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Forestier disease associated with a retroodontoid mass causing cervicomedullary compression.

OBJECT: Forestier Disease (FD) is a progressive skeletal disorder affecting predominantly older men. It is also known as diffuse idiopathic skeletal hyperostosis (DISH) and is characterized by massive anterior longitudinal ligament calcification that forms a bridge on the anterior border of the thoracic and subaxial cervical spine. To the authors' knowledge, retroodontoid masses associated with FD have not been described. METHODS: Five patients with FD and multilevel subaxial cervical fusion were treated for retroodontoid masses and cervicomedullary junction (CMJ) compression. There were four men and one woman (mean age 73 years, range 54-86 years). All patients suffered progressive neurological symptoms resulting from anterior compression of the CMJ. Four patients underwent combined transoral resection of the ligamentous mass followed by an occipitocervical fusion procedure. One patient with circumferential CMJ compression underwent a posterior decompression and occipitocervical fusion. Histopathological examination of the mass showed hypertrophic degenerative fibrocartilage. Early postoperative neurological improvement was noted in all patients. The follow-up period ranged from 4 to 19 months. At the end of the follow-up period, four patients experienced neurological improvement. One patient died 3 weeks postsurgery of pulmonary complications. CONCLUSIONS: The osseous elements of the occipitoatlantoaxial complex are not directly affected by FD. The ligamentous structures of the odontoid process, however, are exposed to significantly altered biomechanics resulting from fusion of the subaxial cervical spine associated with FD. Stress-induced compensatory ligamentous hypertrophic changes at the craniovertebral junction cause CMJ compression and subsequent neurological deterioration. This previously undescribed entity should be considered in patients with FD or DISH who present with progressive quadriparesis. Transoral decompression and posterior fusion are often needed in patients with large masses and severe progressive neurological deficits. Selected patients with smaller masses and milder neurological symptoms may be treated with posterior fusion alone.

Aged↗

Basilar invagination: a study based on 190 surgically treated patients.

OBJECT: The authors analyzed the cases of 190 patients with basilar invagination that was diagnosed on the basis of criteria laid down in 1939 by Chamberlain to assess the appropriate surgical procedure. METHODS: Depending on the association with Chiari malformation, the anomaly of basilar invagination was classified into two groups. Eighty-eight patients who had basilar invagination but no associated Chiari malformation were assigned to Group I; the remainder of the patients, who had both basilar invagination and Chiari malformation, were assigned to Group II. The principal pathological characteristic was observed to be direct brainstem compression due to odontoid process indentation in Group I and a reduction in posterior cranial fossa volume in Group II. CONCLUSIONS: Despite the anterior concavity of the brainstem in both groups, transoral surgery was the most suitable procedure for those patients in Group I and decompression of the foramen magnum was found to be appropriate for patients in Group II. After surgical decompression, a fixation procedure was found to be necessary in most Group I cases, but only in a small minority of Group II cases.

Adolescent↗

[An unnoticed dislocation of the dens axis in a patient with primary chronic polyarthritis undergoing intensive therapy].

Involvement of the cervical spine is seen in 40%-60% of all patients with rheumatoid arthritis. Consequences are instability of the upper cervical column with pain and neurological deficits, in some cases tetraplegia, and sudden death. From this reason special care has to be taken in the management of those patients, even when they are comatose or anesthetized, to avoid sudden spinal cord compression with irreversible neurological deficits. We report a 49-year-old female with a history of rheumatoid arthritis for more than 10 years. Because of an adhesive ileus complicated by septicemia, she underwent abdominal surgery twice followed by prolonged mechanical ventilation under high doses of sedative drugs. After reduction of the tranquilizer doses tetraplegia with respiratory insufficiency was found. Neurophysiological and X-ray examinations showed spinal cord compression due to dislocation of the odontoid process, a rare but typical complication in patients with rheumatoid arthritis. It was not possible to determine the date of the dislocation, but it might have been caused by intubation or respositioning. Although the patient underwent immobilization and surgical fusion of the upper cervical spine, there was no improvement in the neurological status and she died 5 months later. In patients with advanced rheumatoid arthritis a detailed medical history, clinical examination, and radiography are necessary before general anesthesia or intensive care with intubation is considered. If an unstable cervical spine is suspected, intubation should be performed by fiberoptic technique under light sedation. Regional anesthesia should be preferred over general anesthesia.(ABSTRACT TRUNCATED AT 250 WORDS)

Arthritis, Rheumatoid↗

Chronic atlanto-axial instability in Down syndrome.

We studied the radiographs of thirty-two patients with Down syndrome for evidence of atlanto-axial instability. One of the patients had instability in 1970 and seven had it in 1983. The interval between the atlas and the odontoid process in the patients who demonstrated motion at that interval radiographically averaged 2.78 millimeters in 1970 and 6.93 millimeters in 1983 (p less than 0.005). Four patients whose radiographs showed atlanto-axial motion in 1970 lost that motion by 1983, and in seven patients who did not show atlanto-axial instability in 1970 it developed by 1983. Atlanto-axial instability was more likely to develop in boys who were more than ten years old. Accessory upper-cervical ossicles became evident in three patients, none of whom had atlanto-axial motion. However, one of these three patients had an abnormally wide atlanto-axial interval.

Age Factors↗

Trivial injuries, associated congenital anomaly and medicolegal interpretation of death.

Congenital hypoplasia of the odontoid process is a relatively rare phenomenon. A case is presented of a 12-year-old girl who was admitted to hospital with a history of having sustained trivial external injuries when falling after an alleged push. Later, she developed signs of compression of the spinal cord in the cervical region, resulting in quadriplegia and muscle wasting. A laminectomy was performed to relieve the symptoms but the child died 2 1/2 months later. Autopsy revealed a congenital anomaly of the atlas and axis vertebrae in the form of hypoplasia of the dens. The case being associated with a criminal assault, the post-mortem analysis and autopsy were significant in resolving medicolegal issues pertaining to the assailant, the operating surgeon and the law-enforcement agencies.

Adolescent↗

Cruciate paralysis, hypothesis for injury and recovery.

STUDY DESIGN: Case report and review of the literature. OBJECTIVES: Discuss a case of cruciate paralysis, a review of the literature and the hypotheses regarding the pathogenesis and recovery in spinal cord injuries that cause disproportionate weakness of the upper extremities. SETTING: Thomas Jefferson University Hospital, Philadelphia, PA, USA. METHODS: Case report. RESULTS: A case of cruciate paralysis is presented involving a 59-year-old female who experienced a gunshot wound to the face. Initial motor exams revealed mild lower limb weakness and absent upper limb function with an upper limb modified American Spinal Injury Association motor score of 0/50 (a modified impairment scale using half point muscle grades). Spinal imaging revealed fractures of the C1 anterior ring and the odontoid process, both associated with multiple bullet fragments. No spinal surgery was performed and she was placed in halo fixation. By 3 weeks she had regained enough upper limb function to manipulate large objects with her left hand and move her right hand. At that time, her upper limb ASIA score was 16/50. By 5 weeks, her upper limb modified ASIA motor score had improved to 31.5/50 and she began manipulating feeding utensils, writing legibly, and brushing her teeth with her left hand. CONCLUSIONS: In this case report we present a patient's motor and functional recovery. We also discuss the hypothesis that the acute central cord syndrome and cruciate paralysis are a likely result of similar pathologic mechanisms and that good functional outcome resulted from an initially disabling trauma.

Arm↗

Craniocervical junction synovial cyst associated with atlanto-axial dislocation--case report.

A 51-year-old female presented with a rare case of synovial cyst at the cruciate ligament of the odontoid process associated with atlanto-axial dislocation, manifesting as a history of headache and numbness in her left extremities for 5 months, and progressive motor weakness of her left leg. Neuroimaging studies revealed a small cystic lesion behind the dens, which severely compressed the upper cervical cord, and atlanto-axial dislocation. The cyst was successfully removed via the transcondylar approach. C-1 laminectomy and foramen magnum decompression were also performed. Posterior craniocervical fusion was carried out to stabilize the atlanto-axial dislocation. The cyst contained mucinous material. Histological examination detected synovial cells lining the fibrocartilaginous capsule. Synovial cysts of this region do not have typical symptoms or characteristic radiographic features. Careful preoperative evaluation of the symptoms and a less invasive strategy for removal of the cyst are recommended.

Atlanto-Axial Joint↗

[Modified Kirschner wire insertion for direct ventral screw fixation of dens fractures].

Since 1985 25 patients with a fracture of the odontoid process (dens) were operated in the Neurosurgical Department of the Justus-Liebig-University in Giessen. An early stabilization through an anterior approach was favoured for type II fractures, and for displaced type III injuries, according to the classification of Anderson and d'Alonzo. Two double threaded screws were implanted to reach a compression between the fragments and a stabilization of rotation. With patients having a large thoracic volume and/or a short neck there are often problems, to insert the K-wires in the correct angle, before the screw fixation is performed. For these cases we have developed a new device for the K-wire insertion. After technical examinations in specimen the device was successfully applied in clinical use. This device with its inherent advantages is presented and discussed in this paper.

Bone Screws↗

Hypertrophy of C-1 anterior arch: useful sign to distinguish os odontoideum from acute dens fracture.

Dens fractures are often difficult to detect radiographically because of overlapping structures. The lateral radiographs were examined of all patients at the authors' institution who demonstrated an abnormal odontoid process or an abnormal anterior arch of C-1. Six patients were found: Four had os odontoideum, one had rheumatoid arthritis, and one had a congenital defect in the posterior arch of C-1. All had hypertrophy of the C-1 anterior arch on the lateral view. The width of the anterior arch of C-1 and the cortical thickness of the anterior arch in these six patients were measured and compared with the findings in a control group of 20 patients; the measurements from the six patients were found to be significantly greater. Hypertrophy of the anterior arch of C-1 is a useful sign of a chronic pathologic condition at the atlantoaxial articulation, and in the setting of acute trauma it may be an important clue that prevents unnecessary invasive treatment for a mistaken diagnosis of fractured dens.

Acute Disease↗

[Evaluation of 138 fractures of the cervical spine during a recent 5-year period (1979 to 1983). Therapeutic approaches].

138 cervical spine fractures are reviewed during a recent period of 5 years (1979-1983). Their frequency stay high. The serial concern 67% of men and 33% of women. We observe a peak age between 20 and 30 (23%). 65% of lesions are caused by a traffic injury, 27% by a falling down, 10% by a diving. 45% of cases interest the upper cervical spine (C1-C2) with a high proportion of odontoid process fractures (60%) and Hangman's fractures (30%); 54% of cases concern the lower cervical spine (C3-C7) with an important part of fracture-luxation (72%), specially C5-C6 (35%). Clinically, we note almost a same part of fractures without neurological disturbances (54%) and with neurological abnormalities (46%). In this situation, the sensitive and motor loss are often severe (78%). In 40%, the injuries are polytraumatism and association spine lesion, cranio-cerebral lesion is the most frequent (61%). In upper cervical spine fractures, after Crutchfield or Gardner traction, posterior fixation was performed (62%). The treatment was conservative in 30%. In lower cervical spine lesions, a secondary surgical approach by an antero-lateral way was made (53%). The treatment was initially surgical in 13% and conservative in 28%. The mortality rate of this pathology is important (22%; i.e. 30 deaths on 138 cases).

Adult↗

Posterolateral odontoidectomy for irreducible atlantoaxial dislocation: a technical case report.

BACKGROUND CONTEXT: For the treatment of irreducible atlantoaxial dislocation (AAD), anterior decompression has been commonly used by removal of the odontoid process and fixation of the vertebral body by means of the transoral approach. Although the transoral approach has been well established, there are some disadvantages. By contrast, there have been few technical case reports of the posterolateral approach, especially for irreducible AAD. PURPOSE: To describe a technical case report of the posterolateral approach for irreducible AAD, demonstrating the specific advantages. STUDY DESIGN/SETTING: Technical case report. PATIENT SAMPLE: Case report. OUTCOME MEASURES: Report of postoperative symptoms. METHODS/DESCRIPTION: A 74-year-old woman presented with sudden left hemiparesis because of irreducible AAD. She underwent the odontoidectomy and reduction by means of the posterolateral approach. Posterior fixation with instrumentation and an iliac bone graft was performed 16 days later. The results of radiological examinations were satisfactory. The posterolateral approach takes advantage of the particular features of C1-C2 dislocation of irreducible AAD. CONCLUSIONS: We suggest the possibility that the posterolateral approach is feasible and effective in most cases with irreducible AAD.

Aged↗

Fixation of odontoid fractures by an anterior screw.

We have reviewed 81 patients with fractures of the odontoid process treated between May 1983 and July 1997, by anterior screw fixation. There were 29 patients with Anderson and D'Alonzo type-II fractures and 52 with type III. Roy-Camille's classification identified the direction and instability of the fracture. Operative fixation was carried out on 48 men and 33 women with a mean age of 57 years. Associated injuries of the cervical spine were present in 15 patients, neurological signs in 13, and 18 had an Injury Severity Score of more than 15. Nine patients died and 11 were lost to follow-up. Of 61 patients, 56 (92%) achieved bony union at an average of 14.1 weeks. Two patients required a secondary posterior fusion after failure of the index operation. A full range of movement was restored in 43 patients; only six had a limitation of movement greater than 25%. We conclude that anterior screw fixation is effective and practicable in the treatment of fractures of the dens.

Adolescent↗

Occipital-cervical instability.

A retrospective clinicoroentgenographic study was done on 26 patients with atlantoaxial instability, 17 traumatic and nine nontraumatic. All were treated by means of surgical C1-C2 and occipital-C2 stabilization. The traumatic instability was associated with lesions of the odontoid process and the atlas transverse ligament. Instability may be endogenous or associated with fracture of the atlas. Surgical indication was determined by the level of the fracture line, neurologic symptoms, age, and presence of multiple lesions. C1-C2 stabilization by means of wiring and iliac graft was the selected treatment. Fusion between the occipital and C2 segment was indicated in case of irreducible dens pseudoarthrosis. Fracture on the os odontoideum was very unstable and required greater C1-C2 fusion. Nontraumatic C1-C2 instability was either congenital or secondary to pathologic fractures. Rheumatoid arthritis, which produces anterior displacement of the atlas over the dens to more than 10 mm, neurologic symptoms, or untreatable pain must be stabilized by means of C1-C2 fusion. When elevation of the dens or irreducible displacement of the atlas exists, the results were relatively poor. Tumorous instability produced pathologic fracture of the body of the axis and had to be treated with C1-C2 wiring on bone cement. Down's syndrome instability required occipitoaxial fusion and strict postoperative immobilization.

Adolescent↗

Biomechanical effects of transoral odontoidectomy.

The acute biomechanical effects of transoral odontoidectomy were studied by using qualitative and quantitative methods to assess atlantoaxial motion. In vitro biomechanical testing was performed on the upper cervical spines of eight baboon and five human cadaveric specimens. Using an unconstrained testing apparatus, we performed a flexibility method of testing. Physiological range loading was applied to atlantoaxial specimens, and three-dimensional motion was analyzed with stereophotogrammetry. Force-deformation relationships were delineated in intact specimens and again after surgical removal of the anterior C1 arch, odontoid process, and transverse atlantal ligament. We studied the total range of rotational and linear motions, the behavior of the neutral zone and elastic zone, the flexibility coefficients, and the instantaneous axes of rotation during flexion, extension, bilateral lateral bending, and bilateral axial rotation. Odontoidectomy produced several distinct alterations in motion and in force-deformation responses at C1-C2 that were almost identical in the baboon and human specimens. After odontoidectomy, the atlas developed significantly increased translational movements, which were most prominent in the anteroposterior direction. The total angular range of motion increased significantly during flexion, extension, and lateral bending but not during axial rotation. When the total range of motion was altered, the neutral zone was affected selectively and the elastic zone was spared. Surgery produced mobile, widely spread, unconstrained instantaneous axes of rotation that were in a constrained, fixed position in intact specimens. Clinically, transoral odontoidectomy may predispose patients to spinal instability. Even if acute spinal instability is not apparent, the patients may be susceptible to the delayed effects of the surgery because of the altered anatomy and biomechanical responses.

Aged↗

Transoral-transpharyngeal approach to the craniocervical junction.

The transoral-transpharyngeal approach is a reliable and technically sound method for gaining anterior extradural exposure to the craniocervical junction. We report 23 patients undergoing this approach for pathology lying between the inferior clivus and third cervical vertebra. Pathology included 6 patients with congenital malformations of the odontoid process, 4 patients with basilar invagination caused by rheumatoid arthritis, 2 patients with atlantoaxial subluxation caused by Down's syndrome, and 1 each with Chiari I malformation, pseudogout of C1/C2, ossification of the posterior longitudinal ligament, and chronic dens dislocation caused by trauma. Malignant tumors included 4 chordomas, 2 giant cell tumors of C1-C3, and 1 chondrosarcoma. Orotracheal intubation without tracheotomy was used in 22 patients. Sixteen of these 22 patients were extubated either immediately or within 24 hours. Six complications occurred in 5 patients and included a palatal dehiscence in 2, delayed oropharyngeal hemorrhage, prolonged endotracheal intubation because of severe tongue edema, and 1 case each of meningitis and aspiration pneumonia responsive to intravenous antibiotics. No deaths, local infections, or postoperative cerebrospinal fluid leaks occurred. Neurologic symptoms of cord compression improved or stabilized in all patients. The transoral-transpharyngeal approach is an effective means for extradural decompression of the anterior craniocervical junction and for exposure of selected tumors at this site.

Adolescent↗

Radiology of postnatal skeletal development. XII. The second cervical vertebra.

The development of the second cervical vertebra is complex. The dens (odontoid process) develops two primary ossification centers that usually coalesce within three months following birth. These centers are separated from the primary ossification center of the vertebral centrum by a cartilaginous region--the dentocentral synchondrosis. This synchondrosis is a slow growing, bipolar physis similar to the triradiate cartilage of the acetabulum. It contributes to the overall heights of both the dens as well as the vertebral body. Anatomically the dentocentral synchondrosis is below the level of the C1-C2 articulations. This cartilaginous structure is continuous throughout the vertebral body with similar cartilage in both the facet regions as well as the neurocentral synchondroses. These various cartilaginous continuities progressively close--first, the connections to the facet regions, next the neurocentral synchondroses, and finally the dentocentral synchondrosis. Remnants of the incompletely closed dentocentral synchondrosis must be distinguished from a fracture, which usually propagates along this structure as a physeal injury in infants and children. The cartilaginous epiphysis at the tip of the dens may be transverse or may form a cleft ("V") shape. At eight to ten years, a secondary ossification center--the ossiculum terminale--develops in this proximal dens epiphysis. Fusion of the ossiculum terminale with the rest of the dens occurs between ten and thirteen years.

Age Factors↗

Halo traction in basilar invagination: technical case report.

BACKGROUND: In the management of basilar invagination, traction therapy may help by pulling down the odontoid process away from the brain stem that may result in clinical and radiological improvement. We aimed to discuss the role of the halo vest apparatus traction on the reduction of severe anterior compression pathologies in basilar invagination. CASE DESCRIPTION: We describe a simple and safe cervical traction method by the halo vest apparatus that is followed by rigid posterior occipitocervical fixation and foramen magnum decompression in a patient who presented with basilar invagination and symptoms of severe brain stem compression. An MR-suitable halo vest apparatus was used for reduction of the deformity. The reduction of the basilar invagination was achieved gradually by distracting the halo crown in stages. CONCLUSION: The halo vest apparatus can be safely used in complex craniocervical junction anomalies. An effective cervical traction can be performed in basilar invagination, and reduction of the deformity may be achieved without the risk of overdistraction. In some cases, even partial reduction of the deformity may facilitate brain stem and spinal cord relief without any need of posterior decompression. Patients may benefit from ambulatory functions because bed rest is eliminated in this procedure. Neurovascular structures and the degree of the reduction can be observed on MRIs when an MR-suitable device is used.

Atlanto-Axial Joint↗

An improved version of the cervical vertebral maturation (CVM) method for the assessment of mandibular growth.

The present study aimed to provide a version of the Cervical Vertebral Maturation (CVM) method for the detection of the peak in mandibular growth based on the analysis of the second through fourth cervical vertebrae in a single cephalogram. The morphology of the bodies of the second (odontoid process, C2), third (C3), and fourth (C4) cervical vertebrae were analyzed in six consecutive cephalometric observations (T1 through T6) of 30 orthodontically untreated subjects. Observations for each subject consisted of two consecutive cephalograms comprising the interval of maximum mandibular growth (as assessed by means of the maximum increment in total mandibular length, Co-Gn), together with two earlier consecutive cephalograms and two later consecutive cephalograms. The analysis consisted of both visual and cephalometric appraisals of morphological characteristics of the three cervical vertebrae. The construction of the new version of the CVM method was based on the results of both ANOVA for repeated measures with post-hoc Scheffé's test (P < .05) and discriminant analysis. The new CVM method presents with five maturational stages (Cervical Vertebral Maturation Stage [CVMS] I through CVMS V, instead of Cvs 1 through Cvs 6 in the former CVM method). The peak in mandibular growth occurs between CVMS II and CVMS III, and it has not been reached without the attainment of both CVMS I and CVMS II. CVMS V is recorded at least two years after the peak. The advantages of the new version of the CVM method are that mandibular skeletal maturity can be appraised on a single cephalogram and through the analysis of only the second, third, and fourth cervical vertebrae, which usually are visible even when a protective radiation collar is worn.

Adolescent↗