In-house Produced PMMA- Versus PEEK-cages

Study Overview
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Brief Summary
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Subsidence of cervical cages is a common problem. For the study, a new polyacrylmethacrylate cage was designed and prospectively implanted in patients with a mono- or bilevel cervical pathology. As control, a commercially available PEEK-cage was used, patients were randomized using minimization randomization, controlling for age and bone mineral densitiy. The investigators hypothesize that the newly developed cage has similar clinical and radiological qualities compared to the PEEK-cage, but at a much more favourable cost-performance ratio.

Official Title
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Clinical Characterization of In-house Produced PMMA-cages in Patients With Cervical Pathology

Conditions
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Cervical Disc Degeneration, Cervical Stenosis

Intervention / Treatment
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* Device: Implantation of a PEEK-cage
* Device: PMMA-cage


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: virgin spines no emergency operation age above 18 sufficient knowledge of the German language indication for anterior cervical discectomy and fusion absence of concomitant spinal disease Exclusion Criteria: prior cervical surgery indications other than ACDF concomitant neoplastic, metabolic, severe general or infectious disease

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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Design Details

Primary Purpose: Treatment
Allocation: Randomized
Intervention Model: Parallel Assignment
Masking: None (Open Label)


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Active Comparator: PEEK-cage<br>Patients will receive a PEEK-cage | Device: Implantation of a PEEK-cage<br>* A commercially avaliable cuboid cervical cage will be implantet<br>|
| Experimental: PMMA-cage<br> | Device: PMMA-cage<br>* The in-house produced cervical cage will be implanted<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Clinical outcome (NDI) | NDI (Neck disability index) will be measured prior to surgery and 12 months after surgery. A difference of 20% between both groups is considered to be clinically significant, which is proposed for the experimental implant (PMMA-cage). | 12 months postoperative | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Clinical outcome (VAS-neck), Subsidence | VAS-neck will be measured prior to surgery and 12 months after surgery. A difference of 20% between both groups is considered to be clinically significant, which is proposed for the experimental implant (PMMA-cage). Cage Subsidence will be measured using lateral radiographs prior to surgery and 12 months after surgery. Due to an improved cage design, significantly less subsidence is proposed for the experimental implant (PMMA-cage). | 12 months postoperative |