Lumbar Fusion With Nexxt Spine 3D-Printed Titanium Interbody Cages

Study Overview
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Brief Summary
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The purpose of this randomized controlled trial is to assess and compare radiographic and clinical outcomes in patients who are to undergo combined interbody/posterolateral lumbar fusion procedures, supplemented with pedicle screw instrumentation, using one of the following interbody cages; the Nexxt Spine Nexxt MatrixxTM 3D-printed titanium cage or the HonourTM poly-ether-ether-ketone cage.

Detailed Description
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This randomized controlled trial will prospectively evaluate the safety and efficacy of the Nexxt MatrixxTM System titanium implant supplemented with a pedicle screw system as compared to a representative PEEK cage currently used in routine fashion for lumbar interbody fusion procedures. This study will capture clinical and radiographic outcomes on patients up to 2 years post operatively. Both cages will be used in conjunction with milled local autograft bone generated as part of the spinal fusion procedure (no iliac crest autograft will be utilized). This single centered study will enroll up to 70 subjects (n = 35 per group), with subjects followed for 24 months post-surgery. All subjects enrolled in the study will be recruited from a pool of subjects eligible for combined interbody/posterolateral lumbar fusion surgery. Subjects will be randomized in the trial to receive either the Nexxt Spine Nexxt MatrixxTM 3D-printed titanium cage or the HonourTM PEEK cage supplemented with a pedicle screw system and milled local autograft bone. Subject randomization will be stratified according to smoking status. Subjects will be blinded to their group status for the duration of the study assessments and procedures (24 months post-operatively). Subject study data will be collected preoperatively, intra-operatively and postoperatively at 3, 6, 12, and 24 months.

Official Title
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Lumbar Fusion With 3D-Printed Porous Titanium Interbody Cages - A Single-Blinded Randomized Controlled Trial Evaluating Nexxt Matrixx(TM) Versus PEEK Cages

Conditions
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Lumbar Degenerative Disc Disease, Lumbar Spinal Stenosis, Lumbar Spondylolisthesis, Lumbar Spinal Deformity, Lumbar Spondylosis

Intervention / Treatment
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* Device: Interbody cage (titanium)
* Device: Interbody cage (PEEK)


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Subject is scheduled to undergo combined interbody and posterolateral spinal fusion surgery using either the Nexxt MatrixxTM 3D-printed titanium cage or HonourTM PEEK cage in conjunction with local autograft bone, and supplementation with a pedicle screw system. Subject must be over the age of 18 years old. Subject has been unresponsive to conservative care for a minimum of 6 months. The subject must in the investigator's opinion, be psychosocially, mentally, and physically able to fully comply with this protocol including the required follow-up visits, the filling out of required forms, and have the ability to understand and give written informed consent. Exclusion Criteria: Subjects with previous lumbar arthrodesis surgery. Subjects requiring additional bone grafting materials other than local autograft bone. Subject has inadequate tissue coverage over the operative site. Subject has an open wound local to the operative area, or rapid joint disease, bone absorption, or osteoporosis. Subject has a condition requiring medications that may interfere with bone or soft tissue healing (i.e., oral or parenteral glucocorticoids, immunosuppressives, methotrexate, etc.). Subject has an active local or systemic infection. Subject has a metal sensitivity/foreign body sensitivity. Subject is morbidly obese, defined as a body mass index (BMI) greater than 40. Subject has any medical condition or extenuating circumstance that, in the opinion of the investigator, would preclude participation in the study. Subject is currently involved in another investigational drug or device study that could confound study data. Subject has a history (present or past) of substance abuse (recreational drugs, prescription drugs or alcohol) that in the investigator's opinion may interfere with protocol assessments and/or with the subject's ability to complete the protocol required follow-up. Subjects who are pregnant or plan to become pregnant in the next 12 months or who are lactating. Subject is involved in or planning to engage in litigation or receiving Worker's Compensation related to neck or back pain. Subject is a prisoner.

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
Interventional Model Description: All subjects will be randomized in the trial to receive either the Nexxt Spine Nexxt MatrixxTM 3D-printed titanium cage or the HonourTM PEEK cage supplemented with a pedicle screw system and milled local autograft bone. Subject randomization will be stratified according to smoking status.
Masking: Single


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Active Comparator: 3D-printed titanium cage<br>Subjects enrolled in this arm will have the Nexxt Spine Nexxt MatrixxTM 3D-printed titanium cage (interbody cage) implanted at each level of 1 or 2-level lumbar arthrodesis procedures. All constructs will be supplemented with a pedicle screw system (Depuy Synthes Expedium) cleared for lumbar spinal fusion. | Device: Interbody cage (titanium)<br>* Subject will be implanted with a 3D-printed titanium cage during their lumbar interbody fusion surgery.<br>|
| Active Comparator: Poly-ether-ether-ketone (PEEK) cage<br>Subjects enrolled in this arm will have the HonourTM poly-ether-ether-ketone (PEEK) cage (interbody cage) implanted at each level of 1 or 2-level lumbar arthrodesis procedures. All constructs will be supplemented with a pedicle screw system (Depuy Synthes Expedium) cleared for lumbar spinal fusion. | Device: Interbody cage (PEEK)<br>* Subject will be implanted with a poly-ether-ether-ketone (PEEK) cage during their lumbar interbody fusion surgery.<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Interbody Radiographic Fusion Rate | Interbody fusion will be graded using the Brantigan, Steffee, Fraser (BSF) Scale which classifies fusion between the interbody cage and adjacent bone on a scale of 1-3 where a higher score indicates a better outcome. The grades are defined as follows: Brantigan, Steffee, Fraser-Grade 1 (BSF-1) indicates radiographical pseudarthrosis, Brantigan, Steffee, Fraser-Grade 2 (BSF-2) is defined by radiographical locked pseudarthrosis, and Brantigan, Steffee, Fraser-Grade 3 (BSF-3) is radiographical fusion, indicating the best outcome. The subject will be considered a success if fusion is a Grade BSF-3 at 6 months. | 6 months post-operatively | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Post-operative Timing of Fusion | Secondary measures of effectiveness will be determined by timing of fusion observed in X-rays post-operatively. Fusion at one year was defined as a difference in cobb angle of the operated levels between flexion and extension views. More than 2 degrees of change between views indicated non-union at one year. | 12 months post-operatively | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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lumbar spinal arthrodesis, interbody cage, 3D-printing