. 2012 Dec 14;6(4):249–256. doi: 10.4184/asj.2012.6.4.249
Copyright © 2012 by Korean Society of Spine Surgery
This is an Open Access article distributed under the terms of the Creative Commons Attribution Non-Commercial License (http://creativecommons.org/licenses/by-nc/3.0/) which permits unrestricted non-commercial use, distribution, and reproduction in any medium, provided the original work is properly cited.
Table 4.
Risk factors
Values are presented as number (%).