| Article Access Statistics|
| Viewed||3128 |
| Printed||53 |
| Emailed||2 |
| PDF Downloaded||56 |
| Comments ||[Add] |
| Cited by others ||2 |
Click on image for details.
|LETTER TO EDITOR
|Year : 2014 | Volume
| Issue : 3 | Page : 303-304
Congenital defect of the anterior arch of the Atlas: A case report and review of the literature
Ergun Karavelioglu1, Emre Kacar2, Afra Karavelioglu3, Yucel Gonul4, Mustafa Guven5
1 Department of Neurosurgery, Afyon Kocatepe University, Afyonkarahisar, Turkey
2 Department of Radiology, Afyon Kocatepe University, Afyonkarahisar, Turkey
3 Department of Pediatric Surgery, Afyon Kocatepe University, Afyonkarahisar, Turkey
4 Department of Anatomy, Afyon Kocatepe University, Afyonkarahisar, Turkey
5 Department of Neurosurgery, Canakkale 18 Mart University, Canakkale, Turkey
|Date of Web Publication||18-Jul-2014|
Department of Neurosurgery, Afyon Kocatepe University, Afyonkarahisar
Source of Support: None, Conflict of Interest: None
|How to cite this article:|
Karavelioglu E, Kacar E, Karavelioglu A, Gonul Y, Guven M. Congenital defect of the anterior arch of the Atlas: A case report and review of the literature. Neurol India 2014;62:303-4
|How to cite this URL:|
Karavelioglu E, Kacar E, Karavelioglu A, Gonul Y, Guven M. Congenital defect of the anterior arch of the Atlas: A case report and review of the literature. Neurol India [serial online] 2014 [cited 2021 Jan 22];62:303-4. Available from: https://www.neurologyindia.com/text.asp?2014/62/3/303/136974
Congenital anomalies of anterior arch of atlas, such as clefts and partial or total absence are very rare and not well documented. These congenital anomalies are generally considered benign variations and often found incidentally or in a rare patient with a mild neck pain or in patients with neurological signs following minor head or neck trauma. ,,
A 5-year-old girl presented to emergency service with mild neck and abdominal pain after a fall from stairs. Neurological examination was essentially normal. Neck movements were free and of normal range. Liver enzymes were mildly elevated. Abdominal ultrasound findings were normal. Computed tomography (CT) images with maximal intensity projection (MIP) and three-dimensional (3D) reconstruction demonstrated a well-corticated bony defect in the anterior arch of atlas [Figure 1]. Cervical spine T2-weighted magnetic resonance imaging (MRI) also confirmed a bony defect in the anterior arch of atlas [Figure 2]. A congenital abnormality of atlas was diagnosed based on these findings. Patient was treated conservatively with a cervical collar and medication.
Atlas, an essential component of the cranio-vertebral junction, is a transitional structure between the occiput and the spine and consists of three parts: Anterior arch, posterior arch, and lateral masses. Three ossification centers, one anterior and two laterals are located on the atlas. Failure of ossification and fusion of the synchondroses result in the congenital absence of the arch in the developing cervical spine of the infant and child.
|Figure 1: Axial (a) and coronal (b) maximum intensity projection computed tomography (CT) images demonstrate a well-corticated bony defect in the anterior arch of the atlas. Coronal three-dimensional CT image (c) also shows a bony defect of the atlas|
Click here to view
|Figure 2: Axial T2-weighted magnetic resonance image shows a bony defect in the anterior arch of the atlas (arrows)|
Click here to view
Although malformations of the posterior arch of atlas are well documented and rare, malformations of the anterior arch of atlas are not well known and very rare. In their series of 1,354 evaluated cases (CT scan), Senoglu et al., reported 2.95% of posterior arch defects and 0.074% of anterior arch defects.  In another series of 1,153 evaluated cases (CT scans), Kwon et al., reported 0.95% of posterior arch defects and 0.087% of anterior arch defects.  Only seven cases of congenital anomalies of the anterior arch of atlas have been reported, including three cases of absence and four cases of clefts [Table 1]. Of the seven cases, three had history of trauma. Three of the seven cases also had posterior arch defects in addition to congenital anterior arch anomalies. Only one patient had neurologic deficits.
Regardless of the history of upper cervical trauma, congenital anomalies of atlas may cause instability of the atlantoaxial junction, requiring treatment, a cervical collar or surgery. Furthermore, congenital anomalies of atlas, especially clefts, are erroneously considered as fractures in some patients aged below 8 years. In addition, children aged below 3 years represent a distinct subpopulation at particular risk for high cervical and craniovertebral injury.  Differentiating congenital anomalies of atlas from fractures is very important. On imaging, fractures of atlas appear as irregular edges with associated soft tissue swelling, whereas congenital clefts are smooth with an intact cortical wall and no soft tissue swelling.  The CT imaging is the gold standard for differentiating between fractures and congenital anomalies of atlas. 3D CT reconstruction is also very helpful for evaluating anomalies of the atlas.
In conclusion, recognition of these anomalies as benign variants is important to avoid misinterpretation as fractures or subluxations in patients with upper cervical trauma. Surgical treatment should be considered if a neurological deficit or atlantoaxial instability is present.
| » References|| |
|1.||Alvarez Caro F, Pumarada Prieto M, Alvarez Berciano F. Congenital defect of the atlas and axis. A cause of misdiagnosis when evaluating an acute neck trauma. Am J Emerg Med 2008;26:840e1-2. |
|2.||Sabuncuoglu H, Ozdogan S, Karadag D, Timurkaynak E. Congenital hypoplasia of the posterior arch of the atlas: Case report and extensive review of the literature. Turkish Neurosurg 2011;21:97-103. |
|3.||Sharma A, Gaikwad SB, Deol PS, Mishra NK, Kale SS. Partial aplasia of the posterior arch of the atlas with an isolated posterior arch remnant: Findings in the three cases. Am J Neuroradiol 2000;21:1167-71. |
|4.||Senoglu M, Abbasi SS, Theodore N, Bamnakidis NC, Crawford NR, Sonntag VK. The frequency and clinical significance of congenital defects of the posterior and anterior arch of the atlas. J Neurosurg Spine 2007;7:399-402. |
|5.||Kwon JK, Kim MS, Lee GJ. The incidence and clinical implications of congenital defects of atlantal arch. J Korean Neurosurg Soc 2009;46:522-7. |
|6.||Mace SE, Holliday R. Congenital absence of the C1 vertebral arch. Am J Emerg Med 1986;4:326-9. |
|7.||Hosalkar HS, Gerardi JA, Shaw BA. Combined asymptomatic congenital anterior and posterior deficiency of the atlas. Pediatr Radiol 2001;31:810-3. |
|8.||Park SY, Kang DH, Lee CH, Hwang SH. Combined congenital anterior and posterior midline cleft of the atlas associated with asymptomatic lateral atlantoaxial subluxation. J Korean Neurosurg Soc 2006;40:44-6. |
|9.||Thavarajah D, Mckenna P. Congenital absence of the anterior arch of the atlas: A normal variant. Ann R Coll Surg Engl 2012;94:e208-9. |
|10.||Kazanci B, Kahveci R, Ekici MA, Guclu B. Isolated fracture of anterior arch of atlas in a child: Case report and review of the literature. Injury 2013;44:1956-8. |
[Figure 1], [Figure 2]
|This article has been cited by|
||Remote site hemorrhage after intracranial surgeries: is it really benign?
| ||G. Lakshmi Prasad |
| ||British Journal of Neurosurgery. 2016; 30(6): 689 |
|[Pubmed] | [DOI]|
||Cerebral venous overdrainage: an under-recognized complication of cerebrospinal fluid diversion
| ||Kaveh Barami |
| ||Neurosurgical Focus. 2016; 41(3): E9 |
|[Pubmed] | [DOI]|