Table 1. Arthrodesis rates in lumbar fusion procedures.

First author	Study design	No. of subjects	Fusion rates	Comments
Andersen4	Retrospective case series	426 (smokers: 232; nonsmokers: 194)	Nonsmokers: 91.1%; all smokers: 84.8% (p = 0.066); >10 cigarettes/d: 81.8% (p = 0.03)	Significantly higher nonunion rate in patients who smoked >10 cigarettes/d
Brown2	Retrospective cohort study	100 (smokers: 50; nonsmokers: 50)	Nonsmokers: 92%; smokers: 60% (p = 0.001)	Higher rates of nonunion in smokers independent of age, race, or sex
Bydon5	Retrospective case series	281 (smokers: 50; nonsmokers: 231)	Single-level fusions: nonsmokers: 92.31%; smokers: 90.18% (p = 0.738) Two-level fusions: nonsmokers: 89.08%; smokers: 70.83% (p = 0.019)	Significantly higher rates of pseudarthrosis in smokers undergoing two-level procedures
Glassman6	Retrospective case series	357 (smokers: 188; nonsmokers: 169)	Nonsmokers: 85.8%; smokers: 79.3% (p = 0.05)	Significantly higher nonunion rates in all smokers; fusion success improved with postoperative smoking cessation