Clinical case-series report of traumatic cauda equina herniation: A pathological phenomena occurring with thoracolumbar and lumbar burst fractures

RATIONALE: Burst fractures in thoracolumbar and lumbar spine typically occur from severe trauma, which may result in cauda equina herniation (CEH). In this study, we attempted to document the incidence and evaluate the sequelae of CEH that were found during decompression and fusion surgery for patients with burst fractures. PATIENT CONCERNS: A total of 416 patients were enrolled in this study. DIAGNOSES: The patients had been operated on through an anterior or posterior approach for treatments of thoracolumbar and lumbar burst fractures at our department between June 1, 2008 and June 1, 2011. INTERVENTIONS: A retrospective analysis of hospital records and a review on radiographs were performed. Data regarding demographics, injury mechanism, radiographs, surgical procedures, outcomes and follow-ups were collected and analyzed. OUTCOMES: The CEH was observed in 49 patients (12%), including 40 males and 9 females with a mean age of 33.7 years old. The posterior approach group included 301 patients (215 males and 86 females), with 13% incident rate for CEH (40/301). The anterior approach group included 115 patients (80 males and 35 females), with 8% incident rate for CEH (9/115). Forty-four patients (90%) with CEH had neurological deficits; while other 5 patients (10%) were neurologically intact but entrapments of a significant proportion of their cauda equina rootlets in the dorsal lamina fracture were observed during operations. Both vertebrae burst fracture and lamina fracture were observed in 95% patients with posterior CEH (38 out of 40). LESSONS: Traumatic CEH were found in 12% of the patients with thoracolumbar and lumbar burst fractures that were treated by surgery. Patients with a lumbar burst fracture showing neurological deficits in combination with a laminar fracture have an increased risk of traumatic CEH.