Prognostic Significance of C1-C2 Facet Malalignment After Surgical Decompression in Adult Chiari Malformation Type I: A Retrospective Observational Study Based on The Chicago Chiari Outcome Scale. (16th November 2020)

• Record Type: Journal Article
• Authors: Vivas-Buitrago, Tito G.M; Loe, Michael L; Domingo, Ricardo; Tripathi, Shashwat; Bendok, Bernard R; Bydon, Mohamad; Quinones-Hinojosa, Alfredo; Abode-Iyamah, Kingsley O
• Is Part Of: Neurosurgery. Volume 67(2010)Supplement 1
• Publication Date: 2020-11-16
• Subjects: Nervous system -- Surgery -- Periodicals; 617.48005
• DOI: 10.1093/neuros/nyaa447_751
• Languages: English
• ISSNs: 0148-396X

Abstract

Abstract: INTRODUCTION: FMD with or without duraplasty is the most common procedure for the management of symptomatic CMI with the goal of restoring normal CSF flow.11 Despite vast surgical experience, outcomes after surgical intervention remain highly variable. METHODS: A total of 273 symptomatic patients with CMI who were treated with foramen magnum decompression (FMD), C-1 laminectomy, and duraplasty at Mayo Clinic were screened. Preoperative NSS score and postoperative NSS scores were compared using the Friedman test. Bivariate analysis was conducted to identify the preoperative variables that correlated with the outcome measures (CCOS). Multiple linear regression analysis was subsequently performed using the variables with P < .05 on the bivariate analysis to check for independent associations with the outcome measures. Statistical software SPSS version 25.0 was used for the data analysis. Significance was defined as P < .05 for all analyses. RESULTS: Fifty-two adult patients with preoperative clinical and radiological data and a minimum follow-up of 12 months were included. Motor deficits, syrinx, and C1-C2 facet malalignment were found to have a significant negative association with CCOS at 1–3 months follow-up ( P < .05), while at 9–12 month follow-up only swallowing function and C1-C2 facet malalignment were significant ( P < .05). Multivariate analysis showed that syrinx, and C1-C2 facet malalignment are independently associated with CCOS at 1–3 month follow-up. Swallowing function and C1-C2 facet malalignment were found to be independently associated with CCOS at 9–12 month follow-up. CONCLUSION: The observed results in this study suggest a significant negative correlation between C1-C2 facet malalignment and clinical outcomes evaluated by the Chicago Chiari Outcome Score at 1–3 month and 9–12 month postoperatively. Prospective studies are needed to further validate the prognostic value of C1-C2 facet malalignment and the potential role of atlantoaxial fixation as part of the treatment.