Table 1: Demographic variables of patients with simulated fixed cervical spine Note: Data in age and body mass index are presented as mean ± SD (range). Data in sex are presented as number. Data in American Society of Anesthesiologists physical status are presented as number (percentage). The above data were analyzed by Mann-Whitney U test, Chi-square test and FischerÔ's exact test. ILMA: Intubating laryngeal mask airway.