[Management of Odontoid Fractures with Compression Screw and Anterior Transarticular Screw Fixation in Elderly Patients].

PURPOSE OF THE STUDY In the management of dens axis fractures in patients older than 65 years of age the posterior approach is preferred due to osteoporosis and the risk of a failure of anterior osteosynthesis. The posterior approach, however, is associated with a higher incidence of complications. A combination of anterior transarticular fixation of C1/2 (ATS) with compression osteosynthesis of dens axis significantly increases the stability of osteosynthesis. MATERIAL AND METHODS In the period from 2009 to 2015 our hospital admitted 13 patients older than 65 years of age with a diagnosed type III dens axis fracture based on AO classification. 8 patients sustained a dens axis fracture combined with a stable atlas fracture. The cohort consisted of 13 women aged 67 to 90 years, with the mean age of 82.3 years. None of the female patients were affected neurologically. The dens axis fracture was treated by anterior approach. Once the screw was inserted in the dens axis, two more screws were added, the entrance points of those screws were medial and lateral to the odontoid screw and direction was divergently via C1/2 joints in order to reinforce stability. The patients were monitored at 6-week, 3-, 6- and 12-month follow-ups. Bone healing was confirmed by CT scan. RESULTS No complications were recorded during the surgery in any of the 13 patients. In one female patient the stabilization failed in the early postoperative period. A reoperation from anterior approach with the use of the same method was necessary. In eleven patients bone healing occurred after 6 to 12 months. In two patients pseudoarthrosis was formed with no clinical symptoms. No neurological deterioration or a patient s death was reported in the monitored period within 12 months after the treatment. DISCUSSION Where dens axis fractures in elderly patients are managed operatively, the posterior approach and transarticular fixation of C1/2 with sublaminar loop are preferred. This procedure is considered more reliable, owing to the fears of a failure of osteosynthesis by anterior approach. The most frequent cause of a failure is the pulling out of the screw through the anterior wall of dens axis base in patients with osteoporosis. Concurrently, the anterior approach is regarded as more considerate. The ATS fixation increases stability compared to isolated compression osteosynthesis, which makes it possible to manage the dens axis fractures by a more considerate anterior approach. CONCLUSIONS The ATS is a method that increases stability of compression osteosynthesis in managing dens axis in elderly patients. Key words: dens axis, upper cervical spine fracture, elderly, triple screw technique, anterior transarticular C1/2 stabilization.