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OsseoScrew Versus Fenestrated Pedicle Screws Augmented With Polymethylmethacrylate

Expandable Pedicle Screws Versus Fenestrated Pedicle Screws Augmented With Polymethylmethacrylate (PMMA): Complications and Clinical Outcomes in Patients With Osteoporosis or Poor Bone Quality

Status
Completed
Phases
Unknown
Study type
Observational
Source
ClinicalTrials.gov
Registry ID
NCT01613144
Acronym
EVOLVE
Enrollment
94
Registered
2012-06-07
Start date
2012-05-31
Completion date
2017-11-08
Last updated
2022-02-25

For informational purposes only — not medical advice. Sourced from public registries and may not reflect the latest updates. Terms

Conditions

Osteoporosis, Poor Bone Quality

Keywords

Osteopenia, Stenosis, Instability, Tumor

Brief summary

The purpose of this clinical investigation was to collect clinical evidence of the safety and efficacy of the OsseoScrew System. The OsseoScrew System is intended to provide immobilization and stabilization of spinal segments in skeletally mature patients as an adjunct to fusion. The study was designed to compare the safety and efficacy of OsseoScrew compared to any other commercially available fenestrated pedicle screw system augmented with PMMA for posterior spinal fixation after surgical correction of spinal deformity or pathology.

Detailed description

This was a randomized, open-label, controlled, multi-center study in which patients were randomized in a 1:1 ratio to receive either the OsseoScrew or any commercially available fenestrated screw augmented with polymethylmethacrylate (PMMA) (Control group) for posterior spinal fixation after surgical correction of spinal deformity or pathology. The study was planned to include up to 150 skeletally mature patients with spinal instability and osteopenia at up to 10 sites. Patients were to return postoperatively at 6 weeks (± 2 weeks) and at 6, 12, and 24 months (± 2 months) for assessments.

Interventions

DEVICEOsseoScrew Spinal Fixation System

Surgical intervention

Sponsors

Alphatec Spine, Inc.
Lead SponsorINDUSTRY

Study design

Observational model
COHORT
Time perspective
PROSPECTIVE

Eligibility

Sex/Gender
ALL
Age
18 Years to No maximum
Healthy volunteers
No

Inclusion criteria

1. ≥ 18 years of age 2. Spinal instability or deformity requiring fusion with instrumentation 3. Osteopenia defined as (T-Score of less than -1.0) 4. No response to nonoperative treatment modalities preceding enrollment. 5. Subject is willing and able to provide informed consent and agrees to release medical information for purposes of this study and to return for scheduled follow-up evaluations

Exclusion criteria

1. Active systemic or local infection 2. A life expectancy less than the study duration 3. Autoimmune disorders 4. Currently an alcohol, solvent, or drug abuser 5. Psychiatric or cognitive impairment that, in the opinion of the investigator, would interfere with the subject's ability to comply with the study requirements 6. History of allergies to any of the device components including but not limited to commercially pure titanium, titanium alloy, polymethylmethacrylate or Zirconium Oxide (ZrO2)

Design outcomes

Primary

MeasureTime frameDescription
Safety Endpoint: Rate of device-related or PMMA-related complications24 monthsThe proportion of patients who were free from device-related or PMMA-related complications leading to revision, supplemental fixation, non-elective removal, or reoperation throughout the study. Complications included, but were not limited to device or PMMA fracture, device or PMMA-related loosening, device or PMMA-related device disassembly, device migration or PMMA extravasation.
Efficacy Endpoint: Successful radiographic fusion24 monthsPresence of continuous bridging bone across the implant

Secondary

MeasureTime frameDescription
Oswestry Disability Index24 monthsThis is a measure of the patient's self reported permanent functional disability. Each section is scored on a 1-5 scale with 5 representing the greatest disability.
Visual Analogue Scale for back pain24 monthsThis is a measure of the characteristic or attitude that is believed to range across a continuum of values to measure pain intensity. The range of score is from 0 - 100. The patient marks on the line the point that they feel represents their perception of their current state. A higher score indicates greater pain intensity.
Adverse events24 monthsAdverse event rates

Countries

Belgium, Germany, Italy, Spain, United Kingdom

Outcome results

None listed

Source: ClinicalTrials.gov · Data processed: Feb 4, 2026