Spinal epidural hematomas: personal experience and literature review of more than 1000 cases

OBJECTIVE The goal of this study was to identify factors that contribute to the formation of acute spinal epidural hematoma (SEH) by correlating etiology, age, site, clinical status, and treatment with immediate results and long-term outcomes. METHODS The authors reviewed their series of 15 patients who had been treated for SEH between 1996 and 2012. In addition, the authors reviewed the relevant international literature from 1869 (when SEH was first described) to 2012, collecting a total of 1010 cases. Statistical analysis was performed in 959 (95%) cases that were considered valid for assessing the incidence of age, sex, site, and clinical status at admission, correlating each of these parameters with the treatment results. Statistical analysis was also performed in 720 (71.3%) cases to study the incidence of etiological factors that favor SEH formation: coagulopathy, trauma, spinal puncture, pregnancy, and multifactorial disorders. The clinical status at admission and long-term outcome were studied for each group. Clinical status was assessed using the Neuro-Grade (NG) scale. RESULTS The mean patient age was 47.97 years (range 0-91 years), and a significant proportion of patients were male (60%, p < 0.001). A bimodal distribution has been reported for age at onset with peaks in the 2nd and 6th decades of life. The cause of the SEH was not reported in 42% of cases. The etiology concerned mainly iatrogenic factors (18%), such as coagulopathy or spinal puncture, rather than noniatrogenic factors (29%), such as genetic or metabolic coagulopathy, trauma, and pregnancy. The etiology was multifactorial in 11.1% of cases. The most common sites for SEH were C-6 (n = 293, 31%) and T-12 (n = 208, 22%), with maximum extension of 6 vertebral bodies in 720 cases (75%). At admission, 806 (84%) cases had moderate neurological impairment (NG 2 or 3), and only lumbar hematoma was associated with a good initial clinical neurological status (NG 0 or 1). Surgery was performed in 767 (80%) cases. Mortality was greater in patients older than 40 years of age (9%; p < 0.01). Sex did not influence any of these data (p > 0.05). CONCLUSIONS Factors that contribute to the formation of acute SEH are iatrogenic, not iatrogenic, or multifactorial. The treatment of choice is surgery, and the results of treatment are influenced by the patient's clinical and neurological status at admission, age, and the craniocaudal site.