title: Factors affecting survival of patients in the acute phase of upper cervical spine injuries.
abstract: BACKGROUND
  In recent years, on the one hand, the mortality rates of upper cervical spine injuries, such as odontoid fractures, were suggested to be not so high, but on the other hand reported to be significantly high. Furthermore, it has not been well documented the relationship between survival rates and various clinical features in those patients during the acute phase of injury because of few reports. This study aimed to evaluate survival rates and acute-phase clinical features of upper cervical spine injuries.
  
  
  METHODS
  We conducted a retrospective review of all patients who were transported to the advanced emergency medical center and underwent computed tomography of the cervical spine at our hospital between January 2006 and December 2015. We excluded the patients who were discovered in a state of cardiopulmonary arrest (CPA) and could not be resuscitated after transportation. Of the 215 consecutive patients with cervical spine injuries, we examined 40 patients (18.6%) diagnosed with upper cervical spine injury (males, 28; females, 12; median age, 58.5 years). Age, sex, mechanism of injury, degree of paralysis, the level of cervical injury, injury severity score (ISS), and incidence of CPA at discovery were evaluated and compared among patients classified into the survival and mortality groups.
  
  
  RESULTS
  The survival rate was 77.5% (31/40 patients). In addition, complete paralysis was observed in 32.5% of patients. The median of ISS was 34.0 points, and 14 patients (35.0%) presented with CPA at discovery. Age, the proportion of patients with complete paralysis, a high ISS, and incidence of CPA at discovery were significantly higher in the mortality group (p = 0.038, p = 0.038, p < 0.001, and p < 0.001, respectively).
  
  
  CONCLUSIONS
  Elderly people were more likely to experience upper cervical spine injuries, and their mortality rate was significantly higher than that in injured younger people. In addition, complete paralysis, high ISS, a state of CPA at discovery, was significantly higher in the mortality group.
authors.affiliation: Department of Orthopedic Surgery, Sapporo Medical University School of Medicine, South-1, West-17, Chuo-ku, Sapporo, Hokkaido, 060-8556, Japan. morita.tomonori@sapmed.ac.jp.
authors.forename: Tomonori
authors.initials: T
authors.lastname: Morita
authors.affiliation: Department of Orthopedic Surgery, Sapporo Medical University School of Medicine, South-1, West-17, Chuo-ku, Sapporo, Hokkaido, 060-8556, Japan.
authors.forename: Tsuneo
authors.initials: T
authors.lastname: Takebayashi
authors.affiliation: Department of Emergency Medicine, Sapporo Medical University School of Medicine, Sapporo, Hokkaido, Japan.
authors.forename: Hideto
authors.initials: H
authors.lastname: Irifune
authors.affiliation: Department of Public Health, Sapporo Medical University School of Medicine, Sapporo, Hokkaido, Japan.
authors.forename: Hirofumi
authors.initials: H
authors.lastname: Ohnishi
authors.affiliation: Department of Emergency Medicine, Sapporo Medical University School of Medicine, Sapporo, Hokkaido, Japan.
authors.forename: Suguru
authors.initials: S
authors.lastname: Hirayama
authors.affiliation: Department of Orthopedic Surgery, Sapporo Medical University School of Medicine, South-1, West-17, Chuo-ku, Sapporo, Hokkaido, 060-8556, Japan.
authors.forename: Toshihiko
authors.initials: T
authors.lastname: Yamashita
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D002574:Cervical Vertebrae / Q000000981:diagnostic imaging / Q000293:injuries*; D002648:Child; D002675:Child, Preschool; D005260:Female; D006323:Heart Arrest / Q000453:epidemiology; D006761:Hospitals; D006801:Humans; D015994:Incidence; D015601:Injury Severity Score; D008297:Male; D008875:Middle Aged; D019838:Neck Injuries / Q000000981:diagnostic imaging / Q000401:mortality*; D010243:Paralysis / Q000209:etiology / Q000401:mortality*; D012189:Retrospective Studies; D013119:Spinal Cord Injuries / Q000150:complications / Q000000981:diagnostic imaging / Q000401:mortality*; D016103:Spinal Fractures / Q000000981:diagnostic imaging / Q000401:mortality*; D013124:Spinal Injuries / Q000000981:diagnostic imaging / Q000401:mortality; D015996:Survival Rate; D014057:Tomography, X-Ray Computed; D055815:Young Adult
keywords: Acute phase; Mortality rate; Spinal cord injury; Survival rate; Upper cervical spine injury