====== Atlanto-axial subluxation case reports ======

===== 2024 =====

A 7-year-old boy with [[Down syndrome]] and [[atlanto-axial subluxation]]. The patient presented with an [[ischemic stroke]] in the left [[hemisphere]] and cervical cord [[compression]] with increased cord [[edema]]. Diagnostic digital subtraction angiography revealed unique patterns of vascular involvement, with retrograde flow through the [[anterior spinal artery]], ascending cervical artery, [[occipital artery]], and multiple leptomeningeal arteries compensating for bilateral vertebral artery occlusion. This case underscores the underreported phenomenon of upward retrograde flow through the anterior spinal artery in bilateral [[vertebral artery occlusion]]. They address the rare manifestation of [[posterior circulation]] involvement in moyamoya syndrome, highlighting the importance of considering atlantoaxial instability as a contributing factor, as the absence of atlantoaxial stability is a risk factor for [[vertebral artery dissection]]. This study contributes valuable insights into the intricate relationship of moyamoya syndrome, Down syndrome, and atlantoaxial instability, urging clinicians to consider multifaceted approaches in diagnosis and treatment. It also emphasizes the potential significance of the anterior spinal artery as a compensatory pathway in complex vascular scenarios
((Abramyan A, Fu AY, Patel K, Sun H, Roychowdhury S, Gupta G. Neurovascular considerations in patients with Down syndrome and moyamoya syndrome. Childs Nerv Syst. 2024 Jan 25. doi: 10.1007/s00381-024-06293-z. Epub ahead of print. PMID: 38273142.))

===== 2021 =====


A young [[woman]] who suffered a severe [[polytrauma]] secondary to a [[motor vehicle]] [[collision]] was diagnosed with a sagittal plane [[atlantoaxial joint]] [[dislocation]] associated with a [[type III odontoid fracture]], despite adequate initial polytrauma management, the neurological damage was too critical, ultimately the decease of the patient.

The atlantoaxial joint dislocation is a rare condition of the [[upper cervical spine]] and is usually secondary to a high-energy traumatism. The disruption of the atlantoaxial ligaments originates the considered most unstable [[cervical spine]] [[lesion]] and with the highest [[mortality]]. Attributable to the kinetic the bone fracture of the [[Atlas]] and [[Axis]] are commonly related, especially the [[odontoid process]]. Early immobilization followed by surgical decompression and stabilization is primordial. Typically, these injuries have an ominous prognosis, that is aggravated if added a polytrauma affecting adjacent neurological structures and other vital organs
((Sánchez-Ortega JF, Vázquez A, Ruiz-Ginés JA, Matovelle PJ, Calatayud JB. Longitudinal atlantoaxial dislocation associated with type III odontoid fracture due to high-energy trauma. Case report and literature review. Spinal Cord Ser Cases. 2021 May 25;7(1):43. doi: 10.1038/s41394-021-00407-4. PMID: 34035212.)).



===== 2020 =====

A patient of atlantoaxial dislocation with persistent first intersegmental artery (PFIA) who presented with posterior circulation stroke. Careful radiological evaluation revealed a loose body (LB) adjacent to the medial aspect of the left C1-C2 facet compressing the anomalous vertebral artery (VA). Intraoperatively, there was a large LB on the postero-medial border of the joint, compressing the VA. The anomalous VA was mobilized, and the offending element removed followed by fixation of the C1-C2.

One should be aware of such an etiology of arterial compromise in cases of atlantoaxial dislocation with co-existent anomalous vertebral artery. An underlying LB or large osteophytes due to instability may be the offending cause, and needs to be dealt with, as fusion alone may not benefit the patient
((Salunke P, Karthigeyan M, Ahuja CK, Panchal C. An unusual cause of
vertebrobasilar insufficiency in a case of atlantoaxial dislocation with
anomalous vertebral artery. World Neurosurg. 2020 Mar 4. pii:
S1878-8750(20)30419-8. doi: 10.1016/j.wneu.2020.02.144. [Epub ahead of print]
PubMed PMID: 32145426.
)).

===== 2019 =====
A 84-year-old man who suffered an observed cardiopulmonary arrest. Cardiopulmonary resuscitation was initiated and spontaneous circulation returned. In the emergency room, the patient's Glasgow Coma Scale was 3 (E1V1M1). No spontaneous respiration was noted. Neuroimaging revealed SAH at the CVJ. Contrast-enhanced computed tomography (CT) revealed a vessel running through the left C2/3 intervertebral foramen into the spinal canal. The ventral space of spinal cord revealed contrast enhancement. Angiography revealed extravasation from the spinal branch of the left vertebral artery, without venous filling. It did not appear to be a vascular malformation with an arteriovenous shunt, but rather a traumatic laceration of the artery. Plain CT and CT angiography suggested AAD. Magnetic resonance imaging revealed injury to the medulla oblongata and upper cervical spinal cord, with AAD and retrodental subligamentous hemorrhage. We embolized the branch of the left vertebral artery and performed a C1 laminectomy. The patient moved his extremities postoperatively.

Discussion: This was a case of injury to the medulla oblongata and upper cervical spinal cord due to AAD with SAH. This is the first report of resuscitated case of traumatic AAD with SAH in the CVJ. Traumatic AAD should be included in the differential diagnosis in case of SAH in CVJ, which may be misdiagnosed as intrinsic SAH
((Kageyama H, Kakumoto K, Yasuoka H, Arimoto H, Ohara Y. Cardiopulmonary arrest induced by atlantoaxial dislocation with subarachnoid hemorrhage: a case report and review of the literature. Spinal Cord Ser Cases. 2019 Dec 12;5(1):100. doi: 10.1038/s41394-019-0247-z. PMID: 33303738.)).
===== 2018 =====

A 30-year-old woman presented with [[neck pain]] and spastic [[quadriparesis]]. Her imaging revealed [[atlantoaxial dislocation]] and bony segmentation defects. Three-dimensional [[computed tomography angiography]] showed bilateral anomalous vertebral arteries (V3 segment) and an [[incidental]] [[aneurysm]] on the arterial segment that crossed the right [[C1]]-[[C2]] joint posteriorly. Because the [[artery]] bearing the aneurysm was non-dominant, it was ligated, and successful C1-C2 posterior reduction and fusion could be performed.

The association of an incidental aneurysm with an anomalous VA in congenital atlantoaxial dislocation (AAD) is unusual. The etiology could be an underlying [[collagen]] defect or repeated shearing-trauma to the vessel wall due to C1-C2 [[instability]]. It would be less risky to proceed with [[endovascular embolization]] followed by [[occipitocervical fusion]] without opening the joints in case the aneurysm is present on dominant aberrant V3 segment. Ventral decompression can be supplemented for irreducible AAD. On the contrary if the aneurysm is present on the non-dominant aberrant V3 segment, the C1-2 joint can be opened and manipulated following an initial endovascular treatment of the aneurysm. If the circumstances demand, the non-dominant artery can be ligated and sacrificed although there is a small risk of formation of stump aneurysm
((Malik P, Salunke P, Kataria M, Karthigeyan M, Ray N. Aneurysm of anomalous V3 
segment in association with congenital atlantoaxial dislocation: Case report and 
challenges in management. World Neurosurg. 2018 Oct 9. pii:
S1878-8750(18)32286-1. doi: 10.1016/j.wneu.2018.09.231. [Epub ahead of print]
PubMed PMID: 30312814.
)).
----
A case of a dislocation happened during a break-dance maneuver. The purpose of this report is describing dangers of break-dancing and discussing the treatment we chose. The patient was followed up until 12 months after surgery. Magnetic resonance imaging and computed tomography of the cervical spine were evaluated. Translaminar fixation of C1/C2 had been performed after manual reposition under X-ray illumination. After a 12-month follow-up, the patient shows a stable condition without neurological dysfunction. He is not allowed to perform any extreme sports
((Petridis AK, Kinzel A, Blaeser K, Thissen J, Maslehaty H, Scholz M. Can
Break-Dance Break Your Neck? C1/C2 Luxation with a Combined Dens Fracture Without
Neurological Deficits in an 11-Year Old Boy After a Break-Dance Performance. Clin
Pract. 2015 Sep 28;5(3):781. eCollection 2015 Sep 28. PubMed PMID: 26664716.
)).