Table 2.

Comparison of CT Attenuation in the Lumbar Spine for Patients Aged <65 Years versus Patients Aged ≥65 Years.

Lumbar Spine	<65 Years	≥65 Years	P Value
n	27	23
Mean HU	192.26	114.31	2.6 × 10−6
SD of mean HU	54.62	46.87
HU ≤ 110	2	10	.006
HU > 110	25	13
HU ≤ 135	4	16	.0001
HU > 135	23	7
HU ≤ 160	9	20	.00016
HU > 160	18	3

Abbreviations: CT, computed tomography; SD, standard deviation.