Lumbar Spinal Stenosis
Conditions
Keywords
Spinal Stenosis, Lumbar Spinal Stenosis
Brief summary
This is a multi-center, prospective, patient outcomes assessment of Minimally Invasive Lumbar Decompression with the Mild® devices in patients with symptomatic central canal spinal stenosis.
Interventions
PROCEDURElumbar decompression
The mild® devices used in this study are specialized surgical instruments intended to be used to perform percutaneous lumbar decompressive procedures for the treatment of various spinal conditions.
Sponsors
Vertos Medical, Inc.
Study design
Allocation
NA
Intervention model
SINGLE_GROUP
Primary purpose
TREATMENT
Masking
NONE
Eligibility
Sex/Gender
ALL
Age
18 Years to No maximum
Healthy volunteers
No
Inclusion criteria
* Symptomatic lumbar spinal stenosis (LSS) primarily caused by dorsal element hypertrophy. * Prior failure of conservative therapy and Oswestry Disability Index (ODI) score \> 20%. * Radiologic evidence of lumbar spinal stenosis (LSS), ligamentum flavum hypertrophy (typically \> 2.5 mm), confirmed by pre-op MRI and/or CT. * Central canal cross sectional area clearly reduced per MRI/CT report. * If present, anterior listhesis preferred ≤ 5.0mm and deemed stable by Investigator. * 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 patient. * Adults at least 18 years of age.
Exclusion criteria
* Prior surgery at intended treatment level. * Compound fracture with interspinal retropulsion contributing to spinal stenosis. * Disabling back or leg pain from causes other than LSS (e.g. acute compression fracture, metabolic neuropathy, or vascular claudication symptoms, etc.). * Disc 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 drug (NSAID) within 5 days of treatment. * Epidural steroid administration within prior three weeks (of procedure). * Inability of the patient 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 outcomes. * Dementia and/or inability to give informed consent. * Pregnant and/or breastfeeding. * On Workman's Compensation or considering litigation associated with back pain.
Design outcomes
Primary
| Measure | Time frame | Description |
|---|---|---|
| Changes in Back Pain as Measured by a 10-point Visual Analog Scale (VAS). | Baseline and Month 6 | The 10-point Visual Analog Scale (VAS)rates 'no pain' as zero and 'worst pain imaginable' as ten. VAS mean improvement greater than or equal to 2 points is considered clinically relevant. The change from baseline to Month 6 is presented below where a positive value represents the baseline value minus the 6 month value. |
| Function as Measured Subjectively by the Oswestry Disability Index Questionnaire | Baseline and Month 6 | Oswestry Disability Index (ODI) measures permanent functional disability using questions regarding activities of daily living (ADL), specifically disturbance of ADL related to chronic back pain. Higher scores indicate a 'more limited' life. The ten topics of the ODI are rated from zero (no pain/limitation) to five (high pain/very limited physically). The worst possible score is 50 (100% disability) with the best score being zero (0% disability).Change from baseline to 6 months is presented below, where a positive value represents the baseline value minus the 6 month value. |
| Quality of Life Changes as Determined by Short Form 12-question (SF-12) Survey Specifically Related to Physical Component Score (PCS). | Baseline and Month 6 | The SF-12 is a validated norm-based scoring tool used to determine treatment outcomes. The PCS summary measure shows the impact of the treatment on the patients abilities to conduct their usual physical activities. Clinical relevance of PCS is established by baseline to post-treatment improvement of 2 to 3 points. Norm-based scoring is used so that each scale has the same mean (50 points) and the same standard deviation (10 points) as the general US population in 1998. Scores below 50 indicate a decline in health status, with lower scores representing worse health status. Minimally Important Difference (MID) is a measure of true clinical relevance of a difference, with suggested MID for the Physical Component Summary (PCS) being 2 to 3 points. Change from baseline to 6 months is presented, where a positive value represents the 6 month value minus the baseline value. |
Countries
United States
Participant flow
Recruitment details
Patients were enrolled from July 2008 through January 2010.
Participants by arm
| Arm | Count |
|---|---|
| Lumbar Decompression Single arm cohort having percutaneous decompression using the mild Device Kit | 55 |
| Total | 55 |
Baseline characteristics
| Characteristic | Lumbar Decompression |
|---|---|
| Age, Categorical <=18 years | 0 Participants |
| Age, Categorical >=65 years | 34 Participants |
| Age, Categorical Between 18 and 65 years | 21 Participants |
| Age Continuous | 68.3 years STANDARD_DEVIATION 12.1 |
| Region of Enrollment United States | 55 participants |
| Sex: Female, Male Female | 32 Participants |
| Sex: Female, Male Male | 23 Participants |
Adverse events
| Event type | EG000 affected / at risk |
|---|---|
| deaths Total, all-cause mortality | — / — |
| other Total, other adverse events | 0 / 55 |
| serious Total, serious adverse events | 0 / 55 |
Outcome results
Primary
Changes in Back Pain as Measured by a 10-point Visual Analog Scale (VAS).
The 10-point Visual Analog Scale (VAS)rates 'no pain' as zero and 'worst pain imaginable' as ten. VAS mean improvement greater than or equal to 2 points is considered clinically relevant. The change from baseline to Month 6 is presented below where a positive value represents the baseline value minus the 6 month value.
Time frame: Baseline and Month 6
Population: All available participants who reported Month 6 outcomes are included in this analysis.
| Arm | Measure | Value (MEAN) |
|---|---|---|
| Lumbar Decompression | Changes in Back Pain as Measured by a 10-point Visual Analog Scale (VAS). | 3.59 units on a scale |
p-value: <0.000195% CI: [2.76, 4.42]t-test, 2 sided
Primary
Function as Measured Subjectively by the Oswestry Disability Index Questionnaire
Oswestry Disability Index (ODI) measures permanent functional disability using questions regarding activities of daily living (ADL), specifically disturbance of ADL related to chronic back pain. Higher scores indicate a 'more limited' life. The ten topics of the ODI are rated from zero (no pain/limitation) to five (high pain/very limited physically). The worst possible score is 50 (100% disability) with the best score being zero (0% disability).Change from baseline to 6 months is presented below, where a positive value represents the baseline value minus the 6 month value.
Time frame: Baseline and Month 6
Population: All available patients at 6 months are reported below.
| Arm | Measure | Value (MEAN) |
|---|---|---|
| Lumbar Decompression | Function as Measured Subjectively by the Oswestry Disability Index Questionnaire | 12.17 units on a scale |
p-value: <0.000195% CI: [6.64, 17.71]t-test, 2 sided
Primary
Quality of Life Changes as Determined by Short Form 12-question (SF-12) Survey Specifically Related to Physical Component Score (PCS).
The SF-12 is a validated norm-based scoring tool used to determine treatment outcomes. The PCS summary measure shows the impact of the treatment on the patients abilities to conduct their usual physical activities. Clinical relevance of PCS is established by baseline to post-treatment improvement of 2 to 3 points. Norm-based scoring is used so that each scale has the same mean (50 points) and the same standard deviation (10 points) as the general US population in 1998. Scores below 50 indicate a decline in health status, with lower scores representing worse health status. Minimally Important Difference (MID) is a measure of true clinical relevance of a difference, with suggested MID for the Physical Component Summary (PCS) being 2 to 3 points. Change from baseline to 6 months is presented, where a positive value represents the 6 month value minus the baseline value.
Time frame: Baseline and Month 6
Population: All participants at month 6 who completed all questionnaire fields necessary to analyze PCS data according to guidelines.
| Arm | Measure | Value (MEAN) |
|---|---|---|
| Lumbar Decompression | Quality of Life Changes as Determined by Short Form 12-question (SF-12) Survey Specifically Related to Physical Component Score (PCS). | 8.32 units on a scale |