Atypical Presentation of a Sequestered Posterolateral Disc Fragment

Olaide Ajayi , Alireza Shoakazemi , R. Shane Tubbs , Marc Moisi , Steven Rostad , David W. Newell

Abstract

Sequestered disc fragments typically occur ventrally but can also migrate dorsally or intradurally. At times, atypical disc herniations can be misinterpreted on imaging as other lesions, such as neoplasms, hematomas, or abscesses. We present an uncommon case of a patient presenting with cauda equina syndrome secondary to an enhancing sequestered disc fragment mimicking a tumor.

Introduction

Sequestered intervertebral disc fragments have the potential to migrate both intradurally and extradurally within the spinal canal. There are no particular clinical features allowing for a clear differentiation between patients with atypical disc herniations and those with tumors [1]. Free disc fragments were previously only identified during surgery but are still frequently misinterpreted as neoplastic masses, even after the introduction of magnetic resonance imaging (MRI) [1-3]. This is because the imaging characteristics of sequestered disc fragments may mimic known characteristics of extramedullary (intra- and extradural) lesions, including neoplasms and other benign epidural lesions (such as synovial cysts, hematomas, and abscesses), further complicating preoperative diagnosis based on imaging findings [1, 3].

We present an uncommon case of a cauda equina syndrome secondary to a large extradural ring-enhancing sequestered disc fragment, mimicking a tumor.