Risk assessment of vertebral artery injury in anterior controllable antedisplacement and fusion (ACAF) surgery: a cadaveric and radiologic study.

PURPOSE: We have introduced a novel surgery technique named anterior controllable antedisplacement and fusion (ACAF) for the treatment of ossification of the posterior longitudinal ligament. As reported, the satisfactory postoperative outcome can be attributed to the larger decompression width. However, it may associate with high prevalence of vertebral artery injury (VAI) theoretically. Thus, assessment of the vulnerability of vertebral artery in ACAF is of great importance. METHODS: Computed tomographic scan data of 28 patients were retrospectively studied. Seven radiographic parameters were evaluated: uncinate process (UP) tips distance, transverse foramen (TF)-UP tips distance, TF-LWL (the ipsilateral limited wedging line) distance, the limited distance of lateral decompression, the maximum oblique angle of LWL, TF-LWG (the lateral wall of groove) distance, and width of groove. Eleven fresh cadaveric spines undergoing ACAF surgery were also studied. Two anatomic parameters were evaluated: width of groove and LWG-TF distance. RESULTS: The UP tips distance increased from C3 to C6 and tended to be larger in males. The UP tip-TF distance and LWL-TF distance were smallest at C4, but both were larger than 2 mm. Maximum oblique angle decreased from C3 to C6. Postoperatively, both radiographic and cadaveric measurements showed the width of groove was larger than UP tips distance, but LWG-TF distance was larger than 2 mm in all levels. CONCLUSION: UP can be used as anatomical landmarks to avoid VAI during ACAF surgery. Radiographic and cadaveric measurements verified the safety of ACAF surgery, even for those cases with wedging and lateral slotting.

Vertebral Artery Injury in Cervical Spine Fracture Dislocation: An Observational Study in a Tertiary Care Center.

BACKGROUND: The incidence of traumatic vertebral artery injury (VAI) associated with cervical spine trauma varies widely in published trauma series. The primary aim of this study was to determine the incidence of traumatic VAI in patients who suffered cervical spine injuries by means of routine magnetic resonance imaging, and the secondary objective was to identify any associations with injury mechanism, level of injury, and neurologic injury severity.  Materials and methods: A retrospective review was conducted on 96 patients who suffered cervical spine fracture dislocation with or without an associated spinal cord injury (SCI) in Indian Spinal Injuries Center (ISIC), New Delhi, India from January 2013 to April 2023. Cervical magnetic resonance imaging (MRI) was used to diagnose VAI. Patient's age, sex, cervical injury level, mechanism of injury, neurologic level of injury, association with foraminal fracture, facet dislocation, and clinical sequelae of vertebral artery injury were analyzed. RESULTS: In this study, of 96 patients who met the inclusion criteria, 18 patients (18.75%) had VAI on the MRI study. Thirteen (72.22%) of the eighteen patients had right-sided injuries, four (22.22%) had left-sided injuries, and one (5.55%) had bilateral injuries. There was an associated SCI in every VAI patient. VAI was significantly more common in patients who had ASIA A (61%, n = 11) and ASIA B (22%, n = 4) injuries, and no VAI was noted in neurologically intact patients (p<0.001). The incidence of VAI was higher in the flexion distraction type of injury (n = 12, 66%). The most commonly involved cervical spine injury level was C5-C6 (27%, n = 5), followed by 22% (n = 4) at C4-C5 and C6-C7 levels. About 27.8% (n = 5) of VAI was associated with foraminal fractures, and 72% (n = 13) of VAI was associated with facet dislocations, of which 44% (n = 8) were bifacetal and 28% (n = 5) were unifacetal dislocations. On clinical symptoms, only one (5.56%) patient had a headache, and 17 (94.4%) had no clinical features due to VAI. CONCLUSION: The incidence of traumatic vertebral artery disease is not very uncommon and requires careful and meticulous screening and management. Otherwise, complications like pseudoaneurysm, neurologic deficit, late-onset hemorrhage, infarction, and death can happen. Mostly, it is associated with high-velocity injuries and neurological injuries. MRI can be used as a good screening tool, which can be aided by a CT angiogram or digital subtraction angiography for confirmation. Proper pre-operative evaluation of vascular injury in cervical spine fracture dislocation is very important for patient counseling, patient management, and surgical planning.

Iatrogenic vertebral artery injury with concomitant contralateral idiopathic vertebral artery dissection managed with intravascular intervention: a case report.

Background: Vertebral artery injury (VAI) is a known potential complication of posterior cervical fusion surgery. Pre-operative imaging is used to determine the patency of bilateral vertebral arteries during the planning and execution of surgery. This case illustrates an example of a staged anterior/posterior cervical reconstruction in which an iatrogenic VAI combined with a contralateral idiopathic vertebral artery dissection not identified on pre-operative imaging resulted in absent basilar artery anterograde flow. Case Description: A 61-year-old female underwent planned staged anterior cervical decompression C4-T1 with posterior cervical fusion C2-T4 for the treatment of degenerative cervical myeloradiculopathy. During the second stage posterior fusion, iatrogenic VAI occurred during drilling for placement of the right C2 pars screw. Upon post-operative angiography, in addition to the known right VAI, there was a new left vertebral artery dissection that occurred during/after the anterior stage. The basilar artery was only filled in retrograde fashion from the right internal carotid artery across the right posterior communicating artery. The left vertebral artery dissection was treated with telescoping flow diverting stents to restore flow to the basilar artery and the right VAI was treated with coiling. Conclusions: Surgeons should be aware of the possibility, while rare, that an occult injury to the non-injured artery is always a possibility if significant deformity correction or alignment change has occurred during cervical spine surgery. Working closely with neurointerventional colleagues can be invaluable to quickly assess and if necessary, restore blood flow to the brain through these life saving techniques.

Blunt vertebral vascular injury in trauma patients: ATLS® recommendations and review of current evidence.

Blunt cerebrovascular injury (BCVI) encompasses two distinct clinical entities: traumatic carotid artery injury (TCAI) and traumatic vertebral artery injury (TVAI). The latter is the focus of our review. These are potentially devastating injuries which pose a diagnostic challenge in the acute trauma setting. There is still debate regarding the optimal screening criteria, diagnostic imaging modality and treatment methods. In 2012 the American College of Surgeons proposed criteria for investigating patients with suspected TVAI and subsequent treatment methods, caveated with the statement that evidence is limited and still evolving. Here we review the historical evidence and recent literature relating to these recommendations.