Os odontoideum in a patient with cervical vertigo: a case report

Os odontoideum: A comprehensive review

Os odontoideum (OO) is a rare craniocervical anomaly that is characterized by a round ossicle separated from the C2 vertebral body. With a controversial etiology and unknown prevalence in the population, OO may be asymptomatic or present in patients with myelopathic and neurological symptoms. In this literature review, we aimed to investigate epidemiology, embryology, pathophysiology, clinical presentation, and the role of diagnostic radiography in OO. By providing an overview of different management strategies, surgical complications, and postoperative considerations for OO, our findings may guide neurosurgeons in providing proper diagnosis and treatment for OO patients. A literature review was conducted using the PubMed, EMBASE, and Scopus databases. A search using the query “os odontoideum” yielded 4319 results, of which 112 articles were chosen and analyzed for insights on factors such as etiology, clinical presentation, and management of OO. The presentation of OO varies widely from asymptomatic cases to severe neurological deficits. Asymptomatic patients can be managed either conservatively or surgically, while symptomatic patients should undergo operative stabilization. Although multiple studies show different techniques for surgical management involving posterior fusion, the diversity of such cases illustrates how treatment must be tailored to the individual patient to prevent complications. Conflicting studies and the paucity of current literature on OO highlight poor comprehension of the condition. Further understanding of the natural history of OO is critical to form evidence-based guidelines for the management of OO patients. More large-center studies are thus needed to promote accurate management of OO patients with optimal outcomes.

What is the best treatment option for cervical spinal cord injury by os odontoideum in a patient with athetoid dystonic cerebral palsy?

Context: Atlantoaxial instability in an athetoid dystonic cerebral palsy patient due to os odentoideum represents a rare cause of high-level cervical spinal cord injury. There is no evidence-based treatment protocol for this injury and a number of reports have debated whether nonsurgical or surgical treatment is the best option.Findings: Here, we report the case of a 32-year-old athetoid dystonic cerebral palsy patient with os odontoideum (OO) causing compressive myelopathy on the C1-2 levels. About two weeks after atlantoaxial fusion, the patient started an intensive rehabilitation program and maintained it for four weeks. He showed neurological and functional improvement at discharge after four weeks of training. There were further improvements in function and symptoms four weeks after discharge.Conclusion: Intensive rehabilitation programs are important for the recovery and good prognosis in spinal cord injury patients. However, rehabilitation of CP patients with spinal cord injury is often neglected. We provided intensive rehabilitation therapy to a patient for a cervical spinal cord injury by OO with athetoid dystonic cerebral palsy and achieved neurological and functional recovery.

Post-traumatic os odontoideum - case presentation and literature review

Os odontoideum is a rare condition. Nevertheless this condition was described by Giacomini in 1886. It is defined radiologicaly as an oval or round-shaped ossicle of variable size with smooth circumferential cortical margins representing the odontoid process that has no continuity with the body of C2. It is important to review this topic since the upper cervical spinal region is complex from anatomical point of view and has many vital structures passing in close relation to each other. If a person suffers from hyper mobile dens due to insufficiency of its ligamentous complex, it may cause translation of the atlas on the axis and may compress the cervical cord or vertebral arteries. There are cases where patients suffering from Os odontoideum became quadriplegic after a minor trauma. This lesion usually present in pediatric population and its cause is widely debatable today. In our paper we present a review of Os odontoideum in general and present a specific case of a young woman that was diagnosed with Os odontoideum together with the methods that were used to examine, stabilize and finally treat her.

Fracture of the odontoid process in a male individual from the medieval necropolis of Maro (Málaga, Spain)

Traumatic injuries are commonly reported in paleopathology. However, fractures of the odontoid process in past populations are uncommon and therefore such injuries may be easily overlooked. This paper describes alterations of the first and second cervical vertebrae, the atlas and axis, of a male individual of advanced age from the medieval necropolis of Maro (Málaga, Spain). These alterations were observed through macroscopic evaluation and radiological analysis. This individual's skeleton is well-preserved, with degenerative changes present in the appendicular skeleton and the rest of the vertebrae. Our differential diagnosis included aplasia of the dens, bifid dens, dens duplicated, ossiculum terminale persistens, os odontoideum, and odontoid process fractures. We concluded that the most likely condition was a broken odontoid process fused with the anterior arch of the atlas, a pseudarthrosis demonstrating that the individual survived this fracture. This study is one of the first reports of an odontoid process fracture in ancient contexts.

Atlantoaxial Subluxation due to an Os Odontoideum in an Achondroplastic Adult: Report of a Case and Review of the Literature

The authors report the first example of an adult achondroplastic dwarf with progressive quadriparesis secondary to atlantoaxial subluxation as a consequence of an os odontoideum. Actually, craniocervical region is a frequent site of compression and myelopathy in achondroplasia particularly in children as a result of small foramen magnum and hypertrophied opisthion. Moreover, very rarely in achondroplastic patients, coexistence of atlantoaxial instability as the sequel of os odontoideum can result in further compression of the already compromised cervicomedullary neural tissues, the scenario that has been reported only in five achondroplastic children. Herein, a 39-year-old achondroplastic male suffering such an extremely rare combination is presented. With C1-C2 screw rod instrumentation, atlas arch laminectomy, limited suboccipital craniectomy, and release of dural fibrous bands, reduction, decompression, and stabilization could be achieved properly resulting in steady but progressive recovery.

[Acute decompensation of os odontoideum in the elderly. Case report]

Os odontoideum is a lesion of the second cervical vertebra, usually revealed by a neurological decompensation due to a neck injury in young adults. We report the exceptional case of an os odontoideum decompensation in a 81-year-old patient, who became quadriplegic after a fall. Subsequent surgical treatment resulted in complete neurological recovery. Os odontoideum can decompensate at all ages, and the authors recommend preventive surgical treatment in cases of instability, including in the elderly.

Os odontoideum: etiology and surgical management

OBJECTIVE

Os odontoideum is an independent ossicle of variable size with smooth circumferential cortical margins separated from the foreshortened odontoid peg. The etiology of os odontoideum remains controversial, but there is now emerging consensus on the traumatic etiology of os odontoideum rather than a congenital source.

RESULTS

We reviewed the literature of os odontoideum. Patients with this condition can be asymptomatic or present with wide range of neurological dysfunctions. Although the diagnosis of os odontoideum can be made with plain x-rays, further imaging modalities including magnetic resonance imaging and computed tomography angiography have improved the preoperative planning.

CONCLUSION

There is a role for conservative treatment of an asymptomatic incidentally found, radiologically stable, and noncompressive os odontoideum. Conversely, surgery has a definite role in symptomatic cases. The main method of surgical treatment today is posterior decompression after reduction and fusion via independent C1 and C2 instrumentation. Irreducible, persistent anterior compression from os odontoideum can be approached by a transoral route with good results in experienced hands.

Upper cervical ligament testing in a patient with os odontoideum presenting with headaches

STUDY DESIGN

Resident's case problem.

BACKGROUND

The role of premanipulative testing of the cervical spine is an area of controversy, and there are very few data to inform and guide practitioners on the use of ligamentous stability tests when assessing the upper cervical spine.

DIAGNOSIS

A 23-year-old female was referred to physical therapy by a neurologist for the management of intractable headaches of possible musculoskeletal origin. Her Neck Disability Index score was 54% and she rated her headache pain from 3/10 to 9/10 on a Numerical Pain Rating Scale. She reported a 2-year history of intermittent lower extremity paresthesias without a known mechanism or current symptoms. She was treated in physical therapy for 11 visits with improvements in cervical range of motion, strength, and intensity of her headaches, but noted no change in the frequency of headaches. She was subsequently referred to the primary author for a second opinion and potential manual therapy interventions. Initial neurological screening examination for upper and lower motor neuron lesions was unremarkable. Assessment of the transverse ligament, using the anterior shear test in supine, brought on paresthesias in both feet and her toes. The paresthesias continued after the cessation of the test. The Sharp-Purser test performed in sitting, immediately after the transverse ligament test, abolished the paresthesias. She was then referred back to her primary care physician for further evaluation. Subsequent radiographs and magnetic resonance imaging revealed that the patient had a C2-C3 Klippel-Feil congenital fusion and os odontoideum. The patient was examined by a neurosurgeon who concluded that she was not a surgical candidate. Her neurological symptoms completely resolved, but she continued to have headaches.

DISCUSSION

Os odontoideum is a clinically important condition, given that the mobile dens may render the transverse ligament incompetent, leading to atlantoaxial instability. Both the role and sequencing of upper cervical ligamentous testing is controversial. The results of this case report suggest that physical therapists should be cognizant of this condition and consider screening the upper cervical ligaments prior to manual or mechanical interventions to this region.

LEVEL OF EVIDENCE

Differential diagnosis, level 4.