2025 Volume 12 Pages 493-497
Most pseudoaneurysms after traumatic vertebral artery injuries are caused by penetrating or blunt injuries without vertebral fractures. Here, we report a cervical spinal cord injury in a patient with a giant vertebral artery pseudoaneurysm within a split cervical vertebral fracture. An 82-year-old man presented with a history of complete paralysis of the left side of his body due to basilar artery occlusion. He fell while riding in a wheelchair and presented with obstructive respiratory failure 2 days before transfer to our hospital. Radiological examination revealed C4-5 split fractures with diffuse idiopathic skeletal hyperostosis and a suspected cervical spinal cord injury. A contrast-enhanced lesion was observed within the fracture cavity of the C5 vertebral body, which was suggestive of a pseudoaneurysm originating from the left vertebral artery. Because of a history of basilar artery occlusion and a right vertebral artery that terminated in the posterior inferior cerebellar artery, we did not perform emergency interventional treatment. After conservative treatment under sedation for 3 days, cerebral angiography revealed the almost complete disappearance of the pseudoaneurysm. The patient was deemed to have undergone fracture reduction, posterior decompression, and fusion (C3-7) without risk of aneurysm rupture. Although his neurological recovery was limited, the pseudoaneurysm disappearance and tendency of the fractured vertebral body to fuse were confirmed. Pseudoaneurysms of the vertebral artery associated with vertebral body fractures are extremely rare. This report suggests that pseudoaneurysms within a split cervical vertebral fracture could spontaneously disappear with conservative treatment, with care to avoid rupture and embolism.
Vertebral artery injury occurs in approximately 10% of patients with blunt cervical spine trauma.1,2) Most involve vascular occlusions or luminal narrowing, and pseudoaneurysms are uncommon.1) A treatment strategy for vertebral artery pseudoaneurysms has not yet been established; some reports recommend early surgical intervention,3) whereas others recommend conservative treatment.4) There are few reports of vertebral artery pseudoaneurysms associated with vertebral body fractures.5) In particular, pseudoaneurysms within a fracture are believed to complicate safe reduction. Here, we report a rare case of a patient with a cervical spinal cord injury accompanied by a giant vertebral artery pseudoaneurysm within a split vertebral body fracture.
The patient was an 82-year-old man with a history of basilar artery occlusion who was taking 100 mg of aspirin and had complete paralysis on the left side of his body. He fell while riding in a wheelchair and visited a referring physician for facial swelling. While waiting for an examination at the hospital, an obstructive respiratory disorder developed in the patient, and he was intubated. Radiological examination revealed C4 and C5 vertebral split fractures and a C5 posterior dislocation with diffuse idiopathic skeletal hyperostosis (Fig. 1A). The contrast-enhanced lesion in the fracture cavity of the C5 vertebral body was suspected to be a pseudoaneurysm, with swelling of the tissues behind the pharynx causing obstructive respiratory failure (Fig. 1A). Two days later, the patient was transferred to our hospital for multidisciplinary treatment.
Preoperative radiological examinations. (A) Computed tomography image on the day of injury showing C4 and C5 vertebral split fractures, C5 posterior dislocation, and tissue swelling behind the pharynx (asterisk). (B) T2-weighed magnetic resonance image 2 days after the injury showing spinal cord compression due to C5 posterior dislocation. (C) Cerebral angiography 2 days after the injury showing a giant pseudoaneurysm derived from the left vertebral artery. (D, E) Two-dimensional maximum intensity projection imaging 2 days after the injury showing a pseudoaneurysm (asterisk) extending into the C5 split vertebral body from the fractured C5 left transverse foramen and arteriovenous fistula draining into the epidural venous plexus (arrowheads). (F) Anterior-posterior view of right vertebral angiogram 2 days after the injury showing the posterior inferior cerebellar artery end. (G) Anterior-posterior view of left subclavian angiogram 2 days after the injury showing basilar artery occlusion.
On arrival at our hospital, the patient's manual muscle test score was 2-3 on the right side of the deltoid muscle and distal to it, and his left arm and feet were contracted and completely paralyzed. Although hypoesthesia was observed predominantly on the left side of the lateral humerus and distal to it, a sensation for temperature and pain remained. Because the left side of the patient was paralyzed owing to basilar artery occlusion, the patient was diagnosed with American Spinal Injury Association impairment scale C on the basis of the findings on his right side. Magnetic resonance imaging showed spinal cord compression (Fig. 1B) and a right-dominant intramedullary lesion with a slightly high intensity at the C5 vertebral level. Angiography revealed a giant pseudoaneurysm originating in the left vertebral artery (Fig. 1C). The pseudoaneurysm extending into the C5 split vertebral body from the fracture site of the C5 left transverse foramen and an arteriovenous fistula draining into the epidural venous plexus were observed (Figs. 1D, 1E).
Because of the presence of the right vertebral artery ending in the posterior inferior cerebellar artery (PICA) and the history of basilar artery occlusion (Figs. 1F, 1G), we considered that parent artery occlusion carried a high risk of brain stem infarction. Thus, we did not perform emergency interventional treatment, such as parent artery occlusion, for the pseudoaneurysm and decided to conservatively treat this patient under sedation in the intensive care unit. Five days after the injury, cerebral angiography revealed that the pseudoaneurysm had almost disappeared (Fig. 2). Because the pseudoaneurysm had spontaneously disappeared, we considered that the patient could undergo surgical reduction of the split vertebral bodies by posterior decompression and fusion (C3-7) without the risk of aneurysm rupture. Eight days after the injury, we performed laminectomies at C5-6 and posterior fusion using lateral mass screws at C3-6 and pedicle screws at C7 (Fig. 3A-C). Although we considered fixation at 3 vertebral bodies above and below the fracture (C2-Th1), we chose instead fixation at 2 vertebral bodies above and below the fracture (C3-7) for 3 reasons: 1) the lateral mass of C3 was relatively large, and tracts for insertion with 18 mm screws were obtained; 2) the patient was expected to be inactive postoperatively owing to a history of basilar artery occlusion, and 3) the patient was older and had severe post-traumatic injury, so we sought to minimize the invasiveness of the procedure as much as possible. Computed tomography (CT) revealed that the swelling in the cervical region had been relieved (Fig. 3C), and the patient was extubated 15 days after the injury. However, owing to his unstable respiratory condition, a tracheostomy was performed. Contrast-enhanced CT showed that the pseudoaneurysm had disappeared, and the fractured vertebral body tended toward bony fusion. The patient was then transferred to another hospital for convalescent rehabilitation. Although CT images obtained 3 months later showed that the fractured vertebrae tended to fuse further (Fig. 3D), neurological recovery was limited.
Imaging examination 5 days after the injury. Anterior-posterior view of left subclavian angiogram showing that the pseudoaneurysm had almost disappeared.
Postoperative radiological examinations. (A, B) x-Ray images 20 days after the surgery showing posterior fixation using lateral mass screws and pedicle screws. (C) Computed tomography images 4 days after the surgery showing the reduced fractures and alleviation of tissue swelling behind the pharynx (asterisk). (D) Computed tomography images 96 days after the surgery showing that the fracture had almost fused.
In this report, we describe an extremely rare case of cervical spinal cord injury in a patient with a giant vertebral artery pseudoaneurysm within a split cervical vertebral fracture. Vertebral artery injuries (VAIs), including pseudoaneurysms, occur owing to blunt and penetrating cervical spine trauma (CST). Although the overall number of patients with blunt CST who have VAIs is higher than the number of patients with penetrating CST who have VAIs, the incidence rate of VAI is higher in patients with penetrating CST than in those with blunt CST.1) VAI occurs in approximately 10% of patients with blunt CST.1,2) Most involve vascular occlusion or luminal narrowing, and pseudoaneurysms are uncommon.1) In another report on vertebral artery dissection associated with pseudoaneurysm, pseudoaneurysms accompanied by fractures were not observed in any of these patients, suggesting that such cases are extremely rare.5) Owing to its rarity, an optimal treatment strategy has not been developed.
In 1 study, 112 patients with a total of 120 carotid or vertebral artery dissecting aneurysms were reviewed, among whom 79.2% were managed with conservative treatment.4) Only 13.8% had enlarged pseudoaneurysms; 30.2% were cured, and 56% had stable aneurysms after a mean follow-up period of 29.3 months.4) Although trauma and large aneurysms were regarded as risk factors for aneurysm enlargement,4) most patients showed a good course, and thus, medical treatment can provide a sufficient initial option.4) Another report suggested that most extracranial traumatic carotid and vertebral artery aneurysms due to blunt cerebrovascular injury can be managed with oral aspirin.6) In contrast, the need for early intervention due to concern about rupture has been reported.3) The effectiveness of open surgery,7) parent vessel occlusion,8) flow diverter implantation,3,9) and stent graft implantation10,11) have been reported. However, no clear evidence has been established to support specific treatment strategies.
In the present patient, the location of the pseudoaneurysm within a split vertebral fracture complicated the reduction of the fracture. Initially, endovascular treatment, such as parent vessel occlusion, was considered. However, because the right vertebral artery terminated in the PICA and a history of basilar artery occlusion existed, occlusion of the left vertebral artery was deemed to carry a high risk of brainstem infarction. Although coil embolization or stent-assisted coiling was considered, both were deemed to carry a risk of embolism.12) Therefore, conservative treatment was selected in this case, on the basis of a previous report indicating aneurysm resolution with conservative management.4) In the end, spontaneous occlusion of the pseudoaneurysm was observed while under sedation during the hyperacute phase. It is speculated that the gradual disappearance of the fistula and thrombosis of the pseudoaneurysm might have resulted from insufficient drainage from the pseudoaneurysm to the epidural venous plexus. In addition, the limited space created by the vertebral body fracture may have restricted aneurysm expansion, potentially contributing to thrombosis. At the first angiography, delayed washout of contrast agent was observed in the pseudoaneurysm, suggesting the possibility of thrombosis. These factors may have contributed to the disappearance of the pseudoaneurysm. Overall, when surgery is difficult for patients with a traumatic extracranial vertebral artery pseudoaneurysm within a vertebral fracture, medical management with care taken to avoid rupture and embolism may be a viable treatment option.
Yuta Goto, Hiroya Shimauchi-Ohtaki, and Shunsuke Nakamura were responsible for writing the report, conducting the literature search, extracting and analyzing data, interpreting the results, and updating the reference lists. Fumiaki Honda, Masanori Aihara, Tatsuya Shimizu, Ryosuke Shintoku, Takaaki Miyagishima, Tasuku Yajima, and Masahiro Matsumoto were responsible for extracting and analyzing the data and interpreting the results. Masahiko Tosaka and Soichi Oya provided feedback on the report.
All authors have no conflict of interest.
Because this was a case report, informed consent was obtained from the patient for publication, and an institutional ethical review was deemed unnecessary.
The authors declare that data pertaining to this case report will be made available on request.
