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CompletedNCT04166981Updated Mar 31, 2022

Instr. vs. Non-instr. Posterolateral Spinal Fusion in Patients With Spinal Stenosis and Degenerative Listhesis

An interventional study of Instrumented posterolateral spine fusion. and Non-instrumented posterolateral spine fusion. in Spinal Stenosis, Spondylolisthesis Degenerative and Spinal Fusion, sponsored by Spine Centre of Southern Denmark. Completed at 1 site in Denmark. Open to participants aged 60 Years and older. Per ClinicalTrials.gov, last updated 2022-03-31.

Sponsored by Spine Centre of Southern Denmark · Not applicable, Interventional, and Treatment

From the registry’s dates

  • Registered 2 years 10 months after the study started (first participant enrolled Jan 2017, registered Nov 2019).
Phase
Not applicable
Study type
Interventional
Enrollment
104
Allocation
Randomized
Ages
60 Years and older
Sex
All
01

Study summary

The aim of this study is to determine, in patients with grade 1 degenerative spondylolisthesis with spinal stenosis, if decompression and lumbar spinal fusion with, or without supplementary pedicle screw fixation yields an improved patient reported outcome.

Read the detailed description

Lumbar spinal stenosis (LSS) is a common disease with a large impact on the quality of life of the patient. LSS is defined as narrowing of the spinal canal, nerve root canal or intervertebral foramina. Spinal stenosis is caused by degenerative changes in the lumbar spine, including thickening of the ligamentum flavum, osteophyte formation and disc protrusion. Pain is worse with standing upright and with exercise, and relieved with spine flexion or sitting down.

In the Wakayama Spine Study, investigators found radiographic severe spinal stenosis, defined as narrowing of more than two-thirds of the spinal canal area, in 30,4% of all patients, but only 17,5% were symptomatic.

Many of the patients suffering from LSS are pensioners, with an average age of 65 years. With current changes in demographics and the aging global population it is estimated that prevalence of LSS will increase to nearly 60% by 2025.

In a Danish epidemiological study, degenerative spondylolisthesis was found in 2,7% of men and 8,4% of women above 50 years. Every year, more than 3500 patients aged 60 and above are referred to Center of Spine Surgery Middelfart for LSS. According to the national Danish surgical spine database, DaneSpine, 7936 patients with LSS had surgery during a period from 2009-2013.

Patients suffering from LSS and instability are treated with decompression and posterolateral spinal fusion with or without instrumentation. According to DaneSpine, this group of patients showed improvements on both physical and psychological parameters. In countries outside of Scandinavia, these patients are usually treated with decompression and posterolateral spinal fusion with supplementary pedicle screw fixation. Instrumentation with pedicle screws and rods provides an internal splint, preventing motion during fusion healing. The fusion rate in non-instrumented arthrodesis is reported to be as low as 30-45% In contrast the fusion rate with instrumented arthrodesis have been reported to be above 80%. Although some studies have shown similar outcomes after decompression with or without instrumentation, long-term follow up has shown that a solid fusion improves clinical outcome.

In recent retrospective studies, the spinal sagittal balance, specifically the sagittal vertical axis (SVA) has been shown to affect the outcome of patients undergoing laminectomy. Decompression surgery has been shown to improve sagittal balance in patients with a preoperative imbalance, compared to patients treated with rehabilitation. The preoperative sagittal imbalance has not been shown to significantly affect health-related quality of life(HRQoL)outcomes although a residual imbalance after decompression is related to a poorer outcome. No prospective studies to our knowledge have compared the sagittal balance and outcomes in patients with spinal stenosis and spondylolisthesis, treated with decompression and spinal fusion with or without supplemental pedicle screw fixation.

02

Conditions studied

  • Spinal Stenosis
  • Spondylolisthesis Degenerative
  • Spinal Fusion
03

In context

Spinal Stenosis

459 studies on the registry are indexed under Spinal Stenosis; 103 are open to participants now.

This study's enrollment of 104 is above the median of 80 across 283 interventional studies indexed under Spinal Stenosis.

Browse Spinal Stenosis studies →

Lead sponsor

Spine Centre of Southern Denmark is the lead sponsor of 22 studies on the registry; 3 are open to participants now.

Counted across the registry records on this site, refreshed daily.

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Who can participate

Ages eligible
60 Years and older
Sexes eligible
All
Accepts healthy volunteers
No

Inclusion criteria

  • Patients diagnosed with Lumbar Spinal stenosis, with neurogenic claudication, radicular pain and,
  • Confirmatory MRI scan showing lumbar spinal stenosis on 1-2 levels from L1-S1
  • Standing X-ray showing grade 1 spondylolisthesis on one level
  • Age 60 and above
  • Symptom duration of 3+ months

Exclusion criteria

Exclusion Criteria:

  • Stenosis caused by herniated disc
  • Prior vertebral compression fracture in the affected segments
  • Active malignancy
  • Current fracture, infection og deformity of the spine
  • Stenosis on 3 or more levels
  • MMSE test score below 24
  • Neuromuscular disease
  • Obligatory peroral steroid treatment
  • ASA grade 3 or more.
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Study design

Phase
Not applicable
Primary purpose
Treatment
Allocation
Randomized
Intervention model
Parallel assignment
Masking
Double (Investigator, Outcomes assessor)
Enrollment
104 participants (actual)

Study arms

  • Active comparator
    Non-instrumented arm

    Decompression with concomitant non-instrumented posterolateral fusion with autologous(obtained from the decompression) and allogenic bone graft.

    Procedure: Non-instrumented posterolateral spine fusion.

  • Experimental
    Instrumented arm

    Decompression with concomitant instrumented posterolateral fusion with autologous(obtained from the decompression) and allogenic bone graft and supplementary pedicle screw fixation.

    Procedure: Instrumented posterolateral spine fusion.

Interventions

  • ProcedureInstrumented posterolateral spine fusion.

    Posterolateral fusion with autologous and allogenic bone graft with supplementary pedicle screw fixation.

    Also known as: Decompression on affected level

  • ProcedureNon-instrumented posterolateral spine fusion.

    Posterolateral fusion with autologous and allogenic bone graft.

    Also known as: Decompression on affected level

06

What researchers measure

Primary outcomes

  1. Oswestry Disability Index(ODI)

    A disease specific measure of physical disability in an index score ranging from 0-100, 0 being the best possible outcome and 100 being the worst. Comparing the effectiveness of the two arms.

    Time frame: 2 years after surgery

Secondary outcomes

  1. Achieved solid posterolateral fusion

    Fine cut CT-scans, evaluated by 3 observers to determine if solid posterolateral fusion is achieved.

    Time frame: CT-scans 1 year after surgery

  2. Change in sagittal balance, effect on outcome.

    Lateral scoliosis X-rays obtained pre operatively and after 1 and 2 years.

    Time frame: Pre operative, 1 and 2 years after surgery

  3. European Quality of life - 5 Dimensions (EQ-5D)

    Changes in quality of life in the study groups, Obtained preoperatively, after 3 months, 1 year and 2 years. Scores range between -0.6 to 1.0 where 1 is perfect health.

    Time frame: preoperative, 3, 12 and 24 months after surgery

  4. Difference in cost-effectiveness between instrumented versus non-instrumented fusion.

    Additional cost of instrumentation, incidence of revision surgery and treatment effectiveness, measured by health state utilities. Measured in Quality adjusted Life years(QaLY) and cost of surgery measured in American dollars.

    Time frame: 2 years after surgery.

Other outcomes

  1. Zurich Claudication Questionnaire

    Disease specific patient reported outcome, to measure changes in function. The result is expressed as a percentage of the maximum possible score. The score increases with worsening disability.

    Time frame: Preoperative, 1 and 2 years after surgery.

  2. NRS score for leg- and back pain.

    Patient reported leg and back pain. Obtained preoperatively, after 3 months, 1 year and 2 years. Score is 0-100, the score increases with worsening pain.

    Time frame: Properative, 1 and 2 years after surgery.

07

Study locations

1 site
  • Spine Center of Southern Denmark
    Middelfart, 5500, Denmark
08

References and documents

Individual participant data

Plan to share: Yes — All individual patient data that underlies the results reported in this article, after deidentification. (texts, tables, figures)

Supporting information: Study protocol

No publications or documents are linked to this record.

09

Updates

Tracking since Sep 25, 2026
No changes since tracking began. The registry record was last updated on Mar 31, 2022, before this site started recording changes on Sep 25, 2026. Its history is on ClinicalTrials.gov ↗
10

Registry details

Key details

Study ID
NCT04166981
Lead sponsor
Spine Centre of Southern Denmark
Responsible party
Andreas Kiilerich Andresen (Study Principal Investigator, Spine Centre of Southern Denmark) — Principal investigator
First posted
Nov 18, 2019
Start date
Jan 1, 2017
Primary completion
Dec 1, 2021
Completion
Dec 1, 2021
Last update
Mar 31, 2022

Study contacts

Andreas K Andresen, MD
principal investigator · University of Southern Denmark

Oversight

Data monitoring committee
Yes
FDA-regulated drug
No
FDA-regulated device
No
View the source record on ClinicalTrials.gov ↗

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This study is completed, as verified in Mar 2022. You cannot join it, but the record below documents what was studied.

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