title: Discography aids definitive diagnosis of posterior epidural migration of lumbar disc fragments: case report and literature review.
abstract: Posterior epidural migration of lumbar disc fragments (PEMLDF) is extremely rare. It is often confused with other posterior lesions and is usually diagnosed intraoperatively. We here describe the use of preoperative discography in the diagnosis of PEMLDF.
  
  
  
  A 78-year-old man presented with acute low back pain, gait disturbance, and paresthesia in both legs. Magnetic resonance imaging showed a mass located posteriorly and laterally to the left aspect of the dural sac at the L3 level. The initial diagnosis indicated PEMLDF, malignancy, spontaneous hematoma, or epidural abscess. L3/4 discography clearly showed leakage of the contrast medium into the posterior dural space, indicating PEMLDF. The lesion was identified intraoperatively as a herniated-disc fragment, consistent with the preoperative discography.
  
  
  
  PEMDLF is difficult to diagnose preoperatively. Discography is useful for the definitive diagnosis of PEMDLF prior to surgery.
authors.affiliation: Department of Orthopaedic Surgery, Spine Center, Kitasato Institute Hospital, 5-9-1 Shirokane, Minato-ku, Tokyo, 108-8642, Japan. moritto@me.com.|Department of Orthopaedic Surgery, Keiyu Hospital, 3-7-3 Minatomirai, Nishi-ku, Yokohama, Kanagawa, 220-8521, Japan. moritto@me.com.
authors.forename: Morito
authors.initials: M
authors.lastname: Takano
authors.affiliation: Department of Orthopaedic Surgery, Spine Center, Kitasato Institute Hospital, 5-9-1 Shirokane, Minato-ku, Tokyo, 108-8642, Japan.
authors.forename: Tomohiro
authors.initials: T
authors.lastname: Hikata
authors.affiliation: Department of Orthopaedic Surgery, Keiyu Hospital, 3-7-3 Minatomirai, Nishi-ku, Yokohama, Kanagawa, 220-8521, Japan.
authors.forename: Soraya
authors.initials: S
authors.lastname: Nishimura
authors.affiliation: Department of Orthopaedic Surgery, Keiyu Hospital, 3-7-3 Minatomirai, Nishi-ku, Yokohama, Kanagawa, 220-8521, Japan.
authors.forename: Michihiro
authors.initials: M
authors.lastname: Kamata
mesh_terms: D000368:Aged; D006801:Humans; D007405:Intervertebral Disc Displacement / Q000150:complications* / Q000000981:diagnostic imaging; D008159:Lumbar Vertebrae / Q000000981:diagnostic imaging* / Q000601:surgery; D008297:Male; D014057:Tomography, X-Ray Computed
keywords: Discography; Lumbar disc herniation; Posterior epidural migration of lumbar disc fragments