Lumbar Spinal StenosisNORDSTEN/SSTNCT02007083

The NORDSTEN Studies/ The Spinal Stenosis Study

A study testing Bilateral laminotomy (BL), Unilateral laminotomy with crossover (UL) and Spinous Process Osteotomy (SPO) in people with Lumbar Spinal Stenosis, run by Haukeland University Hospital at 1 site in Norway.

Active, not recruiting

Under way, not looking for participants. Everyone needed has enrolled. The study is still running.

Official record

Search all trials

Trial summary

Who is it for?: Ages 18 to 80 years
Conditions the study is for: Lumbar Spinal Stenosis
What is being tested?: Bilateral laminotomy (BL), Unilateral laminotomy with crossover (UL) and Spinous Process Osteotomy (SPO)
Type of treatment: Surgery or procedure
Could I receive a placebo?: No, everyone receives an active treatment
How many people: 465 participants
Where: 1 siteNorway
Study dates: Nov 2013to Dec 2028
Phase: Interventional
Are there results?: Not yet: the study is under way

Key requirements

Who can take part, as listed by the sponsor. Only the study team can confirm whether you are eligible, so take this list to your doctor.

Ages 18 to 80 years
All sexes
No healthy volunteers
Adult, Older adult

Who may be able to join

have clinical symptoms of spinal stenosis as neurogenic claudication or radiating pain into the bilaterally to the lower limbs, not responding to at least 3 months of conservative treatment.
Radiological findings corresponding to the clinical symptoms of LSS. Central -stenosis, or lateral recess-stenosis.
be able to give informed consent and to answer the questionnaires.
over 18 years of age-have -not responding to at least 3 months of non-surgical treatment.
be able to understand Norwegian language, spoken and in writing

Who cannot join

have a degenerative lumbar spondylolisthesis, with a slip ≥ 3 mm verified on standing plain x-rays in lateral view.
are not willing to give written consent.
have former surgery in the level of stenosis.
fracture, or former fusion of the thoracolumbal region.
cauda equina syndrome (bowel or bladder dysfunction) or fixed complete motor deficit.
are ASA- classified 4 or 5.

Show all 12Show fewer

are older than 80 years
have a lumbosacral scoliosis more than 20 degrees verified on AP-view
have distinct symptoms in one or both of their legs due to other diseases, e.g. polyneuropaty, vascular claudication or osteoarthtris.
LSS in 4 or more levels.
not able to comply fully with the protocol, including treatment, follow-up or study procedures (psychosocially, mentally and physical).
the patient is participating in another clinical trial that may interfere with this trial

Trial locations and contacts

1 site in 1 country.

Norway1 site

Haukeland University Hospital
Bergen, Hagevik, 5217

Other trials in Norway

About this study

Official title: Comparison of Different Surgical Treatments for Lumbar Spinal Stenosis. A Randomized Controlled Trial Comparing the Clinical and Radiological Results Using "Spinous Process Osteotomy", "Bilateral Laminotomy" and "Unilateral Laminotomy With Crossover"

Lumbar Spinal Stenosis (LSS) is a clinical entity were narrowing of the spinal canal gives a compression of the the neural and vascular structures in the spinal canal. This often gives neurogenic claudication and sometimes severe Low Back Pain (LBP). Surgery for LSS is today the most often performed procedure in the adult lumbar spine. Beneficial effect of surgical treatment is well documented by several clinical trials, and a Cochrane review article from 2005 concludes that surgical treatment is superior to non-surgical treatment. The surgical solution is to decompress the stenotic part of the lumbar spine. There is no consensus in the literature of which surgical method that gives best long term clinical results. The investigators are therefore planning a Randomized Controlled Trial, where they will compare clinical and radiological results of three different surgical methods for LSS. The main outcome of this study is to answer which surgical method that gives the best long term clinical results. And, secondary outcome is to find out how much increase of the Dural Sac Cross Sectional Area is needed to give a long time relief of the patients' symptoms.

Conditions: Lumbar Spinal Stenosis
Being tested: Bilateral laminotomy (BL), Unilateral laminotomy with crossover (UL), Spinous Process Osteotomy (SPO)
Keywords: Lumbar Spinal stenosis, Surgical treatment of LSS.
Medical subject headings: Spinal Stenosis

What participants receive

What participants receive. In a randomised study each person is assigned to one group by chance.

Bilateral laminotomy (BL)Procedure or surgery
Also called Fenestration procedures., Multiple laminotomies.
Unilateral laminotomy with crossover (UL)Procedure or surgery
Also called microdecompression.
Spinous Process Osteotomy (SPO)Procedure or surgery
Also called Laminarthrectomi., Micro Spinous Process Osteotomy

Study groups in NCT02007083
Study group	Role	What they receive
Bilateral laminotomy (BL)	Active comparator	The multifidus muscles is detached from the spinous process bilaterally.The decompression of the spinal canal is performed by first doing a flavectomy. Thereby performing a laminotomy (about 1/3) of the the lower part of the superior lamina, and a laminotomy of the upper part (about 1/4) of the inferior lamina. This is performed bilaterally. Receives: Procedure: Bilateral laminotomy (BL)
Unilateral laminotomy with crossover (UL)	Active comparator	The multifidus muscles is detached from the spinous process unilaterally. The laminotomy is first performed ipsilaterally. The decompression of the spinal canal is performed by first doing a flavectomy. Then, performing a laminotomy (about 1/3) of the the lower part of the superior lamina, and a laminotomy of the upper part (about 1/4) of the inferior lamina. Dura is then retracted, and the decompression is performed contralaterally. Receives: Procedure: Unilateral laminotomy with crossover (UL)
Spinous process osteotomy (SPO)	Active comparator	The multifidus muscles is detached from the spinous process unilaterally. An osteotomy of the superior spinous process is performed at the basis, in the actual level. The spinous process with intact interspinal and supraspinal ligaments is then retracted to the contralateral side. The decompression is first performed in the midline. Then one goes laterally on both sides too perform the decompression. About 1/3 of the lower part of the superior lamina is removed, and about 1/4 of the upper part of the inferior lamina is removed. Receives: Procedure: Spinous Process Osteotomy (SPO)

What is being measured

The primary outcome is the main question the study is designed to answer.

Oswestry Disability Index
The investigators will monitor the ODI-index before and after surgery, and calculate the change of ODI after surgery compared to baseline.
The primary outcome is a measurement of the change of ODI (version 2.0) from baseline in the three different surgical groups. This will be done by calculating the mean ODI improvement in each group. The investigators will also compare the proportion of "success patients" between the SPO group, the BL group and the UL group, 24 months after the operation. The investigators will dichotomize the patients, in a "succesful outcome group" and in a "non- succesful outcome group". The threshold value for being categorized as a "succesful outcome" will be computed in a planned study based on data from The Norwegian Registry for Spine Surgery (NORSpine).
The investigators also plan to asses short time results after 2 years, intermediate results after 5 years, and long time results after 10 years.
Measured: 2, 5 and 10 years after surgery

Secondary outcomes (1)

Zurich claudification Scale, Numeric Rating Scale for leg pain, Numeric Rating Scale for back pain, EQ-5D, and self evaluated effect of surgery.
All of the above mentioned questionaires are validated and reliable questionaires to asses the effect of surgical treatment. The effect of the surgical treatment is calculated by the improvement of the different scores, and thereby is an objective way to asses the effect of the surgical treatment.
The investigators plan to asses short time results after 2 years, intermediate results after 5 years, and long time results after 10 years.
Measured: 2, 5 and 10 years after surgery

Timeline

From the start of the study to its completion; the mark is today. Estimated dates are the sponsor’s plan.

Nov 2013Dec 2028

First posted10 Dec 2013 (estimated)
Study startNov 2013
Primary completionOct 2028 (estimated)
Study completionDec 2028 (estimated)

Resources

Official record on ClinicalTrials.govThe registry entry this page is built from, with its full change history.
Publications (8)Papers the sponsor has linked to this study.
Other trials for Lumbar Spinal StenosisStudies of the same condition, open and under way.
What the trial phases meanHow a treatment moves from first tests in people to approval.

More details

For doctors and researchers: how the study is designed, who runs it, and its registry IDs.

Study design

Study type: Interventional
Phase: Phase N/A
Primary purpose: Treatment
Allocation: Randomised
Intervention model: Parallel groups
Masking: Single blind
Who is masked: Outcomes assessor
Enrolment: 465 participants (estimated)

IDs, dates and publications

ClinicalTrials.gov ID: NCT02007083
Sponsor's protocol ID: 2011/2034
Other IDs: 2011/2034
Acronym: NORDSTEN/SST
Status last verified: Aug 2020
First submitted: 22 Nov 2013
Last updated: 12 Aug 2020
Results posted: No
Data monitoring committee: Yes

Publications

Indrekvam K, Myklebust TA, Austevoll IM, Hermansen E, Banitalebi H, Banerud IF, Weber C, Brisby H, Brox JI, Hellum C, Storheim K. Responsiveness of the Oswestry Disability Index and Zurich Claudication Questionnaire in patients with lumbar spinal stenosis: evaluation of surgically treated patients from the NORDSTEN study. Eur Spine J. 2024 Nov;33(11):4270-4280. doi: 10.1007/s00586-024-08440-1. Epub 2024 Aug 13.
PubMed 39134699
Aaen J, Banitalebi H, Austevoll IM, Hellum C, Storheim K, Myklebust TA, Anvar M, Weber C, Solberg T, Grundnes O, Brisby H, Indrekvam K, Hermansen E. Is the presence of foraminal stenosis associated with outcome in lumbar spinal stenosis patients treated with posterior microsurgical decompression. Acta Neurochir (Wien). 2023 Aug;165(8):2121-2129. doi: 10.1007/s00701-023-05693-5. Epub 2023 Jul 5.
PubMed 37407851
Indrekvam K, Banerud IF, Hermansen E, Austevoll IM, Rekeland F, Guddal MH, Solberg TK, Brox JI, Hellum C, Storheim K. The Norwegian degenerative spondylolisthesis and spinal stenosis (NORDSTEN) study: study overview, organization structure and study population. Eur Spine J. 2023 Dec;32(12):4162-4173. doi: 10.1007/s00586-023-07827-w. Epub 2023 Jul 3.
PubMed 37395780
Hermansen E, Austevoll IM, Hellum C, Storheim K, Myklebust TA, Aaen J, Banitalebi H, Anvar M, Rekeland F, Brox JI, Franssen E, Weber C, Solberg TK, Furunes H, Grundnes O, Brisby H, Indrekvam K. Comparison of 3 Different Minimally Invasive Surgical Techniques for Lumbar Spinal Stenosis: A Randomized Clinical Trial. JAMA Netw Open. 2022 Mar 1;5(3):e224291. doi: 10.1001/jamanetworkopen.2022.4291.
PubMed 35344046
Banitalebi H, Espeland A, Anvar M, Hermansen E, Hellum C, Brox JI, Myklebust TA, Indrekvam K, Brisby H, Weber C, Aaen J, Austevoll IM, Grundnes O, Negard A. Reliability of preoperative MRI findings in patients with lumbar spinal stenosis. BMC Musculoskelet Disord. 2022 Jan 15;23(1):51. doi: 10.1186/s12891-021-04949-4.
PubMed 35033042
Aaen J, Austevoll IM, Hellum C, Storheim K, Myklebust TA, Banitalebi H, Anvar M, Brox JI, Weber C, Solberg T, Grundnes O, Brisby H, Indrekvam K, Hermansen E. Clinical and MRI findings in lumbar spinal stenosis: baseline data from the NORDSTEN study. Eur Spine J. 2022 Jun;31(6):1391-1398. doi: 10.1007/s00586-021-07051-4. Epub 2021 Nov 19.
PubMed 34797405
Hermansen E, Austevoll IM, Hellum C, Storheim K, Myklebust TA, Aaen J, Banitalebi H, Anvar M, Rekeland F, Brox JI, Franssen E, Weber C, Solberg T, Haug KJ, Grundnes O, Brisby H, Indrekvam K. Comparable increases in dural sac area after three different posterior decompression techniques for lumbar spinal stenosis: radiological results from a randomized controlled trial in the NORDSTEN study. Eur Spine J. 2020 Sep;29(9):2254-2261. doi: 10.1007/s00586-020-06499-0. Epub 2020 Jun 18.
PubMed 32556585
Hermansen E, Austevoll IM, Romild UK, Rekeland F, Solberg T, Storheim K, Grundnes O, Aaen J, Brox JI, Hellum C, Indrekvam K. Study-protocol for a randomized controlled trial comparing clinical and radiological results after three different posterior decompression techniques for lumbar spinal stenosis: the Spinal Stenosis Trial (SST) (part of the NORDSTEN Study). BMC Musculoskelet Disord. 2017 Mar 21;18(1):121. doi: 10.1186/s12891-017-1491-7.
PubMed 28327114

Want to know more?

The sponsor has not listed a contact. The official record may have more details.

Talk to your doctor first and take this page with you. Only the study team can confirm whether you can join.

Questions to ask the study team

What is the study trying to find out?
What would I need to do, and how often would I visit?
Could I receive a placebo instead of the treatment?
What are the possible risks and benefits for me?
Will it cost me anything? Are travel or time paid for?
Can I keep seeing my own doctor during the study?
What happens when the study ends?

See locations

Recruiting
Surgical Treatment of Adjacent Segment Stenosis
Adjacent Segment Disease, Lumbar Spinal Stenosis
Not yet recruiting
Kore Fiber PLF Study
Degenerative Lumbar Spine Diseases, Lumbar Degenerative Disc Disease
Recruiting
Activity Post Spinal Surgery Engagement Trial
Spinal Surgery for Lumbar Spinal Stenosis (LSS)
Active, not recruiting
SLIP II Registry: Spinal Laminectomy Versus Instrumented Pedicle Screw Fusion
Lumbar Spondylolisthesis, Grade 1 Spondylolisthesis
RecruitingObservational study
MILD® Percutaneous Image-Guided Lumbar Decompression: A Medicare Claims Study
Lumbar Spinal Stenosis

All Lumbar Spinal Stenosis trials

Study at a glance

From the registry record, last updated by the sponsor on 12 Aug 2020. Recruitment status is as the sponsor reported it: confirm with the study team.

Official title: Comparison of Different Surgical Treatments for Lumbar Spinal Stenosis. A Randomized Controlled Trial Comparing the Clinical and Radiological Results Using "Spinous Process Osteotomy", "Bilateral Laminotomy" and "Unilateral Laminotomy With Crossover"
ClinicalTrials.gov ID: NCT02007083
Acronym / sponsor ID: NORDSTEN/SST / 2011/2034
Conditions: Lumbar Spinal Stenosis
Keywords: Lumbar Spinal stenosis, Surgical treatment of LSS.
Study type: Interventional
Recruitment status: Active, not recruiting
Enrolment: 465 participants (estimated)
Lead sponsor: Haukeland University HospitalUniversity, hospital or other
Collaborators: Møre og Romsdal Hospital Trust
Study start: Nov 2013 (actual)
Primary completion: Oct 2028 (estimated)
Study completion: Dec 2028 (estimated)
First posted: 10 Dec 2013 (estimated)
Results: Not posted in the source record

Clinical summary

The research question as the sponsor registered it. This describes what the study plans to test, not what it found.

Study design

Primary purpose: Treatment
Allocation: Randomised
Intervention model: Parallel groups
Masking: Single blind (outcomes assessor)
Number of arms: 3

Arm	Type	Receives
Bilateral laminotomy (BL)	Active comparator	Procedure: Bilateral laminotomy (BL)The multifidus muscles is detached from the spinous process bilaterally.The decompression of the spinal canal is performed by first doing a flavectomy. Thereby performing a laminotomy (about 1/3) of the the lower part of the superior lamina, and a laminotomy of the upper part (about 1/4) of the inferior lamina. This is performed bilaterally.
Unilateral laminotomy with crossover (UL)	Active comparator	Procedure: Unilateral laminotomy with crossover (UL)The multifidus muscles is detached from the spinous process unilaterally. The laminotomy is first performed ipsilaterally. The decompression of the spinal canal is performed by first doing a flavectomy. Then, performing a laminotomy (about 1/3) of the the lower part of the superior lamina, and a laminotomy of the upper part (about 1/4) of the inferior lamina. Dura is then retracted, and the decompression is performed contralaterally.
Spinous process osteotomy (SPO)	Active comparator	Procedure: Spinous Process Osteotomy (SPO)The multifidus muscles is detached from the spinous process unilaterally. An osteotomy of the superior spinous process is performed at the basis, in the actual level. The spinous process with intact interspinal and supraspinal ligaments is then retracted to the contralateral side. The decompression is first performed in the midline. Then one goes laterally on both sides too perform the decompression. About 1/3 of the lower part of the superior lamina is removed, and about 1/4 of the upper part of the inferior lamina is removed.

Who may qualify

Ages: 18 to 80 years
Sex: All
Healthy volunteers: Not accepted
Age groups: Adult, Older adult

Key inclusion criteria (5 listed)

have clinical symptoms of spinal stenosis as neurogenic claudication or radiating pain into the bilaterally to the lower limbs, not responding to at least 3 months of conservative treatment.
Radiological findings corresponding to the clinical symptoms of LSS. Central -stenosis, or lateral recess-stenosis.
be able to give informed consent and to answer the questionnaires.
over 18 years of age-have -not responding to at least 3 months of non-surgical treatment.
be able to understand Norwegian language, spoken and in writing

Key exclusion criteria (12 listed)

have a degenerative lumbar spondylolisthesis, with a slip ≥ 3 mm verified on standing plain x-rays in lateral view.
are not willing to give written consent.
have former surgery in the level of stenosis.
fracture, or former fusion of the thoracolumbal region.
cauda equina syndrome (bowel or bladder dysfunction) or fixed complete motor deficit.

Eligibility is decided by the study team after screening; this overview does not establish that a patient qualifies. Full inclusion and exclusion criteria.

Interventions

Intervention	Type	Arms
Bilateral laminotomy (BL)Also: Fenestration procedures., Multiple laminotomies.	Procedure or surgery	Bilateral laminotomy (BL)
Unilateral laminotomy with crossover (UL)Also: microdecompression.	Procedure or surgery	Unilateral laminotomy with crossover (UL)
Spinous Process Osteotomy (SPO)Also: Laminarthrectomi., Micro Spinous Process Osteotomy	Procedure or surgery	Spinous process osteotomy (SPO)

Primary outcome

Oswestry Disability Index
Time frame: 2, 5 and 10 years after surgery
The investigators will monitor the ODI-index before and after surgery, and calculate the change of ODI after surgery compared to baseline. The primary outcome is a measurement of the change of ODI (version 2.0) from baseline in the three different surgical groups. This will be done by calculating the mean ODI improvement in each group. The investigators will also compare the proportion of "success patients" between the SPO group, the BL group and the UL group, 24 months after the operation. The investigators will dichotomize the patients, in a "succesful outcome group" and in a "non- succesful outcome group". The threshold value for being categorized as a "succesful outcome" will be computed in a planned study based on data from The Norwegian Registry for Spine Surgery (NORSpine). The investigators also plan to asses short time results after 2 years, intermediate results after 5 years, and long time results after 10 years.

1 secondary outcome

Zurich claudification Scale, Numeric Rating Scale for leg pain, Numeric Rating Scale for back pain, EQ-5D, and self evaluated effect of surgery.
Time frame: 2, 5 and 10 years after surgery

Results and safety

This study is still under way. Results are not available in the source record yet.

Research links

Official record on ClinicalTrials.govLast updated by the sponsor 12 Aug 2020.
Derived from this study: PubMed 39134699Indrekvam K, Myklebust TA, Austevoll IM, Hermansen E, Banitalebi H, Banerud IF, Weber C, Brisby H, Brox JI, Hellum C, Storheim K. Responsiveness of the Oswestry Disability Index and Zurich Claudication Questionnaire in patients with lumbar spinal stenosis: evaluation of surgically treated patients from the NORDSTEN study. Eur Spine J. 2024 Nov;33(11):4270-4280. doi: 10.1007/s00586-024-08440-1. Epub 2024 Aug 13.
Derived from this study: PubMed 37407851Aaen J, Banitalebi H, Austevoll IM, Hellum C, Storheim K, Myklebust TA, Anvar M, Weber C, Solberg T, Grundnes O, Brisby H, Indrekvam K, Hermansen E. Is the presence of foraminal stenosis associated with outcome in lumbar spinal stenosis patients treated with posterior microsurgical decompression. Acta Neurochir (Wien). 2023 Aug;165(8):2121-2129. doi: 10.1007/s00701-023-05693-5. Epub 2023 Jul 5.
Derived from this study: PubMed 37395780Indrekvam K, Banerud IF, Hermansen E, Austevoll IM, Rekeland F, Guddal MH, Solberg TK, Brox JI, Hellum C, Storheim K. The Norwegian degenerative spondylolisthesis and spinal stenosis (NORDSTEN) study: study overview, organization structure and study population. Eur Spine J. 2023 Dec;32(12):4162-4173. doi: 10.1007/s00586-023-07827-w. Epub 2023 Jul 3.
Derived from this study: PubMed 35344046Hermansen E, Austevoll IM, Hellum C, Storheim K, Myklebust TA, Aaen J, Banitalebi H, Anvar M, Rekeland F, Brox JI, Franssen E, Weber C, Solberg TK, Furunes H, Grundnes O, Brisby H, Indrekvam K. Comparison of 3 Different Minimally Invasive Surgical Techniques for Lumbar Spinal Stenosis: A Randomized Clinical Trial. JAMA Netw Open. 2022 Mar 1;5(3):e224291. doi: 10.1001/jamanetworkopen.2022.4291.
Derived from this study: PubMed 35033042Banitalebi H, Espeland A, Anvar M, Hermansen E, Hellum C, Brox JI, Myklebust TA, Indrekvam K, Brisby H, Weber C, Aaen J, Austevoll IM, Grundnes O, Negard A. Reliability of preoperative MRI findings in patients with lumbar spinal stenosis. BMC Musculoskelet Disord. 2022 Jan 15;23(1):51. doi: 10.1186/s12891-021-04949-4.
Derived from this study: PubMed 34797405Aaen J, Austevoll IM, Hellum C, Storheim K, Myklebust TA, Banitalebi H, Anvar M, Brox JI, Weber C, Solberg T, Grundnes O, Brisby H, Indrekvam K, Hermansen E. Clinical and MRI findings in lumbar spinal stenosis: baseline data from the NORDSTEN study. Eur Spine J. 2022 Jun;31(6):1391-1398. doi: 10.1007/s00586-021-07051-4. Epub 2021 Nov 19.
Derived from this study: PubMed 32556585Hermansen E, Austevoll IM, Hellum C, Storheim K, Myklebust TA, Aaen J, Banitalebi H, Anvar M, Rekeland F, Brox JI, Franssen E, Weber C, Solberg T, Haug KJ, Grundnes O, Brisby H, Indrekvam K. Comparable increases in dural sac area after three different posterior decompression techniques for lumbar spinal stenosis: radiological results from a randomized controlled trial in the NORDSTEN study. Eur Spine J. 2020 Sep;29(9):2254-2261. doi: 10.1007/s00586-020-06499-0. Epub 2020 Jun 18.
Derived from this study: PubMed 28327114Hermansen E, Austevoll IM, Romild UK, Rekeland F, Solberg T, Storheim K, Grundnes O, Aaen J, Brox JI, Hellum C, Indrekvam K. Study-protocol for a randomized controlled trial comparing clinical and radiological results after three different posterior decompression techniques for lumbar spinal stenosis: the Spinal Stenosis Trial (SST) (part of the NORDSTEN Study). BMC Musculoskelet Disord. 2017 Mar 21;18(1):121. doi: 10.1186/s12891-017-1491-7.

Related trials for Lumbar Spinal Stenosis

Recruiting
Surgical Treatment of Adjacent Segment Stenosis
Adjacent Segment Disease, Lumbar Spinal Stenosis
Not yet recruiting
Kore Fiber PLF Study
Degenerative Lumbar Spine Diseases, Lumbar Degenerative Disc Disease
Recruiting
Activity Post Spinal Surgery Engagement Trial
Spinal Surgery for Lumbar Spinal Stenosis (LSS)
Active, not recruiting
SLIP II Registry: Spinal Laminectomy Versus Instrumented Pedicle Screw Fusion
Lumbar Spondylolisthesis, Grade 1 Spondylolisthesis
RecruitingObservational study
MILD® Percutaneous Image-Guided Lumbar Decompression: A Medicare Claims Study
Lumbar Spinal Stenosis

Referral and contact

AzTrials does not enrol participants or take referrals. Contact the study team or a site listed below; they decide who can take part. This study is not recruiting at the moment.

Kari Indrekvam Indrekvam, MD, Dr Med study director

The Coastal Hospital of Hagevik, Orthopeadic Clinic, Haukeland University City

1 site in 1 country: see every site and its status.

Questions about this trial

What is this clinical trial studying?

The full registered description is in the About this study section and the official record.

Who may be eligible to take part?

The sponsor lists 5 inclusion and 12 exclusion criteria. Eligibility is decided by the study team after screening, so read the full criteria and contact a listed site.

Is this clinical trial currently recruiting?

The record says: under way, not looking for participants, as of the sponsor's last update on 12 Aug 2020. Status can change between updates, so confirm with the study contact before making plans.

Where is the study taking place?

The record lists 1 site in Norway. Whether a site is taking part right now should be confirmed with that site. See every site.

What are the possible benefits and risks?

They depend on the study and the treatment, and no study can promise a benefit. The study team explains the known risks during informed consent, before anyone joins; the record itself does not list them.

Are results available for this study?

This study is still under way. Results are not available in the source record yet.

How can a doctor refer a patient or contact the research team?

The record lists no contact. The official record names the sponsor, who can be asked directly. AzTrials does not enrol participants or take referrals.

What does the primary outcome measure?

Oswestry Disability Index (time frame: 2, 5 and 10 years after surgery). It is what the study was designed to measure, not a finding.

Where can I read the original study information?

On the ClinicalTrials.gov record for NCT02007083, which also lists 8 linked publications.

Does a listing mean the treatment is approved or proven to work?

No. A listing means the study is registered. It does not show that the treatment is safe, works, or is approved by a regulator.

How often is this information updated?

AzTrials copies changed records from ClinicalTrials.gov every night and reloads the whole registry every week. The sponsor last updated this record on 12 Aug 2020.