Facet tropism: a comparison between far lateral and posterolateral lumbar disc herniations.
METHODS
An assessment of the difference in the degree of facet tropism and disc degeneration between far lateral and posterolateral lumbar disc herniations.


OBJECTIVE
To investigate the effect of the difference in the degree of the facet tropism and disc degeneration with respect to the development of far lateral lumbar disc herniation and posterolateral lumbar disc herniation, and to compare the effect between the two types of herniations.


BACKGROUND
The effect of facet tropism on the development of posterolateral lumbar disc herniation has been investigated previously, but there has been no study on far lateral lumbar disc herniation.


METHODS
Thirty-eight lumbar disc herniations (far lateral, n = 19; posterolateral, n = 19) were included this study. The degree of facet tropism and disc degeneration was measured at the herniated disc level by using magnetic resonance imaging. The results were compared to show any differences between the two types of lumbar disc herniations.


RESULTS
There were significant differences in the degree of facet tropism (24.74 vs. 14.26, P = 0.004) and disc degeneration (23.92 vs. 15.08, P = 0.005) between the far lateral and posterolateral lumbar disc herniations. There was no significant correlation between the degree of facet tropism and the degree of disc degeneration in far lateral lumbar disc herniation (r = -0.369, P = 0.120).


CONCLUSIONS
This results suggest that the differences in the degree of facet tropism and disc degeneration might be considered a key factor in distinguishing the development of far lateral lumbar disc herniation from that of posterolateral lumbar disc herniation.
Department of Orthopaedic Surgery, The Catholic University of Korea College of Medicine, Seoul, Korea. spinepjb@@cmc.cuk.ac.kr
J B
JB
Park
H
H
Chang
K W
KW
Kim
S J
SJ
Park
D000328:Adult; D000368:Aged; D000886:Anthropometry; D015984:Causality; D005260:Female; D006801:Humans; D007403:Intervertebral Disc / Q000473:pathology* / Q000503:physiopathology; D007405:Intervertebral Disc Displacement / Q000473:pathology* / Q000503:physiopathology; D008159:Lumbar Vertebrae / Q000473:pathology* / Q000503:physiopathology; D008279:Magnetic Resonance Imaging; D008297:Male; D008875:Middle Aged; D021801:Zygapophyseal Joint / Q000473:pathology* / Q000503:physiopathology