Electron transfer kinetics at a biotin/avidin patterned glassy carbon electrode

STUDY DESIGN: Comparison of findings in plain radiography and conventional tomography with findings in plain radiography and magnetic resonance imaging of the upper cervical spine in consecutive patients with rheumatoid arthritis and with known or suspected abnormalities of the cervical spine. OBJECTIVES: To determine whether plain radiography and magnetic resonance imaging provide enough information to dispense with tomography in investigations of cervical spine involvement in rheumatoid arthritis. SUMMARY OF BACKGROUND DATA: With the recent advances in magnetic resonance imaging technology and the proliferation of magnetic resonance imaging techniques for specific clinical conditions. METHODS: Twenty-eight patients with rheumatoid arthritis and with known or suspected abnormalities of the cervical spine underwent a clinical neurologic examination; plain radiography, including full flexion lateral radiography; anteroposterior and lateral tomography at C1-C2; and magnetic resonance imaging at the same level in neutral position and in flexion. Two radiologists evaluated one image set consisting of plain radiography and conventional tomographic images and another image set consisting of plain radiography and magnetic resonance images, for each patient. RESULTS: Compared with conventional tomography and plain radiography, magnetic resonance imaging and plain radiography showed cystic lesions and erosions of the odontoid process and vertical atlantoaxial subluxation more often, showed anterior subluxation as often, and showed lateral atlantoaxial subluxation less often. CONCLUSION: Magnetic resonance imaging produces sufficiently distinct images of destruction of the odontoid and subluxations for it to replace conventional tomography in investigations of upper cervical spine involvement in rheumatoid arthritis.     

Analysis of the IgG autoantibody repertoire in endocrine ophthalmopathy using the MegaBlot technique

The cervical spine is frequently involved in rheumatoid arthritis and yet there exists no consensus on the need to screen for cervical spine subluxations preoperatively. We reviewed retrospectively 77 patients who underwent 132 operations under general or regional anaesthesia over a 44-month period. We found that while the majority of patients had received preoperative X-ray screening for cervical spine instability, a third of the X-ray examinations done had been inadequate. Many anaesthetists did not repeat cervical spine X-rays if there were previously performed views available. We showed that a complete X-ray examination of the cervical spine should include flexion and extension stress views in addition to frontal views of the odontoid and entire cervical spine. Anterior atlantoaxial subluxation was the most common subluxation encountered in our study population. The detection of cervical spine instability was found to significantly affect anaesthetic management, favouring techniques that avoided unprotected manipulations of the neck under anaesthesia.     

Carcinogenic aspect of xenobiotic molecules belonging to the peroxisome proliferator family

STUDY DESIGN: Cervical motion patterns were analyzed in a normal population and in patients with cervical instability by using cineradiography. OBJECTIVES: To determine normal and pathologic motion patterns in the cervical spine through an in vivo continuous motion analysis. SUMMARY OF BACKGROUND DATA: Cineradiographic techniques have been used in a limited number of studies to quantify spinal motion. There is a paucity of information regarding dynamic motion patterns in normal and pathologic cervical spines. METHODS: Ten healthy subjects and 12 patients with unstable cervical spines (C1-C2 subluxation caused by rheumatoid arthritis, n = 10; instability below C2, n = 2) were studied. Cervical motion during flexion from the maximum extension position was recorded using cineradiography. Cervical segmental motions (C1-C2 to C5-C6) were continuously measured through quantifying cineradiographic images projected on a digitizer. RESULTS: Normal cervical spines showed a well-regulated stepwise motion pattern that initiated at C1-C2 and transmitted to the lower segments with time lags. Pathologic spines showed a different order of onset of segmental motion. In patients with rheumatoid arthritis who had atlantoaxial subluxation, C1-C2 motion initiated significantly earlier than C2-C3 motion. In patients with segmental instability below C2, motion in the unstable segments preceded that in the upper intact segments. CONCLUSIONS: Different motion patterns were observed between normal and pathologic cervical spines. Cineradiographic motion analysis is a valuable adjunctive technique, especially in diagnosis or evaluation of conditions that cannot be identified through conventional radiographic examination.     

Counterflow centrifugal elutriation: present and future

Only single cases with rheumatoid arthritis of the thoracic spine with vertebral subluxation have been reported to date. In a review of 100 patients with severe rheumatoid arthritis who had undergone occipitocervical fusion, arthritis of the upper thoracic spine with subluxation was discovered on conventional radiographs in four patients. Two additional patients were found elsewhere. Magnetic resonance imaging (MRI) was performed in three of the patients, confirming the diagnosis of subluxation of the upper thoracic vertebrae. In addition, MRI revealed encroachment on the anterior subarachnoid space and compression of the spinal cord.     

Multiple cerebellar infarction due to vertebral artery obstruction and bulbar symptoms associated with vertical subluxation and atlanto-occipital subluxation in ankylosing spondylitis

Ankylosing spondylitis (AS) results in disease-specific inflammation at the site of ligamentous insertion into the bone. Atlantoaxial joint subluxation and vertical subluxation of the axis may occur as a consequence of instability resulting from the inflammatory process. Spontaneous anterior atlantoaxial subluxation is a well recognized complication in about 2% of patients with AS, and presents with or without signs of spinal cord compression. Vertical subluxation may follow anterior or posterior subluxation. It was noted in 3-8% of patients with rheumatoid arthritis, but is an exceedingly rare complication of AS. Moreover, it has never been reported that multiple cerebellar infarction and bulbar symptoms developed spontaneously due to atlanto-occipital subluxation and vertical subluxation in a patient with a long [corrected] history of AS. We describe a man with AS who developed multiple cerebellar infarction due to vertebral artery obstruction and bulbar symptoms associated with atlanto-occipital subluxation and vertical subluxation.     

Surgery in the degenerative cervical spine

Degenerative changes of the cervical spine include changes of the bony and discoligamentous structures that can create mechanical alterations of the anatomy. Compressive syndromes and deformation or instability represent basic indications for surgery. In the upper cervical spine, osteoarthritis of the C1-C2 facet manifests with suboccipital pain syndrome caused by generally unilateral degenerative changes of the atlantoaxial facet. Fixation and atlantoaxial fusion represent the treatment of choice. In rare instances the presence of os odontoideum is responsible for atlantoaxial instability. Narrowing of the lateral recess in the subaxial spine produces radicular symptoms. The clinical symptoms should be supported with imaging methods such as computed tomography or magnetic resonance imaging. Selective decompression produces satisfactory results. Spondylotic cervical myelopathy requires the addition of neurophysiologic investigations. Posterior decompression with laminoplasty or anterior decompression procedures with corpectomy of the involved segments represent therapeutic options with comparable results. In the presence of axial neck pain, the exact location of the painful segment challenges clinicians and radiologists. Only in cases in which the clinical findings correlate with the radiologic changes should surgical fusion be considered as a last therapeutic means to resolve the painful condition.     

Surgery of the upper cervical spine in rheumatoid arthritis. Indications and results apropos of 28 cases

PURPOSE OF THE STUDY: The goal of this study was to precise indications and surgical techniques for stabilisation with or without decompression of the upper cervical spine instability in rheumatoid arthritis. MATERIAL AND METHODS: 28 patients presenting upper cervical spine disease have been reviewed (mean age 57 years). These patients had been suffering from severe diffuse arthritis during an average of 14.5 years. The anterior atlanto-axial dislocation was most frequent (25 times), 1 posterior dislocation and 2 vertical dislocations. Odontoid lysis was noted 19 times. A subluxation of the lower cervical spine was present in 12 patients. SURGICAL TECHNIQUE: C1-C2 arthrodesis was performed 12 times (9 times with a loop wire and 3 isthmo-pedicular screws C2-C1), occipito-cervical arthrodesis with plates 16 times. Operative traction was necessary 5 times. The associated surgical gestures included 3 times a laminectomy, 2 times an enlargement of the occipital foramen, 1 section of the Arnold nerve. In 2 patients was associated a fixation of the lower cervical spine. RESULTS: With an average of 27 months follow-up, functional results (classified according to Ranawat's criteria) were satisfactory in 14 patients, improved in 7 patients, unchanged in 4 and bad in 3. The reduction of the anterior displacement in 25 patients was complete 11 times, partial 17 times and null 3 times. The reduction of the vertical displacement was complete once, partial 3 times. Arthrodesis fusion was obtained in 19 cases, 5 times it was a fibrous union and 4 pseudarthrosis occurred, all with C1-C2 loop wire. The rate of complications was high: 2 infections on bone site grafting requiring reoperation, 2 infections with secondary septicemia after lack of reduction. DISCUSSION AND CONCLUSION: Occipito-cervical arthrodesis is necessary as soon as the patient presents neurological signs. When there is an anterior dislocation associated with vertical dislocation, if there is posterior dislocation in case of osteoporosis of the posterior C1-C2 arc, or destabilisation of the lower cervical spine. C1-C2 arthrodesis is suggested when there is no important neurological signs, when displacement is limited to a pure anterior dislocation and in young patient with good bone quality.     

Characteristics of ANP-binding sites in the adrenal capsules of term-pregnant rats

Magnetic resonance imaging (MRI) of the cervical spine was performed on 20 patients (mean age 10 years) with a preliminary diagnosis of juvenile rheumatoid arthritis (JRA). In all patients conventional x-rays of the cervical spine were obtained, and the relationship between clinical status and MRI findings were evaluated. Two patients with clinical manifestations, including neck pain and diminished range of motion, exhibited significant pathologic features on radiogram and MRI, the latter providing more detailed information. Among 18 patients who had no complaints about their cervical spines, 3 patients (65%) had either soft tissue involvement, pannus formation or erosions on the surface of atlantoaxial joints; only four patients (20%) had erosions on plain x-ray views. Since the early diagnostic ability of MRI in JRA allows early therapeutic intervention, every patient with a probable diagnosis of JRA would benefit from MRI.     

Quantifying serum antiplague antibody with a fiber-optic biosensor

Several studies of patients with chronic cervical pain and chronic whiplash syndrome report a high frequency of oculomotor function derangements pointing towards brainstem involvement and/or default sensory input from neck afferents. In light of these reports, it seems important to investigate other patient groups with similar upper cervical spine disorders. In this study, voluntary eye motor performance was evaluated in 11 rheumatoid patients (RA) with upper cervical dislocation and a clearly noticed joint affection of the cervical spine. The results were compared with 6 RA patients without cervical engagement and normal individuals. Nine of the 11 patients with atlanto-axial dislocation showed pronounced oculomotor disturbances of smooth pursuits compared with only minor changes in the control group. The pattern of oculomotor dysfunction in patients with rheumatoid cervical dislocation indicates brainstem involvement, which may be an early sign of brainstem affection/myelopathy.     

Work capacity of the upper limbs after mastectomy

A 59-year-old man presented with neck pain and limb numbness. He also had bilateral symmetrical joint deformities of his hands and wrists. Cervical spine radiographs showed C 1/2 instability and features of rheumatoid arthritis. Magnetic resonance imaging demonstrated erosion ofthe odontoid peg by pannus. C 1/2 surgical fusion was performed. The role of imaging in cervical spine involvement by rheumatoid arthritis is reviewed.     

Exacerbated pain in cervical radiculopathy at axial rotation, flexion, extension, and coupled motions of the cervical spine: evaluation by kinematic magnetic resonance imaging

RATIONALE AND OBJECTIVES: The authors evaluate the functional changes in patients with cervical radiculopathy and increasing symptoms after provocative maneuvers at flexion, extension, axial rotation, and coupled motions of the cervical spine. METHODS: Twenty-one patients with cervical disc herniation (n = 17) or cervical spondylosis (n = 4) in whom symptoms were elicited at flexion, extension, axial rotation, and coupled motions of the cervical spine were studied. The patients were examined inside a positioning device by using a circular surface coil for signal reception. At neutral position (0 degrees) and at provocative positions sagittal T2-weighted turbo spin-echo, axial T2-weighted two-dimensional flash sequence, sagittal three-dimensional (3D) fast imaging with steady state precision sequence and coronal 3D double-echo-in-the-steady-state sequences were obtained. The 3D sequences were reformatted in the axial and oblique coronal planes perpendicular to the exiting nerve roots. The images were evaluated for the size of disc herniations, the foraminal size and cervical cord rotation or displacement at provocative position compared with neutral position (0 degrees). RESULTS: Compared with neutral position (0 degrees), change in size of disc herniation was not found in any (0%) of the provocative positions. In five (24%) patients cervical cord rotation or displacement was noted at axial rotation. The foraminal size increased at flexion, axial rotation to the opposite side of pain and flexion combined with axial rotation to the opposite side of the pain. The foraminal size decreased at extension combined with axial rotation to the side of the pain. A decrease or no change in foraminal size was observed at either extension or axial rotation to the side of the pain. CONCLUSIONS: In patients with cervical disc herniation or cervical spondylosis, exacerbated pain at defined provocative maneuvers is related more to changes in the foraminal size and to nerve root motion with, in some cases, cervical cord rotation or displacement than to changes in the size of herniated discs.     

The effect of triple pelvic osteotomy on the articular contact area of the hip joint in dysplastic dogs: an in vitro experimental study

This study compares the frequency of signs and symptoms from the cervical spine in 24 patients diagnosed with Meniere's disease and 24 control subjects from a population sample. From a previous controlled comparative study concerning signs and symptoms of craniomandibular disorders, 24 patients diagnosed with Meniere's disease (10 males and 14 females) and their 24 matched control subjects participated in this investigation on the state of the cervical spine. Symptoms of cervical spine disorders, such as head and neck/shoulder pain, were all significantly more frequent in the patient group than in the control group. Most of the patients (75%) reported a strong association between head neck movements in the atlanto-occipital and atlanto-axial joints and triggered attacks of vertigo. Also, 29% of the patients could influence their tinnitus by mandibular movements. Signs of cervical spine disorders, such as limitations in side-bending and rotation movements, were significantly more frequent in the patient group than in the control group. Tenderness to palpation of the transverse processes of the atlas and the axis, the upper and middle trapezius, and the levator scapulae muscle were also significantly more frequent in the patient group. The study shows a much higher prevalence of signs and symptoms of cervical spine disorders in patients diagnosed with Meniere's disease compared with control subjects from the general population.     

3- to 11-year followup of occipitocervical fusion for rheumatoid arthritis

The relief of myelopathy usually is unsatisfactory by a conventional Gallie type atlantoaxial fusion for patients with rheumatoid arthritis who have irreducible atlantoaxial dislocation. To accomplish a decompressive laminectomy of the atlas in the treatment of myelopathy, the authors have been performing a new surgical procedure since 1985 for occipitocervical fusion using a rectangular rod. The postoperative outcomes for 25 patients with rheumatoid arthritis were evaluated clinically and radiographically with a 3- to 11-year (mean, 6.5 years) followup. A decompressive laminectomy of the atlas accompanied the fusion in 21 of the 25 patients. The incidence of occipital or nuchal pains improved notably in most cases, and myelopathy was relieved in 12 of 18 (67%) cases, showing an improvement of more than one level based on Ranawat's criteria. No serious postoperative complications were seen, except for one case of a failed bone union. The cumulative survival in patients with myelopathy was 79.4% in the first 5 years after operation and 27.5% at 10 years. Occipitocervical fusion using a rectangular rod accompanied by a decompressive laminectomy of the atlas can contribute to the relief of a neurologic deficit in an irreducible atlantoaxial dislocation in rheumatoid arthritis.     

Rheumatoid arthritis and vertebral artery occlusion: a case report with angiographic and magnetic resonance demonstration

A 40-year-old woman with rheumatoid arthritis (RA) who presented with vertigo and nausea, was found to have left vertebral artery occlusion on angiography. There was minimal atlantoaxial subluxation and no odontoid herniation. Magnetic resonance imaging (MRI) was suggestive of a left vertebral artery dissection. This is the first report of MRI of vertebral artery occlusion in RA. It will be important to accumulate MR images of this complication in future cases.     

The use of bedside fluoroscopy to evaluate the cervical spine in obtunded trauma patients

BACKGROUND: Recognition of a cervical spine injury is important to prevent further injury and in planning for future care. The management of the patient with a possible cervical spine injury who remains unresponsive is controversial. METHODS: A retrospective evaluation of obtunded trauma patients admitted to the surgical intensive care unit who underwent bedside fluoroscopic cervical spine evaluation. Fluoroscopic findings and all complications were noted. RESULTS: Twenty obtunded patients with possible cervical spine injuries underwent bedside fluoroscopic cervical spine evaluation. All patients had at minimum a normal three-view cervical spine series before fluoroscopy. Thirteen patients (65%) had the fluoroscopic examination completed at the bedside and were cleared. The complete cervical spine could not be evaluated in six patients (30%). One patient (5%) was found to have a C4-5 subluxation in the bedside examination. None of the patients had progression of their neurologic symptoms after cervical spine flexion/extension, and none developed evidence of spinal cord injury after being cleared during their hospital course. Cervical collars remained in place for 5.7+/-1.41 days (range, 1- 26 days). Three patients (15%) were noted to have decubiti under the cervical collar. CONCLUSION: In this small study, the use of bedside fluoroscopy to evaluate the cervical spine appears safe and easy to perform. One unrecognized injury was identified. The technique is usually successful and gives reassurance that a significant cervical spine injury is not present.     

Hangman's fracture: arguments in favor of surgical therapy for type II and III according to Edwards and Levine

BACKGROUND: The optimal therapy for traumatic fractures of the neural arch of the axis, the so-called hangman's fractures, is still controversial. Indications for surgery depend on the type of hangman's fracture and/or additional injuries of the intervertebral disc or ligaments. METHODS: Sixteen patients sustaining fractures of the neural arch of the axis were treated by the screw fixation technique evolved by Judet. The passive mobility of the cervical spine was analyzed postoperatively by the radiographic evaluation method of Dvorak and coworkers and Penning. The angulation and anterior translation of C2 on C3 was measured before and after surgery. RESULTS: Follow-up investigations 3, 12, and in some cases 45 months later confirmed sufficient functional results especially regarding the mobility of the upper cervical spine. Comparison of pre- and postoperative angulation and anterior translation of C2 on C3 revealed a significant improvement especially in cases with type IIa fractures. CONCLUSION: The stabilization technique of Judet facilitates an exact reconstruction of anatomical conditions thereby preserving the atlantoaxial rotational mobility. A negligible hypomobility of the C2-C3 segment was observed on average 18 months after surgery.     

Sleep apnoea caused by rheumatoid arthritis

Sleep apnoea syndrome (SAS) is a rarely documented, but possibly lethal, complication of the instability of the cervical spine in rheumatoid arthritis. Five patients with SAS of a central or peripheral origin are presented, and the problems of recognizing and diagnosing the syndrome are discussed. We hope that clinicians will become more aware of the existence and the different aetiologies of SAS, thus improving early recognition and appropriate treatment. Adequate treatment has proven to increase survival in peripheral SAS and seems to be successful in doing so in central SAS.     

Somatosensory evoked potentials in rheumatoid polyarthritis with radiologic involvement of the cervical spine

Somatosensory evoked potentials (SEP) have been recorded in 11 patients with cervical spine involvement, with or without signs of myelopathy due to rheumatoid arthritis (RA). In three patients, SEP have been recorded both before and after cervical spine surgery. In seven cases, the P14 (particularly the P9/P14 amplitude ratio) or P30 potentials were abnormal, whereas other potentials and conduction times were less often modified. Vertebral luxation sites that were predominantly observed at the upper cervical level account for these findings, thus supporting the diagnostic utility of P14 and P30 potentials which respectively take origin in the lower brain stem, close to or into the nuclei cuneatus and gracilis. Postoperative SEP were strongly correlated with the surgical outcome. SEP could be abnormal in the absence of overt clinical myelopathy or vertebral luxations, thus revealing infraclinical damage to the somatosensory pathways. This suggests that SEP recording is useful to discriminate RA patients with upper cervical cord dysfunction from those in whom vertebral lesion proves to have no direct impact on somatosensory conduction.     

Physiological changes in insulin resistance in human pregnancy: longitudinal study with the hyperinsulinaemic euglycaemic clamp technique

Twenty-six patients with rheumatoid disease affecting the cervical spine underwent surgical treatment for neck pain, neurological deficit, or both. Atlantoaxial subluxation (n=13), subaxial subluxation (n=7) and vertical migration of the odontoid (n=6) were treated. Arthrodesis with autologous bone was augmented with wire, Ransford loop, Hartshill rectangle or Magerl technique. Pain relief occurred in 92% of patients. Neurological deficit improved in 89% and was unchanged in the remainder. Radiographic stability was achieved in all but one patient. Posterior surgery effectively relieved pain and neurological deficit, and the complications encountered did not jeopardize the outcome.     

Occipital calvarial bone graft in posterior occipitocervical fusion

STUDY DESIGN: Dorsal occipitocervical fusion is associated with a high rate of fusion failure and requires an additional surgical site for donor bone graft harvesting. In this series, an autologous occipital calvarial bone graft obtained from the same occipitocervical incision with contoured metal loops was used in 25 adults to achieve craniovertebral stabilization and fusion. OBJECTIVES: To study the use of autologous occipital calvarial bone grafts in occipitocervical fusion. SUMMARY OF BACKGROUND DATA: Cranial bone grafts have been used successfully in craniofacial reconstruction with good long-term results. In the plastic surgery literature, there are claims that membranous bone grafts are superior to endochondral bone grafts in fusions because of decreased resorption. In recent studies, results have shown successful use of calvarial bone in fusing the upper cervical spine in children. The use of autologous occipital bone in posterior occipitocervical fusions avoids many of the problems associated with traditional donor sites and provides a sufficient quantity of good quality bone for the fusion. This is especially true in the fragile rheumatoid arthritis patient with cranial cervical instability. METHOD: Split-thickness, autologous calvarial bone grafts with contoured loop and cable instrumentation were used for posterior occipitocervical stabilization and fusion in 25 patients, most of whom had rheumatoid arthritis. The calvarial bone graft was harvested from the occipital skull, using a microair impactor, and was secured next to the loop construct. After surgery, all patients were immobilized with external orthoses. RESULTS: None of the patients had hardware failure or complications from the occipital graft procurement. In 22 patients, good alignment, stability, and bony fusion were shown on radiographs. CONCLUSIONS: Occipital calvarial bone graft appears to work as well as other autologous corticocancellous bone grafts routinely used in posterior occipitocervical fusions.