CHRISMED Journal of Health and Research

: 2015  |  Volume : 2  |  Issue : 3  |  Page : 282--285

Three neglected cases of minor trauma to the craniovertebral junction with potentially disastrous consequences

Shruti Chandak, Arjit Agarwal, Shukla Arvind, Joon Pawan 
 Department of Radiodiagnosis, Teerthanker Mahaveer Medical College, Moradabad, Uttar Pradesh, India

Correspondence Address:
Dr. Shruti Chandak
Department of Radiodiagnosis, Teerthanker Mahaveer Medical College, Moradabad, Uttar Pradesh


Os odontoideum is a rare congenital anomaly predisposing to atlantoaxial instability. It may rarely present with a history of trivial trauma followed by slow progressive features of compressive myelopathy. Dens fractures, though not uncommon, may also remain undiagnosed and present later on with nonunion. Hence, it is very important for these patients to undergo proper clinical evaluation and appropriate imaging.

How to cite this article:
Chandak S, Agarwal A, Arvind S, Pawan J. Three neglected cases of minor trauma to the craniovertebral junction with potentially disastrous consequences.CHRISMED J Health Res 2015;2:282-285

How to cite this URL:
Chandak S, Agarwal A, Arvind S, Pawan J. Three neglected cases of minor trauma to the craniovertebral junction with potentially disastrous consequences. CHRISMED J Health Res [serial online] 2015 [cited 2021 Sep 20 ];2:282-285
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Full Text


Minor trauma to the craniovertebral junction is usually ignored by the patients. We present here three cases of minor craniovertebral junction trauma that presented after a few months. Two of the patients (of different ages) had os odontoideum with anterior displacement of the atlanto os complex. One of the patients had a neglected Type II dens fracture with minor displacement. It is important to have a high index of suspicion of craniovertebral junction in patients with minor trauma, because, if negelected, they can lead to catastrophic consequences like compressive myelopathy and quadriparesis. This case report also highlights the fact that in patients with congenital anomalies like os odointoideum, even minor trauma can precipitate atlantoaxial subluxation. The present article is just to reemphasize the importance of looking for and diagnosing cases of trauma to the craniovertebral junction as these cases continue to be neglected even in present day scenario.

 Case Report

Case 1

A 12-year-old child presented to us with a history of fall at home while playing. The patient was allegedly fine just after the fall except for minor neck pain. Hence, he was not evaluated for cervical trauma at that time. He developed progressive quadriparesis (bilateral lower limb weakness first followed by bilateral upper limb weakness) over 4 months. All deep tendon reflexes were brisk. Laboratory evaluation was unremarkable except for mild leukocytosis. A clinical diagnosis of cervical myelopathy was made and the patient was sent for a magnetic resonance imaging (MRI) examination which revealed a well corticated bony lesion anterosuperior to the axis vertebra with hypoplasia of the dens and mild hypertrophy of anterior arch of atlas [Figure 1]. There was about 15 mm anterior displacement of the os over the rest of the axis verterba (increased atlantoaxial distance) with foramen magnum stenosis and resultant compressive myelopathy of the spinal cord. Limited computed tomography (CT) cuts helped confirm the MRI findings [Figure 2].{Figure 1}{Figure 2}

Case 2

A 20-year-old male patient came with a history of sudden fall on the floor at home about 1-month back following that the patient developed weakness of all four limbs. There was a history of similar episode in the past about 1-year back after which the patient had improved on his own without any treatment. On motor examination, there was quadriparesis with brisk deep tendon reflexes. The patient was sent for a radiograph of the cervical spine and cranioverterbal junction with open mouth view. The radiograph showed absence of odontoid process with hypertrophy of arch of atlas [Figure 3]. An MRI was done which showed os odontoideum with about 11 mm anterior subluxation of the os over the rest of the axis. There was also stenosis of foramen magnum with compressive myelopathy of upper cervical cord. CT was done to confirm the MRI findings and showed butterfly vertebra at C7 level [Figure 4] and block vertebrae at T1-T2 level [Figure 5].{Figure 3}{Figure 4}{Figure 5}

Case 3

A 35-year-old male presented with a history of neck pain. He gave a history of motorbike accident about 6 months back immediately after which he was asymptomatic. Later he developed neck pain radiating to both upper limbs. Cervical spine radiograph lateral and open mouth views revealed Type II odontoid fracture with minimal displacement of about 4 mm [Figure 6] and [Figure 7]. MRI showed no evidence ofcompressive myelopathy. Limited CT confirmed the fracture showing it to have uncorticated inferior margin [Figure 8].{Figure 6}{Figure 7}{Figure 8}


The term "os odontoideum," first introduced by Giacomini in 1886, refers to an independent osseous structure lying cephalad to the axis body in the location of the odontoid process. [1] Knowledge of axis ossification centers helps in understanding its anomalies. The dens has 3 ossification centers-2 columnar centers, which ossify before birth and form the body of the dens, and 1 center at the tip of the dens. Os odontoideum results from failure of fusion or fracture of the dentocentral synchondrosis. [2]

Since the gap between the os odontoideum and the axis body usually extends above the level of the superior articular facet of the axis, cruciate ligament incompetence and atlantoaxial instability are common which when present, may lead to substantial narrowing of the spinal canal and cord compression at the level of atlas. [3] Both our patients with os odontoideum had compressive myelopathy for the same reason.

Although os odontoideum may be mistaken for a Type II dens fracture, the well-corticated, convex upper margin of the C2 body and the hypertrophic, rounded anterior arch of C1 help differentiate these 2 conditions. [2] In contrast, the Type 2 odontoid fracture is typically associated with a flattened, sharp, uncorticated margin to the upper axis body and a normal, halfmoon shaped appearance to the anterior atlas arch. [1]

Due to the presence of atlantoaxial instability, minor neck trauma is frequently associated with the onset of symptoms, which may vary from neck or occipital pain to compressive myelopathy, [4] as in both our patients.

Craniovertebral fractures represent 8% to 27% of all cervical spine fractures. [5] Dens fractures account for approximately 5% to 15% of all cervical spine fractures. [6] Dens fractures are classified as Type I, II, or III. A Type I fracture involves only the proximal tip of the odontoid process, while a Type II fracture passes through the base of the odontoid process. A Type III fracture passes through the body of C2. [6]

Fractures of the dens can be seen at any time of life, but are more common in adolescents and elderly. Amling et al. concluded that the "bone structure of the axis is responsible for the location, the distribution and the frequency of fractures of the odontoid process". [7]

A case similar to ours was reported by Bobby et al. [6] wherein trivial trauma led to a Type 2 dens fracture, and the patient presented with fracture after minimal trauma with neurologic symptoms and minimal neck pain.

In conclusion, it is very important to have a high index of suspicion for the diagnosis of congenital cranioverterbal junction anomalies like os odontoideum. Also, fractures of the dens may go unnoticed and neglected for a long period. Appropriate imaging techniques like radiography and multiplanar CT reformation are absolutely necessary for the diagnosis of these problems with MRI as an adjunctive tool to know the condition of the spinal cord and associated compressive myelopathy if any.


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