Clinical and Radiological Outcomes of Oblique Lateral Lumbar Interbody Fusion

Study Overview
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Brief Summary
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This study is undertaken to evaluate the outcomes of Oblique Lateral Lumbar Interbody Fusion (OLLIF). Specifically, the study seeks to measure outcomes on radiological imaging, outcomes reported by the patients on standardized questionnaires, and complication rates.

Official Title
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Clinical and Radiological Outcomes of Oblique Lateral Lumbar Interbody Fusion

Conditions
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Degenerative Disc Disease, Spondylolisthesis, Lumbar Disc Herniation

Intervention / Treatment
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* Procedure: Oblique Lateral Lumbar Fusion


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Clinical diagnosis, confirmed by imaging, of one of the following conditions: severe degenerative disc disease, spondylolisthesis, spinal stenosis, disc herniation Completion of a full course of conservative therapy. Conservative therapy may include physical therapy, therapeutic injections, bracing and behavioral modification. Exclusion Criteria: bony obstruction of the approach significant spinal canal stenosis large facet hypertrophy grade II listhesis scoliosis with Cobb angle > 10º Patients who underwent procedures that were converted to open fusions
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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Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| OLLIF<br>Patients who underwent Oblique Lateral Lumbar Interbody Fusion | Procedure: Oblique Lateral Lumbar Fusion<br>* Oblique lateral lumbar interbody fusion (OLLIF) is a lumbar spinal fusion. OLLIF is performed with the patient in the prone position and employs an oblique lateral approach that enables the instrumentation to pass through Kambin's triangle which is defined as the space between the exiting nerve, the superior border of the caudal vertebra, and the superior articulating process of the inferior facet. This approach may be performed without direct visualization, guided by electrophysiological monitoring and biplanar fluoroscopy. During the approach, a blunt probe is used to make contact with the disc, followed by a series of gentle dilations. Discectomy is performed through a 10-mm access portal. The cage is inserted under continued electrophysiological monitoring and fluoroscopy.<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Patient reported disability on the Oswestry Disability Index | The Oswestry Disability Index is a commonly used tool to assess disability due to low back pain. The Oswestry is assessed on a standardized questionnaire and the scale ranges from 0% to 100% disability. A lower score is considered less disability. | One year after surgery | 
| Fusion rate | The rate of bony fusion as determined by independent radiologists on post-operative CT scans. Radiologists will determine whether each level that was operated on was fused, or not fused. | One year after surgery | 
| Rate of Neuropraxia | Neuropraxia is defined as lower extremity weakness of 3/5 or below on a standard 5 point strength scale as assessed by the surgeon at one year follow-up. The scale ranges from 5 (full strength) to 0 (no muscle tone). The deficit must have newly appeared just after surgery to be considered a result of the surgery. | One year after surgery | 
| Rate of Nerve Root Irritation | Nerve Root Irritation is defined as lower extremity paresthesias or dysesthesias corresponding to dermatome of the level of surgery or weakness of 4/5 or above on a standard 5 point strength scale as assessed by the surgeon at one year follow-up. The scale ranges from 5 (full strength) to 0 (no muscle tone). The deficit must have newly appeared just after surgery to be considered a result of the surgery. | One year after surgery | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Surgery Time | Skin to skin surgery time measured in minutes | During surgery | 
| Hospital stay | The number of nights spent in the hospital following the surgery measured in days | Immediately after surgery | 
| Blood Loss | The amount of blood lost during the surgery measured in milliliters. | During surgery | 
| Fluoroscopy Time | The time fluoroscopy was used during surgery measured in seconds. | During surgery. | 
| Rate of screw fracture | The percentage of all screws placed in the study group that is determined to have fractured on postoperative imaging. Imaging is read by independent radiologists. | One year after surgery | 
| Infection Rate | The percentage of patients that experienced a postoperative surgical site infection. | Immediately after surgery | 
| Bleeding Rate | The percentage of patients that experienced bleeding during surgery or immediately after surgery that required transfusion. | During surgery and immediately after surgery | 
| Patient reported pain on a 10-point pain scale | The level of pain reported by the patient on a standard 10-point pain scale. The scale goes from 0 (no pain) to 10 (worst pain imaginable) | One year after surgery | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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Degenerative Disk Disease, Lumbar Fusion, Minimally Invasive Surgery, Lumbar Disk Disease