Is Instrumentation Necessary for Static Degenerative Spondylolisthesis

Study Overview
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Brief Summary
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The purpose of this study is to determine whether instrumented lumbar fusion provides superior clinical outcomes in comparison to non-instrumented fusion in patients with static degenerative spondylolisthesis.

Detailed Description
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This study will determine whether instrumented lumbar fusion will provide superior clinical outcomes in comparison to non-instrumented fusion in patients with STATIC degenerative spondylolisthesis. At the time of scheduling surgery, patients who meet the inclusion/exclusion criteria will be asked to participate. Patients who agree, will be randomized to either non-instrumented or instrumented arthrodesis group. Intra-operative, peri-operative, and post-operative data will be collected and compared. The investigators predict to get very similar clinical outcomes between the two groups, with possibly less complications from the non-instrumented group and definitely a reduction in cost compared to the instrumented group.

Official Title
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Is Instrumentation Necessary for Static Degenerative Spondylolisthesis - A Prospective Randomized Clinical Study

Conditions
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Degenerative Spondylolisthesis, Spinal Stenosis

Intervention / Treatment
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* Procedure: instrumented spinal fusion with laminectomy
* Procedure: non-instrumented spinal fusion with laminectomy


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Patients with stable L4-5 spondylolisthesis on lumbar flexion and extension radiographs. Stability will be determined by the treating physician. Patients with concomitant spinal stenosis. Laminectomy at any lumbar levels of stenosis. Fusion only at L4-5 level. Exclusion Criteria: Prior lumbar spine surgery Multi-level spondylolisthesis Anterior interbody work/fusion Tumor Infection Trauma

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: Crossover Assignment
Masking: None (Open Label)


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Active Comparator: instrumented arthrodesis<br>Degenerative Spondylolisthesis and Spinal Stenosis patients having a surgical procedure. The surgical procedure is the intervention and is a spinal fusion with use of instrumentation and lumbar laminectomy. No additional drug or device intervention. | Procedure: instrumented spinal fusion with laminectomy<br>* Once determined that a patient has single level static degenerative spondylolisthesis and is planning to schedule surgery the patient will be approached by a research team member explaining the study and reviewing the informed consent document. If the patient chooses to participate, he or she will be randomized to be apart of the non-instrumented arthrodesis with laminectomy group or the instrumented arthrodesis with laminectomy group. Both are standard approved surgical approaches; however, using instrumentation is the more commonly used approach.<br>|
| Active Comparator: non-instrumented arthrodesis<br>Degenerative Spondylolisthesis and Spinal Stenosis patients having a surgical procedure. The surgical procedure is the intervention and is a spinal fusion without the use of instrumentation and lumbar laminectomy. No additional drug or device intervention. | Procedure: non-instrumented spinal fusion with laminectomy<br>* Once determined that a patient has single level static degenerative spondylolisthesis and is planning to schedule surgery the patient will be approached by a research team member explaining the study and reviewing the informed consent document. If the patient chooses to participate, he or she will be randomized to be apart of the non-instrumented arthrodesis with laminectomy group or the instrumented arthrodesis with laminectomy group. Both are standard approved surgical approaches; however, using instrumentation is the more commonly used approach.<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Functional Outcome Scores: SF-12/SF-36 Quality of Life Questionnaires | Measured by patient outcome survey such as the SF-12 or SF-36 Questionnaire (all questions are scored on a scale from 0 to 100, with 100 representing the highest level of functioning possible) | Up to 2 years | 
| Functional Outcome Scores: Oswestry Disability Index (ODI) Questionnaire | Measured by patient outcome survey such as the Oswestry Disability Index (ODI) that assesses low back pain (scoring ranges from 0 to >35) | Up to 2 years | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Rate of Infection | Wound Complications | Expected average of 4 weeks | 
| Rate of Symptomatic Pseudoarthrosis |  | Up to 2 years | 
| Need for Revision Surgery | Return to the OR | Up to 2 years | 
| Length of Hospital Stay |  | Expected average of 1 week | 
| Surgical Time |  | 2-4 hours |