Post-Market, Long-Term Follow Up of Mobi-C® Cervical Disc for One and Two Level Treatment of Cervical Disc Disease

Study Overview
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Brief Summary
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The purpose of this study is to evaluate clinical and patient-reported outcomes at 10 years following surgery for a cohort of Mobi-C subjects treated on the IDE/Post Approval studies

Detailed Description
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This is a prospective, multi-center, consecutive cohort study. Subjects invited to participate in this study will have completed the Mobi-C IDE study (G050212). In this study, five hundred and seventy-five subjects were randomized to either the Mobi-C prosthesis or the control treatment - conventional anterior cervical discectomy and fusion (ACDF) with anterior cervical plating. The study was randomized in a 2 to 1 ratio (two Mobi-C subjects for every one subject receiving ACDF with anterior cervical plate). The subject retention rate for Mobi-C subjects was 80.1% (1 level)-84.4% (2 level) at 7 years. As non-inferiority (1-level) and superiority (2-level) have been well established through 7 years, the design of this study will focus on the long-term outcomes of a cohort of the Mobi-C arm of the study and evaluate the durability of outcomes at 10 years. Study sites invited to participate will be those that enrolled at least 10 subjects, and also had the highest retention rates at 7 years (≥70%). All subjects at these sites will be contacted to participate in an additional 10 year follow up visit. It is estimated that up to 250 subjects will be enrolled at 9-12 study sites. Certain endpoints are better assessed in comparison to the control ACDF arm, such as adjacent segment degeneration and subsequent surgery. This study has been amended to include a subset of sites that will also enroll control subjects. Up to 3 sites and 50 subjects will be included in this control cohort.

Official Title
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Post-Market, Long-Term Follow Up of Mobi-C® Cervical Disc for One and Two Level Treatment of Cervical Disc Disease

Conditions
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Cervical Disc Disease, Cervical Disc Degeneration

Intervention / Treatment
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* Device: Mobi-C


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Prior enrollment in LDR-001 Pivotal Study (IDE G050212); Written informed consent provided by subject or subject's legally authorized representative Exclusion Criteria: Documented withdrawal of consent from prior Mobi-C study; Documented non-compliance (including unwillingness to return to the site for follow-up visits) Reported pregnancy at time of enrollment, or with plans to become pregnant prior to completing study X-Rays

Ages Eligible for Study
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Minimum Age: 18 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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No

Study Plan
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How is the study designed?
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Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Mobi-C<br>Prior recipient of Mobi-C Disc in IDE/Post Approval Study | Device: Mobi-C<br>* Device for cervical intervertebral disc replacement at one or two contiguous levels<br>* Other names: Mobi-C Cervical Disc Prosthesis;|
| ACDF<br>Prior control subject in IDE/Post Approval Study | |

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| NDI Score |  | 10 Years | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Overall Success | Composite score composed of: 1) NDI improvement of at least 15 points (out of 50) from baseline; 2) No subsequent surgical intervention at the index level or levels; 3) No potentially (possibly or probably) device-related adverse event; 4) Maintenance or improvement in all components of neurologic status; and 5) No Mobi-C intraoperative changes in treatment. | 10 Year | 
| Neck Pain/Arm Pain VAS |  | 10 Year | 
| QOL SF-12 |  | 10 Year | 
| Patient Satisfaction | Measured by a two questions scale that includes ranking of level of satisfaction and willingness to recommend treatment. | 10 Year | 
| Secondary surgery Rate |  | 10 Years | 
| Device related complications |  | 10 Years | 
| Device displacement or migration | Radiographic assessment of movement of device from original placement | 10 Year | 
| Range of motion | Radiographically measured angle, in degrees, between endplates of adjacent vertebrae | 10 Years | 
| Disc Height | Radiographically measured distance, in mm, from corner of superior vertebra to corresponding corner of inferior vertebra | 10 Years | 
| Heterotopic Ossification | Qualitative radiographic assessment using McAfee grading system, grades 1-4 | 10 Years | 
| Adjacent Segment Degeneration | Qualitative radiographic assessment using Kellgren-Lawrence Disc Degeneration Grading, grades 0-IV | 10 Years |