Odontoid Process Of C2 Research Articles

Quantification of pediatric cervical spine growth at the cranio-vertebral junction.

ObjectiveThe purpose of this study was to investigate morphological change at the craniovertebral junction (CVJ) region using computed tomography.MethodsA total of 238 patients were included in this study, and mean age was 47.8±21.3 months. Spinal canal diameter, Power's ratio, McRae line, antero-posterior C1 ring height, atlantoaxial joint space, C2 growth, epidural space from the dens (M-PB-C2) and longitudinal distance (basion to C2 lower margin, B-C2) were measured. The mean value of each parameter was assessed for individual age groups. The cohorts were then divided into three larger age groups : infancy (I) (≤2 years), very early (VE) childhood (2-5 years) and early (E) childhood (5≥ years).ResultsSpinal canal diameter increased with age; however, this value did not increase with statistical significance after VE age. A significant age-related difference was found for all C2 body and odontoid parameters (p<0.05). Mean McRae line was 8.5, 8, and 7.5 mm in the I, VE, and E groups, respectively. The M-PB-C2 line showed up-and-down dynamic change during early pediatric periods.ConclusionExpansion of the spinal canal was restricted to the very early childhood period (less than 5 years) in the CVJ region; however, the C2 body and odontoid process increased continuously with age. The above results induced a dynamic change in the M-PB-C2 line. Although C2 longitudinal growth continued with age, the McRae line showed relatively little change.

3D Endoscopic Endonasal Approach in Skull Base Surgery: Experience on 87 Consecutive Patients

Objectives: Assess advantages and disadvantages of 3-dimensional endoscopy in the transnasal approach to sellar region, posterior skull base, and cervical junction. Methods: Between January 2012 and December 2013, 87 patients were consecutively treated at the Neurosurgery Division of the University of Turin for sellar, skull base, and cervical junction pathologies. All procedures were performed by the same team (2 ENT surgeons and 2 neurosurgeons) using a 3-dimensional (3D) stereoendoscope (VSII system, Visionsense Ltd, Petach Tikva, Israel). After each procedure each surgeon was asked to fill out a questionnaire (based on visual analogue scales) designed to assess comfort and learning curve. Results: Seventy patients were treated for pituitary macroadenomas, 10 for chordomas, 6 for a malformation of the cervical junction, and 1 for a chondrosarcoma of the odontoid process of C2. A cerebrospinal fluid (CSF) leak was observed in 6 out of 70 patients, 1 out of 10 patients, and 0 out of 7 patients, respectively; 5 out of 7 CSF leaks were intraoperatively solved and 2 out of 7 required revision surgery. No vascular complications were recorded. Median global comfort score (sensation of strain + dizziness + system ergonomics scores), recorded at the end of the first and second procedure, was 9.1 and 9.6, respectively; after the third procedure it reached 10. The learning curve score reached the maximum level of 9.5 after the eighth procedure. Conclusions: 3D stereoscopic vision system is comfortable for the surgeons allowing them to have a better visualization of anatomic structures and landmarks; it is easy to use and after only a few procedures surgeon skills reach high levels.

The selective odontoidectomy: endoscopic endonasal approach to the craniocervical junction.

The resection of the odontoid process via an extended endoscopic endonasal approach has been recently proposed as an alternative to the microscopic transoral method. We aimed to delineate a minimally invasive endoscopic transnasal odontoidectomy and to describe the endoscopic anatomy of the anterior craniovertebral junction (CVJ). The anterior CVJ of 14 fresh adult cadavers were selectively accessed via a binostril endoscopic endonasal approach using 0- and 30-degree endoscopes. The nasopharynx was widely exposed without removing any of the turbinates and without performing a sphenoidotomy. Occipital condyles and lateral masses of the C1 vertebra have been exposed inferiorly at lateral margins of the exposure, in addition to the foramen lacerum, which came into view at the superolateral corner of the operative field. The anterior arch of C1 and the upper 1.5 cm of the odontoid process of C2 have been removed via a minimally invasive endoscopic transnasal approach in all dissections. We propose the selective odontoidectomy as a minimally invasive method for the endoscopic endonasal removal of the odontoid process. By using this approach, turbinates and the sphenoid sinus remain unharmed. In addition, this approach may be used in exposing pathologies situated laterally at the anterior CVJ, such as the lateral masses of atlas and occipital condyles.

Transoral C2 biopsy and vertebroplasty.

Pathologic fractures involving the C2 vertebral body and odontoid process pose a unique dilemma, as the surgical approach for direct odontoid process screw fixation has several limitations. There have been a small number of transoral approach C2 vertebroplasty or kyphoplasty reported in the literature. Previous attempts were performed utilizing fluoroscopy or CT guidance. We report a case of a fluoroscopically guided transor-al approach vertebroplasty in a patient with a lytic lesion involving the C2 vertebral body, extending into the odontoid process with an underlying pathologic fracture. This case is unique as two separate punctures were required in order to adequately stabilize the pathologic fracture, CTA was performed preoperatively to better evaluate regional vasculature, and a post-procedure rotational flat panel CT was performed to assess cement placement.

A case of traumatic intracranial vertebral artery injury presenting with life-threatening symptoms

Traumatic intracranial vertebral artery injury is a relatively rare but potentially fatal disease. We present a case of a 63-year-old man who presented with sudden onset of loss of consciousness after hitting his head. After immediate resuscitation, he showed quadriplegia and absence of spontaneous breathing. Brain and cervical spine magnetic resonance imaging revealed an atlantoaxial subluxation, fractured C2 odontoid process, left vertebral artery occlusion, and bilateral extensive ischemia in the medulla oblongata and high cervical spinal cord. Digital subtraction angiography demonstrated left vertebral artery dissection just below the level of vertebral body C2.

Cervical Fibrous Dysplasia Presenting as a Pathologic Fracture in an Older Patient

Vertebral involvement of fibrous dysplasia (FD) is rare, especially in the cervical spine. Moreover, cervical FD presenting as a pathologic fracture in older patients is extremely rare. We report a case of symptomatic cervical FD associated with pathologic fracture in a 63-year-old man. The patient presented with progressive weakness of the left arm and pain in the shoulder and arm. Radiologic studies revealed a collapsed and typical 'ground glass' radiolucency of C4. Multiple lytic lesions involved the odontoid process of C2 and the body, left pedicle, and posterior elements of C4. Combined anterior and posterior decompression and reconstruction were performed. Post-operatively, the histopathologic examination confirmed FD. On the post-operative follow-up examination, the neurologic deficits had completely resolved.

CT evaluation of Chamberlain's, McGregor's, and McRae's skull-base lines

To evaluate the mean distance from the odontoid process of C2 to the standard skull-base lines (Chamberlain's, McGregor's, and McRae's lines) on computed tomography (CT) imaging. To compare these measurements to previously documented plain radiograph and magnetic resonance imaging (MRI) measurements. Reformatted midline sagittal CT images of 150 adults were retrospectively evaluated. The shortest perpendicular distance was measured from the Chamberlain's, McGregor's and McRae's baselines for each subject to the odontoid tip. Statistical analysis was performed to compare the CT data with the previously obtained MRI and plain film data. The mean position of the odontoid process was 1.4mm below Chamberlain's line (median 1.2 mm, SD 2.4 mm), 0.8 mm (median 0.9 mm, SD 3 mm) below McGregor's line and 5 mm (median 5 mm, SD 1.8 mm) below McRae's line. There is no significant difference between male and female results (p>0.05) or between these CT and previous MRI measurements (p>0.05). These results provide the mean and range of normal distance from the odontoid process to the most frequently used skull-base lines on the current population on CT.

Pure endoscopic endonasal odontoidectomy: anatomical study

Different disorders may produce irreducible atlanto-axial dislocation with compression of the ventral spinal cord. Among the surgical approaches available for a such condition, the transoral resection of the odontoid process is the most often used. The aim of this anatomical study is to demonstrate the possibility of an anterior cervico-medullary decompression through an endoscopic endonasal approach. Three fresh cadaver heads were used. A modified endonasal endoscopic approach was made in all cases. Endoscopic dissections were performed using a rigid endoscope, 4 mm in diameter, 18 cm in length, with 0 degree lenses. Access to the cranio-vertebral junction was possible using a lower trajectory, when compared to that necessary for the sellar region. The choana is entered and the mucosa of the rhinopharynx is dissected and transposed in the oral cavity in order to expose the cranio-vertebral junction and to obtain a mucosal flap useful for the closure. The anterior arch of the atlas and the odontoid process of C2 are removed, thus exposing the dura mater. The endoscopic endonasal approach could be a valid alternative to the transoral approach for anterior odontoidectomy.

4:39136. Anatomy of the C2 Vertebra and Odontoid Process With Relation to Odontoid Screw Placement: A Cadaveric Study of 3,389 Adult Specimens

BACKGROUND CONTEXT: Odontoid fractures account for 10–20% of all cervical fractures. Despite this frequency, their management remains controversial. High rates of nonunion after nonoperative management have led many authors to advocate anterior screw fixation.

Hydatid Cyst of the Craniocervical Junction: Case Report

Although rare in developed countries, hydatid disease is a serious parasitic infection in endemic areas. Spinal disease most commonly involves the thoracic region, and involvement of the upper cervical spine is extremely rare. In this report, a case of hydatid disease involving the craniocervical junction is presented, along with a review of the literature. A 44-year-old man presented with the complaint of neck pain. The results of his physical and neurological examinations were within normal ranges, except for pain exacerbated by neck motion and spasm of the cervical musculature. Magnetic resonance imaging demonstrated a cystic lesion involving the odontoid process and body of C1 and C2, with thin and regular cyst walls and cyst contents similar in intensity to that of cerebrospinal fluid. The results of serological tests performed with the suspected diagnosis of hydatid disease were positive. The patient initially underwent surgery to provide stabilization of the craniocervical junction, using autogenous bone graft and sublaminar wiring from the occiput to C3 via a posterior approach. The cyst was approached via a transoral route, using a U-shaped pharyngeal incision. There were no neurological deficits after surgery. Postoperative magnetic resonance imaging scans confirmed complete excision of the cyst, and the patient was discharged on the 12th postoperative day. He received six cycles of albendazole treatment, each consisting of 28 days with an intervening drug-free period of 2 weeks. Magnetic resonance imaging scans performed 1 year after surgery revealed the patient was still disease-free. Hydatid disease should be considered in the differential diagnosis of spinal cord compression, especially in endemic areas. Although the chance of obtaining a cure is unlikely, radical surgery coupled with antihelminthic therapy seems to provide long-lasting relief.

The borders of the odontoid process of c2 in adults and in children including the estimation of odontoid/body ratio

The odontoid process of C2 projects upward from the superior roof of the body of C2. There is a confusion about the inferior border of the odontoid. The aims of this clinical study were to describe the inferior border of the odontoid process based on the remnant of dentocentral synchondrosis in adults, and the estimation of the odontoid/body ratio in pediatric and adult ages. Sixty-six cases were included for this study. Forty-four of them were in adult ages and the remaining 22 of them were in pediatric ages. The region of occiput, C1, C2, and C3, was examined with the magnetic resonance imaging (MRI) in all cases. The length of the odontoid process was estimated by using radiological images of MR from the tip of the odontoid to the remnant of dentocentral synchondrosis. The portion located under the level of synchondrosis was considered as the body of C2. The average length of the odontoid was 18. 6 mm in pediatric and 21. 3 mm in adult cases. In adult females, the length of the odontoid process (19. 1 mm in length) was smaller than those of adult males (23. 6 mm in length). The average ratio of odontoid/body was two in pediatric and 1.8 in adult cases. This study demonstrated that the neck of the odontoid segment at the level of superior articulating facets is not the synchondrosis between the odontoid process and the body of C2. The synchondrosis is located well below the level of superior articulating facets. It can be demonstrated with sagittal and coronal images of MR in both of pediatric and adult individuals.

DIAGNOSTICS AND TREATMENT FOR UPPER CERVICAL SPINE INJURIES

The experience of diagnostics and treatment of 82 patients with various injuries of the upper cervical spine was analyzed. The most frequent injuries were fractures of C2 odontoid process and arch. The treatment included a wide application of halo apparatus, and, when indicated, a surgical instrumention stabilization of the upper cervical spine.

Combined double fracture of the odontoid process and fracture of the atlas

We report a rare case of double fractures of the odontoid process combined with a fracture of the anterior arch of the atlas. Combined fractures of the odontoid process and the upper cervical spine are not unusual. The presence of two different patterns of odontoid process fractures combined with a fracture of the anterior arch of the atlas is not reported in the literature available to us. The authors report on a patient who sustained two fractures in the odontoid process of C2 and a fracture of the anterior arch of C1. As the initial plain films were not clear enough to detect suspected lesions in the upper cervical spine, the patient underwent full investigation with CT scan and MRI. Reconstructive images showed the fractures of the odontoid process and the one of the atlas. The patient was treated conservatively with the application of cranial traction. The patient died 10 days later of unrelated cardiopulmonary insufficiency. During this period, there was no particular problem from the cervical spine. We recommend a high level of alert and suspicion to every case of upper cervical spine injury since, due to the complexity of the anatomy of this transitional area, a different biomechanical behavior exists leading to a variety of combination of fractures.

An unusual presentation of chronic B‐cell lymphocytic leukaemia

We report a 63-year-old man who was admitted with severe neck pain and tetraparesis. A peripheral blood count showed mild anaemia and lymphocytosis (WBC 43AE5 · 10/l with 78% lymphocytes, Hb concentration 10AE8 g/dl and platelet count 196 · 10/l). Physical examination showed multiple small cervical and inguinal lymph nodes with mild liver and spleen enlargement. Cytological and immunophenotypic studies were typical for B-cell chronic lymphocytic leukaemia (B-CLL) (CD5/CD19, CD23, surface membrane Ig±). Trephine bone marrow biopsy with immunostaining confirmed this diagnosis, showing an interstitial infiltration by small lymphocytes. Chest X-ray examination was normal and abdominal ultrasound tomography showed splenomegaly (17 cm length). Postcontrast sagittal TSET1 512 weighted magnetic resonance imaging scan showed diffusely thickened enhancing meninges of the cervical spine. Leptomeningeal layer involvement is shown (arrow). The cervical spinal cord was compressed and narrowed. Prevertebral soft tissue was involved by an infiltrative neoplastic process. C1 (atlas) and C2 (odontoid) showed irregular enhancing (top). An axial computed tomography scan showed lytic bone destruction that involved the odontoid process of C2 (lower right) and the anterior arc of C1 (left pedicle erosion; lower left). A needle biopsy of the paravertebral neoplastic tissue showed a small-lymphocyte infiltration, consistent with B-CLL localization, while the lumbar puncture showed a normal spinal fluid cell count. The patient was treated with local radiotherapy (30 cGy) and chemotherapy (fludarabine, cyclophosphamide and dexamethasone) with a good haematological response, but persistent neurological impairment. Infiltration or compression of the central nervous system and osteolytic bone lesions are both uncommon in B-CLL, particularly in untreated early stage patients.

O-25-363 - Head trauma patients intubated on admission. Risk of impending cerebral failure

We hypothesized that the entry site of the basivertebral vein into the basivertebral foramen of C2 might localize the subdental synchondrosis between the odontoid process and body of C2, which may be helpful for odontoid fracture classification.Twenty-five dry adult C2 specimens underwent thin-cut computed tomography and were sectioned sagittally. The basivertebral foramen was then correlated to internal bony anatomy. Fifty magnetic resonance images were reviewed, and the location of the subdental synchondrosis was determined.A basivertebral foramen was identified on the posterior surface of all dry C2 specimens. The openings were found at a distance of 30%–44% on an inferosuperior point along the vertical height of C2. For bony specimens with a subdental synchondrosis remnant (75%), entry of acupuncture needles into the basivertebral foramen was always directly at the level of the synchondrosis remnant. For magnetic resonance imaging (MRI), a subdental synchondrosis or its remnants were seen on all studies. The distance from the base of C2 to the subdental synchondrosis ranged from 9–13 mm. This equated to an inferosuperior point 32%–43% along the vertical height of C2. A strong correlation existed when comparing the location of the basivertebral foramen of bony specimens and the subdental synchondrosis location on MRI.The basivertebral foramen is a consistently present anatomic reference point for the subdental synchondrosis even if the latter cannot be seen on conventional radiographic imaging. Our MRI data might also be useful in helping differentiate lesions affecting C2 from normal subdental cartilaginous remnants that can be encountered on imaging.

Biomechanics of upper cervical spine and peculiarities of treatment of patients with odontoid process fractures

In transdental injuries of atlantoaxial region the indications for conservative treatment and authors bipolar Halo-traction method were worked out on the base of spine biomechanical peculiarities (anterior shifting moment and extensor conditionality of the posterior cervical muscles) as well as depending on the mechanism of the development of plane fracture of C2 odontoid process. In flexion fracture of the odontoid process without dislocation as well as in extension fracture with dislocation within the limits of 1/3 of its diameter the successful conservative treatment with plaster thoracocranial bandage was possible. In the rest of cases the authors method of bipolar Halo-traction was indicated. The experience of treatment of 32 patients was used in the work.

A case of successful treatment of chronic transdental dislocation of the atlas using a halo device

Chronic transdental dislocations of the atlas are among the most severe spinal injuries. In this area, the vertebral arteries, spinal cord, cranial nerves are in close contact. According to the literature [3], severe neurological symptoms develop in 25% of cases with fractures of the C2 odontoid process.

Gallium SPECT Detection of Lymphomatous Involvement of the Cervical Dens

Isolated osseous metastases to the odontoid process of C2 are rare with only a few cases reported in the literature. The authors report a rare case of lymphomatous involvement of the cervical dens, initially detected with skeletal and SPECT gallium scintigraphy

Injurious sleep behavior disorders (parasomnias) affecting patients on intensive care units

There are no previous reports on parasomnias (sleep behavior disorders) affecting patients on intensive care units (ICUs). During 8 years of clinical practice, we evaluated over 200 adults with complaints of injurious, sleep-related behaviors, 20 of whom had ICU admissions while their parasomnias had been active and generally undiagnosed/untreated. Mean age during ICU confinement was 62.8 (+/- SD 13.1) years; 85.0% (17/20) were males. Patients underwent comprehensive clinical examinations along with extensive polysomnographic and audiovisual monitoring (electrooculogram, 9 channel EEG with paper speeds of 15 and 30 mm/sec, electromyogram [submental and 4 limbs], EKG, airflow). The polysomnographic studies were diagnostic for the REM sleep behavior disorder (vigorous dream-enactment during rapid eye movement [REM] sleep) in 85.0% (17/20) of patients, and for night terrors/sleepwalking in 15.0% (3/20). Three groups of parasomnia-ICU relationships were identified: i) Parasomnias originating in ICUs, stroke-induced (n = 3); ii) Admission to ICUs resulting from parasomnia-induced injuries: C2 odontoid process fracture and C3 spinous process fracture with severe concussion (n = 2); iii) Parasomnias in patients admitted to ICUs for various other medical problems (n = 15). Physicians should be thus alerted about the possibility of injurious, but usually treatable, parasomnias in ICU patients.