ANZCTR - Registration

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Trial registered on ANZCTR

Registration number

ACTRN12612000780853

Ethics application status

Not yet submitted

Date submitted

20/07/2012

Date registered

24/07/2012

Date last updated

24/07/2012

Type of registration

Prospectively registered

Titles & IDs

Public title

A trial comparing minimally invasive spinal surgery with open spinal surgery to treat narrowing of the spinal canal

Scientific title

Randomised Controlled Non-inferiority Trial Of Minimally Invasive Versus Standard Open Decompression For Degenerative Lumbar Canal Stenosis, comparing functional outcomes, pain scores, and complications in both procedures.

Secondary ID [1]

Nil

Universal Trial Number (UTN)

U1111-1132-8416

Trial acronym

Linked study record

Health condition

Health condition(s) or problem(s) studied:

Degenerative lumbar canal stenosis

Condition category

Condition code

Surgery

Surgical techniques

Neurological

Other neurological disorders

Musculoskeletal

Other muscular and skeletal disorders

Intervention/exposure

Study type

Interventional

Description of intervention(s) / exposure

Minimally invasive decompressive laminectomy - the hypertrophied ligamentum flavum and facets are undercut with surgical access through a small working tube, as opposed to a long midline incision. In this manner the spinal canal and neural elements are decompressed, whilst preserving the spinal extensor muscles, and the spinous processes. The procedure takes approximately 90-120 minutes of operating time.

Intervention code [1]

Treatment: Surgery

Comparator / control treatment

Standard treatment - open decompressive laminectomy. Through a midline skin incision, the lamina and spinous processes of the vertebrae are removed, and hypertrophied ligamentum flavum removed. This allows decompression of the spinal canal and neural elements. An open decompressive laminectomy takes approximately 90-120 minutes of operating time.

Open decompressive laminectomy has been shown to be superior to non-surgical treatment in previous randomised trials, but has not been directly compared to the newer minimally invasive techniques.

Control group

Active

Outcomes

Primary outcome [1]

Oswestry Disability Index at 6 months post operatively

Timepoint [1]

6 months post op

Secondary outcome [1]

Post operative pain - Visual Analogue Score

Timepoint [1]

One day post operatively

Secondary outcome [2]

Operative complications
1. Intraoperative dural tear - as observed at theatre
2. Post operative CSF leak - if clinically observed in post operative
period.
3. Post operative infection - diagnosied clinically, and if necessary with post operative blood tests and/or MRI imaging
4. Blood transfusion requirements - retrieved from the medical record of the inpatient episode
5. Second surgical procedure at the operative level - retrieved from the medical record of the inpatient episode
6. Post operative spondylolisthesis - diagnosed on post operative MRI and X-ray

Timepoint [2]

At time of intervention

Long term spondylolisthetic complications will be detected at follow up imaging at 6 months

Secondary outcome [3]

EuroQuol EQ-5D Quality of Life outcome

Timepoint [3]

4 weeks post op
6 months, 12 months, and 24 months post op

Secondary outcome [4]

Post operative MRI and X-ray at 6 months to assess extent of canal decompression, and exclude late onset of post operative spondylolisthesis or instability.

Timepoint [4]

6 months post op

Secondary outcome [5]

Oswestry Disability Index at 12 months and 24 months post op

Timepoint [5]

12 months and 24 months post op

Eligibility

Key inclusion criteria

Patients with symptomatic degenerative lumbar canal stenosis with neurogenic claudication and/or lumbar radiculopathy

Minimum age

18 Years

Maximum age

No limit

Sex

Both males and females

Can healthy volunteers participate?

Key exclusion criteria

Cauda equina syndrome
Requirement for instrumentation
Prevous lumbar spine surgery at the affected level(s)
Dependent in ADLs (Karnofsky Score <60)
Psychiatric illness
Other significant comorbidities that may affect pain scores

Study design

Purpose of the study

Treatment

Allocation to intervention

Randomised controlled trial

Procedure for enrolling a subject and allocating the treatment (allocation concealment procedures)

Randomisation by off site techniques

Methods used to generate the sequence in which subjects will be randomised (sequence generation)

Simple randomisation - "coin toss"

Masking / blinding

Blinded (masking used)

Who is / are masked / blinded?

Intervention assignment

Parallel

Other design features

Phase

Phase 3

Type of endpoint/s

Efficacy

Statistical methods / analysis

Recruitment

Recruitment status

Not yet recruiting

Date of first participant enrolment

Anticipated

1/08/2012

Actual

Date of last participant enrolment

Anticipated

Actual

Date of last data collection

Anticipated

Actual

Sample size

Target

Accrual to date

Final

Recruitment in Australia

Recruitment state(s)

Funding & Sponsors

Funding source category [1]

Self funded/Unfunded

Name [1]

Jason McMillen/Martin Wood

Address [1]

Mater Misericordiae Private Hospital
301 Vulture Street
South Brisbane Queensland 4101

Country [1]

Australia

Primary sponsor type

Individual

Name

Jason McMillen

Address

Mater Misericordiae Private Hospital
301 Vulture Street
South Brisbane Queensland 4101

Country

Australia

Secondary sponsor category [1]

None

Name [1]

Address [1]

Country [1]

Ethics approval

Ethics application status

Not yet submitted

Ethics committee name [1]

Mater Medical Research Institute Human Research Ethics Committee and Governance

Ethics committee address [1]

MMRI HREC
Level 3, Quarters Building
Mater Hospital
Raymond Terrace
South Brisbane  Qld  4101

Ethics committee country [1]

Australia

Date submitted for ethics approval [1]

22/06/2012

Approval date [1]

Ethics approval number [1]

Summary

Brief summary

Surgical decompression of the lumbar canal in patients with significant symptoms of claudication or radicular pain and a radiological diagnosis of canal stenosis is both efficacious and well tolerated, with sustained long term benefits.  Historically, lumbar canal stenosis was treated with complete laminectomy but recognition that the pathology is largely at the level of the disc and interlaminar space has led to less destructive approaches such as interlaminar decompression or laminotomy.  Despite this, all published series report some morbidity and complications from surgery in what is typically an elderly population, such as dural tear, infection, persistent back pain and the need for blood transfusion or further surgical intervention. One concern is that of post-operative spondylolisthesis, which is thought to occur from disruption of the spinous processes and interspinous ligament, observed in up to 30% in some series.

Minimally invasive techniques for decompression of the lumbar canal using a micro-endoscopic approach have been described and are growing in popularity.  Instead of a midline posterior approach to the spinal canal, where the muscles are dissected bilaterally and the posterior spinal structures removed, a minimally invasive technique uses a unilateral, paramedian approach where the muscles are preserved and surgery is carried out through an 18mm diameter working tube.  The surgical field is illuminated and magnified under the operating microscope and custom designed bayoneted instruments are employed to avoid obscuring vision.   The spinal canal is decompressed in the same way as one would using an open approach but the posterior spinal structures are largely preserved, which offers a biomechanical advantage with the potential to reduce late spondylolisthesis.  The less destructive approach should also reduce early post-operative back pain, promote more rapid mobilisation, and consequently reduce the number of inpatient hospital days.
	
There is a growing body of evidence supporting the efficacy of this technique for treating patients with lumbar canal stenosis though there are concerns over the adequacy of decompression through a small operating tube and the learning curve associated with the adoption of this less invasive but potentially more restricted technique. Thus far, a number of observational studies have implied early advantages to patients offered minimally invasive over open lumbar canal decompression, there has yet to be a properly conducted and appropriately powered randomised controlled trial to confirm that the techniques are similarly effective in terms of medium to long-term functional outcome.  A phase III non-inferiority trial design, i.e., to show that minimally invasive lumbar canal decompression is not inferior to standard open lumbar decompression, is considered to be the most stringent and statistically appropriate trial design to answer this important question.  

Trial participants will be recruited from patients undergoing elective open or minimally invasive decompressive lumbar laminectomy for degenerative lumbar canal stenosis at the Mater Misericordiae Private Hospital.  After obtaining consent for the patients’ participation in the trial, they will undergo pre-operative clinical and radiological assessment by their consultant surgeon, including MRI and X-ray lumbar spine, in the usual way.  Baseline questionnaires will be obtained pre-operatively.  After randomisation to either surgical arm, open or minimally invasive lumbar decompression surgery will proceed in the usual way.  There will be no changes to the usual surgical management of the patient resulting from the trial.

Post operative management will proceed in the usual way, with no changes to normal post operative surgical management.  Patients will complete outcome questionnaires prior to discharge.  Patients will be assessed for discharge by a physiotherapist and their surgeon, and discharged at a clinically appropriate time in the usual way.  Patients will be followed up at their routine appointment with the consultant surgeon.  Outcome questionnaires will be completed at periods up to 24 months post operatively, and a follow up X-ray and MRI lumbar spine will be obtained.  Data obtained will allow comparison of the outcomes of the two surgical procedures, including patient outcome measures, morbidity and adverse events, and radiological outcomes including extent of decompression and development of late spondylolisthesis.

Trial website

Trial related presentations / publications

Public notes

Contacts

Principal investigator

Name

Address

Country

Phone

Fax

Contact person for public queries

Name

Dr Martin Wood

Address

Suite 5.02, Fifth Floor
Mater Private Clinic
550 Vulture Street
South Brisbane Qld 4101

Country

Australia

Phone

+61 7 3163 2830

Fax

+61 7 3163 2829

[email protected]

Contact person for scientific queries

Name

Dr Martin Wood

Address

Suite 5.02, Fifth Floor
Mater Private Clinic
550 Vulture Street
South Brisbane Qld 4101

Country

Australia

Phone

+61 7 3163 2830

Fax

+61 7 3163 2829

[email protected]

No information has been provided regarding IPD availability

What supporting documents are/will be available?

No Supporting Document Provided

Results publications and other study-related documents

Documents added manually

No documents have been uploaded by study researchers.

Documents added automatically

No additional documents have been identified.

Trial Review

Documents added manually

Documents added automatically