Spinal subdural hematomas are rare; only 15 cases not associated with major trauma have been reported previously. Over the past four years we have encountered eight patients with thrombocytopenia who developed spinal subdural hematomas following lumbar puncture. In three of the patients, the hematoma was associated with weakness and sensory loss in the lower extremities and with bladder dysfunction. One patient recovered spontaneously, but two remained paraplegic until their deaths several months later.
Richard N. Edelson, Norman L. Chernik, Jerome B. Posner. Spinal Subdural Hematomas Complicating Lumbar PunctureOccurrence in Thrombocytopenic Patients. Arch Neurol. 1974;31(2):134–137. doi:10.1001/archneur.1974.00490380082011