A Comparison of the Long-Term Results of Posterior Transarticular Stand-Alone Screw Instrumentation and Magerl Technique in Patients with Traumatic Atlantoaxial Instability: Mean 5-Year Follow-Up Study with Radiological and Patient-Rated Outcomes Assessments.

OBJECTIVE

To perform a radiological analysis of the degeneration of C1-C2 joints after C1-C2 transarticular fixation (TAF) and compare the long-term results of a routine Magerl technique (RMT) to a posterior transarticular C1-C2 stand-alone screw instrumentation (SAS) application.

METHODS

A total of 40 patients (26 men and 14 women) were included in the present retrospective observational cohort study. The mean follow-up period was 61.7 months (range, 11-118). The mean patient age at the baseline examination was 48.4 years (range, 22-82). Of the 40 patients, 11 were included in the RMT group and 29 in the SAS group.

RESULTS

The structure of 80 atlantoaxial joints was analyzed, with grade 4 degenerative changes observed in 57 joints (71.3%). Of the 40 analyzed atlanto-odontoid joints, grade 4 degenerative changes were revealed in 18 joints (45%). C1-C2 bone fusion was observed in 38 patients (95%) and stable fibrous fusion in 2 patients (5%). No cases of C1-C2 nonunion were revealed. No statistically significant differences in the frequency of C1-C2 fracture consolidation or C1-C2 fusion were revealed between the RMT and SAS groups.

CONCLUSIONS

The application of cortical lag screws in TAF might result in stable atlantoaxial joint fusion formation without joint curettage. Atlanto-odontoid joint fusion was also observed after C1-C2 TAF. The application of cortical lag screws for bilateral fixation using the SAS technique resulted in C1-C2 fusion in 93.1% of cases, comparable to the results with the Magerl technique.