Comparison of Software-assisted Implantation of Elastic Spine Pad (TM) With Respect to Postoperative Change in Neck Disability Index (NDI) With the Conventional Disc Spacer Squale (TM) After Anterior Cervical Discectomy for Cervical Disc Prolapse

Study Overview
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Brief Summary
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This is an investigator-initiated study. The primary goal is to evaluate the efficacy of two different cervical disc devices (prosthesis vs rigid spacer) with respect to postoperative change in neck disability index. The evaluation will include clinical and radiological parameters.

Conditions
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Intervertebral Disc Displacement

Intervention / Treatment
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* Device: Anterior cervical discectomy with prosthetic disc replacement / ESP.
* Device: Anterior cervical discectomy with prosthetic disc replacement / Squale.


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Indication for monosegmental anterior cervical discectomy with implantation of a disc prosthesis Exclusion Criteria: Radiologic signs of extensive bone degeneration in the affected segment Necessity of implantation of a device smaller in height than 5 mm (as predicted with teh use of the Vertaplan (TM) software Transversal spine cord lesion Cervical myelopathy Preceding surgery on the cervical spine Traumatic lesions of the cervical spine Radiographic instability in the affected segment: flexion / extension: shift sagittal plane> 3.5 mm or 20% and rotation in the sagittal plane > 20 °, OR in static X-ray examinations: shift in the sagittal plane 3.5 mm or 20% of the vertebral body width and relative sagittal plane angulation > 11º signs of instability (Olisthesis) in another segment of the cervical spine Active systemic infection diseases of the rheumatic type and all autoimmune diseases bone metabolic diseases (for example, Paget's disease) skeletal metastases infections in the cervical spine Neurological seizure disorders or other serious neurological disease with risk of falls Severe heart failure (NYHA III-IV) Bleeding disorders or clopidogrel / coumarins - treatment Systemic use of corticosteroids for more than a month in the last 12 months Pregnancy Legally incompetent patient Lactation Deformity, anomalies, not fully developed skeleton Local tumor disease Pre-existing neurologic abnormalities or other shortcomings, such as a Parkinson's disease, diabetic neuropathy, multiple sclerosis, peripheral neuropathy Drug / drug or alcohol dependence

Ages Eligible for Study
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Minimum Age: 18 Years
Maximum Age: 50 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 |
| --- | --- |
| Experimental: Elastic spine pad<br>Patients, who receive Elastic Spine Pad (TM) as cervical disc prosthesis after ventral discectomy. | Device: Anterior cervical discectomy with prosthetic disc replacement / ESP.<br>* Anterior cervical discectomy, with the use of the ESP prosthesis (Manufacturer: FH orthopedics, Mulhouse, France) for the disc replacement.<br>|
| Active Comparator: Squale<br>Patients, who receive Squale (TM) as cervical disc prosthesis after ventral discectomy. | Device: Anterior cervical discectomy with prosthetic disc replacement / Squale.<br>* Anterior cervical discectomy, with the use of the Squale spacer (Manufacturer: OSD, Avignon, France) for the disc replacement.<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Change in Neck disability index compared to baseline |  | 6 weeks, 3, 6, 12 and 24 months postoperative | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Change in visual analogue scale for pain in the neck and peripheral pain compared to baseline |  | 6 weeks, 3, 6, 12 and 24 months postoperative | 
| Change in EuroQOL (EQ-5D) compared to baseline |  | 6 weeks, 3, 6, 12 and 24 months postoperative | 
| Change in Core Outcome Measure Index (COMI) compared to baseline |  | 6 weeks, 3, 6, 12 and 24 months postoperative | 
| Change in flexion and extension radiographs compared to baseline (angle difference [deg]). |  | 6 weeks, 3, 6 and 12 months postoperative | 
| Change in and computer aided measurement of segmental height degeneration in adjacent segments compared to baseline (distance difference [mm]) |  | 6 weeks, 3, 6 and 12 months postoperative | 
| Change in consumption of analgetics compared to baseline | The change in analgetics consumption will be assessed on a scale of increase - stable - reduction. | 6 weeks, 3, 6, 12 and 24 months postoperative | 
| Return to work |  | 6 weeks postoperative | 
| Return to work |  | 3 months postoperative | 
| Return to work |  | 6 months postoperative | 
| Return to work |  | 12 months postoperative | 
| Return to work |  | 24 months postoperative | 
| Mortality |  | 6 weeks postoperative | 
| Mortality |  | 3 months postoperative | 
| Mortality |  | 6 months postoperative | 
| Mortality |  | 12 months postoperative | 
| Mortality |  | 24 months postoperative | 
| Adverse effects |  | 6 weeks postoperative | 
| Adverse effects |  | 3 months postoperative | 
| Adverse effects |  | 6 months postoperative | 
| Adverse effects |  | 12 months postoperative | 
| Adverse effects |  | 24 months postoperative |