頭部外傷後に生じた頭蓋頚椎移行部硬膜下血腫の1例

Subdural Hematoma at the Cranio-vertebral Junction Following Head Trauma: A Case Report

Ⅰ．はじめに

　脊髄硬膜下血腫は，頭蓋内硬膜下血腫に比べ稀な疾患である．原因からみると，腰椎穿刺を含む外傷が約85％を占め，残る15％は種々の原因で起こる．しかし，健常な人にこれが起こることは稀で，血小板減少症，白血病，血友病，抗凝固療法などを基礎疾患として有するものが全体の約40％を占める¹³⁾．また，明らかな原因を同定できない特発性脊髄硬膜下血腫も報告されている^7,18)．

　今回われわれは，脊椎・脊髄損傷を伴わず，頭部外傷が原因で発症した頭蓋頚椎移行部から上位頚椎に生じた急性硬膜下血腫の1例を経験したので報告する．

　We report a 62-year-old woman patient who slipped and hit the occipital portion of her skull and suffered an acute spinal subdural hematoma caused by head injury. She complained of headache,neck pain,vomiting,dizziness,and was transferred to our hospital. A skull roentgenogram and CT showed occipital bone fracture and thin subarachnoid hemorrhage,and a small amount of acute subdural hematoma on the contra lateral side. Three hours after the accident,she complained of aggravating neck pain. A repeated CT showed acute subdural hematoma at the cranio-vertebral junction extending to the C3 vertrebral body level. At the emergent operation,we found a dural laceration at the foramen magnum just beneath the fracture,and acute spinal subdural hematoma. After evacuation of the hematoma,the patient recovered completely. Spinal acute subdural hematomas after head injuries are relatively rare. In this case,the migration of the extradural hematoma through the dural laceration at the cranio-vertebral junction was supposed to be responsible for the spinal subdural hematoma. It is crucial that a cervical CT be taken to rule out the possibility of spinal hematoma for patients with head injuries complaining of neck pain.