DIAM™ Spinal Stabilization System vs. Decompression, Formerly vs. Posterolateral Fusion

Phase 3

Terminated

Conditions: Degenerative Lumbar Spinal Stenosis

Interventions: Device: Fusion
Device: DIAM Spinal Stabilization
Procedure: Single-Level Posterior Decompression

Registration Number: NCT00627497

Lead Sponsor: Medtronic Spinal and Biologics

Brief Summary: The purpose of this clinical trial is to evaluate the safety and effectiveness of the DIAM Spinal Stabilization System as a method of treating patients with symptoms of degenerative lumbar spinal stenosis at a single level from L2 to L5.

Detailed Description: This pivotal clinical trial is being conducted to evaluate the DIAM Spinal Stabilization System for the treatment of single-level degenerative lumbar spinal stenosis from L2 to L5. The implant under investigation in this clinical trial is the DIAM Spinal Stabilization System. And following a decompression procedure, the device will be implanted using a posterior surgical approach. Patients in the control group will receive a lumbar decompression.

Recruitment & Eligibility

Status: TERMINATED

Sex: All

Target Recruitment: 32

Inclusion Criteria

Has a symptom complex consisting of back, buttock, or groin pain (excluding symptomatic coxarthrosis) with leg pain typical of intermittent neurogenic claudication, which is defined as leg(usually calf) discomfort, pain, numbness, paresthesias, weakness, or fatigue aggravated by standing or walking and is only relieved with resting in flexed lumbar spine position
Leg pain score ≥ 8 and back pain score ≥ 6 based on the Preop Back/ Leg Pain CRF.

Leg pain score must be ≥ back pain score

Narrowing of the lumbar spinal canal and/or intervertebral foramen at L2-L3, L3-L4, L4-L5 as indicated by MRI, with other MRI findings typical of spinal stenosis, such as trefoil canal shape; hypertrophy, thickening, buckling, or infolding of the ligamentum flavum; hypertrophied facet joints or facet joint capsule; annular bulging; or lateral (subarticular) stenosis.
Must sit for at least 30 min without severe pain
Must walk at least 100 ft unassisted
35 yrs of age, inclusive
Preoperative Oswestry score ≥ 40
Child-bearing potential, pt is not pregnant or nursing and agrees not to become pregnant during study period
Treated non-operatively for a pd of at least 6 mos
Willing and able to comply with study plan and able to understand and sign Pt ICF

Exclusion Criteria

Disease state which requires destabilizing decompression
Axial back pain with no pain in leg, buttock, or groin
Baseline strength grade of 0 (total paralysis), 1 (palpable or visible contraction), or 2 (active movement, gravity,eliminated) in any lower extremity motor group as noted on Neuro Status CRF
Segmental kyphosis >0° at indicated level
Cauda equina syndrome
Compression of nerve roots that causes neurogenic bowel, bladder dysfunction
Prior surgical procedure at involved or adjacent levels
Diagnosed with significant peripheral neuropathy
Significant vascular disease causing vascular claudication
Requires tx of spinal stenosis at more than 1 lumbar level
Significant lumbar instability, defined as > 3mm translation on flexion/extension radiographs
Has > 3mm fixed spondylolisthesis at affected level
BMI ≥ 40
Sustained vertebral or hip fracture within last year
Has the following (if "Yes" to any risk below, a lumbar spine DEXA Scan is required for eligibility)
1. Previous diagnosis of osteoporosis, osteopenia, or osteomalacia
2. Postmenopausal Non-Black female over age of 60 who weighs ≤ 140 lbs
3. Postmenopausal female who has sustained a non traumatic hip, spine or wrist fracture
4. Male over age of 60 who has sustained non-traumatic hip or spine fracture
If level of DEXA T-score is -1.0 or lower pt is excluded from study
Lumbar scoliosis with Cobb angle of > 15°
Documented allergy to silicone, polyethylene, titanium or latex
Overt or active bacterial infection, local, systemic, and/or potential for bacteremia
Alcohol and/or drug abuser
Received tx with investigational therapy (device and/or pharmaceutical) within 30 days prior to entering study or such tx is planned during the 24 mos following enrollment in study
Suppressed immune system or has taken steroids at any dose daily for more than 1 mon within the last yr
Presence of active malignancy or prior history of malignancy except for basal cell carcinoma of the skin
History of any endocrine or metabolic disorder known to affect osteogenesis
Chronic or acute renal and/or hepatic failure or prior history of renal and/or hepatic parenchymal disease
History of autoimmune disease
Disease which precludes accurate clinical evaluation of safety and effectiveness of txs in this study
Congenital or iatrogenic posterior element insufficiency
Moderate to advance spondylosis or pts who demonstrate advanced degenerative changes. Such advanced degenerative changes are characterized by 1 or combination of the following a Bridging osteophytes; b Reduction or absence of motion; c Collapse of the intervertebral disc space of > 50% of its normal ht
Mentally incompetent
Waddell Signs of Inorganic Behavior score of ≥ 3
Prisoner

Study & Design

Study Type: INTERVENTIONAL

Study Design: PARALLEL

Arm && Interventions

Group	Intervention	Description
Posterolateral Interbody Fusion	Fusion	-
DIAM Group2	DIAM Spinal Stabilization	-
Single-Level Posterior Decompression	Single-Level Posterior Decompression	-
DIAM Group1	DIAM Spinal Stabilization	-

Primary Outcome Measures

Name	Time	Method
Rate of Overall Success	24 months after operation	Rate of overall success is reported as the percentage of partipants who met all of the following criteria: 1. Pain/disability (ODI) success:(Success of ODI is defined as pain/disability improvement according to the definition: Pre-treatment Score - Post-treatment Score ≥ 15); 2. Neurological success (Neurological success is defined as maintenance or improvement in sections of motor, sensory, reflex, and straight leg raise for the time period evaluated); 3. No serious adverse event classified as "surgical treatment associated"; 4. No additional surgical procedure classified as "failure."

Secondary Outcome Measures

Name	Time	Method
Operative Time	at the time of operation
Success Rate of Oswestry Diability Index Scores	24 month after operation	Success rate of Oswestry Diability Index Scores is reported as the percentage of participants who met: Pre-treatment Score - Post-treatment Score ≥ 15.
Oswestry Disability Index (ODI) Score	24 month after operation	The self-administered Oswestry Disability Index (ODI) Questionnaire was used to assess patient pain and ability to function. The ODI scale ranges from 0-100. The best score is 0 (no disability) and worst is 100 (maximum disability).
Back Pain	24 month after operation	Numerical rating scales are used to evaluate back pain intensity and frequency. Patients will rate their pain intensity on a scale from 0-10, with a score of 0 representing "no pain" and a score of 10 representing "pain as bad as it could be." Similarly, patients will record their back pain frequency on a scale from 0-10, with a score of 0 being "pain none of the time" and a score of 10 being "pain all of the time." A patient's total pain score will be the sum of pain intensity and frequency scores (0 min, 20 max).
Leg Pain Success Rate	24 month after operation	Leg pain success rate is reported as the percentage of participants whose leg pain improvement met: (Pre Score - Post Score)/ Pre Score \> 20%.
Leg Pain	24 month after operation	Numerical rating scales are used to evaluate leg intensity and frequency. Patients will rate their pain intensity on a scale from 0-10, with a score of 0 representing "no pain" and a score of 10 representing "pain as bad as it could be." Similarly, patients will record their back pain frequency on a scale from 0-10, with a score of 0 being "pain none of the time" and a score of 10 being "pain all of the time." A patient's total pain score will be the sum of pain intensity and frequency scores (0 min, 20 max).
General Health Status (SF-36)	24 month after operation	The Medical Outcomes Study 36-Item Short Form Health Survey (SF-36) was used to assess general health status. The SF-36 results are summarized into two components, a physical component summary (PCS) and a mental component summary (MCS). The score for PCS and MCS is between 0 and 100, with higher scores denoting better quality of life.
Blood Loss	At the time of operation
Hospital Stay	At the time of discharge
Success Rate of Neurological Status	24 month after operation	Success rate of neurological status is reported as the percentage of participants who met neurological success defined as maintenance or improvement in all sections (motor, sensory, reflex, and straight leg raising) for the time period evaluated. In order for a section to be considered a success, each element in the section must remain the same or improve from the time of the preoperative evaluation to the time period evaluated.
Back Pain Success Rate	24 month after operation	Back pain success rate is reported as the percentage of participants whose back pain improvement met: (Pre Score - Post Score)/ Pre Score \> 20%.
Success Rate of SF-36 Health Survey	24 month after operation	Success rate of SF-36 Health Survey include two components: the success rate of a physical component summary (PCS) and the success rate of a mental component summary (MCS). The success rates of SF-36 PCS and MCS for DIAM Device vs. Single-Level Posterior Decompression were defined as: (Post Score - Pre Score) / Pre Score\>= 20%. The success rates of SF-36 PCS and MCS for DIAM vs. Posterolateral Interbody Fusion were defined as: Post Score - Pre Score \>= 0.