Traumatic Retroclival Hematoma: Report of a Novel Mechanism of Injury

Introduction: Retroclival epidural hematoma is a rarely observed injury which has previously been reported almost exclusively in association with high speed motor vehicle accidents. We report on a case arising from a basketball-related injury.

Case Report: A 16-year-old boy fell backward from the height of a jump during a basketball game and struck his occiput on the floor. There was no loss of consciousness but the patient was amnestic to the event. He was taken to an emergency department, where he was intubated after emesis and decline in level of consciousness. CT and MR scans of the patient's brain and cervical spine revealed a retroclival epidural hematoma which remained stable on serial imaging. CT and MR angiography was normal. The patient was extubated the next day and complained of double vision. Neurologic examination revealed only a mild bilateral CN VI palsy. The patient was discharged home in a cervical collar. On follow-up examination2 weeks later, the patient was neurologically intact and the hematoma had resolved.

Literature Review: Retroclival epidural hematomas have recently been reviewed by multiple authors. Including two more recent case reports, there have been approximately 40 patients with retroclival hematoma described in the literature since 1984. The majority of cases were in pediatric patients, although a total of seven adult cases have been reported. Craniovertebral junction injury was identified in 12 cases, all of which were related to high-speed motor vehicle collisions. One spontaneous case has been described. Cases have also been reported in association with posterior fossa decompression for cerebellar infarction, pituitary apoplexy, and from a running fall, which is the only prior report similar to the present case.

Among all reported cases, two patients underwent surgery for hematoma evacuation, and four additional patients underwent surgical stabilization of the craniovertebral junction. There were five fatalities. There were 16 reported instances of associated CN VI palsy, 6 of CN IX palsy, and 9 of CN XII palsy. All except one case of mild bilateral CN VI palsy resolved within 2 months.

Mechanisms for the formation of retroclival epidural hematomas are controversial. Disruption of the tectorial membrane may be an important factor for hematoma formation. Bleeding may arise from the basilar venous plexus, the odontoid arterial arch system, or the anastomotic arterial network involving the neuromeningeal trunk, ascending pharyngeal artery, meningohypophyseal trunk, and inferolateral trunk.

Conclusion: Patients with retroclival epidural hematomas should be evaluated carefully for concurrent injuries. Those with no neurologic deficit, or those with only isolated cranial nerve palsy, can be successfully managed conservatively.