Atul Goel1, Sandeep Gore2, Abhidha Shah2, Pralhad Dharurkar2, Ravikiran Vutha2, Abhinandan Patil2. 1. Department of Neurosurgery, K.E.M. Hospital and Seth G.S. Medical College, Parel, Mumbai; Lilavati Hospital and Research Centre, Bandra, Mumbai. Electronic address: atulgoel62@hotmail.com. 2. Department of Neurosurgery, K.E.M. Hospital and Seth G.S. Medical College, Parel, Mumbai.
Abstract
OBJECTIVE: The role of atlantoaxial instability in the pathogenesis of Chiari 1 formation (Chiari formation) in pediatric age-group patients is evaluated. MATERIAL AND METHODS: During the period of January 2010 to June 2017, 33 pediatric patients having Chiari formation were treated with atlantoaxial fixation. Twenty-four patients had basilar invagination, and 9 patients had no bone abnormality at the craniovertebral junction. Sixteen patients had syringomyelia, and 9 patients had both basilar invagination and syringomyelia. Considering the type of facet alignment and atlantoaxial instability, the patients were divided into 3 groups. Type 1 dislocation (13 patients) was anterior atlantoaxial instability wherein the facet of the atlas was dislocated anterior to the facet of the axis. Type 2 dislocation (5 patients) was posterior atlantoaxial instability wherein the facet of the atlas was dislocated posterior to the facet of the axis. Type 3 dislocation (15 patients) was the absence of demonstrable facet malalignment. Type 2 and 3 atlantoaxial facet instability were labeled as central atlantoaxial dislocation. In 14 patients, dynamic images showed mobile and at least partially reducible vertical atlantoaxial dislocation. RESULTS: All patients were treated with atlantoaxial plate and screw fixation using techniques described in 1994 and 2004. Foramen magnum decompression or syrinx manipulation was not performed in any patient. Occipital bone and subaxial spinal elements were not included in the fixation construct. All patients had gratifying and sustained clinical improvement. CONCLUSIONS: The outcome further confirms the cause-effect relationship of Chiari formation and atlantoaxial instability.
OBJECTIVE: The role of atlantoaxial instability in the pathogenesis of Chiari 1 formation (Chiari formation) in pediatric age-group patients is evaluated. MATERIAL AND METHODS: During the period of January 2010 to June 2017, 33 pediatric patients having Chiari formation were treated with atlantoaxial fixation. Twenty-four patients had basilar invagination, and 9 patients had no bone abnormality at the craniovertebral junction. Sixteen patients had syringomyelia, and 9 patients had both basilar invagination and syringomyelia. Considering the type of facet alignment and atlantoaxial instability, the patients were divided into 3 groups. Type 1 dislocation (13 patients) was anterior atlantoaxial instability wherein the facet of the atlas was dislocated anterior to the facet of the axis. Type 2 dislocation (5 patients) was posterior atlantoaxial instability wherein the facet of the atlas was dislocated posterior to the facet of the axis. Type 3 dislocation (15 patients) was the absence of demonstrable facet malalignment. Type 2 and 3 atlantoaxial facet instability were labeled as central atlantoaxial dislocation. In 14 patients, dynamic images showed mobile and at least partially reducible vertical atlantoaxial dislocation. RESULTS: All patients were treated with atlantoaxial plate and screw fixation using techniques described in 1994 and 2004. Foramen magnum decompression or syrinx manipulation was not performed in any patient. Occipital bone and subaxial spinal elements were not included in the fixation construct. All patients had gratifying and sustained clinical improvement. CONCLUSIONS: The outcome further confirms the cause-effect relationship of Chiari formation and atlantoaxial instability.
Authors: Misao Nishikawa; Paolo A Bolognese; Roger W Kula; Hiromichi Ikuno; Toshihiro Takami; Kenji Ohata Journal: J Neurol Surg B Skull Base Date: 2019-09-30
Authors: Arthur Wagner; Lukas Grassner; Nikolaus Kögl; Sebastian Hartmann; Claudius Thomé; Maria Wostrack; Bernhard Meyer Journal: Acta Neurochir (Wien) Date: 2020-06-06 Impact factor: 2.216