Lumbar Spinal Stenosis
Conditions
Brief summary
This is a single-center study evaluating the outcomes of patients with painful lumbar spinal stenosis who were treated with the mild procedure (minimally invasive lumbar decompression. The patients will be followed for 6 months after the procedure.
Detailed description
Approximately 50 patients at a single center will be enrolled and followed for a period of up to 26 weeks. Adult patients with symptomatic lumbar spinal stenosis who meet the enrollment criteria will be offered the mild procedure as an alternative to surgery or continued standard non-surgical medical management.
Interventions
PROCEDUREMinimally Invasive Lumbar Decompression
This minimally invasive procedure is performed under fluoroscopic image guidance through a dorsal approach to the spine. The patient is given local anesthesia and a sedative but needs to be responsive to the surgeon's questions for neurological monitoring. Under image guidance, the mild tools are inserted and positioned on the posterior spinal lamina, to the left or right of the spinous process. The tools are used to cut and remove tissue and bone from the posterior side of the lumbar spine to create a space inside the spine that can help decompress some of the spinal nerves.
Sponsors
Vertos Medical, Inc.
The Center for Pain Relief, 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
Yes
Inclusion criteria
* Symptomatic and lumbar spinal stenosis caused by dorsal element hypertrophy * Prior failure of conservative therapy and Oswestry Disability Index (ODI) \>20% * Radiologic evidence of lumbar spinal stenosis, ligamentum flavum hypertrophy (typically \>2.5mm),confirmed by pre-op MRI/CT report * Central canal cross sectional area clearly reduced per MRI/CT report * If present, anterior listhesis \< or = to 5.0mm (preferred) and deemed stable by the Investigator * Able to walk at least 10 feet unaided before being limited by pain * Available to complete 26 weeks of follow up * A signed Consent Form is obtained from the patient * Adults 18 years of age or older
Exclusion criteria
* Prior surgery at the intended treatment level * Compound fracture with intraspinal retropulsion contributing to spinal stenosis * Disabling back or leg pain from causes other than lumbar spinal stenosis * 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 steroids with 3 weeks prior to procedure * Inability of patient to lie prone for any reason with anesthesia support * Metabolic wound healing pathologies that may be deemed by the Investigator to compromise the 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 |
|---|---|---|
| Pain as Measured by Visual Analog Scale (VAS). | Baseline and six months | A validated ten point scale was used where ten is the worst possible pain and zero represents complete lack of pain. The change from baseline to six months is presented below, where a positive value represents the baseline value minus the 6 month value. |
Secondary
| Measure | Time frame | Description |
|---|---|---|
| Improvement in Functional Mobility | baseline and month 6 | Measured subjectively by the Oswestry Disability Index. Extent of disturbance in activities of daily living is subjectively reported using this validated instrument.Higher score indicate greater limitations in activity. The questionnaire is divided into 10 topics including pain intensity, personal care, lifting walking standing sitting, sleeping social life, traveling, employment/homemaking. Each topic is rated zero (no pain or no limitation) to 5 (high pain or very limited physically) based on typical pain and/or physical limitations. The worst possible score is 50 (100% disability) and the best score is zero (0% disability).Change from baseline to month 6 is reported below, where a positive value represents the baseline value minus the month 6 value. |
| Quality of Life as Measured by the Symptom Severity Scale of the Zurich Claudication Questionnaire (ZCQ). | Baseline and month 6 | As a validated patient outcome tool specific to lumbar spinal stenosis, Zurich Claudication Questionnaire (ZCQ) captures symptom severity as a quality of life indicator. A mean score of 1 is the best possible outcome representing 'no pain' in symptom severity, whereas higher mean scores up to a maximum of 5 indicate worse patient symptoms. The symptom severity outcomes are presented below as change from baseline to month 6 where a positive value represents the baseline value minus the 6 month value. Treatment is considered 'successful' or 'clinically relevant' if the patient population has at least a 0.5 improvement in symptom severity. |
| Quality of Life as Measured by Physical Function Scale of the Zurich Claudication Questionnaire (ZCQ). | Baseline and month 6 | For this ZCQ domain, a mean score of 1 is the best possible outcome representing 'no limitation' in physical function, whereas a mean score of 4 indicates worst physical function. Zurich Claudication physical function scale from this validated lumbar spine-specific measurement questionnaire are reported below as change from baseline to month 6. A positive value represents the baseline value minus the 6 month value. Treatment is considered clinically relevant when at least a 0.5 improvement is achieved. |
Countries
United States
Participant flow
Recruitment details
Patients were enrolled through one site (Center for Pain Relief) between March 2010 to January 2011.
Participants by arm
| Arm | Count |
|---|---|
| Minimally Invasive Lumbar Decompression Lumbar spinal stenosis patients exhibiting neurogenic claudication with predominance of ligamentum flavum hypertrophy were treated percutaneously using the mild Device Kit to decompress the target area. | 46 |
| Total | 46 |
Baseline characteristics
| Characteristic | Minimally Invasive Lumbar Decompression |
|---|---|
| Age, Categorical <=18 years | 0 Participants |
| Age, Categorical >=65 years | 27 Participants |
| Age, Categorical Between 18 and 65 years | 19 Participants |
| Age Continuous | 66.1 years STANDARD_DEVIATION 8.7 |
| Region of Enrollment United States | 46 participants |
| Sex: Female, Male Female | 29 Participants |
| Sex: Female, Male Male | 17 Participants |
Adverse events
| Event type | EG000 affected / at risk |
|---|---|
| deaths Total, all-cause mortality | — / — |
| other Total, other adverse events | 0 / 46 |
| serious Total, serious adverse events | 0 / 46 |
Outcome results
Primary
Pain as Measured by Visual Analog Scale (VAS).
A validated ten point scale was used where ten is the worst possible pain and zero represents complete lack of pain. The change from baseline to six months is presented below, where a positive value represents the baseline value minus the 6 month value.
Time frame: Baseline and six months
Population: all available patients reporting at Month 6
| Arm | Measure | Value (MEAN) |
|---|---|---|
| Minimally Invasive Lumbar Decompression | Pain as Measured by Visual Analog Scale (VAS). | 2.17 units on a scale |
p-value: <0.000195% CI: [1.17, 3.16]t-test, 2 sided
Secondary
Improvement in Functional Mobility
Measured subjectively by the Oswestry Disability Index. Extent of disturbance in activities of daily living is subjectively reported using this validated instrument.Higher score indicate greater limitations in activity. The questionnaire is divided into 10 topics including pain intensity, personal care, lifting walking standing sitting, sleeping social life, traveling, employment/homemaking. Each topic is rated zero (no pain or no limitation) to 5 (high pain or very limited physically) based on typical pain and/or physical limitations. The worst possible score is 50 (100% disability) and the best score is zero (0% disability).Change from baseline to month 6 is reported below, where a positive value represents the baseline value minus the month 6 value.
Time frame: baseline and month 6
Population: All available patients at six months were analyzed.
| Arm | Measure | Value (MEAN) |
|---|---|---|
| Minimally Invasive Lumbar Decompression | Improvement in Functional Mobility | 13.43 units on a scale |
p-value: <0.000195% CI: [8.42, 18.43]t-test, 2 sided
Secondary
Quality of Life as Measured by Physical Function Scale of the Zurich Claudication Questionnaire (ZCQ).
For this ZCQ domain, a mean score of 1 is the best possible outcome representing 'no limitation' in physical function, whereas a mean score of 4 indicates worst physical function. Zurich Claudication physical function scale from this validated lumbar spine-specific measurement questionnaire are reported below as change from baseline to month 6. A positive value represents the baseline value minus the 6 month value. Treatment is considered clinically relevant when at least a 0.5 improvement is achieved.
Time frame: Baseline and month 6
Population: All available patients at the month 6 reporting period were analyzed.
| Arm | Measure | Value (MEAN) |
|---|---|---|
| Minimally Invasive Lumbar Decompression | Quality of Life as Measured by Physical Function Scale of the Zurich Claudication Questionnaire (ZCQ). | 0.59 units on a scale |
Secondary
Quality of Life as Measured by the Symptom Severity Scale of the Zurich Claudication Questionnaire (ZCQ).
As a validated patient outcome tool specific to lumbar spinal stenosis, Zurich Claudication Questionnaire (ZCQ) captures symptom severity as a quality of life indicator. A mean score of 1 is the best possible outcome representing 'no pain' in symptom severity, whereas higher mean scores up to a maximum of 5 indicate worse patient symptoms. The symptom severity outcomes are presented below as change from baseline to month 6 where a positive value represents the baseline value minus the 6 month value. Treatment is considered 'successful' or 'clinically relevant' if the patient population has at least a 0.5 improvement in symptom severity.
Time frame: Baseline and month 6
Population: All patients having a month six report report were analyzed.
| Arm | Measure | Value (MEAN) |
|---|---|---|
| Minimally Invasive Lumbar Decompression | Quality of Life as Measured by the Symptom Severity Scale of the Zurich Claudication Questionnaire (ZCQ). | 1.07 units on a scale |