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Acrylic fixation in displaced dens fractures.

Non-union of odontoid process fractures with displacement in old patients have been treated operatively stable acrylic fixation. Immediate mobilization without external fixation was achieved.

Acrylic Resins↗

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.

Adult↗

Congenital atlanto-axial dislocation.

Report about 105 personally operated cases of congenital atlanto-axial dislocation. This fairly common malformation in India occurs three times more in males than in females, 50% show symptoms before the age of 20 years, the other half during the third decade of life. Transient attacks of cervical cord compression occur with progressive motor and posterior column defect, and sometimes unconsciousness and cerebellar involvement are characteristic. The diagnosis is proved by X-rays including tomograms and dynamic studies. Three types of malformation can be differentiated: Group I with assimilation of the atlas, group II with anomalies of the odontoid process and group III with a normal atlas and axis. The different types and subtypes are described in detail as well as the pathological and pathogenic factors. The treatment and personal experiences show that the early treatment with posterior decompression, sometimes combined with posterior fusion was unsuccessful and resulted in a high mortality and morbidity. The antero-lateral approach, described by the author proved to be the method choice. The prognosis is dependent on the extent of the damage to the cord before treatment. Early diagnosis and treatment lead to excellent results.

Adolescent↗

Surgical management of cervical spine injuries.

On the basis of increasing experience, only by keeping strictly to the basic rules, especially through the advantages of a stable internal fixation, better results can be obtained with surgical treatment of cervical spine injuries. For surgical treatment related to the given anatomical situation, the injuries must be subdivided into those above C 3 and the injuries at or below C 3. In injuries above C 3, we would regard the axis body fracture with or without a hangman's fracture and a fresh fracture-dislocation or pseudoarthrosis of the odontoid process as requiring an operation. In injuries above C 3, a posterior modified stabilization without cranial fixation is recommended. The injuries at and below C 3 generally require an anterior approach. With axial deviation, dislocation and fracture-dislocation a stable internal fixation is performed in addition to the fusion of the intervertebral space. With compression and severe compression fractures, the vertebral body is pulled back and firmly fixed by two wires drawn through epidurally behind the vertebral body. The indications for and the late results of early surgical treatment are presented in 125 cases who have undergone such treatment.

Fracture Fixation, Internal↗

Surgery of cervical spine metastases: a retrospective study.

Fifty-one consecutive patients with metastatic lesions of the cervical spine were treated surgically. The most common primary tumor types were breast cancer and myeloma. In 14 (27%) patients, the cervical lesion was the first manifestation of the malignancy. All patients suffered from severe pain but only six had long tract symptoms. Five tetraparetic patients were confined to bed. Vertebral body collapse occurred in 73% of cases. The surgical technique was individualized according to the patient's general condition, the site of metastasis on the vertebra, and the level and number of levels bearing in mind that the treatment is palliative in nature. The goal of treatment was a better quality of life. In the upper cervical spine the technique described by Sjöström et al. was used, if technically possible. If the odontoid process had been totally destroyed, an occipitocervical stabilization was chosen. In the lower cervical spine, an anterior approach was used to resect the tumor growth. Anterior support was provided with bone cement if the patient was not expected to survive long; otherwise bone grafting was used. In cases with two or more levels of involvement, a combined anteroposterior stabilization was usually performed. Good pain relief was achieved postoperatively. The operation was generally well-tolerated by the patients, mild dysphagia being the most common complaint. One patient died 2 days postoperatively of heart failure, giving a postoperative mortality of 2%. Rhizopathy symptoms were relieved totally in 15 patients and partially in 6.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗

Orthopedic and interventional applications at low field MRI with horizontally open configuration. A review.

The recently introduced horizontally open configuration imagers allow imaging of knee, hip or shoulder during whole range of motion, which is not possible in conventional MR imagers. Special joint motion devices can be used to provide accurate and reproducible studies. In cervical spine, functional MR imaging may be useful in evaluating alarligament stability in patients with late sequelae of a whiplash injury, and in patients with rheumatoid arthritis who are clinically suspected of having a cervical myelopathy or superior migration of the odontoid process. In shoulder, full range of motion abduction study may be helpful in assessing the supraspinatus tendon impingement. To evaluate patellofemoral malalignment, quadriceps loading is recommended since associated contracting muscles and related soft tissue structures can be evaluated. The position of the femoral head relative to the acetabulum during different positions can be assessed. Open-configuration scanners provide an access to patients during scanning procedure, and therefore permit interventional procedures to be monitored with MRI. Such interventions include aspiration cytology/biopsy and different drainage procedures.

Arthritis, Rheumatoid↗

[Instability of the upper cervical spine due to rheumatism].

Rheumatic manifestation at the cervical spine occurs in more than 50% of all cases in the natural course of this disease. The first cervical manifestation takes place in the upper cervical spine. The initial involvement of the C1/C2 segment leads to atlantodental subluxation. Progressive destruction can result in vertical instability, which is characterized by cranial subluxation of the odontoid process with the danger of resulting stenosis and cervical myelopathy. The goal of diagnosis has to be the early recognition of these changes to establish an effective treatment protocol. Persistent pain, neurological deficits, and progressive radiological signs for instability are indications for operative stabilizing procedures. These procedures avoid progressive destruction and improve the prognosis regarding pain decrease, regression of neurological deficits, and life expectancy.

Aged↗

Cervical spine in patients with diastrophic dysplasia--radiographic findings in 122 patients.

BACKGROUND: In previous studies, typical radiological findings in the cervical spine of patients with diastrophic dysplasia (DD) have been kyphosis, displacement of the vertebrae, spina bifida occulta (SBO), anterior hypoplasia of vertebrae C3-5, and hyperplasia and dysmorphism of the odontoid process. OBJECTIVES: To make a radiological analysis of the cervical spine in patients with DD. MATERIALS AND METHODS: The study comprised 122 patients (50 males, 72 females), with an average age of 19 years (range newborn-63 years). Follow-up was available on 62 patients (51%), for an average duration of 11 years. Cervical spine alignment was measured according to Cobb's method. The height (H) and depth (D) of the vertebral body and sagittal diameter (S) of the spinal canal were measured. H/D and S/D ratios were then calculated from the measurements. The shape of the vertebrae was assessed. Displacement and movement of cervical vertebrae in neutral and bending radiographs were measured. RESULTS. The average lordosis in the last radiograph was 17(degrees) (range 4 degrees -55(degrees)). Five (4%) patients had a cervical kyphosis with an average of 92(degrees) (range 10-165(degrees)) on their last radiograph. The H/D ratio increased slowly during growth and showed significant correlation with age. There was no growth spurt at puberty. The S/D ratio was fairly stable until 7-8 years of age, when it started to decline slowly. The percentage of vertebrae with a flat vertebral body and narrow spinal canal value tended to increase with age. Vertebral hypoplasia and displacement between vertebrae were most common in the mid-cervical region and resolved spontaneously with age. Degenerative changes seemed to increase with age and were already visible during the second decade of life. SBO was noted in 79% of patients. CONCLUSIONS: The most common alignment in the cervical spine is lordosis in adulthood. The vertebral bodies are flattened and the spinal canal is narrowed. Vertebral body hypoplasia and displacement usually resolve spontaneously during growth. Degenerative changes in the cervical spine are common, but vertebral anomalies are rare. Prevalence of SBO is high.

Adolescent↗

The third occipital condyle, a constituent part of a median occipito-atlanto-odontoid joint: a case report.

A compound conjunction between basiocciput, atlas (anterior arch), and dens of axis (odontoid process) was found incidentally during routine dissection of the head of an 83-year-old man. According to the patient's history, no neck disability had been recorded. A median saw-cut of the head-and-neck conjunction revealed that the basion was anteriorly reinforced by an osseous pillar 4 mm in length and 3 mm in width. Such a formation is known as a third occipital condyle (condylus tertius, CT). In our case it exhibited one surface oriented in an anterior-inferior direction and articulating with the superior border of the anterior arch of the atlas, and another surface oriented in a posterior-inferior direction and articulating with the superior portion of the dens of axis. The dens of axis itself articulated with the anterior arch of the atlas, forming the (normal) median atlanto-axial joint. Post-mortem computed tomography and post-mortem histological examination completed the investigation. The cartilage of the articular compartment between the CT and the anterior arch of the atlas and the related anterior fibrous disc exhibited severe arthrosis. The findings were discussed in the light of developmental and comparative anatomy.

Aged↗

Rheumatoid arthritis of the craniocervical region: assessment and characterization of inflammatory soft tissue proliferations with unenhanced and contrast-enhanced CT.

The aim of this study was to depict and characterize inflammatory soft tissue proliferations caused by rheumatoid arthritis (RA) in the craniocervical region by unenhanced and contrast-enhanced CT. Computed tomography of the craniocervical region was performed in 35 patients in the axial plane before and after the i.v. administration of contrast material. According to the densities and contrast enhancement of the inflammatory soft tissue proliferations, four groups were classified. Ancillary findings, such as a compression of the dural sac or spinal cord, erosions of the bony structures, and atlantoaxial subluxation, were also evaluated. Inflammatory soft tissue proliferations were depicted in 28 of 35 patients and could be differentiated by unenhanced and contrast-enhanced CT according to the above defined criteria: effusion in 6 patients (17%); hypervascular pannus in 8 (23%); hypovascular pannus in 5 (14%); and fibrous tissue in 9 patients (26%). A compression of the dural sac was seen in 11 (31%) patients; 3 of these had neurological symptoms. Erosions of the odontoid process were found in 20 (57%) patients; 16 (80%) of these also showed erosions of the atlas. Atlantoaxial subluxation was seen in 11 (31%) patients. Inflammatory soft tissue proliferations in the craniocervical region caused by RA can be reliably demonstrated and classified by unenhanced and contrast-enhanced CT, which can differentiate between joint effusion and various forms of pannus and depict ancillary findings. Computed tomography is an alternative method for patients unable to undergo an MRI examination.

Arthritis, Rheumatoid↗

Isolated atlantal stenosis in a patient with idiopathic growth hormone deficiency, and Klippel-Feil and Duane's syndromes.

OBJECTIVE AND IMPORTANCE: Isolated atlantal stenosis is very rare with less than ten cases reported, mostly in adult Asians; however, this pathology should be recognized by the neurosurgeon. An unusual case of this rare clinical entity is reported in conjunction with multiple other anomalies. CLINICAL PRESENTATION: We report a Caucasian girl with symptomatic stenosis of the first cervical vertebrae who presented with episodes of loss of tone with subsequent falling, facial cyanosis, urinary incontinence, hand weakness, and difficulties with swallowing. This patient also had the diagnoses of Duane's and Klippel-Feil syndromes, and idiopathic growth hormone deficiency. In addition, this patient was found to have retroflexion of the odontoid process, which further compromised the spinal canal. Flexion-extension radiographs failed to identify cervical spine instability. INTERVENTION: Following suboccipital craniectomy and the removal of the posterior arch of the atlas, the patient's symptoms were resolved and her urinary incontinence improved. CONCLUSIONS: We theorize that our case represents a variant of Wildervanck syndrome. Further case reports are necessary to verify that isolated atlantal stenosis is a component of this constellation of findings. Furthermore, our case demonstrates that degenerative changes of the spine are not necessary for the production of symptoms in cases of isolated stenosis of the atlas.

Child↗

A clinico-pathological study of cervical myelopathy in rheumatoid arthritis: post-mortem analysis of two cases.

Two patients who developed cervical myelopathy secondary to rheumatoid arthritis were analyzed post mortem. One patient had anterior atlanto-axial subluxation (AAS) combined with subaxial subluxation (SS), and the other had vertical subluxation (VS) combined with SS. In the patient with AAS, the posterior aspect of the spinal cord demonstrated severe constriction at the C2 segment, which arose from dynamic osseous compression by the C1 posterior arch. A histological cross-section of the spinal cord at the segment was characterized by distinct necrosis in the posterior white columns and the gray matter. In the patient with VS, the upper cervical cord and medulla oblongata showed angulation over the invaginated odontoid process, whereas no significant pathological changes were observed. At the level of SS, the spinal cord was pinched and compressed between the upper corner of the vertebral body and the lower edge of the lamina. Histologically, demyelination and gliosis were observed in the posterior and lateral white columns.

Arthritis, Rheumatoid↗

Acute presentation of hydromyelia in a child.

The authors document a rapid development, within 3 weeks, of hydromyelia in a 12 year-old boy. The boy was admitted to a local hospital because of drowsiness and persistent severe neck pain. Neurological examination disclosed a lethargic boy with no neurological deficit other than Parinaud's sign. During his transfer to our department, he presented a cardio-respiratory arrest with coma and bilateral mydriasis. External ventricular drain and craniocervical decompression achieved excellent clinical and neuroradiological outcomes. The development of hydromyelia in this case is caused by obstruction to the natural cerebrospinal fluid pathway at the craniocervical junction and the cardio-respiratory arrest is provoked by a brain stem compression against the clivus and odontoid process. This report illustrates that hydromyelia may complicate acute obstructive hydrocephalus due to acquired Chiari malformation.

Arnold-Chiari Malformation↗

The lateral transfacetal retrovascular approach for an anteriorly located chordoma originating from the second cervical vertebra.

BACKGROUND: Anteriorly located lesions at the craniocervical junction (CCJ) require careful surgical planning to avoid neuraxis retraction. Several different routes have been described in the search for the most appropriate yet least invasive approach. However, most of these far-lateral posterior approaches are specifically tailored for non-osseous intradural tumours or chordomas with cephalad extension. We introduce an approach that allows for better access to laterally extending osseous tumours originating from the second cervical vertebra. Using this approach, the lesion is manipulated from a strictly lateral direction parallel to a plane through the articular pillar of the CCJ and the odontoid process, and the C1- and C2-laminae are spared for posterior fixation. METHOD: The application of this approach is demonstrated in detail by an illustrative case of a chordoma originating from C2 that presented with intradural mass effect, considerable bone destruction, far-lateral extension to the right, and vertebral artery involvement. FINDINGS: The described approach gave ample access for total tumour resection. It allowed for safe control and displacement of the vertebral artery, spinal cord decompression, C2-corpectomy across the midline, and anterolateral bone reconstruction. No C1- or C2-hemilaminectomy was needed, and these bone elements could be used for posterior fixation (the patient presented in this study was referred to our institution after posterior fixation from the occiput to C3 had already been performed elsewhere). No intra-operative or postoperative complications occurred. At the 6-month follow-up, the patient was fully ambulatory with no neurological deficit. INTERPRETATION: The described lateral transfacetal route is the method of choice for operating on laterally extending osseous tumours originating from the second cervical vertebra.

Bone Transplantation↗

Horizontal fracture of the anterior arch of the atlas associated with a congenital cleft of the anterior arch.

We report a rare combination of a horizontal fracture of the anterior arch of the atlas associated with a congenital cleft of the anterior arch. Sagittally reformatted computed tomography (CT) images demonstrated a fracture of the anterior arch of the atlas and a type II odontoid process fracture. There was also a smoothly marginated midline cleft of the anterior arch just above the fracture consistent with a congenital variant. 3D CT images were helpful in the evaluation of the fractures and the developmental variant. Magnetic resonance imaging showed a spinal cord injury. The patient underwent posterior C1-C2 fusion.

Accidental Falls↗

The halo brace in unstable fractures of the cervical spine: a review of 14 cases.

A series of 14 patients with unstable fractures of the cervical spine, treated initially with skull traction and a few days later with a halo-thoracic brace, is described. Nine of the injuries were fractures of the odontoid process and the rest were at various levels. No patient with major neurological defects was included in the halo brace treatment. The halo brace provides significant advantages, including immediate mobilization with less time in hospital and less nursing. The results of the present series are encouraging; stable conditions were achieved in all cases.

Braces↗

Sagittal-plane mobility of the cat cervical spine.

The present study was conducted to evaluate the nature of sagittal-plane motion across cervical vertebral joints and to identify the centers of rotation for each joint in anaesthetized cats X-rayed in a range of head-neck postures. Relative positions of adjacent pairs of vertebrae were assessed by constructing transparent templates for each vertebra that could be overlaid onto different X-rays, and then by digitizing the locations of three markers attached at a distance from each template. The finite centers of rotation for each joint were estimated using a rigid-body method. The errors associated with the estimates were quantified further by using a method in which the positions of digitized markers were fitted to concentric circles using a least-squares approach. The center of rotation between the skull and C1 was located at the cranial articular facets between the two bones. The center of rotation between C1 and C2 was situated near the tip of the odontoid process close to the site of attachment of the transverse ligaments. Centers of rotation for the other cervical vertebral joints were located in the region of the intervertebral disc. A similar range of values was obtained for centers of rotation when extended or flexed postures were used for the calculations, suggesting that the centers of rotation may not move markedly throughout a range of sagittal-plane rotations of approximately 90 degrees at the skull-C1 joint and about 15-30 degrees at the other cervical joints. These results showed that all cervical joints rotated during sagittal-plane motion. A minimal representation of the musculoskeletal mechanics of the feline neck probably requires multiple segments, each corresponding to a single vertebral bone.

Animals↗

Morphogenesis of experimentally induced Arnold--Chiari malformation.

The administration of a single dose of vitamin A to pregnant hamsters, early during the morning of their 8th day of gestation, induces types I and II Arnold--Chiari malformation (ACM), as well as various types of axial skeletal-dysraphic disorders known to be associated with the human disease. This new model provides a means of carrying comparative studies between the axial skeletal defects and neurological anomalies of this complex developmental malformation with those which characterize the other induced disorders related to it. Study of this experimental model has demonstrated that the basichondrocranium of fetuses with ACM is shorter than normal and slightly elevated (lordotic) in relation to the axis of the vertebral column. The shortness of the basichondrocranium of these fetuses is caused by the underdevelopment of the occipital bone specially noticeable in its basal component (basioccipital). This basic defect has resulted in a short and small posterior cerebral fossa which is inadequate to contain the developing nervous structures of that region. The developing cerebellum is displaced downward to an anomalous position just above the foramen magnum; and, the developing medulla is compressed or crowded into the small posterior cerebral fossa of affected fetuses. The lordotic elevation of the basichondrocranium is also responsible for the reduction of the pontine flexure and the increased angle of the cervical flexure of the hindbrain found in these fetuses. All of these neurological anomalies, which are characteristic and diagnostic of clinical ACm as well, are considered here to be secondary to the axial skeletal defects rather than primary abnormalities, as is generally believed. The peculiar type of protrusion of the odontoid process into the cranial cavity found in fetuses with ACM, as well as in those with cranioschisis aperta and occulta, is also considered to be caused by the slight depression of the underdeveloped basioccipital and therefore, comparable to the so-called basilar impression often described in clinical ACM. This study has emphasized various developmental features which are closely related with the morphogenesis of ACM, including: the somitic origin of the occipital bone, and the late growth of the cerebellum which is predominantly postnatal in almost all experimental animals. It has been pointed out that some developmental defects involving the occipital bone and the caudal vertebral column, such as those which characterize ACM type II, may be more closely related than previously recognized. It has been also pointed out that the so-called cerebellar herniation into the cervical spinal canal described in the human disease represents a late addition to this disorder which is related to the relatively late growth of the cerebellum...

Animals↗