Abstract
Aims: The optimal treatment of Type II odontoid fractures remains controversial. Our retrospective multicentric study of 114 odontoid process fractures documents experience with management of these fractures and discuss a new classification subtype II T and its surgical treatment. Methods: Fractures were defined using plain radiographs and CT reconstructions as per the Anderson- D’Alonzo classification. We have surgically treated 114 consecutive patients suffering from C2 odontoid fracture. 104 fractures were classified as Type II and 10 as Type III. Two cases of atypical, horizontal, mid-shaft odontoid process fractures were reported. In 55% an anterior two-screw fixation technique was chosen, remaining 45% underwent single-screw fixation. Results: One year follow-up data were available in 86.8% of cases and no major complications were found. Fusion rate calculated 6 months following surgery was 93%. We encountered cases, where the fracture line passes transversally through the middle of the shaft of odontoid process, below the level of transverse atlantal ligament, and we suggest to classify these cases as Type II T fractures. Also we analysed series of 75 surgically treated C1-2 instabilities and out of 11 pseudoarthrosis of the odontoid process 7 unrecognised Type II T fractures were found. Conclusions: Reported atypical fractures, newly classified as Type II T, are highly unstable (especially in rotations). In the authors’ opinion, two- screw technique should be the treatment of choice when internal fixation indicated.
Theses abstracts were prepared by Professor Dr. Frantz Langlais. Correspondence should be addressed to him at EFORT Central Office, Freihofstrasse 22, CH-8700 Küsnacht, Switzerland.
