Comparison of Complication Rates Between Lateral Approaches to the Lumbar Spine

Study Overview
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Brief Summary
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An evaluation of the incidence of complications resulting from far lateral spine surgery utilizing the K2M RAVINE® Lateral Access System (RAVINE) with ALEUTIAN® Lateral Interbody Spacer System versus literature reported results for the NuVasive XLIF® system (XLIF) in the treatment of degenerative disc disease (DDD) with up to Grade 1 spondylolisthesis.

Detailed Description
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An evaluation of the incidence of complications resulting from far lateral spine surgery utilizing the K2M RAVINE® Lateral Access System (RAVINE) with ALEUTIAN® Lateral Interbody Spacer System versus literature reported results for the NuVasive XLIF® system (XLIF) in the treatment of degenerative disc disease (DDD) with up to Grade 1 spondylolisthesis at L2-S1 requiring surgical intervention at one or two contiguous levels. Safety will be assessed by the following: 1.) Evaluation of all adverse events including device related, procedure related and additional serious adverse events; 2.) Additional surgical intervention at the operative site including the need for removals, revisions, re-operations or supplemental fixation required to modify the device; and 3.) The incidence and severity of any psoas muscle injury, genital femoral nerve injury and lumbar plexus injury will be determined for all patients. Supplemental fixation of any kind may be included as long as the procedure is completed via a minimally invasive approach.

Official Title
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A Comparison of Complication Rates Between Lateral Approaches to the Lumbar Spine: K2M RAVINE® Far Lateral System Versus NuVasive XLIF®

Conditions
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Degenerative Disc Disease, Grade 1 Spondylolisthesis

Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Diagnosis of DDD with up to Grade 1 spondylolisthesis, confirmed clinically and radiographically, requiring surgical intervention at one or two contiguous levels between L2-S1 Inadequate response to conservative medical care over a period of at least 6 months Willing and able to comply with the requirements of the protocol including follow-up requirements Willing and able to sign a study specific informed consent Skeletally mature and ≥ 18 years of age at the time of enrollment Exclusion Criteria: Previous anterior/posterior/lateral spine surgery at the index level Previous posterior/lateral spine surgery (e.g., posterior element decompression) that destabilizes the lumbar spine Active systemic infection or infection at the operative site Co-morbid medical conditions of the spine or upper/lower extremities that may affect the lumbar spine neurological and/or pain assessment Metabolic bone disease such as osteoporosis that contradicts spinal surgery History of an osteoporotic fracture History of an endocrine or metabolic disorder (e.g., Paget's disease) known to affect bone and mineral metabolism Taking medications that may interfere with bony/soft tissue healing including chronic steroid use Known allergy to titanium, cobalt chrome or PEEK Rheumatoid arthritis or other autoimmune disease or a systemic disorder such as HIV, active hepatitis B or C or fibromyalgia Current medical condition (e.g., unstable cardiac disease, cancer) that may result in patient death or have an effect on outcomes prior to study completion Pregnant, or intend to become pregnant, during the course of the study Severe obesity (Body Mass Index > 40) Physical or mental condition (e.g., psychiatric disorder, senile dementia, Alzheimer's disease, alcohol or drug addiction) that would interfere with patient self-assessment of function, pain or quality of life Involved in current or pending spinal litigation where permanent disability benefits are being sought Incarcerated at the time of study enrollment Current participation in an investigational study that may impact study outcomes

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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What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Visual Analog Scale (VAS) Change From Baseline | Evaluation of the change of the Back VAS, Hip VAS and the Leg VAS at the 24 month post-operative visit as compared to pre-op time periods. Information on all reports of pain/numbness/tingling and the location of symptoms were captured and evaluated. VAS scale ranged from 0 - 10cm with the 10cm accounting for the highest level of pain. | 24 months | 
| Number of Patients With Adverse Events AEs) | The evaluation of all adverse events including device related, procedure related and additional serious adverse events. | Operative to 24 month | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Change in Pain/Dysesthesia Score From Baseline (Pre-Operative) | Neurological evaluation of the patient, with specific evaluation of psoas muscle weakness, radiating radicular pain, knee extension weakness, dorsiflexion weakness, plantarflexion weakness and anterior thigh numbness was performed using Patient symptom Questionnaire (0-100mm analog scale with 100mm being the highest pain/weakness/numbness) | time of discharge, an average of 4.5 days, up to 8 weeks post-operatively, 3 months, 6 months, 12 months, 24 months | 
| Change in Oswestry Disability Index From Baseline (Pre-Operative) | The Oswestry Disability Index (ODI) is a validated instrument including items that relate to subjective symptomatology and activities of daily living (pain intensity, personal care, lifting, walking, sitting, standing, sex life, traveling). This patient-reported outcome measure is a 10 item questionnaire that evaluates disability and functional impairment associated with back problems. Each item is scored from O up to 5, with higher scores corresponding to greater disability. A total ODI score is determined by adding the scores of the individual questions and dividing that total by the maximum possible score (i.e., 50 if all questions are answered) to yield a percentage. Therefore, the ODI score ranges from 0% to 100%. | time of discharge, an average of 4.5 days, up to 8 weeks post-operatively, 3 months, 6 months, 12 months, 24 months | 
| Change in Health-Related Quality of Life From Baseline (Pre-op) | Health-related quality of life was evaluated in all study subjects using the SF-12v2 Health Survey. This shortened and simplified version of the SF-36 makes the questionnaire less ambiguous for patients. It has a self-administered form that makes it easy to read and complete, and that reduces missing responses. The physical and mental component summary scales, referred to as PCS-12 and MCS-12 were evaluated against published normative values and a 15% improvement in these scores was used as an assessment of success. In calculating the true value of a treatment, the scores from the SF-12v2 were converted into a utility index (SF-6D), which considered not only how many years a medical intervention could have added to a patient's life, but also the quality of that life. Use of the SF-6D did not expand the questions administered to the patients. The scale ranged from 0-100% with 100% being the best quality of life. | time of discharge, an average of 4.5 days, up to 8 weeks post-operatively, 3 months, 6 months, 12 months, 24 months | 
| Radiographic Assessments | Quantitative and qualitative radiographic assessment of the pre and post-operative AP, and Lateral, Flexion/Extension images were performed. Radiographic and qualitative assessments performed include: Device Condition: looks at both the cage inside the vertebrae and the hardware outside the vertebrae. It looks at whether or not the device is intact or not (subsidence or migration) Fusion/Non-fusion: whether bone has grown within the space between the spinal vertebrae. If fusion occurs, it results in Bony Bridging | 12 mo to 24 mo | 
| Patient Satisfaction | At the 12 month and 24 month follow-up visits, subjects were asked whether they were satisfied with the outcome of their surgery (Yes/No) and whether they would repeat the operation (Yes/No). | 12 month and 24 month | 
| Odom's Criteria | At the 24 month follow-up visit, the Investigator rated the clinical disposition of each study subject according to Odom's Criteria as follows: Excellent: all pre-operative symptoms relieved, able to carry out daily occupations without impairment. Good: minimum persistence of pre-operative symptoms, able to carry out daily occupations without significant interference. Fair/Satisfactory: relief of some pre-operative symptoms but physical activity is significantly limited. Poor: symptoms or signs unchanged or worse. | 24 months | 
| Surgery Time | The length of the surgical procedure from the initial incision to final closure were captured from the Anesthesia Record. | During operation. | 
| Anesthesia Time | The length of time the patient is under anesthesia were captured from the Anesthesia Record. | During operation. | 
| Estimated Blood Loss | The amount of blood loss over the entire length of the surgery, documented on the Anesthesia Record, was captured. | During Operation | 
| Number of Participants With Abnormal Neuromonitoring System Results | Abnormal result(s) of neuromonitoring systems (Train of Four, Electromyography (EMG), Triggered EMG, Somato Sensory Evoked Potential (SSEP) and Motor Evoked Potential (MEP)) utilized during the surgery were captured. | During operation | 
| Length of Hospital Stay | The length of hospital stay from the date of hospital admission to the date of discharge was calculated. | From admission to discharge | 
| Change in Work/School Status Compared to Baseline | The ability to and the time it takes for the subject to be cleared to return to work/school from the date of surgery was documented. | Pre-operative to 24 months | 
| Change in Use of Narcotics Post-Surgery Compared to Baseline | The types and dosages of any narcotics taken by the patient post-surgery were documented. | Pre-operative to 24 months | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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degenerative disc disease, DDD, Grade 1 spondylolisthesis, spondylolisthesis, L2-S1