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. (+info)
Preliminary CT study of C1-C2 rotational mobility in normal subjects.
A CT study of normal atlanto-axial (C1-C2) rotary mobility was carried out on ten normal immature subjects. In order to determine the limits of normality, the ten children underwent clinical and radiological examination. The clinical study included checking for objective signs of joint laxity and measurement of rotational neck mobility. The radiological study included standard lateral radiographs in neutral and maximal flexion positions and a CT scan taken in maximal left and right side rotation at the C1-C2 articular processes joint. The superpositioning of the images taken in every rotational direction showed, in all ten children, a wide contact loss between the C1-C2 corresponding facets, ranging from 74 to 85% of the total articular surface. The report on these images, carried out by three independent radiologists, concluded that there was a rotary subluxation in all cases. In the ten children studied, there were no significant differences with regard to neck mobility or laxity signs in clinical or standard X-ray examination. Our results lead us to conclude that, except for complete C1-C2 rotational dislocation with facet interlocking, a CT scan showing a wide - but incomplete - rotational facet displacement is not sufficient to define a status of subluxation. This leads us to perceive that there is a risk of overdiagnosis when evaluating upper cervical spine rotational problems in children. The concept of both rotary C1-C2 fixation and subluxation should be revised. (+info)
Vertical atlantoaxial dislocation.
An unusual case of vertical atlantoaxial dislocation without medulla oblongata or spinal cord injury is reported. The pathogenic process suggested occipito-axial dislocation. The case was treated surgically with excellent results on mobility and pain. (+info)
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. (+info)
Transoral decompression for craniovertebral osseous anomalies: perioperative management dilemmas.
The surgical outcome of 74 patients, who underwent transoral decompression (TOD) for ventral irreducible craniovertebral junction anomalies between January 1989 to September 1997, was studied to evaluate the perioperative complications and problems encountered. The indications for TOD included irreducible atlantoaxial dislocation (n=24), basilar invagination (n=16), and a combination of both (n=35). Following TOD, occipitocervical stabilization using Jain's technique was carried out in 50 (67.5%) and atlantoaxial fusion using Brooks' construct in 18 (24.3%) patients. The pre- and postoperative radiology was compared to assess the adequacy of decompression and stability. The major morbidity included pharyngeal wound sepsis leading to dehiscence (20.3%) and haemorrhage (4%), valopharyngeal insufficiency (8.1%), CSF leak (6.7%) and inadequate decompression (6.7%). Neurological deterioration occurred transiently in 17 (22.9%) and was sustained in 7 (9.4%) patients. The mortality in six cases was due to operative trauma, exanguination from pharyngeal wound (one each), postoperative instability and inability to be weaned off from the ventilator (two each). Of the 47 (63.5%) patients available at follow up ranging from 3 months to 2 years, 26 (55.3%) showed improvement from their preoperative status while 14 (29.8%) demonstrated stabilization of their neurological deficits. Seven (14.9%) of them deteriorated. Though TOD is logical and effective in relieving ventral compression due to craniovertebral junction anomalies, it carries the formidable risks of instability, incomplete decompression, neurological deterioration, CSF leak, infection and palatopharyngeal dysfunction. (+info)
Stage-related surgery for cervical spine instability in rheumatoid arthritis.
Thirty-six consecutive patients with cervical spine instability due to rheumatoid arthritis (RA) were treated surgically according to a stage-related therapeutic concept. The aim of this study was to investigate the clinical results of these procedures. The initial change in RA of the cervical spine is atlanto-axial instability (AAI) due to incompetence of the cranio-cervical junction ligaments, followed by development of a peridontoid mass of granulation tissue. This results in inflammatory involvement of, and excessive dynamic forces on, the lateral masses of C1 and C2, leading to irreducible atlanto-axial kyphosis (AAK). Finally, cranial settling (CS) accompanied by subaxial subluxation (SAS) occurs. According to these three separate pathological and radiological lesions, the patients were divided into three therapeutic groups. Group I comprised 14 patients with isolated anterior AAI, who were treated by posterior wire fusion. Group II comprised 15 patients with irreducible AAK, who were treated by transoral odontoid resection. The fixation was done using anterior plating according to Harms in combination with posterior wire fusion according to Brooks. Group III comprised seven patients with CS and additional SAS, who were treated with occipito-cervical fusion. Pre- and postoperatively, evaluation was performed using the parameters pain (visual analog scale), range of motion (ROM), subjective improvement and Health Assessment Questionnaire (HAQ). The neurologic deficit was defined according to the classification proposed by Ranawat. Radiographs including lateral flexion and extension views, and MRI scans were obtained. The average clinical and radiographic follow-up of all patients was 50.7 +/- 19.3 months (range 21-96 months). No perioperative fatality occurred. Postoperative pain was significantly relieved in all groups (P < 0.001). In group II a slight improvement in the HAQ was obtained. In groups I and II the ROM of all patients increased significantly (average gain of motion in group I: 11.3 degrees +/- 7. 8 degrees for rotation; 7.8 degrees +/- 5.6 degrees for bending; average gain of motion in group II: 21.5 degrees +/- 14.0 degrees for rotation; 17.2 degrees +/- 5.5 degrees for bending), while it decreased significantly in group III (10.7 degrees +/- 18.1 degrees for rotation; 6.7 degrees +/- 18.5 degrees for bending). Preoperatively 27 patients had a manifest neurologic deficit. At follow-up four patients remained unchanged, all others improved by at least one Ranawat class. All patients, except one, showed solid bony fusion. According to the significantly improved postoperative subjective self-assessment and the clinical and radiological parameters, transoral plate fixation combined with posterior wire fixation after transoral odontoid resection represents an effective reliable and safe procedure for the treatment of irreducible AAK in rheumatoid arthritis. (+info)
Bow hunter's stroke associated with an aberrant course of the vertebral artery--case report.
A 53-year-old male presented with repeated vertebrobasilar insufficiency on turning the head to the left. Angiography revealed severe stenosis of the dominant right vertebral artery at the atlantoaxial level in this position. Decompression surgery for the affected vertebral artery at the transverse foramen of the atlas was planned. However, surgery revealed an aberrant course of the artery, turning at the orifice of the transverse foramen of the atlas and perforating the dura at the occipitoatlantal level after passing through the bony canal of the atlas. Therefore, decompression was performed at the bony canal, which was the contributing site, and the symptoms improved. Bow hunter's stroke may be caused by atlantoaxial arterial anomalies, so accurate preoperative evaluation of the region is necessary to avoid anatomical confusion at surgery. (+info)
Atlantoaxial dislocation associated with stenosis of canal at atlas.
Three rare cases of stenosis of spinal canal at the level of atlas associated with atlantoaxial dislocation are presented. An atlantoaxial lateral mass fixation with plate and screws after posterior midline bony decompression was successfully performed in these cases. (+info)