Percutaneous Dynamic Stabilization (PDS) System Versus Fusion for Treating Degenerative Disc Disease

Interventional Spine

Status and phase: Terminated; Phase 2

Conditions: Lumbar Degenerative Disc Disease

Treatments: Device: Fusion; Device: PDS System

Study type: Interventional

Funder types: Industry

Identifiers

NCT00878579

PDS-002-DDD

Details and patient eligibility

About

The objective of this study is to evaluate the safety and effectiveness of the PDS System compared to the surgical control of posterolateral fusion with autograft and pedicle screw fixation for the treatment of one or two levels from L3-S1 to relieve back pain associated with degenerative disc disease.

Enrollment: 20 patients

Sex: All

Ages: 18 to 70 years old

Volunteers: No Healthy Volunteers

Inclusion criteria

1. Confirmation of DDD (back pain with degeneration of the disc by patient history, physical exam, and radiographic studies and with one or more of the following factors:

   • Osteophyte formation of facet joints or vertebral endplates
   • Facet joint degeneration (no more than mild to moderate)
   • Subjects with ≤50% collapse of disc as compared to the adjacent level
   • Subjects with or without a contained herniated nucleus pulposus <5 mm and no free fragment

2. Skeletally mature subjects aged between 18 and 70 years of age inclusive.

3. Subjects with primarily back pain associated with degenerative disc disease of the lumbar spine at one level or two adjacent levels from L3 through S1. Subjects may have a lesser degree of leg pain at the same level(s).

4. Subjects who require surgical or minimally invasive intervention, who have failed to adequately improve following 6 months of non-operative therapy.

5. Subject is a surgical candidate for a posterior approach to the lumbar spine and is suitable for fusion using pedicle screw systems

6. Subjects with a minimum baseline Oswestry Score of 40% (20/50).

7. Subjects with a minimum baseline VAS Score of 40/100 mm.

8. MRI diagnostic for DDD within 3 months of the screening visit.

9. Subjects who are mentally, physically and psychosocially able to cooperate with the study procedures and return for all required follow-up visits.

10. Subjects who are able to understand this study and have given voluntary, written informed consent to participate in this study.

Exclusion criteria

1. Subjects who have leg pain greater than back pain.
2. Subjects with severe facet degeneration, radiographic findings of severe facet joint disease, degeneration or misshapen facet(s) or structural anomalies at the target level(s) that would preclude placement of the PDS device or pedicle screw systems.
3. Subjects who require a pedicle screw smaller than 4.5 mm.
4. Subjects with Modic 3 bone changes at the target level(s).
5. Spondylolisthesis > Grade 1 and/or spondylolysis at the target level(s).
6. Subjects with myelopathy or cauda equina syndrome, defined as neural compression causing neurogenic bowel (rectal incontinence) or bladder dysfunction (retention or incontinence).
7. Subjects with fixed motor deficit and/or peripheral neuropathy.
8. Subjects with prior discectomy at the target level(s).
9. Subjects with prior spine surgery, trauma, metastatic disease, or spinal deformity due to scoliosis (Cobb angle > 15 degrees) or kyphosis (> 11 degrees) at any lumbar level.
10. Subjects who have used any investigational drug or device within the past 30 days or have had an experimental spinal implant at any time.
11. Subjects with active local or systemic infection.
12. Subjects with osteoporosis. A screening questionnaire for osteoporosis, SCORE (Simple Calculated Osteoporosis Risk Estimation), will be used to screen subjects. If DEXA is required, exclusion will be defined as a DEXA bone density measured T scored < -1.0.
13. Subjects with metabolic bone disease (e.g. osteomalacia, Paget's disease).
14. Subjects with rheumatoid arthritis or other autoimmune spondyloarthropathies.
15. Subjects with a systemic disease that compromises life expectancy (e.g. HIV, AIDS, hepatitis) or are on immuno-suppressive agents.
16. Subjects who are taking any drug known to potentially interfere with bony/soft tissue healing, (e.g., steroids at any dose daily within the last 12 months).
17. Subjects with active malignancy: A subject with a history of any invasive malignancy (except non-melanoma skin cancer), unless s/he has been treated with curative intent and there have been no clinical signs or symptoms of malignancy for at least 5 years.
18. Subjects with a known allergy to titanium and/or polycarbonate urethane (PCU).
19. Subjects who have existing conditions or pending litigation claims that could compromise their participation, follow-up care, or treatment outcomes (e.g., drug or alcohol abuse).
20. Subjects with a BMI of ≥ 40 kg/m2 or weight > 275 pounds (125 kg).
21. Subjects who are pregnant or are planning a pregnancy during the study period.
22. Subjects who are prisoners.

Trial design

Primary purpose: Treatment

Allocation: Randomized

Interventional model: Parallel Assignment

Masking: None (Open label)

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20 participants in 2 patient groups

PDS System

Experimental group

Treatment:

Device: PDS System

Fusion

Active Comparator group

Treatment:

Device: Fusion