Prognosis after spinal cord and cauda compression in spontaneous spinal epidural hematomas

Spontaneous spinal epidural hemorrhage (SSEH) warrants urgent surgical treatment in most cases. Which patients will benefit most from decompression is not known and the disease's rarity hampers the collection of large data series to ascertain this. Therefore, using an individual patient data (IPD) meta-analysis, we aimed to identify predictors for outcome and to obtain knowledge on the etiology of SSEH.The IPD meta-analysis is based on raw data from case reports across all studies concerning all variables of interest. The Preferred Reporting Items for Systematic Reviews and Meta-Analyses statement was used. This led to a total of 741 unique pure SSEH patient cases from 487 journal articles. Data were extracted using a data extraction sheet and analyzed using a multivariable logistic regression model.A preoperative Frankel score of C and higher, absence of use of anticoagulants, compression of the cauda equina only, and the extension of the hematoma over 3 or 4 vertebral segments were associated with good outcome. Operative interval was not invariably associated with outcome and hypertension was not a risk factor for developing SSEH.Outcome is mainly determined by severity of preoperative neurologic deficit and use of anticoagulants. Evidence for a venous origin of SSEH is abundant in view of the observed anatomical distribution in different age categories and the absence of hypertension as an isolated risk factor.