Table 1 Background and clinical characteristics of the lumbar spinal stenosis patients preoperatively and on 3-month postoperative follow-up time n = 100

Age (years at operation, mean (SD))

62.0 (12.0)

Male/Female (n)

57/43

BMI (kg/m²) (SD)

29.4 (4.0)

Marital status (%)

64.4

In relationship (married or co-habiting)

Employment status (%), at work

13.9

Current smoker (%)

20.6

Number of somatic diseases (mean (SD))

5.4 (3.2)

Type of stenosis central/lateral

83/17

Dural sac area (mean; mm²) the most stenotic level

57.8 (32.5)

Previous lumbar operation (n)

16

Time since first back pain episode, years (mean (SD))

15.8 13.9)

Oswestry (ODI) % (mean (SD))

43.9 (15.4)

26.9 (18.6)

VAS, mm (mean (SD))

33.3 (23.9)

19.1 (22.1)

BDI score (mean (SD))

10.3 (6.0)

8.0 (5.8)

Walking capacity, metres (mean (SD))

594 (439)