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PubMed · 16291111

A functional classification of spinal instrumentation.

Mark R Foster
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Abstract

BACKGROUND CONTEXT: Spinal instrumentation systems have evolved far beyond the original Harrington design, with increasing complexity and capabilities. This review attempts to de-emphasize the "product names," as systems are often generically and inappropriately referred to as "Harrington rods," by introducing a functional classification for current systems. PURPOSE: The aim of this paper is to review the intended design purpose of current spinal instrumentation systems for more accurate interpretations of radiographs and complications. STUDY DESIGN: The principles involved in each type of instrumentation system are described, followed by the characteristic components and the normal appearance radiographically, with examples of complications, which should be recognized. METHODS: The historical contribution of specific systems in the developing art of internal fixation of the spine is provided as a background to understand the biomechanical forces imparted by spinal hardware. Recognizing the functional intent of spinal constructs will enhance descriptions of those images. RESULTS: Spinal instrumentation has been categorized into five functional types: Distraction and compression, segmental stabilization, coupled or derotation systems, translational or pedicle screw systems, and anterior instrumentation. CONCLUSIONS: Analysis of radiographs from a functional viewpoint can enhance the descriptive interpretation and specifically allow assessment of the success or of the presence of complications, which are crucial to the analysis of instrumentation effectiveness.

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Equipment DesignExternal FixatorsHumansInternal FixatorsOsteogenesis, DistractionSpinal FusionSpineJournal ArticleReview

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BibTeXRIS

Mark R Foster. A functional classification of spinal instrumentation.. https://doi.org/10.1016/j.spinee.2004.11.017

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