Unsuspected agenesis of the odontoid peg in a trauma patient.
Explore the source record for details and available documents.
Accidents, Traffic↗
SEARCH · Search PubMed
Results for “Odontoid Process”
Search indexed PubMed citations on genomics, clinical trials, systematic reviews and public health. Explore titles, authors and supplied subject terms, then open the PubMed record.
Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.
Experimental investigation of failure load and fracture patterns of C2 (axis).
The injury mechanism and magnitude of failure load of C2 fractures are important in the clinical treatment of its fixation. The magnitudes of the failure load of C2 and the mechanism of injury in vivo are uncertain. Accordingly, nine C2 vertebrae obtained from cadaver spines, ranging in age from 51 to 80 years, were used for the study. Special restraint conditions were applied to yield specific fracture of C2. With the posterior element potted postero-anteriorly up to one-quarter of the inferior facet, posterior shear force ranging from 840 to 1220N was required to cause fracture across the pars interarticularis. For odontoid fracture study, a special rig was fabricated to encapsulate the body of C2 in a cell using ISOPON, and a thin layer of ISOPON sandwiched between the inferior facets and two lateral plates. The assembled rig permits slight sagittal movement of C2 about the cup lateral pivot supports. Failure load of between 900 and 1500N was recorded for odontoid fracture. These values are in agreement with published data. The experiment carried out under these two different restraint conditions had specifically resulted in different fractures of C2. In reality, depending on factors such as the inclination of this force vector applied to the head, the precise posture at the time of trauma, the spinal geometry, and the physical properties, different types of fracture patterns of C2 may be produced. This additional data will be useful in the biomechanical study of C2 vertebra using analytical approaches, and in surgical anterior/posterior fixation using screws.
Aged↗
Basilar invagination as a sequela of multisystem Langerhans' cell histiocytosis.
We report the presence of basilar invagination, an unexpected and previously undescribed abnormality of the skull base, in 7 of 38 long-term survivors of multisystem Langerhans' cell histiocytosis. The abnormality is acquired, but its pathogenesis is uncertain.
Adolescent↗
[Retro-odontoid synovial cyst with Forestier's disease].
STUDY DESIGN: We report one case of 66-year-old man with Forestier disease and spinal cord compression by retro-odontoid synovial cyst. OBJECTIVES AND METHODS: Although retro-odontoid synovial cysts remain rare, an increasing number have been reported in the literature. Affecting adults in the sixth decade of life, retro-odontoid synovial cysts produce slowly progressive upper spinal cord symptoms. Diagnosis can be achieved by means of magnetic resonance imaging (MRI). Association with Forestier's disease has been reported in only one previous study. Cyst probably develop as a result of enhanced mechanical stress on the only remaining mobile joint. In the literature treatment of retro-odontoid mass associated with Forestier has usually involved occipito-cervical fusion with transoral decompression. RESULTS: In this report we describe a patient treated by the posterolateral route with good short- and mid-term clinical and radiological outcome. CONCLUSIONS: In comparison of transoral route, the advantages of the posterolatral route are shorter hospitalization and lower morbidity especially in elderly patients with operative risk factors.
Aged↗
Cervical trauma: rationale for selecting the appropriate fusion technique.
The selection of the appropriate surgical approach in the management of an unstable cervical spine injury is predicated on the biomechanic deficiencies of the bony and ligamentous structures, the age of the patient, the level of experience of the surgeon, and the concomitant medical comorbidities. The optimal approach ideally is the least invasive, provides the greatest benefit-to-risk ratio in terms of potential injury to contiguous neurovascular structures, and provides adequate stabilization to avoid cumbersome external immobilization and allows early rehabilitation. This article discusses anterior, posterior, and combined stabilization techniques in patients who have sustained trauma to the upper and lower cervical spine.
Atlanto-Occipital Joint↗
Orthopedic problems of the shoulder and neck.
If one excludes trauma, problems of the neck and shoulder in children are relatively uncommon. Still, the pediatrician or family practitioner should have sufficient familiarity to provide the family with appropriate counseling and referral. This article emphasizes the common problems, but also notes less common conditions that, if unrecognized, may have serious impact on the health and well-being of the child.
Axis, Cervical Vertebra↗
Differential treatment in acute upper cervical spine injuries: a critical review of a single-institution series.
BACKGROUND: A single-institution series of injuries of the upper cervical spine are analyzed retrospectively and the literature relevant to the topic is reviewed. METHODS: Seventy patients (34 female, 36 male, mean age 47 years) were admitted during a 5-year period for injuries of the upper cervical spine. Sixty-five were followed for a mean time of 18 months. Three isolated ligamentous instabilities, 6 isolated C1 fractures, 3 complex C2 fractures, 10 combined C1/C2, and 48 C2 fractures (17 hangman's, 31 odontoid) were diagnosed. Twenty-nine patients were treated conservatively and for 41 patients surgery was the primary treatment. Twenty-three ventral odontoid screw fixations, 8 ventral platings and 10 dorsal stabilizations were performed. Stability was evaluated using flexion-extension radiography. Pain levels and neurological outcome were assessed. RESULTS: Operative mortality and neurological morbidity were 0%. Two wound infections and 3 instabilities (17%) in odontoid Type II fractures primarily treated with ventral odontoid screw fixation needed dorsal restabilization. During follow-up examinations the neurological status of three patients was improved. In 62 patients preoperative status was attained. Six patients evaluated their pain as severe, two as disabling. CONCLUSIONS: Candidates for surgery as the primary treatment include those with isolated ligamentous instabilities, Type III hangman's fractures and Type II odontoid fractures with dislocation more than 5 mm. In combined C1/C2 fractures the axis fracture dictates the treatment strategy. Patients who undergo dorsal procedures and have involvement of C1 have a greater chance of developing persistent pain.
Acute Disease↗
Vertebral artery pseudoaneurysm complicating posterior C1-2 transarticular screw fixation: case report.
BACKGROUND: Vertebral artery injury during posterior C1-2 transarticular screw fixation occurs in approximately 3% of patients and may remain asymptomatic or result in arteriovenous fistulae, occlusion, narrowing, or dissection of the vertebral artery, and lead to transient ischemic attacks, stroke, or death. CASE DESCRIPTION: This is the first report of a pseudoaneurysm resulting from damage to the vertebral artery during the procedure. This 31-year-old male underwent posterior C1-2 transarticular screw fixation for unstable os odontoideum. Injury to the left vertebral artery occurred while the hole for the left screw was being drilled. Temporary control of bleeding with local pressure was followed by immediate postoperative angiography that revealed a left vertebral artery pseudoaneurysm. Although the patient remained asymptomatic, therapeutic anticoagulation was instituted 6 hours postoperatively. Increasing size of the pseudoaneurysm was noted on routine follow-up angiography 4 weeks later. Endovascular occlusion of the pseudoaneurysm and left vertebral artery, with preservation of vertebrobasilar flow through the right vertebral artery, was accomplished without neurological consequence. CONCLUSIONS: Vertebral artery pseudoaneurysm complicating posterior C1-2 transarticular screw fixation may be effectively treated with endovascular approaches.
Adult↗
Retro-odontoid soft tissue mass associated with atlantoaxial subluxation in an elderly patient: a case report.
BACKGROUND: We present the case of an elderly patient with a retro-odontoid soft tissue mass associated with atlanto-axial subluxation. CASE DESCRIPTION: A 74-year-old man was admitted to our hospital with progressive motor weakness in his right arm and neck pain. Radiological examinations revealed atlantoaxial subluxation and diffuse degenerative changes. Cervical MRI revealed a syrinx at the C1 level and a retro-odontoid soft tissue mass that severely compressed the spinal cord. The mass was of low signal intensity on both T1- and T2-weighted images. Conservative therapy could not stop the progression of his symptoms, so posterior decompression via a laminectomy of C1 and occipitocervical fixation was performed. These procedures resulted in an improvement of his neurological condition and in reduction of the mass and the compression of the spinal cord. CONCLUSION: The patient lacked any specific conditions that might have caused chronic atlantoaxial subluxation. The degenerative changes alone might have provoked chronic atlantoaxial subluxation and a subsequent retro-odontoid soft tissue mass. In patients with this condition, posterior fixation without direct removal of the mass should be the first choice for surgical intervention.
Aged↗
Anterior screw fixation of odontoid fractures.
BACKGROUND: Anterior screw fixation is the best treatment for odontoid fractures when the fracture line is horizontal or oblique downward and backward, as it preserves atlantoaxial mobility, especially axial rotation. Some details regarding patient positioning and operative technique need to be stressed to obtain the best results and avoid complications. METHODS: Between 1989 and 1997, we treated 17 cases of odontoid fracture by anterior screw fixation. Only two patients presented with motor neurologic deficit. Fracture line was horizontal in 3 cases and oblique downward and backward in 14 cases. RESULTS: Adequate reduction and fixation was obtained in all cases except one, where posterior displacement of the screw occurred without neurologic complications. Functional result was satisfactory in all cases except two, where we noted significant limitation of cervical rotation. CONCLUSION: Successful anterior screw fixation gives the best anatomical and functional results for odontoid fractures. Correct installation is very important for operative success.
Adolescent↗
Posterior C1-C2 transarticular screw fixation in the treatment of displaced type II odontoid fractures in the geriatric population--review of seven cases.
BACKGROUND: Seven geriatric patients presented with displaced Type II odontoid fractures. All patients underwent a posterior C1-C2 transarticular fixation between November 1994 and December 1996. Ages ranged between 63 and 88 years. METHODS: Fractures were treated with placement of bilateral transarticular screws, allowing immediate fixation, except in one patient, for whom only a unilateral screw was used. An autograft interspinous strut was also placed, allowing three-point fixation. Mean follow-up was 10.6 months. RESULTS: Six patients received rigid fixation and developed a stable union. One patient died before any follow-up could be obtained. Two other patients died within 1 year of unrelated causes. The remaining four patients remain active and independent. One intraoperative vertebral artery injury was identified. No clinical sequalae were noted. CONCLUSION: Posterior transarticular screw fixation is a reasonable option in treating these controversial fractures. Seven geriatric patients tolerated this surgery well, and were mobilized early, avoiding complications related to external immobilization.
Aged↗
Os odontoideum: etiology, diagnosis, and management.
BACKGROUND: There have been few reports of os odontoideum since the initial description. METHODS: Forty-four patients with os odontoideum treated during the period 1980 through 1996 were reviewed. There were 33 males and 11 females. Their ages ranged from 7 to 56 years, with an average of 24.6 years. Five patients with no symptoms were treated conservatively. Thirty-nine patients underwent operative treatment including nine posterior atlantoaxial fusions and 33 occipitocervical fusions. RESULTS: The patients were followed up for one to 16 years, with an average of 6.5 years. Five patients treated conservatively have remained stable. All 39 treated patients achieved solid arthrodesis. The results were satisfactory. CONCLUSIONS: We conclude that fusion is indicated if atlantoaxial instability or clinical symptoms are significant, and that occipitocervical fusion should be considered in the operative management of os odontoideum if atlantoaxial arthrodesis is impossible.
Adolescent↗
Infant involved in a motor vehicle accident.
The authors present and discuss the differential diagnosis for a 7-month-old infant who was seen in the ED after having been involved in a motor vehicle accident. The infant was subsequently found to have an odontoid fracture. Strict attention to the mechanism of injury is emphasized for appropriate evaluation of this patient's condition. An infant who becomes airborne in a car that is extensively damaged deserves an aggressive workup. In a child of this age, examination for subtle or even quite significant injury is difficult. Therefore the focus should be on the potential for injury. This article addresses the rarity of this injury pattern and discusses factors involved in treatment of cervical spine injuries in pediatric patients. The development of the axis and radiography of the cervical spine in pediatric patients are reviewed also. Neurosurgical treatment options are presented. This case also reminds us to ensure parents understand the proper use of a car seat.
Accidents, Traffic↗
Critical ischaemia of the maxilla treated with hyperbaric oxygen.
Explore the source record for details and available documents.
Adolescent↗
Selective paralysis of the upper extremities after odontoid fracture: acute central cord syndrome or cruciate paralysis?
A patient presented with selective paralysis of the arms after having sustained a fall. X-ray of the cervical spine showed a type II odontoid fracture with posterior atlantoaxial dislocation. The diagnosis in the emergency room was cruciate paralysis, which is frequently associated with fractures of axis and/or atlas. However, magnetic resonance imaging (MRI) of the cervical spine revealed a lesion consistent with the acute central cord syndrome (CCS) at the C2-C6 level. The patient underwent posterior atlantoaxial arthrodesis to correct instability and was discharged, without much neurological improvement. Cruciate paralysis has been reported to be associated with fractures of axis and/or atlas, and acute CCS has rarely been associated with the fractures. However, this case illustrates that the lesion responsible for selective paralysis of the upper extremities is not as specific as it had been thought to be, and that it is difficult to accurately identify the level of the cervical cord injury by neurological diagnosis and X-rays alone. Supplementary diagnostic modalities, particularly MRI, are required to make a correct diagnosis and develop a therapeutic strategy.
Acute Disease↗
Displaced odontoid fracture in a 9-month-old child.
A 9-month-old child sustained a displaced odontoid fracture in a motor vehicle accident. She was treated with closed reduction and a Minerva cast for 6 weeks, followed by a collar for an additional 2 weeks. At 5-year follow-up, she had made a complete recovery with solid union, no deformity, and no instability.
Accidents, Traffic↗
Odontoid hypoplasia presenting as torticollis: a discussion of its significance.
Odontoid dysplasias are considered rare but are becoming increasingly recognized. Patients may have no symptoms, localized neck pain, or neurologic symptoms. Because patients with odontoid anomalies have the potential for craniovertebral instability, recognition of the entity is essential. A discussion of the axis, its development and anomalies follows.
Adult↗
[Atypical crowned dens syndrome].
Explore the source record for details and available documents.
Adult↗