The Evaluation of Bony Union after Posterior Occipitocervical Fusion.
10.4184/jkss.2006.13.1.48
- Author:
Han CHANG
1
;
Jong Woo CHAE
;
Jong Bum PARK
;
Tae Yong BAE
;
Myung Sang MOON
Author Information
1. Spine Center, Department of Orthopaedic Surgery, Sun General Hospital, Daejeon, Korea. hc5771@chollian.net
- Publication Type:Original Article
- Keywords:
Posterior occipitocervical fusion;
Evaluation of fusion;
Stabilization
- MeSH:
Bone Transplantation;
Cervical Vertebrae;
Female;
Humans;
Immobilization;
Retrospective Studies;
Transplants
- From:Journal of Korean Society of Spine Surgery
2006;13(1):48-53
- CountryRepublic of Korea
- Language:Korean
-
Abstract:
STUDY DESIGN: The results of posterior occipitocervical fusions were analyzed retrospectively based on the results of post-operative radiographs. OBJECTIVES: To investigate subjective methods for the evaluation of occipitocervical stabilization by posterior fusion. SUMMARY OF LITERATURE REVIEW: Few studies have been performed that describe the methods utilized for the evaluation of the union of the instrumented segments. MATERIALS AND METHODS: Occipitocervical fusions were performed in 16 patients from 1995 to 2004. The patients underwent occipitocervical fusions with autogenous iliac bone grafting and wire fixation (5), loop and sublaminar wire fixation (3), C-D occipitocervical rod (2), and contoured reconstruction plate (6). The stability and failure of the instrumentation in the fusion sites were evaluated with flexion/extension lateral radiographs. The stability was evaluated by a change in the degrees and distances between the occiput and cervical vertebrae. RESULTS: Two of five patients who had undergone wire fixation with autogenous bone grafting were considered to have a nonunion because of persistent segmental instability: greater than 2 degrees and 2 mm three months postoperatively. In the other patients, we were unable to determine the presence of a solid fusion mass at the fusion site, because of overlapping of the instrumentation devices and graft bones. However, since there was no definite motion that indicated segmental instability and instrumentation breakage or loosening on flexion and extension radiographs, we considered these as stable fixations. CONCLUSION: It was difficult to evaluate whether or not the grafts were incorporated into the recipient sites, due to the complexity of the occipitocervical junction and the overlapping of the instrumentation. After removal of the external immobilization 3 months postoperatively, although flexion/extension radiographs taken 6 months postoperatively, demonstrated no motion at the fusion site, the occipitocervical fusions were judged to be stabilized rather than fused.
