VERTEBRAL LIGAMENT AMYLOID DEPOSITS IN SP INAL STENOSIS

Objective: We have searched for amyloid substance in 41 consecutive sa mples of tissue taken during laminectomies performed to relieve spinal canal stenoses. We also evaluated the relation between the occurrence of deposits and the age of patients. Methods: Tissue sections were st ained with Congo red; positive areas had to show green dichroism under polarized light. Results: Small amyloid deposits were found in fibrou s and fibro-elastic (ligamentum flavum) tissues in 14 subjects (34%). After age 60, the frequency was close to 50%. It reached 58% in those aged 70 or over. Our 3 patients aged 80 or more all had deposits. Ther e was also a relation between age and importance of the infiltration. Both sexes appeared evenly involved. Systemic amyloidosis (multiple my eloma) was demonstrated in a single patient. In this case infiltration was slightly more abundant and exceeded ligamentary structures, also involving vascular walls. Conclusions: Small amyloid deposits were fre quent in our material. Their presence and their abundance were closely related to the age of patients. Rarely, a more important infiltration , exceeding ligamentary structures will perhaps suggest a systemic for m of amyloidosis. A few other rare amyloid conditions (amyloidosis ass ociated with prolonged dialysis, amyloid tumour) have been reported to induce spinal canal stenosis. The occurrence of amyloid in vertebral ligaments of non-stenosed elderly persons is not documented; it may re present a new localization of senile amyloidosis.