Lumbar Spine Stenosis Central Canal
Conditions
Keywords
Lumbar Spine Stenosis, Decompression
Brief summary
This is a single-center, randomized, prospective, double-blind, clinical study to assess the clinical application and outcomes with mild® devices versus sham in patients with symptomatic moderate to severe central canal spinal stenosis. Sham patients were eligible to choose to cross-over and have the actual decompression procedure after week 6 exam.
Interventions
Fluoroscopic percutaneous lumbar decompression of the central spinal canal
DEVICESham lumbar decompression
Sham fluoroscopic percutaneous lumbar decompression with no bone or tissue removal.
Sponsors
Vertos Medical, Inc.
Napa Pain Institute
Study design
Allocation
RANDOMIZED
Intervention model
PARALLEL
Primary purpose
TREATMENT
Masking
TRIPLE (Subject, Caregiver, Outcomes Assessor)
Eligibility
Sex/Gender
ALL
Age
18 Years to No maximum
Healthy volunteers
No
Inclusion criteria
* Symptomatic and lumbar spine stenosis (LSS) primarily caused by dorsal element hypertrophy. * Prior failure of conservative therapy and Oswestry Disability Index (ODI) Score of \>20%. * Radiologic evidence of LSS, ligamentum flavum hypertrophy (typically \> 2.5mm)confirmed by pre op MRI and/or CT. * Central canal cross sectional area clearly reduced per MRI/CT report. * If present, anterior listhesis ≤ 5.0mm (preferred) and stable. * Able to walk at least 10 feet unaided before being limited by pain. * Available to complete 26 weeks of follow-up. * A signed Informed consent Form is obtained from the subject. * Adults at least 18 years of age.
Exclusion criteria
* Prior surgery at intended treatment level. * History of recent spinal fractures with concurrent pain symptoms as determined by the Investigator. * Disabling back or leg pain from causes other than LSS (e.g. acute compression fracture, metabolic neuropathy, or vascular claudication symptoms, etc.). * Disk protrusion or osteophyte formation severe enough to confound study outcome. * Facet hypertrophy severe enough to confound study outcome. * Bleeding disorders and/or current use of anti-coagulants. * Use of acetylsalicylic acid (ASA) and/or non-steroidal anti-inflammatory (NSAID) within five days of treatment. * Epidural steroid administration within prior 3 weeks(of procedure or sham) * Inability of the subject to lie prone for any reason with anesthesia support (e.g. chronic obstructive pulmonary disease (COPD), obesity, etc.). * Metabolic wound healing pathologies deemed by Investigator to compromise study outcome. * Dementia and/or inability to give informed consent. * Pregnancy and/or breastfeeding. * On Workman's Compensation or considering litigation associated with back pain.
Design outcomes
Primary
| Measure | Time frame | Description |
|---|---|---|
| Visual Analog Scale (VAS) <=4 | Week 6 to 12 prior to cross-over | Using VAS, pain is measured on a 0 to 10 point scale where 0 represents no pain and 10 indicates severe pain. A post-treatment score of 4 points is the accepted threshold between a mild pain score of 1-3 points and a moderate to severe pain score of 5 to 10 points which represents debilitating pain that would qualify the patient for a different or additional treatment option. All patients in each arm who reported a pain score of 4 or less at six to twelve weeks post-treatment are reported below. |
| Visual Analog Scale (VAS) Mean Improvement | Baseline and Year 1 | VAS ten point scale where 0 = no pain and 10 represents worst pain imaginable. Mean improvement of two or more points is considered clinically relevant. The mean improvement from Baseline to Year-1 is presented below for the two treatment groups. |
Countries
United States
Participant flow
Recruitment details
Recruitment occurred 4-19-10 to 7-28-10
Pre-assignment details
Randomization occurred in blocks of four. After Week 6 post-treatment and prior to Week 12, Sham arm participants were allowed to have the mild decompression procedure with bone and tissue removal if they chose to have it.
Participants by arm
| Arm | Count |
|---|---|
| Mild Procedure Group 1: mild percutaneous decompression with removal of bone and tissue | 20 |
| Sham Procedure Group 2: sham decompression with trocar placement and no bone or tissue removal | 20 |
| Total | 40 |
Withdrawals & dropouts
| Period | Reason | FG000 | FG001 |
|---|---|---|---|
| After Sham Cross-over to Mild, One Year | Lack of Efficacy | 0 | 1 |
| After Sham Cross-over to Mild, One Year | Lost to Follow-up | 2 | 1 |
| After Sham Cross-over to Mild, One Year | pancreatic cancer progressed | 0 | 1 |
| After Sham Cross-over to Mild, One Year | Withdrawal by Subject | 0 | 4 |
Baseline characteristics
| Characteristic | Sham Procedure | Mild Procedure | Total |
|---|---|---|---|
| Age, Categorical <=18 years | 0 Participants | 0 Participants | 0 Participants |
| Age, Categorical >=65 years | 12 Participants | 13 Participants | 25 Participants |
| Age, Categorical Between 18 and 65 years | 8 Participants | 7 Participants | 15 Participants |
| Age Continuous | 67 years STANDARD_DEVIATION 12.5 | 66.3 years STANDARD_DEVIATION 10.8 | 66.6 years STANDARD_DEVIATION 11.5 |
| Region of Enrollment United States | 20 participants | 20 participants | 40 participants |
| Sex: Female, Male Female | 7 Participants | 10 Participants | 17 Participants |
| Sex: Female, Male Male | 13 Participants | 10 Participants | 23 Participants |
Adverse events
| Event type | EG000 affected / at risk | EG001 affected / at risk |
|---|---|---|
| deaths Total, all-cause mortality | — / — | — / — |
| other Total, other adverse events | 0 / 20 | 0 / 20 |
| serious Total, serious adverse events | 0 / 20 | 0 / 20 |
Outcome results
Primary
Visual Analog Scale (VAS) <=4
Using VAS, pain is measured on a 0 to 10 point scale where 0 represents no pain and 10 indicates severe pain. A post-treatment score of 4 points is the accepted threshold between a mild pain score of 1-3 points and a moderate to severe pain score of 5 to 10 points which represents debilitating pain that would qualify the patient for a different or additional treatment option. All patients in each arm who reported a pain score of 4 or less at six to twelve weeks post-treatment are reported below.
Time frame: Week 6 to 12 prior to cross-over
Population: All 40 participants (20 in each arm) reported VAS at six weeks to twelve weeks post-treatment. All measurements for the sham group occurred prior to cross-over to the mild procedure. Patients with scores of 4 or less in each study group are reported below. This is Intent to Treat (ITT)analysis.
| Arm | Measure | Value (NUMBER) | Dispersion |
|---|---|---|---|
| Mild Procedure Group 1 | Visual Analog Scale (VAS) <=4 | 11 participants | 2.1 |
| Sham Procedure Group 2 Prior to Cross-over | Visual Analog Scale (VAS) <=4 | 2 participants | 1.8 |
Primary
Visual Analog Scale (VAS) <=4
VAS as measured on a 10-point scale. A score of 4 or less after treatment is considered favorable, as it indicates pain is less than the moderate to severe categories represented by scores of 5 to 10. All patients in each arm who reported a pain score of 4 or less at Week 6-12 and Year 1 are reported below.
Time frame: Week 6 to 12 & Year One After Sham to mild x-over
Population: Patients who reported Year 1 outcomes are reported at Week 6-12 and at Year 1. All findings reported below for the Sham group are after cross-over to mild.
| Arm | Measure | Group | Value (NUMBER) |
|---|---|---|---|
| Mild Procedure Group 1 | Visual Analog Scale (VAS) <=4 | Week 6-12 | 9 participants |
| Mild Procedure Group 1 | Visual Analog Scale (VAS) <=4 | Year 1 | 12 participants |
| Sham Procedure Group 2 Prior to Cross-over | Visual Analog Scale (VAS) <=4 | Week 6-12 | 5 participants |
| Sham Procedure Group 2 Prior to Cross-over | Visual Analog Scale (VAS) <=4 | Year 1 | 5 participants |
Primary
Visual Analog Scale (VAS) Mean Improvement
VAS ten point scale where 0 = no pain and 10 represents worst pain imaginable. Mean improvement of two or more points is considered clinically relevant. The mean improvement from Baseline to Year-1 is presented below for the two treatment groups.
Time frame: Baseline and Year 1
Population: All patients who reported Year-1 outcomes (Year-1 Cohort) were analyzed. The Sham Year-1 cohort represent those original Sham patients who crossed over from Sham to the mild procedure and were then followed for one year.
| Arm | Measure | Value (MEAN) | Dispersion |
|---|---|---|---|
| Mild Procedure Group 1 | Visual Analog Scale (VAS) Mean Improvement | 2.3 units on a scale | Standard Deviation 2.1 |
| Sham Procedure Group 2 Prior to Cross-over | Visual Analog Scale (VAS) Mean Improvement | 2.2 units on a scale | Standard Deviation 2.9 |