Posterior Reduction of Fixed XXXX and Basilar Invagination by Atlantoaxial Facet Joint Release and Fixation: A Modified Technique With 174 Cases.

@entity1 @entity3473 @entity9807 @entity3029
BACKGROUND: Treatment of fixed @entity3029 ( @entity3029 ) with @entity3473 ( @entity3473 ) is challenging. OBJECTIVE: To introduce a modified technique to reduce fixed @entity3029 and @entity3473 through a posterior approach. METHODS: From 2007 to 2013, 174 @entity1 with fixed @entity3029 and @entity3473 underwent surgical reduction by posterior atlantoaxial facet joint release and fixation technique. RESULTS: There was 1 death in the series, and 3 @entity1 were lost to follow-up. The follow-up period ranged from 12 to 52 months (mean: 35.2 months) for the remaining 170 @entity1 . Neurological improvement was observed in 168 of 170 @entity1 (98.8%), and was stable in 1 (0.06%) and exacerbated in 1 (0.06%), with the Japanese Orthopedic Association scores increasing from 11.4 preoperatively to 15.8 postoperatively (P < .01). Radiologically, complete or >90% reduction was attained in 107 @entity1 (62.9%), 60% to 90% reduction was attained in 51 @entity1 (30%), and <50% reduction was attained in 12 @entity1 (7.1%), who underwent additional transoral decompression. Complete decompression was demonstrated in all 170 @entity1 . Solid bony fusion was demonstrated in 167 @entity1 at follow-up (98.2%). CONCLUSION: This series showed the safety and efficacy of the posterior C1-2 facet joint release and reduction technique for the treatment of @entity3029 and @entity3473 . Most fixed @entity3029 and @entity3473 cases are reducible via this method. In most cases, this method avoids transoral odontoidectomy and cervical traction. Compared with the occiput-C2 screw method, this short-segment C1-2 technique exerts less antireduction shearing force, guarantees longer bone purchase, and provides more immediate stabilization. ABBREVIATIONS: @entity3029 , @entity9807 , anterior atlantodens intervalBI, basilar invaginationC1LM, C1 lateral massCVJ, craniovertebral junctionJOA, Japanese Orthopedic AssociationVA, vertebral artery.
