Table 1

Inclusion and exclusion criteria for RCT

Inclusion criteriaExclusion criteria

  • Low-back pain with or without leg pain for >1 year; if leg pain occurred, then low-back pain should dominate

  • Failure of conservative treatment scheduled for >3 months

  • Radiographic confirmation of disc degeneration on magnetic resonance imaging

  • Age 20–55 years

  • ODI ≥30 or back pain (VAS) >50/100 the week before inclusion

  • Signed informed consent

  • Patient having an open mind regarding the treatment options

  • Spinal stenosis requiring decompression

  • Moderate or worse facet joint arthritis

  • Three or more painful levels at clinical examination

  • No obvious painful level(s) at diagnostic injection evaluation (if done)

  • Isthmic spondylolysis/spondylolisthesis

  • Degenerative spondylolisthesis >3mm

  • Major deformity

  • Manifest osteoporosis—if osteoporosis was suspected because of gender and age (women aged >50 years)illness, or medication, osteoporosis should be evaluated and excluded before inclusion

  • Previous lumbar fusion or decompression with potential instability (eg, facet joint damage or wide laminectomy)

  • Compromised vertebral body

  • Previous spinal infection or tumor

  • Inability to understand information because of abuse or for psychological or medical reasons

  • Language difficulties with inability to understand follow-up instruments

  • Pregnancy or other medical condition that would be contraindication to surgery