To compare the clinical efficacy and fusion rate of unilateral and bilateral C₁ and C₂ pedicle screw fixation of unstable Jefferson fractures.

This retrospective case-control study enrolled 22 patients with unstable Jefferson fractures admitted between April 2012 and May 2015. There were 18 males and four females, with the mean age of 52.9 years (range, 35-67 years). Mean preoperative visual analogue scale (VAS) was 6.09 points (range, 4-8 points). According to the American spinal injury association (ASIA) classification, two patients were rated grade D and one patient grade C. Mean Japanese orthopedic association (JOA) score was 12.3 points. Bilateral C₁ and C₂ pedicle screw fixation was performed for 15 patients (bilateral group). Advantage side unilateral C₁ and C₂ pedicle screw fixation was performed for seven patients with extremely unstable fracture or narrow pedicle (unilateral group). Operation time, blood loss and surgical complications were recorded. VAS was used to evaluate the improvement of neck pain after operation. ASIA classification and JOA score were used to assess nerve function recovery. Atlanto-dental interval (ADI), srew position and bone fusion were evaluated after operation.

All patients successfully completed the operation. Operation time was (119.5±21.2)min, and blood loss was (280.1±83.1)ml. A total of 74 screws were placed and CT scan showed satisfactory position of the screws. No complications were noted either during the operation or after surgery. All patients were followed up for mean 20.7 months (range, 13-33 months). VAS was improved in both groups after operation (P<0.01), and there was no significant difference between the two groups (P>0.05). Two patients with ASIA grade D in bilateral group were improved to ASIA grade E after operation. One patient with ASIA grade C in unilateral group was improved to ASIA grade D after operation. JOA score increased to mean 15.7 points at last follow-up. ADI were decreased in both groups after operation(P<0.05), but there was no significant difference between the two groups (P>0.05). All patients had bony fusion 6 months after operation, with similar fusion rate between the two groups (P>0.05).

Advantage side unilateral screw fixation can be used for the patients with bilateral C₁ and C₂ pedicle screw fixation failure, for the technique can improve cervical pain and provide relatively high stability and fusion rate.

Atlanto-occipital joint; Spinal fractures; Internal fixators; Spinal fusion