J Korean Soc Spine Surg.  2006 Mar;13(1):10-15. 10.4184/jkss.2006.13.1.10.

The Effect of Pedicle Screw Instrumentation on Fractured Vertebrae in Unstable Thoracolumbar Burst Fractures with Canal Encroachment and Clinical Result

• Lee JH
• Jun DS
• Shin WJ
• Ahn SJ

• KMID: 2040775
• DOI: http://doi.org/10.4184/jkss.2006.13.1.10

Abstract

STUDY DESIGN: A retrospective study.
OBJECTIVES
To evaluate the canal encroachment of fractured bony fragments and neurological deficits of pedicle screw instrumentation for the treatment of unstable thoracolumbar burst fractures with pedicle screws inserted into the fractured vertebrae.
MATERIALS AND METHODS
The authors evaluated 18 patients treated surgically with posterior fusions using pedicle screws for unstable thoracolumbar burst fractures, from March 2000 to September 2004. The ratios of the areas occupied by the fractured bony fragments in the canals were analyzed, before and after pedicle screw insertion, by computed tomography scans of the fractured vertebrae. The kyphotic angles, anterior vertebral heights, and neurological deficits were evaluated.
RESULTS
The areas occupied by the fractured fragments in the canals were improved significantly after surgery and there were no neurological complications resulting from the placement of pedicle screws or fragment displacements. The kyphotic angles and anterior vertebral heights at the last follow-up visits were improved significantly compared with the preoperative radiographs. The neurological deficits were not aggravated after pedicle screw insertion.
CONCLUSION
Our results suggest that pedicle screw instrumentation in fractured vertebrae is safe and effective for the treatment of unstable thoracolumbar burst fractures.

Keyword

Pedicle screw instrumentation; Fractured vertebrae; Unstable thoracolumbar burst fractures; Canal encroachment

MeSH Terms

Follow-Up Studies
Humans
Retrospective Studies
Spine*

Figure

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  Fig. 1. CT scan images of fractured vertebra. The area occupied by the fractured fragment in the canal was analyzed before and after pedicle screw insertion by the computed tomography scan in the fractured vertebra. (A) preoperative (B) postoperative

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  Fig. 2. (A) Radiograph of measurement methods for anterior vertebral height(AVH) and kyphotic angle(α). AVH = c/(a+b)/2 (B) Postoperative radiograph shows improved anterior vertebral height and kyphotic angle compared with preoperative radiograph.

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