Table 2 Tabulation of different ROI CT attenuation values, expressed in Hounsfield unit (HU) for L1 to L4 and their mean values and 95% confidence interval (CI), for DXA-defined normal, osteopenia, and osteoporosis subgroup

L1

BMD (g/cm²)

1.11 (1.02, 1.19)*

0.89 (0.84, 0.96)^▲

0.71 (0.62, 0.77)^▲,*

Round ROI_CT (HU)

164.00 (131.00, 223.00)*

131.00 (75.25, 165.75)^▲

73.00 (33.00, 91.00)^▲,*

Oval ROI_CT (HU)

172.00 (128.50, 219.00)*

128.00 (85.00, 165.00)^▲

69.00 (36.00, 93.00)^▲,*

Right ROI_CT (HU)

163.00 (117.50, 196.00)*

116.50 (89.75, 148.25)^▲

74.00 (50.00, 96.00)^▲,*

Front ROI_CT (HU)

169.00 (134.00, 219.50)*

135.00 (83.00, 168.25)^▲

71.00 (38.00, 92.00)^▲,*

Left ROI_CT (HU)

189.00 (138.00, 203.00)*

130.00 (101.00, 163.50)^▲

73.00 (47.00, 98.00)^▲,*

L2

BMD (g/cm²)

1.18 (1.07, 1.27)*

0.94 (0.90, 0.98)^▲

0.75 (0.63, 0.83)^▲,*

Round ROI_CT (HU)

163.00 (141.00, 213.00)*

106.00 (74.75, 139.25)^▲

68.00 (38.00, 99.00)^▲,*

Oval ROI_CT (HU)

156.00 (127.00, 208.00)*

110.00 (73.50, 141.25)^▲

73.00 (36.00, 106.00)^▲,*

Right ROI_CT (HU)

140.00 (109.50, 200.00)*

103.50 (91.25, 137.75)^▲

71.00 (41.00, 102.00)^▲,*

Front ROI_CT (HU)

153.00 (127.50, 213.00)*

110.50 (80.00, 146.75)^▲

69.00 (40.00, 104.00)^▲,*

Left ROI_CT (HU)

162.00 (126.00, 200.50)*

115.50 (84.25, 152.75)^▲

71.00 (31.00, 105.00)^▲,*

L3

BMD (g/cm²)

1.29 (1.15, 1.38)*

1.03 (0.95, 1.07)^▲

0.80 (0.65, 0.86)^▲,*

Round ROI_CT (HU)

153.00 (111.50, 208.00)*

95.50 (61.00, 132.00)^▲

53.00 (27.00, 75.00)^▲,*

Oval ROI_CT (HU)

152.00 (116.00, 205.00)*

94.00 (62.50, 138.50)^▲

48.00 (28.00, 75.00)^▲,*

Right ROI_CT (HU)

154.00 (110.50, 199.00)*

100.50 (75.87, 118.50)^▲

68.00 (36.00, 92.00)^▲,*

Front ROI_CT (HU)

152.00 (119.00, 210.00)*

95.00 (64.50, 135, 75)^▲

54.00 (24.00, 79.00)^▲,*

Left ROI_CT (HU)

166.00 (134.00, 205.00)*

100.50 (78.50, 127.50)^▲

58.00 (37.00, 91.00)^▲,*

L4

BMD (g/cm²)

1.29 (1.15, 1.38)*

1.02 (0.95, 1.07)^▲

0.82 (0.68, 0.88)^▲,*

Round ROI_CT (HU)

166.00 (118.00, 218.50)*

99.00 (60.50, 132.00)^▲

58.00 (16.00, 81.00)^▲,*

Oval ROI_CT (HU)

164.00 (115.50, 206.50)*

94.00 (61.25, 130.50)^▲

55.00 (23.00, 85.00)^▲,*

Right ROI_CT (HU)

179.00 (134.00, 247.00)*

134.00 (97.50, 173.25)^▲

81.00 (46.00, 103.00)^▲,*

Front ROI_CT (HU)

171.00 (121.00, 222.00)*

101.50 (69.00, 135.25)^▲

65.00 (22.00, 88.00)^▲,*

Left ROI_CT (HU)

196.00 (128.00, 226.50)*

119.00 (93.50, 152.50)^▲

83.00 (53.00, 104.00)^▲,*

L1–L4

BMD (g/cm²)

1.24 (1.10, 1.28)*

0.99 (0.92, 1.03)^▲

0.77 (0.64, 0.84)^▲,*

Round ROI_CT (HU)

162.25 (123.25, 217.25)*

107.00 (68.88, 142.00)^▲

53.00 (35.00, 85.25)^▲,*

Oval ROI_CT (HU)

158.75 (123.38, 213.13)*

102.63 (71.69, 140.81)^▲

54.75 (32.25, 88.50)^▲,*

Right ROI_CT (HU)

156.75 (120.88, 206.88)*

111.50 (93.94, 149.13)^▲

74.00 (47.25, 98.00)^▲,*

Front ROI_CT (HU)

159.00 (125.13, 214.75)*

107.25 (70.94, 144.75)^▲

57.25 (53.50, 85.75)^▲,*

Left ROI_CT (HU)

171.25 (135.75, 214.50)*

115.00 (96.63, 142.50)^▲

68.00 (41.75, 103.75)^▲,*