Analysis of risk factors associated with XXXX after anterior odontoid screw fixation.

@entity177 @entity1 @entity174
STUDY DESIGN: Retrospective study. OBJECTIVE: To evaluate the incidence of @entity177 after anterior screw fixation of type II and rostral shallow @entity174 and to identify related risk factors. SUMMARY OF BACKGROUND DATA: Although several studies have reported fusion rates after anterior odontoid screw fixation of type II and rostral shallow @entity174 , few reports have analyzed in detail the risk factors associated with @entity177 . METHODS: Forty-one @entity1 with a type II and rostral shallow type III odontoid @entity174 were treated using anterior screw fixation. The @entity1 were 33 @entity1 and 8 @entity1 mean age = 46.6 years; age range = 15-79 years. Range of follow-up was 7 to 48 months. RESULTS: Anterior odontoid screw fixation resulted in solid bony union in 33 @entity1 (80.5%), fibrous union in 3 (7.3%), and nonunion in 5 (12.2%). When surgery was delayed for more than 1 week, the incidence of @entity177 significantly increased (P = 0.0051). Furthermore, a @entity174 gap of 2 mm or more was found to be significantly associated with @entity177 (P = 0.0172). However, @entity1 age and @entity174 were not found to be significantly associated with @entity177 (P = 0.8236 and P = 0.5762, respectively). CONCLUSION: Our study of anterior odontoid screw fixation reveals that the risk of @entity177 is 37.5 times greater in @entity1 with a delay of more than 1 week before operation, and 21 times greater in @entity1 with a @entity174 gap of greater than 2 mm.
