Characteristics of the DXA Measurements in Patients Undergoing Lumbar Fusion for Lumbar Degenerative Diseases: A Retrospective Analysis of Over 1000 Patients

Figures & data

Table 1 General Information and Bone Density

	Total	Male	Female
n	1041	447	594
Age (years)	62.6±7.04	62.9±7.39	62.3±6.77
BMI (kg/m^2)	26.0±3.45	25.6±2.98	26.3±3.74
L1 BMD (g/cm^2)	0.858±0.162	0.927±0.154	0.806±0.148
L2 BMD (g/cm^2)	0.918±0.182	0.995±0.172	0.860±0.168
L3 BMD (g/cm^2)	0.995±0.200	1.065±0.192	0.943±0.189
L4 BMD (g/cm^2)	1.049±0.222	1.121±0.224	0.995±0.206
Femoral neck BMD (g/cm^2)	0.676±0.121	0.726±0.115	0.639±0.112
Total hip BMD (g/cm^2)	0.830±0.135	0.890±0.122	0.784±0.126
L1 T-score	−1.53±1.38	−1.33±1.40	−1.68±1.35
L2 T-score	−1.25±1.58	−0.89±1.57	−1.53±1.53
L3 T-score	−0.87±1.79	−0.34±1.75	−1.28±1.72
L4 T-score	−0.22±2.01	0.28±2.03	−0.59±1.90
Femoral neck T-score	−1.72±0.97	−1.50±0.86	−1.89±1.01
Total hip T-score	−1.14±0.96	−0.94±0.81	−1.29±1.03

Abbreviations: BMI, body mass index; BMD, bone mineral density.

Table 2 The Prevalence of Osteoporosis or Osteopenia in Different Age Groups

Age (Years)		Total	50–59	60–69	≥70 (70–84)	P ^a
Male	Osteoporosis (%)	31.8 (142/447)	26.0 (40/154)	34.1 (71/208)	36.5 (31/85)	0.150
	Osteopenia (%)	51.9 (232/447)	61.0 (94/154)	45.7 (95/208)	50.6 (43/85)	0.015
Female	Osteoporosis (%)	50.2 (298/594)	29.5 (62/210)	58.1 (169/291)	72.0 (67/93)	< 0.001
	Osteopenia (%)	39.1 (232/594)	51.0 (107/210)	34.4 (100/291)	26.9 (25/93)	< 0.001

Notes: ^aThe chi-squared test was used to compare the prevalence between the three age groups. P < 0.05 was considered statistically significant.

Table 3 BMI- and Gender-Related Distribution of Osteoporosis Diagnosed on DXA

BMI (kg/m^2)		< 24.0	24.0–27.9	≥28.0	P ^a
Male	n	130	232	85
	Osteoporosis (%)	43.1 (56/130)	31.0 (72/232)	16.5 (14/85)	< 0.001
Female	n	159	259	176
	Osteoporosis (%)	60.4 (96/159)	50.2 (130/259)	40.9 (72/176)	0.002
Total	n	289	491	261
	Osteoporosis (%)	52.6 (152/289)	41.1 (202/491)	33.0 (86/261)	< 0.001

Notes: ^aThe chi-squared test was used to compare the prevalence between the three BMI groups. P < 0.05 was considered statistically significant.

Abbreviation: BMI, body mass index.

Table 4 Diagnosis According to Lumbar DXA and Hip DXA

Lumbar DXA	Hip DXA
	Osteoporosis	Osteopenia	Normal
Osteoporosis	153	194	8
Osteopenia	75	237	68
Normal	10	159	137

Abbreviation: DXA, dual-energy X-ray absorptiometry.

Figure 1 The anteroposterior and lateral X-ray images of a 68-year-old woman diagnosed with lumbar spinal stenosis. The T-scores of L1-L4 in the 68-year-old woman were −0.8, 0.4, 1.9 and 3.4, respectively. She had 3 abnormal segments with unreliable T-scores whose absolute value of T-score differences were all more than 1.0. From the anteroposterior and lateral X-ray images of the patient, we could observe obvious degenerative changes such as vertebral osteophytes and abdominal aortic calcifications, especially at lower segments.