 3; Spine -- Abnormalities -- Periodicals; Spine -- Diseases -- Periodicals; Spine -- Surgery -- Periodicals; 616.73005
• DOI: 10.1097/BRS.0000000000004314
• Languages: English
• ISSNs: 0362-2436

Abstract

Abstract : Study Design: Retrospective cohort study. Objectives: We aimed to clarify the clinical relationship between the etiology of proximal-type cervical spondylotic amyotrophy (CSA) and cervical sagittal alignment and instability. Summary of Background Data: Although several researchers have discussed hypotheses regarding the etiology of CSA, the trigger and mechanism underlying the onset remain unclear. Methods: We retrospectively analyzed 52 proximal-type CSA patients (CSA group) and 60 control patients (Control group). The following data were collected: age; sex; cervical lordosis (CL); T1 slope (TS); TS-CL; C2-7 sagittal vertical axis (SVA) on x-ray in the neutral position; flexion angle; extension angle and range of motion (ROM) of C3/4, C4/5 and C5/6; and C3/4, C4/5 and C5/6 instability (translation of >3 mm for adjacent segmental segments) on dynamic x-ray. Results: Compared with the Control group, the CSA group was associated with an older age (mean age, 67.6 vs. 61.1 years' old, P= 0.029) and male sex (78.8% vs. 50.0%, P= 0.002). In the CSA group, the radiographic parameters showed smaller C4/5 and C5/6 extension angles and C5/6 ROM values and a greater C3/4 flexion angle than the Control group. Furthermore, compared with the Control group, the CSA group was associated with C3/4 instability (13.5% vs. 3.3%, P= 0.049) and C4/5 (21.2% vs. 3.3%, P = 0.003). A logistic regression analysis, with adjusting for the age and sex, showed that the C3/4 flexion angle (odds ratio [OR], 1.2; 95% confidence interval [CI], 1.08– 1.40, P =0.002), C3/4 instability (OR, 7.3; 95% CI 1.25–42.96, P =0.027) and C4/5 instability (OR, 8.1; 95% CI, 1.56–42.19, P = 0.012) were independent risk factors of CSA. Conclusion: This study suggested that a wide C3/4 flexion angle and high C3/4 or C4/5 spinal instability were closely associated with the etiology of proximal-type CSA.