Table 1.

Demographic information of the study subjects

Item	OPLL group (n=52)	Non-OPLL group (n=16)
Sex (Male n, %)	21, 40.4%	6, 37.5%
Age (Mean, min-max), years	48.6, 33.0-74.0	51.8, 46.0-64.0
Type (n, %)	Local, 20, 38.5%	Cervical fracture, 11, 68.7%
	Mixed, 5, 9.6%	CDH, 5, 31.3%
	Segmental, 27, 51.9%

OPLL, ossification of the posterior longitudinal ligament; CDH, cervical disc herniation.