Send to

Choose Destination
BMC Musculoskelet Disord. 2019 Jan 5;20(1):7. doi: 10.1186/s12891-018-2384-0.

Decompression alone versus decompression with instrumental fusion the NORDSTEN degenerative spondylolisthesis trial (NORDSTEN-DS); study protocol for a randomized controlled trial.

Author information

Kysthospitalet in Hagevik, Orthopedic Clinic, Haukeland University Hospital, Hagavik, N- 5217, Bergen, Norway.
Department of Clinical Medicine, University of Bergen, N- 5007, Bergen, Norway.
Kysthospitalet in Hagevik, Orthopedic Clinic, Haukeland University Hospital, Hagavik, N- 5217, Bergen, Norway.
Department of Clinical Medicine, University of Bergen, N- 5007, Bergen, Norway.
Department of Orthopedic Surgery, Ålesund Hospital, Møre and Romsdal Hospital Trust, N-6026, Ålesund, Norway.
Oslo Centre for Biostatistics and Epidemiology, Research Support Services, Oslo University Hospital, N-0424, Oslo, Norway.
Department of Neurosurgery, University Hospital of Northern Norway, N-9019, Tromsø, Norway.
Department of Clinical Medicine, University of Tromsø - The Arctic University of Norway, N-9019, Tromsø, Norway.
The Norwegian Registry for Spine Surgery (NORspine), Northern Norway Regional Health Authority, N-9038, Tromsø, Bodø, Norway.
Research and Communication Unit for Musculoskeletal Health (FORMI), Oslo University Hospital, N-0424, Oslo, Oslo, Norway.
Department of Physical Medicine and Rehabilitation, Oslo University Hospital, N-0424, Oslo, Norway.
Department of Orthopedic Surgery, Innlandet Hospital Trust, N-2609, Lillehammer, Lillehammer, Norway.
Department of Research, Levanger Hospital, Nord-Trøndelag Hospital Trust, N-7600, Levanger, Norway.
Department of Orthopedics, Akershus University Hospital, N-1474, Lørenskog, Oslo, Norway.
Division of Orthopaedic Surgery, Oslo University Hospital, N-0424, Oslo, Norway.



Fusion in addition to decompression has become the standard treatment for lumbar spinal stenosis with degenerative spondylolisthesis (DS). The evidence for performing fusion among these patients is conflicting and there is a need for further investigation through studies of high quality. The present protocol describes an ongoing study with the primary aim of comparing the outcome between decompression alone and decompression with instrumented fusion. The secondary aim is to investigate whether predictors can be used to choose the best treatment for an individual. The trial, named the NORDSTEN-DS trial, is one of three studies in the Norwegian Degenerative Spinal Stenosis (NORDSTEN) study.


The NORDSTEN-DS trial is a block-randomized, controlled, multicenter, non-inferiority study with two parallel groups. The surgeons at the 15 participating hospitals decide whether a patient is eligible or not according to the inclusion and exclusion criteria. Participating patients are randomized to either a midline preserving decompression or a decompression followed by an instrumental fusion. Primary endpoint is the percentage of patients with an improvement in Oswestry Disability Index version 2.0 of more than 30% from baseline to 2-year follow-up. Secondary outcome measurements are the Zürich Claudication Questionnaire, Numeric Rating Scale for back and leg pain, Euroqol 5 dimensions questionnaire, Global perceived effect scale, complications and several radiological parameters. Analysis and interpretation of results will also be conducted after 5 and 10 years.


The NORDSTEN/DS trial has the potential to provide Level 1 evidence of whether decompression alone should be advocated as the preferred method or not. Further on the study will investigate whether predictors exist and if they can be used to make the appropriate choice for surgical treatment for this patient group.

TRIAL REGISTRATION: Identifier: NCT02051374 . First Posted: January 31, 2014. Last Update Posted: February 14, 2018.


Clinical outcomes; Decompression; Degenerative spondylolisthesis; Fusion; NORDSTEN; Randomized controlled trial; Spinal stenosis

Supplemental Content

Full text links

Icon for BioMed Central Icon for PubMed Central Icon for Norwegian BIBSYS system
Loading ...
Support Center