IntroductionFractures of the odontoid process of the axis have been the subject of many investigations, but most articles do not consider the biological impact of age. Few publications cover the subject in the elderly population, although odontoid fractures are the most common fractures of the cervical spine in this age group. There is still a lack of agreement on the best method of treatment among patients over 65 years of age. Conservative treatment carries a high risk of developing non-union [15,19] as does halovest treatment [8]. Posterior C1-C2 fusion according to Gallie has long been the method of choice. The Gallie technique, however, is not biomechanically optimal and has a failure rate of 1/5 [9]. By adding transarticular screws the mechanical situation was improved [14,16]. Recently, the anterior screw technique according to has gained increased popularity. In most reports, younger and older patients have been grouped together. Few publications have examined the results explicitly in the elderly population. Berlemann and Schwarzenbach [5] advocated the anterior screw technique in the elderly.The present study is a review of a consecutive series of odontoid fractures in patients over 65 years of age treated at our department between 1988 and 1994. The results of anterior screw fixation, posterior C1-C2 fusion, and conservative treatment are compared. Materials and methodsThe series consists of 29 consecutive patients (18 women) with a mean age of 78 (66-99) years with odontoid fractures treated at our department between 1988 and 1994. Patient demographics and results are presented in the Table 1. Twenty-four of the fractures were Abstract This study is a retrospective analysis of patients older than 65 years with odontoid fractures. The series consisted of 29 consecutive patients with odontoid fractures (18 women, mean age 78, range 66-99 years). Twenty-six patients were neurologically intact, Frankel E, whereas three had neurological symptoms: two Frankel D and one Frankel C. Eleven patients were treated with anterior screw fixation according to Böhler, seven with a posterior C1-C2 fusion. Ten patients with either minimally displaced fractures or with complicating medical conditions were treated conservatively. At follow-up, 7/7 patients with posterior fusion had healed without any problems, whereas 8/11 patients treated with anterior screw fixation, and 7/10 conservatively treated patients were either failures or had healed, but after a complicated course of events. We conclude that anterior screw fixation according to Böhler is associated with an unacceptably high rate of problems in the elderly. Probable causes may be osteoporosis with comminution at the fracture site, or stiffness of the cervical spine preventing ideal positioning of the screws. As non-operative treatment also often fails, the method of choice seems to be posterior C1-C2 fusion.

To evaluate whether a cervical spine fracture increases the death risk in elderly patients, and to define risk factors, we studied the survival of 65 patients (26 women) with a mean age of 77 (66-99) years. 8 of the patients were tetraparetic. In 35 patients, the upper cervical spine was fractured. 7 patients suffered from ankylosing spondylitis. Severe co-morbidity was present in 16. Survival status and the date of death were retrieved from the government official personal registry. The expected survival was calculated from data retrieved from the Swedish National Board of Health and Welfare. Variables having a possible relation with survival (i.e., a p-value < 0.10 when entered into a Kaplan-Meier survival analysis) were used in a Cox multiple regression survival analysis. 53 (24-105) months after injury, 25 of the 65 patients had died. The survival was significantly lower than the expected values. Severe co-morbidity (risk ratio: 5,6), neurological injury (6,4), high age (1,1), and ankylosing spondylitis (5,5) proved to be significant risk factors for death. Thus, a cervical spine fracture may lead to earlier death in a patient with a severe co-morbidity. A neurological complication constitutes a risk also for a previously healthy individual. Patients having ankylosing spondylitis (with increased death risk) run a higher than normal risk of sustaining a cervical spine fracture.