The changes of syrinx volume after posterior reduction and fixation of basilar invagination and atlantoaxial dislocation with syringomyelia

Zuowei Wang,Fengzeng Jian,Xingwen Wang,Zan Chen,Hao Wu,Can Zhang

doi:10.1007/s00586-016-4740-9

Zuowei Wang, Fengzeng Jian + Show 4 more

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https://doi.org/10.1007/s00586-016-4740-9

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Abstract

PurposeThe purpose of this study focuses on the changes of the syrinx volume after posterior reduction and fixation of the basilar invagination (BI) and atlantoaxial dislocation (AAD) with syringomyelia.MethodsWe retrospectively analyzed the clinical outcome and syrinx volume changes in 71 patients with BI, AAD and syringomyelia treated with the posterior reduction and fixation technique.ResultsClinical improvement was observed in 64 (90.1 %) patients postoperatively; 5 (7.0 %) were stable and 2 (2.8 %) were clinically aggravated. The postoperative Atlantodental interval became normal in 61 patients (86.0 %); showed reduction that was greater than 50 % but not complete in 5 patients (7.0 %); and reduction which was less than 50 % in 5 patients (7.0 %). The size of the syrinx was reduced postoperatively in 66 patients (93.0 %) while no change in the remaining 5 patients (7.0 %).ConclusionsPosterior reduction and fixation of the AAD and BI can effectively enlarge the foramen magnum, improve the cerebrospinal fluid circulation and consequently reduce the volume of the syrinx.

Highlights

Basilar invagination (BI) is a congenital malformation of craniovertebral junction (CVJ), which is divided into two types based on whether it is associated with atlantoaxial dislocation (AAD) [1,2,3]
Purpose The purpose of this study focuses on the changes of the syrinx volume after posterior reduction and fixation of the basilar invagination (BI) and atlantoaxial dislocation (AAD) with syringomyelia
The postoperative Atlantodental interval became normal in 61 patients (86.0 %); showed reduction that was greater than 50 % but not complete in 5 patients (7.0 %); and reduction which was less than 50 % in 5 patients (7.0 %)

Summary

Introduction

Basilar invagination (BI) is a congenital malformation of craniovertebral junction (CVJ), which is divided into two types based on whether it is associated with atlantoaxial dislocation (AAD) [1,2,3]. Syringomyelia is very common in the type of BI with AAD [3,4,5,6]. In patients affected by BI and AAD, transoral odontoidectomy could effectively decompress the foramen magnum (FM) and improve the clinical symptoms [5, 6]. The posterior reduction and fixation technique has become the preferred treatment option for BI and AAD with favorable restoration of the AAD being reported [1, 2, 4, 7, 8]. The clinical data of patients with BI/AAD and syringomyelia that underwent direct posterior reduction and fixation were retrospectively analyzed; the possible influencing factors of the syrinx volume were discussed

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