565 - Influence of Smoking on Two Level Anterior Cervical Discectomy and Fus...

Oral Posters: Cervical

Presented by: S. Niedermeier - View Audio/Video Presentation (Members Only)

Author(s):

E. Cerier(1), N. Jain(2), S. Lenobel(1), E. Yu(2), S. Niedermeier(1)

(1) Ohio State University, Columbus, OH, United States
(2) Ohio State University, Orthopaedics, Columbus, OH, United States

Abstract

Introduction: Studies have demonstrated decreased fusion rates, greater collapse and increased interspace angle loss with multi-level cervical fusions in smoking patients. There is less convincing evidence on the negative effects of smoking on fusion in a single-level ACDF, while there are no specific reports of the impact of smoking in a two-level ACDF. Adding knowledge of this impact may help in patient education about the risks of a poor outcome following surgery.

Methods: Patients ≥18 years of age (no upper limit at the time of the procedure) who had a two-level ACDF to treat cervical radiculopathy or myelopathy, performed at a single institution between January 2008 and September 2015 were enrolled. Demographic and pre-operative clinical information was recorded for all patients. Patients were classified as smokers if they currently smoked at the time of the procedure or had quit within 6 months of the procedure. Fusion status was assessed using standard cervical spine radiographs. Patient reported outcomes were captured with Neck Disability Index (NDI) questionnaires. Results were analyzed using the Chi-square test to compare fusion status between smokers and nonsmokers. NDI scores were compared by a one-way analysis of variance (ANOVA) and an unpaired t-test, as appropriate.

Results: A total of 61 patients met our inclusion criteria, out of which 23 were smokers at the time of procedure. The mean age of smokers (n=23) was 47.7 ±8.2 years and for non-smokers (n=38) was 52.10 ±8.6 years (p >0.05). The median follow-up time was 12 months. 11 smokers (61%) and 17 (53%) non-smokers demonstrated definite evidence of fusion. Five (28%) smokers and 13 (41%) non-smokers showed delayed fusion, and two (11%) smokers and two (6%) non-smokers demonstrated evidence of nonunion. The difference in fusion status between smokers and non-smokers was not statistically significant (p=0.58). Pre-operatively, smokers had an average NDI of 62.19, with a 13.6 %, 7.4 %, and 27.6 % decrease at 3, 6, and 12 months respectively. Non-smokers had a pre-operative average NDI of 45.37, with a 29 %, 53.9 % and 64.5 % decrease at 3, 6, and 12 months respectively.

Conclusion: Smoking was not associated with a decreased rate of radiographic fusion. However, smokers had lower and less progressive improvements of NDI scores compared to non-smokers. Pre-operative counseling should include education about risks of inferior clinical outcomes in smokers independent of fusion status.