Table 1 Characteristics of study participants

Age (years), mean ± SD

55.23 ± 12.89

51.52 ± 13.09

53.36 ± 13.07

0.128

Age strata, n (%)

0.285

  < 40

6 (10.5)

10 (17.2)

16 (13.9)

 40–49

12 (21.1)

12 (20.7)

24 (20.9)

 50–59

17 (29.8)

19 (32.8)

36 (31.3)

 60–69

12 (21.1)

14 (24.1)

26 (22.6)

 70–79

10 (17.5)

3 (5.2)

13 (11.3)

Female, n (%)

31 (54.39)

32 (55.17)

63 (54.78)

0.932

Occupation

0.441

 Managers

1 (1.8)

1 (1.7)

2 (1.7)

 Professionals

7 (12.3)

9 (15.5)

16 (13.9)

 Clerical support workers

8 (14.0)

7 (12.1)

15 (13.0)

 Service and sales workers

9 (15.8)

11 (19.0)

20 (17.4)

 Skilled agricultural, forestry and fishery

18 (31.6)

9 (15.5)

27 (23.5)

 Craft and related trades workers

7 (12.3)

7 (12.1)

14 (12.2)

 Elementary occupations

7 (12.3)

14 (24.1)

21 (18.3)

Mean Weight (kg), mean ± SD

87.46 ± 20.95

74.05 ± 12.76

80.71 ± 18.51

<0.001

Mean Height (m), mean ± SD

1.66 ± 0.09

1.69 ± 0.09

1.68 ± 0.09

0.054

Mean BMI, (kg/m²), mean ± SD

31.93 ± 8.67

25.80 ± 4.31

28.84 ± 7.47

<0.001

BMI Class, n (%)

<0.001

 Normal

10 (17.5)

26 (44.8)

36 (31.3)

 Overweight

12 (21.1)

27 (46.6)

39 (33.9)

 Obese

35 (61.4)

5 (8.6)

40 (34.8)

Waist circumference (cm), mean ± SD

102.19 ± 14.54

90.19 ± 9.08

96.14 ± 13.47

<0.001

High waist circumference, n (%)

37 (64.9)

25 (43.1)

62 (53.9)

0.019

Sitting height (cm), mean ± SD

81.91 ± 7.3

82.69 ± 5.37

82.30 ± 6.36

0.514

Relative sitting height, mean ± SD

49.29 ± 3.26

48.84 ± 2.88

49.07 ± 3.07

0.437

Radiographic Stenosis, n (%)

0.352

 Central

32 (56.1)

33 (56.9)

65 (56.5)

 Foraminal

23 (40.4)

25 (43.1)

48 (41.7)

 Lateral

2 (3.5)

0 (0.0)

2 (1.7)

Type of vertebra lesion, n (%)

0.073

 None

13 (22.8)

16 (27.6)

29 (25.2)

 IAJOH

33 (57.9)

24 (41.4)

57 (49.6)

 Osteophytes

8 (14.0)

18 (31.0)

26 (22.6)

 Listhesis

2 (3.5)

0 (0.0)

2 (1.7)

 Tumoral

1 (1.8)

0 (0.0)

1 (0.9)

Type of disc lesion, n (%)

0.173

 None

10 (17.5)

22 (37.9)

 IDD

8 (15.8)

10 (17.2)

 IDP

5 (8.8)

6 (10.3)

 IDH

5 (8.8)

5 (8.6)

 HP

2 (3.5)

2 (3.4)

 DDP

15 (26.3)

8 (13.8)

 DDH

11 (19.3)

5 (8.6)

Disc lesion level, n (%)

 L1-L2

2 (3.5)

0 (0.0)

2 (1.7)

0.100

 L2-L3

7 (12.3)

1 (1.7)

8 (7.0)

0.009

 L3-L4

22 (38.6)

4 (6.9)

26 (22.6)

<0.001

 L4-L5

37 (64.9)

19 (32.8)

56 (48.7)

<0.001

 L5-S1

31 (54.4)

37 (63.8)

68 (59.1)

0.556

 Multi-level

33 (57.9)

19 (32.8)

52 (45.2)

0.007

Ligamentum Flavum hypertrophy, n (%)

32 (56.1)

35 (60.3)

67 (58.3)

0.648