Table 1 Patient demographics

N

190

110

80

Age [years]

64.7 [56.7;71.4]

65.6 [58.3;71.7]

63.1 [54.5;69.9]

BMI [kg/m²]

28.3 [25.7;32.7]

27.8 [24.8;32.2]

29.0 [26.9;33.8]

Race N (%)

 Caucasian

171 (90)

101 (91.8)

70 (87.5)

 African American

12 (6.3)

6 (5.5)

6 (7.5)

 Asian

4 (2.1)

1 (0.9)

3 (3.8)

 other

3 (1.6)

2 (1.8)

1 (1.2)

Diagnosis* N (%)

 Spinal Stenosis

150 (78.9)

86 (78.2)

64 (80)

 Foraminal Stenosis

6 (3.2)

2 (1.8)

4 (5)

 DDD

123 (64.7)

62 (56.4)

61 (76.3)

 Spondylolisthesis

154 (81.1)

87 (79.1)

67 (83.8)

 Neurogenic Claudication

57 (30)

33 (30)

24 (30)

 Herniated Nucleus Pulposus

21 (11.1)

13 (11.1)

8 (10)

Treated Segments N (%)

 I

113 (59.4)

66 (60)

47 (58.8)

 II

63 (33.2)

37 (33.6)

26 (32.5)

 III

11 (5.8)

6 (5.5)

5 (6.3)

 IV

2 (1.1)

1 (0.9)

1 (1.2)

 V

1 (0.5)

0 (0)

1 (1.2)

ASA-Score N (%)

 I

8 (4.2)

5 (4.6)

3 (3.8)

 II

136 (71.6)

79 (71.8)

57 (71.2)

 III

46 (24.2)

26 (23.6)

20 (25.0)

Comorbidities N (%)

 Diabetes Mellitus N (%)

17 (8.9)

11 (10.0)

6 (7.5)

 COPD N (%)

7 (3.7)

5 (4.6)

2 (2.5)

 Hypertension N (%)

77 (40.5)

43 (39.1)

34 (42.5)

 Congestive Heart Failure N (%)

0 (0)

0 (0)

0 (0)

 Ever Smoker N (%)

78 (41.1)

40 (36.4)

38 (47.5)