Screening for Systemic Amyloidosis Via the Ligamentum Flavum

Study Overview
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Brief Summary
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The investigators will prospectively evaluate for the presence of amyloid deposits in ligamentum flavum (yellow ligament) tissue samples obtained from patients undergoing spinal stenosis surgery. Patients who have tissue that stains positive for amyloid will be referred to an amyloidosis specialist.

Detailed Description
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Similar to carpal tunnel syndrome, spinal stenosis is associated with systemic amyloidosis and presents earlier than cardiac amyloidosis symptoms - 21-45% of ATTR patients and case reports in AL patients. The investigators' recent study found that 10% of older patients undergoing carpal tunnel release surgery were positive for amyloidosis, with 20% of that group presenting with cardiac involvement. 70% of the amyloid-positive group had a history of spinal stenosis and 40% required surgical intervention. Surgical intervention for spinal stenosis could provide an opportunity to screen for amyloidosis through yellow ligament (ligamentum flavum) biopsy. This study will look at the prevalence of amyloidosis in patients undergoing surgical intervention for non-congenital spinal stenosis and spondyloarthropathy. The investigators hypothesize that 10% of such patients will be positive for amyloidosis.

Official Title
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Screening for Systemic Amyloidosis Via the Ligamentum Flavum

Conditions
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Amyloid, Amyloidosis, Spinal Stenosis, Transthyretin Amyloidosis, Primary Amyloidosis of Light Chain Type

Intervention / Treatment
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* Procedure: Biopsy


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Age ≥50 years Undergoing surgical intervention for non-congenital spinal stenosis and/or spondyloarthropathy Able to consent Exclusion Criteria: History of congenital spinal stenosis or congenital spondyloarthropathy

Ages Eligible for Study
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Minimum Age: 50 Years

Sexes Eligible for Study
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All

Study Plan
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How is the study designed?
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Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Spinal Stenosis Biopsy<br>Biopsy of ligamentum flavum tissue during spinal stenosis surgery sent to pathology for amyloid-specific analysis | Procedure: Biopsy<br>* During clinically-scheduled spinal stenosis surgery, ligamentum flavum tissue (which may contain surrounding tissue and subcutaneous fat) that is removed during the procedure will be sent to pathology to be analyzed with amyloid-specific staining.<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Incidence of amyloidosis in older patients undergoing spinal stenosis surgery | Incidence of amyloid deposits in removed ligamentum flavum tissue of older patients undergoing spinal stenosis surgery | Baseline to 30 days | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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Biopsy, Surgery, Screening