Morphologic Changes in Contralateral Lumbar Foramen in Unilateral Cantilever Transforaminal Lumbar Interbody Fusion Using Kidney-type Intervertebral Spacers. Issue 5 (June 2015)

• Record Type: Journal Article
• Authors: Iwata, Takahiro; Miyamoto, Kei; Hioki, Akira; Fushimi, Kazunari; Ohno, Takatoshi; Shimizu, Katsuji
• Is Part Of: Journal of spinal disorders & techniques. Volume 28:Issue 5(2015)
• Publication Date: 2015-06
• Subjects: Spinal cord -- Diseases -- Periodicals; Spinal cord -- Surgery -- Periodicals; Spinal Diseases -- therapy -- Periodicals; Cordotomy -- methods -- Periodicals; Spinal Cord Diseases -- therapy -- Periodicals; Spinal Fusion -- methods -- Periodicals; Spine -- surgery -- Periodicals; 616.73
• DOI: 10.1097/BSD.0b013e318286bb14
• Languages: English
• ISSNs: 1536-0652

Abstract

<abstract> <title> <x xml:space="preserve">Abstract</x> </title> <sec> <title>Study Design:</title> <p>A retrospective study of 58 patients undergoing cantilever transforaminal lumbar interbody fusion (c-TLIF).</p> </sec> <sec> <title>Objectives:</title> <p>To evaluate morphologic changes in the intervertebral foramen (IVF) on the side contralateral to spacer insertion in patients undergoing c-TLIF using plain x-ray films and computed tomography scan.</p> </sec> <sec> <title>Summary of Background Data:</title> <p>The morphologic changes in the contralateral lumbar foramen in c-TLIF using unilateral insertion of spacers have not been well studied.</p> </sec> <sec> <title>Materials and Methods:</title> <p>Fifty-eight consecutive patients with lumbar dysplastic changes or degenerative disk diseases underwent c-TLIF using 96 kidney-type spacers with local bone grafts. Radiographic findings (sagittal disk angle), computed tomography scan findings (coronal disk angle, disk height, foraminal height (FH), foraminal width, and cross-sectional area of IVF in contralateral lumbar foramen) were compared between preoperative period and 6 months after surgery. The correlations between contralateral lumbar foraminal dimensions and disk height, sagittal disk angle, and coronal disk angle were analyzed.</p> </sec> <sec> <title>Results:</title> <p>After c-TLIF, sagittal angle, disk height, FH, foraminal width, and cross-sectional area of the IVF were significantly increased. Increase in posterior disk height showed a positive correlation with increases in FH, foraminal width, and cross-sectional area of IVF (<italic>r</italic>=0.235–0.511). However, the increase in sagittal disk angle showed a negative correlation with changes in foraminal width and cross-sectional area of IVF (<italic>r</italic>=–0.256 to –0.206).</p> </sec> <sec> <title>Conclusions:</title> <p>Lumbar foraminal dimensions on the side contralateral to spacer insertion increased significantly after c-TLIF, suggesting that c-TLIF enables indirect decompression of the contralateral nerve root. Although increase in posterior disk height was shown to be an important factor to increase contralateral foraminal size, segmental lordosis was a risk factor for a decrease in contralateral foraminal size.</p> </sec> </abstract>