Radiographic Analysis of Atlantoaxial Fusion for Atlantoaxial Instability: Comparison of Posterior wiring, Transarticular screw, Posterior screw-rod fixation.
10.4184/jkss.2010.17.4.157
- Author:
Jae Yoon CHUNG
1
;
Hyoung Yeon SEO
;
Ki Hyeong KIM
;
Geon Woo LEE
Author Information
1. Department of Orthopedics, Chonnam National University Hospital, Gwangju, Korea. jychung@jnu.ac.kr
- Publication Type:Original Article
- Keywords:
Atlantoaxial instability;
Atlantoaxial fusion;
Subaxial cervical spine alignment
- MeSH:
Arthritis, Rheumatoid;
Atlanto-Axial Joint;
Congenital Abnormalities;
Follow-Up Studies;
Humans;
Kyphosis;
Ligaments;
Retrospective Studies;
Rupture;
Spine
- From:Journal of Korean Society of Spine Surgery
2010;17(4):157-163
- CountryRepublic of Korea
- Language:Korean
-
Abstract:
STUDY DESIGN: This is a retrospective study. OBJECTIVES: We wanted to clarify the association between the position of the atlantoaxial fusion angle and the change of the subaxial cervical spine alignment (SCA) and the reduction loss after atlantoaxial fusion (AAF) using the posterior wiring technique (PWT), transarticular screw fixation (TAF) and posterior screw-rod fixation (PSR) for treating atlantoaxial instability (AAI). SUMMARY OF LITERATURE REVIEW: There are not many studies on the change of the SCA and the reduction loss after AAF. MATERIALS AND METHODS: Thirty five patients underwent AAF for AAI from 1986 to 2008. The mean follow-up period was 59.5 months. The surgical techniques were divided into three groups, that is, PWT: 17 patients, TAS: 10 and PSR: 8. The causes of instability were transverse ligament rupture in 12 patients, rheumatoid arthritis in 11, Os odontoideum in 6 and nonunion of an odontoid fracture in 6. Plain radiographs were used to assess the atlanto-dental interval, the posterior arch-lamina angle, the change of the SCA and the time of fusion. RESULTS: Fusion was achieved in all the patients within 3.5 months (range: 3-5 months). The radiologic findings in the 5 PWT patients showed a reduction loss and 3 patients showed subaxial cervical kyphosis (SCK). The TAS group had no reduction loss or SCK. The PSR group had no reduction loss and one patient showed SCK. A statistically significant reduction loss and SCK occurred in the group in which there was a posterior arch-laminar angle greater than 10 degrees before and after surgery. CONCLUSIONS: For the treatment of AAI, the position of the AAF is associated with the change of the postoperative SCA. The preoperative lodortic position of C1-2 should be maintained to prevent the change of the SCA.