Confusion after spine injury: cerebral fat embolism after traumatic rupture of a Tarlov cyst: case report

Abstract

Background: Acute low back pain is a very common symptom and reason for many medical consultations. In some unusual circumstances it could be linked to a rare aetiology.

Case presentation: We report a 70-year-old man with an 8-month history of left posterior thigh and leg pain who had sudden confusion after a fall from standing. It was due to cerebral fat embolism suspected by computed tomography scan, later confirmed by brain magnetic resonance imaging (MRI). A spinal MRI scan was then performed and revealed a sacral fracture which drained into an unknown perineurial cyst (Tarlov cyst). Under medical observation the patient fully recovered within three weeks.

Conclusions: Sacral perineurial cysts are rare, however they remain a potential cause of lumbosacral radiculopathy.

Figure 1

Head CT-scan and MRI image. A. Post contrast head CT-scan: fat droplets in the frontal horns of the lateral ventricles (white arrows). B. Sagittal T₁-weighted head MR image: fat droplets disseminated in the subarachnoid spaces (white arrows).

Figure 2

Sacral cyst CT-scan and MRI image. A. Axial sacral CT-scan: left sacral fracture extending to the S2 radicular cyst (presence of a contralateral cyst at the same level). B. Sagittal T₂-weighted sacral MR image: S2 radicular cyst with two liquids: cerebrospinal fluid with blood sediments (white arrow) and fat droplet (black arrow). C. Coronal T₁-weighted sacral MR image: left sacral fracture extending to the radicular cyst (black arrow) which contains cerebrospinal fluid and fat droplets at the bottom (white arrow).