Christopher E Wolfla1. 1. Department of Neurosurgery, The Medical College of Wisconsin, 9200 West Wisconsin Avenue, Milwaukee, WI 53226, USA. cwolfla@neuroscience.mcw.edu
Abstract
BACKGROUND CONTEXT: Patients with cervical myelopathy secondary to craniocervical instability commonly present with spinal cord compression secondary to a combination of static forces and gross instability. Craniocervical arthrodesis is therefore indicated in the treatment of the majority of these conditions. In order to facilitate arthrodesis, techniques for occipitocervical instrumentation have been developed. PURPOSE: To systematically review the anatomy, biomechanics, and practical considerations involved in posterior occipitocervical instrumentation. STUDY DESIGN: Retrospective literature review. PATIENT SAMPLE: Not applicable. OUTCOME MEASURES: Not applicable. METHODS: Retrospective literature review. RESULTS: The anatomic elements of the craniocervical junction include the occipital bone, occipital condyles, atlas (C1), and axis (C2). The occiput-C1 and C1-C2 motion segments possess unique mechanical properties. Occipitocervical instrumentation constructs are comprised of points of fixation and longitudinal elements, each with characteristic strengths and weaknesses. CONCLUSIONS: Analysis of the anatomy, available points of fixation, and the movements to be controlled leads to the choice of a longitudinal element which can control movement by incorporating the strongest points of fixation. By going through this process for each patient, an informed decision may be made regarding the optimal occipitocervical instrumentation construct.
BACKGROUND CONTEXT: Patients with cervical myelopathy secondary to craniocervical instability commonly present with spinal cord compression secondary to a combination of static forces and gross instability. Craniocervical arthrodesis is therefore indicated in the treatment of the majority of these conditions. In order to facilitate arthrodesis, techniques for occipitocervical instrumentation have been developed. PURPOSE: To systematically review the anatomy, biomechanics, and practical considerations involved in posterior occipitocervical instrumentation. STUDY DESIGN: Retrospective literature review. PATIENT SAMPLE: Not applicable. OUTCOME MEASURES: Not applicable. METHODS: Retrospective literature review. RESULTS: The anatomic elements of the craniocervical junction include the occipital bone, occipital condyles, atlas (C1), and axis (C2). The occiput-C1 and C1-C2 motion segments possess unique mechanical properties. Occipitocervical instrumentation constructs are comprised of points of fixation and longitudinal elements, each with characteristic strengths and weaknesses. CONCLUSIONS: Analysis of the anatomy, available points of fixation, and the movements to be controlled leads to the choice of a longitudinal element which can control movement by incorporating the strongest points of fixation. By going through this process for each patient, an informed decision may be made regarding the optimal occipitocervical instrumentation construct.
Authors: Heiko Koller; Rene Schmidt; Michael Mayer; Wolfgang Hitzl; Juliane Zenner; Stefan Midderhoff; Stefan Middendorf; Nicolaus Graf; Nicolaus Gräf; H Resch; Hans-Joachim Wilke; Hans-Joachim Willke Journal: Eur Spine J Date: 2010-06-30 Impact factor: 3.134
Authors: Fraser C Henderson; Robert Rosenbaum; Malini Narayanan; Myles Koby; Kelly Tuchman; Peter C Rowe; Clair Francomano Journal: Neurosurg Rev Date: 2020-07-04 Impact factor: 3.042