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PubMed2000

[Atlanto-axial rotation and distance in small children. A postmortem study].

The aetiology of atlanto-axial rotatory subluxation is obscure. Therefore, a post mortem investigation was designed in order to evaluate the C 1-2 rotation and translation mobility and to clear the borderline between mobility and instability and to clear the role of the atlanto-axial joints in atlanto-axial rotatory subluxation. C 1-2 specimen of 2 months, 9 months and 53 months old children were used. In the intact specimen and after sequential decision of the atlanto-axial joint capsule, the atlanto-axial membrane, the transverse ligament of the atlas, and eventually the alar ligaments, the atlas was rotated and anteriorly translated over the axis. The end point of the movements was recorded radiographically. Decision of the anatomic structures increased the rotation of up to 25 degrees. The joint capsules are lax and wide thus allowing rotation with almost complete subluxation. The subluxation of atlanto-axial joints probably stays within the normal range of motion and is not a factor of atlanto-axial rotatory subluxation. Interlocking of the facets could not be observed. In atlanto-axial rotatory subluxation the atlanto-dental interval becomes asymmetric. Its radiographic projection is variable and therefore ist does not present a valuable radiographic parameter.

Age Factors↗
PubMedDate not supplied

Some tips and tricks in reading cervical spine radiographs in trauma patients.

Despite the fact that we are living in the era of spiral CT and multidetector spiral CT allowing us to scan the whole spine in less than a minute and to make high quality multiplanar reformatted images, plain films remain important in clearing the spine of polytraumatised patients. Particularly hemodynamic unstable patients that must be urgently transferred to the operation room need to be rapidly cleared for (cervical) spine lesions, without being transported to the CT unit which is--in most hospitals--located relatively far away from the emergency room and the operation rooms. In these patients, for the time being, spiral CT cannot replace conventional radiographs for the detection of sometimes subtle lesions. Knowledge of the direct but also the indirect signs of fractures remains important in the evaluation of these plain films. This article demonstrates some of these sometimes subtle signs that can help in making the diagnosis of these lesions.

Axis, Cervical Vertebra↗
PubMed2004

[Multidirectional atlantoaxial instability of an os odontoideum in an adult].

Increasing neck pain in a 29 year old woman after a frontal car collision gave reason for a conventional x-ray that presented a traumatically displaced os odontoideum positioned at the top of the dens axis. No neurological defect was seen. Dynamic flexion/extension film showed a movement to an atlantoaxial dislocation with a shift of the os odontoideum. The sclerotic structure of the corresponding bony surfaces was confirmed by computed tomography, whereas magnetic resonance imaging demonstrated a posttraumatic signal change in front of the base of dens axis and os odontoideum. Fusion was achieved by computed navigation with C1/C2 transfacetal screws as described by Magerl and interspinal fusion with a bicortical autologous iliac crest graft and a posterior tension band as described by Brooks. An exact positioning of screws past the asymmetric course of both arteria vertebrales was possible by navigation. The patient was free of pain 5 months after the fusion.

Adult↗
PubMed1996

[Dens fracture and multiple fracture of the thoracic spine after fall from great height. Diagnostic standard].

Multiple level spine fractures after a fall from a great height frequently cause a neurological deficit with paraplegia. In general, survival after a free fall from 20 m height without any neurological deficit is very unlikely. Since a considerable part of the trauma may not be detected by conventional radiograms, it is recommended that CT scans of all affected spine regions always be carried out with 2 D reconstructions. In addition, 3 D reconstructions should be performed if rotatory instability is suspected. This case report illustrates the management and diagnostic problems of a serial spine trauma.

Accidental Falls↗
PubMed2005

Cervical spine and crystal-associated diseases: imaging findings.

The cervical spine may be specifically involved in crystal-associated arthropathies. In this article, we focus on the three common crystals and diseases: hydroxyapatite crystal deposition disease, calcium pyrophosphate dihydrate (CPPD) deposition disease, and monosodium urate crystals (gout). The cervical involvement in crystal-associated diseases may provoke a misleading clinical presentation with acute neck pain, fever, or neurological symptoms. Imaging allows an accurate diagnosis in typical cases with calcific deposits and destructive lesions of the discs and joints. Most of the cases are related to CPPD or hydroxyapatite crystal deposition; gout is much less common.

Adult↗
PubMed2006

A nodular calcification of the alar ligament simulating a fracture in the craniovertebral junction.

We report a case of an incidental nodular calcification of the alar ligament simulating a fracture in the craniovertebral junction of a previously healthy 24-year-old man. Three-dimensional CT and MR imaging revealed a 7.2 x 7.6 x 4.0 mm nodular calcification in the right alar ligament with normal adjacent bony structures. Serial cervical dynamic radiographs and open-mouth views showed that the cervical spine was stable without any change in the calcification.

Adult↗
PubMed1985

Transoral approach for epidural craniocervical pathological processes.

Transoral surgery for ventral craniocervical pathology is an integral part of modern neurosurgery. This approach should be considered in many more cases than in current practice. On the basis of our experiences with 15 operations in 13 patients we feel able to improve the surgical technique in some small details, as 1. the double, two flap incision of the posterior wall of the pharynx, 2. the method of "deep" resection of the odontoid in its high upward and backward position, and 3. insertion of bone grafts and chips in the cavity of tumorous vertebrae for fixation. Admittedly, these cases are not encountered every day in neurosurgical units. An exact knowledge of the anatomical, neurological, pathological, radiological and surgical details is of vital importance and constitutes the basis of this account. This method should not be confined to specialised regional neurosurgical centres, but is within the technical capacity of all trained neurosurgeons.

Adult↗
PubMed1997

Neurological deterioration after posterior wiring of the cervical spine.

Posterior cervical wiring is commonly performed for patients with spinal instability, but has inherent risks. We report eight patients who had neurological deterioration after sublaminar or spinous process wiring of the cervical spine; four had complete injuries of the spinal cord, one had residual leg spasticity and three recovered after transient injuries. We found no relation between the degree of spinal canal encroachment and the severity of the spinal-cord injury, but in all cases neurological worsening appeared to have been caused by either sublaminar wiring or spinous process wiring which had been placed too far anteriorly. Sublaminar wiring has substantial risks and should be used only at atlantoaxial level, and then only after adequate reduction. Fluoroscopic guidance should be used when placing spinous process wires especially when the posterior spinal anatomy is abnormal.

Adolescent↗
PubMed2002

Brachial plexus sonography: a technique for assessing the root level.

OBJECTIVE: Our study was intended to establish a technique to assess the level of the roots of the brachial plexus using high-resolution sonography. MATERIALS AND METHODS: The skeleton of a cervical spine was examined in vitro to determine whether the vertebrae may be identified individually on sonography by means of the evaluation of their transverse processes. Then 20 healthy subjects and five patients who had undergone CT of the cervical spine were evaluated sonographically, and we attempted to identify the level of individual roots of the brachial plexus using the transverse processes as landmarks. To establish the reliability of this method, a blinded review of sonograms of the paravertebral area obtained at various levels was performed independently by three examiners. RESULTS: In vitro, sonography was reliable in depicting the level of the C7 vertebra because of the absence of the anterior tubercle from its transverse processes. In healthy subjects, this feature allowed us to establish the level of the roots outside the spine. In our series, the C4-C7 roots were visible sonographically in all cases, whereas the C8 and T1 levels were seen, respectively, in only 16 of 20 and eight of 20 cases. All examiners correctly identified the C7 level in the blinded review of sonograms. CONCLUSION: High-resolution sonography can reveal the level of the roots of the brachial plexus on the basis of the different morphology of the transverse processes of the vertebrae. Our study has implications for confirming the exact level of pathologic roots before surgery.

Adolescent↗
PubMedDate not supplied

Some upper cervical spine norms.

Lateral cervical spine films from 175 normal examinations of adults performed in the emergency room of North Carolina Baptist Hospital were analyzed to establish some norms and relationships in the upper cervical spine. The predens angle was found to be between 0 degree-13 degrees (mean 5.57 degrees) in neutral position and 0-18 degrees (mean 9.27 degrees) in flexion in most persons. Ninety-two percent of persons have angles greater than 3 degrees in flexion. A V-shaped predens space is not indicative of injury to the cruciate ligament. Virtually every person has posterior slanting or tilting of the dens and the range of values is up to 35 degrees (mean 17.43 degrees). Ninety-eight percent of persons have an angle greater than 6 degrees. A tilted dens does not indicate acute or remote trauma. No relationship was identified between the predens angle and the dens tilt angle. The posterior arch of the atlas can be found at any position between the occiput and spinous process of C2 in all positions of the head and neck. Hence, fanning or widening of the C1-C2 interspinous distance is not a reliable index of ligamentous injury in the upper cervical spine.

Adolescent↗
PubMed2002

New double-door laminoplasty procedure for the axis to preserve all muscular attachments to the spinous process: technical note.

To prevent the occurrence of postoperative cervical malalignment, which is often a complication of conventional axial laminectomy or laminoplasty, the authors developed a new double-door laminoplasty procedure in which the C-2 spinal canal is expanded while all the muscular attachments to each split half of the spinous process remain undisturbed. In conjunction with laminoplasties at other levels, this procedure was performed in five patients with ossification of the posterior longitudinal ligament and cervical myelopathy. Neurological improvement was demonstrated in each patient, and there was no radiological evidence of cervical malalignment. The technique for this procedure is described and its usefulness in preventing postoperative spinal malalignment is discussed.

Axis, Cervical Vertebra↗
PubMed2004

Bipartite atlas with os odontoideum: case report.

STUDY DESIGN: A case report of bipartite atlas associated with os odontoideum and review of the pertinent literature are presented. OBJECTIVE: To illustrate an unusual association of bipartite atlas and os odontoideum and explain the embryological basis. SUMMARY OF BACKGROUND DATA: To the authors' knowledge, only one case of bipartite atlas with os odontoideum had been reported previously. Most of the previously reported cases of bipartite atlas are asymptomatic. METHODS: A 16-year-old boy presented with a 2-month history of weakness and numbness of all four limbs after sustaining a minor head trauma. Radiographs of cervical spine revealed aplasia of anterior arch of atlas, ventral displacement of C1 over C2 on flexion, which reduced on extension. CT scan showed anterior arch aplasia, posterior arch midline defect, and os odontoideum, which had a small projection on the anterior surface at the level of anterior arch. MRI demonstrated increased cord signal at C1-C2 levels on T2-weighted image. Transoral odontoidectomy and posterior fixation of occiput with C2-C3 spinous processes was performed. RESULTS: The patient had significant improvement over next 3 months. CONCLUSIONS: We described a rare association of an anterior arch aplasia, posterior arch defect and os odontoideum. The natural history of patients with os odontoideum suggests that these people have a potentially precarious existence.

Adolescent↗
PubMed1999

Craniocervical injuries in judicial hangings: an anthropologic analysis of six cases.

Restoration projects and archaeologic excavations in two Canadian prisons resulted in the recovery of the skeletons of six felons executed by judicial hanging. Damage inflicted by hanging on various skeletal elements was observed. Among the injuries seen were fractures of the hyoid cornua, styloid processes, occipital bones, and cervical vertebral bodies (C2) and transverse processes (C1, C2, C3, and C5). Despite the general uniformity of the hanging technique, which involved a subaural knot, the trauma to the skeletal elements and the cause of death varied among individuals. Although some of this variation was probably due to minor differences in hanging practices, individual anatomic peculiarities of the victims likely also contributed.

Capital Punishment↗
PubMed1999

Diagnosis of Os odontoideum using kinematic magnetic resonance imaging. A case report.

STUDY DESIGN: A case of os odontoideum diagnosed using kinematic magnetic resonance imaging is presented. OBJECTIVES: To evaluate the kinematic magnetic resonance imaging findings of os odontoideum and the possible use these findings might have to guide treatment. BACKGROUND: Kinematic magnetic resonance imaging is a new imaging modality that is able to produce realtime images of a structure through a range of motion. This makes it well suited for investigating dynamic processes such as cervical instability. METHODS: A single subject with known os odontoideum was examined using a Sigma SPR Kinematic Magnetic Resonance Imager (General Electric, Florence, SC). RESULTS: Kinematic magnetic resonance imaging demonstrated cervical spinal cord impingement and cervical instability throughout flexion and extension, but not during lateral bending or rotation. CONCLUSIONS: Kinematic magnetic resonance imaging can evaluate the cervical spine in an axially loaded position throughout its range of motion. This modality may be a useful method for diagnosing and classifying abnormalities of the spine.

Adult↗
PubMed2005

Chiari malformation Type I and a dolichoodontoid process responsible for sudden cardiorespiratory arrest. Case report.

The authors present the case of an 11-year-old girl who fell from standing height and experienced sudden cardiorespiratory arrest. A Chiari malformation Type I and a dolichoodontoid process were identified, and a brainstem contusion was found that correlated with the patient's clinical signs and symptoms. The authors hypothesize that the dolichoodontoid in a compromised craniocervical space created a contusion in the apposing brainstem at the time of head impact. The patient was left with permanent vocal cord paresis and spastic quadriparesis. Awareness of this rare occurrence is important in managing these congenital abnormalities and in assessing the risk of deterioration.

Abnormalities, Multiple↗
PubMed1991

Os odontoideum with posterior atlantoaxial instability.

Nine patients who had os odontoideum with posterior atlantoaxial instability are reviewed. Three parameters were measured on the lateral radiographs: the distance from the os odontoideum to the spinous process of the axis in extension (Dext), the distance from the os odontoideum to the posterior arch of the atlas (Datl), and the degree of instability (Inst). Patients were classified into four groups: Group I, local symptoms (N = 3); Group II, transient myelopathy (N = 0); Group III, progressive myelopathy (N = 6); and Group IV, cerebral symptoms (N = 0). The development of cervical myelopathy was not related to degree of instability but to distance from the os to the spinous process of the axis (Dext). Dext was more than 16 mm in Group I and less than or equal to 16 mm in Group III. Five of six patients in Group III underwent myelography. Based on myelographic findings, Group III was further subdivided into two groups, Group IIIA (N = 2) and Group IIIB (N = 3), according to the following characteristics: In Group IIIA, the distance from the os to the posterior arch of the atlas was more than 13 mm, and the spinal cord was impinged between the os odontoideum and the lamina of the axis in extension and reduced in flexion. In Group IIIB, Datl was less than or equal to 13 mm, and the spinal cord was compressed at the level of the atlas during flexion and extension. Stenotic Datl of 13 mm or less specifically defined severe cervical myelopathy. Surgical treatment for cervical myelopathy in os odontoideum with posterior instability is suggested as follows: in the absence of canal stenosis of the atlas (Group IIIA), atlantoaxial fusion in a reduced position is indicated; when associated with canal stenosis of the atlas (Group IIIB), laminectomy of the atlas followed by occiput-to-C2 arthrodesis is indispensable.

Adolescent↗