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At least 1,009 records · Page 56Linked to original sources
PubMed1999

The extent of drilling in lateral approaches to the cranio-cervical junction area from a series of 125 cases.

The trans-condylar approach to the craniocervical junction area (CCJA) requires a more or less extensive drilling of the two first cervical joints (C0-C1 and C1-C2). The extent of drilling necessary to resect a lesion at the CCJA was analyzed from a series of 125 cases including 114 tumours and 11 non-tumoural processes treated using a lateral approach (postero-lateral or antero-lateral) over a 15-year period (1980-1995). The extent of drilling was estimated on CT scanner axial views from the reduction of the joints surface and three groups were determined: A/less than one third B/between one third and one half, and C/more than one half. The extent of drilling was compared with the lesion location in relation to the bone limits of the CCJA: within these limits, outside them and into the bony structures. It was also analyzed with regard to pathology when separated into three groups non-osseous tumours, osseous tumours and chordomas, and non tumoural processes. Only 26 cases had a significant drilling, i.e., more than one third of the joint surfaces and of these, 14 were more than one half. In all these 14 cases, the bone structures were already invaded and 13 of them were, to some extent, beyond the bone limits of the CCJA. Of the 12 cases with drilling between one third and one half, 11 involved the bone structures and 1 was located inside the CCJA bone limits. Drilling of more than one third was required only in the case of bone lesions: 10 out of 23 bone tumours, all the 14 cases of chordomas, one case of rheumatoid arthritis and one case of C1-C2 joint spondylosis. In the other cases including mostly non-osseous tumours, drilling was limited to less than one third, though a high rate of complete removal was achieved (98%). Stabilization by arthrodesis with posterior grafting (N = 10) or by lateral bone grafting (N = 5) was achieved in all cases involving more than one half drilling, and in one case of tuberculosis. By adequately choosing the surgical approach, the extent of drilling can always be minimal. Extensive bone resection is only necessary when the tumour has already destroyed the joints. In that case, lateral or posterior fusion is an efficient technique.

Axis, Cervical Vertebra↗
PubMed2006

Intraoperative dynamic angiography to detect resolution of Bow Hunter's syndrome: Technical case report.

BACKGROUND: Bow Hunter's syndrome is a rare form of vertebrobasilar insufficiency that may be successfully treated by surgical intervention. Use of intraoperative dynamic transcranial Doppler ultrasound for surgical treatment of vertebrobasilar insufficiency has been described in literature. However, this technique was inconsistent and unreliable in some patients. We present a case of a patient with Bow Hunter's syndrome treated surgically and emphasize the valuable addition of intraoperative dynamic angiography to determine resolution of vertebral artery compromise. CASE DESCRIPTION: The patient was a 58-year-old man with complaints of dizziness, vertigo, and near-syncopal episodes that occurred when he rotated his head to the left. Imaging revealed compromise of the dominant left vertebral artery with leftward head rotation. An anterior cervical approach with decompression of the left subaxial vertebral artery was performed. Significant osteophyte formation was observed. Removal of bone and decompression of the vertebral artery was performed. Intraoperative dynamic angiography confirmed resolution of vertebral artery compression and minimized the amount of decompression. No further intervention was required. CONCLUSION: Intraoperative dynamic angiography is a definitive test to determine hemodynamic resolution of Bow Hunter's syndrome. It offers real-time feedback of vertebral artery decompression, potentially minimizes the amount of decompression, and can be performed safely.

Axis, Cervical Vertebra↗
PubMed2001

Modified Brooks posterior wiring technique for three-point C1-C2 arthrodesis.

BACKGROUND: The optimal surgical treatment of atlanto-axial instability remains controversial despite the variety of modifications and supplemental techniques currently available. METHODS: We describe a modification of the Brooks posterior wiring technique supplemented with transarticular screws for C1-C2 instability. RESULTS: This method has been implemented in 30 patients in our institution with no radiological failures. CONCLUSIONS: The modification provides several technical advantages and potentially stronger fixation compared to methods currently in use.

Axis, Cervical Vertebra↗
PubMedDate not supplied

[Transaxial spongiosa-plasty and ventral, temporary atlanto-axial fixation for therapy of dens pseudarthrosis].

PURPOSE: According to literature there is a pseudarthrosis rate of about 1% up to 64% depending on the treatment of the dens fracture (16). Generally the treatment of dens pseudarthrosis consists of the fusion of the joint C1/C2 with or without dens resection. Now, a method is presented whereby, on the one hand the pseudarthrosis is treated, while on the other hand the anatomical structures and physiological function of the joint C1/ C2 are restored. METHOD: The operation consists of a gradual outboring of the base of the dens and the dens axis and filling with autologous cancellous bone. Then follows a lateral, temporary transarticular screw fixation of C1/C2 which guarantees an immobilisation of the filled out dens. A halo-body-jacket is then applied. The removal of the screws of the temporary fixation follows three months post operatively after X-ray control. Then physiotherapy of the cervical spine follows. RESULTS: During 7/93 and 7/97 this operation was carried out on 11 patients. In 9 cases compression screw osteosynthesis was primarily conducted and in 2 cases conservative therapy had preceded. The X-ray follow ups showed on an average of 14 month a stable bony fusion in 10 patients, the clinical follow up examinations on an average of 14 month a normal function. CONCLUSION: The operation presented is indicated in case of dens pseudarthrosis because this accomplished a definite bony fusion without disturbance of the function of the joint C1/C2 in patients not older than 60 years. Disadvantages are to be found in the intraoperatively high X-ray radiation and the 3 month immobilisation.

Adolescent↗
PubMed1998

Anatomic study for ideal and safe posterior C1-C2 transarticular screw fixation.

STUDY DESIGN: Directions of the C1-C2 posterior transarticular screw trajectories making the longest path or violating the transverse foramen were measured by using an objective measuring method. OBJECTIVES: To clarify the directions of the screw trajectory marking the longest paths without violating the transverse foramen. To achieve this, diverse directions of the screw trajectories were objectified by measuring the locations of the points of screw intersection on the superior articular surface of C2. SUMMARY OF BACKGROUND DATA: The principal limitation of posterior C1-C2 transarticular screw fixation is the location of the vertebral artery. Because of the lack of an objective measuring method, surgical unsuitability has been decided on the basis of individual experiences as reported in 18% to 23% of cases. METHODS: Sagittal reconstructed computed tomographic images were made at 3.5 mm and 6 mm from the spinal canal. C1-C2 transarticular screw trajectories making the longest path or violating the transverse foramen (dangerous trajectory) were drawn, and their points of screw intersection on the superior articular surface of C2 were measured from the posterior rim of the superior articular surface of C2. When the space available for the screw behind the points of screw intersection by the dangerous trajectory was equal to or less than 3.5 mm, the case was defined as "unacceptable"; when the space available for the screw was more than 3.5 mm but equal to or less than 4.5 mm, it was defined as "risky" for the placement of the screw. RESULTS: Trajectories make the longest paths when they pass an average of 3.6 mm and 2.8 mm anterior to the posterior rim of the posterior articular surface of C2 at 3.5-mm lateral images and 6-mm lateral images, respectively. Four of 64 cases were unacceptable or risky unilaterally on 3.5-mm lateral images, and 21 cases were unacceptable or risky on 6-mm lateral images. A sigmoid-shaped increment curve of the risk was noted as the increasing forward inclination of the screw trajectories increased. CONCLUSIONS: The areas on the superior articular surface of C2 intersected by the trajectories making the longest paths without violating the transverse foramen are clarified as a guide to the ideal and safe trajectories. The theoretical minimal risk and usual risk of the posterior C1-C2 transarticular screw fixation are presented as well.

Adult↗
PubMed2000

Modification of C1-C2 transarticular screw fixation by image-guided surgery.

STUDY DESIGN: This is a feasibility study of image-guided surgery for C1-C2 transarticular screw fixation comparing postoperative screw position in a nonrandomized prospective cohort with a historic control group in which fluoroscopic guidance was used alone. OBJECTIVES: To evaluate the potential benefits and disadvantages of image-guided surgery for C1-C2 screw placement. SUMMARY OF BACKGROUND DATA: C1-C2 transarticular screw fixation is biomechanically superior to other current surgical stabilization procedures. The original technique for C1-C2 screw placement relies on anatomic landmarks and intraoperative fluoroscopy. Screw misplacement or anatomic variations can result in vertebral artery injury. Image-guided surgery involves using computed tomography (CT) data to plan the optimal screw trajectory before surgery and then use this data to guide screw placement during the actual surgery. Promising results of this technique are reported in the literature, but no direct comparison between image-guided surgery and conventional surgical techniques has been previously reported. METHODS: The image-guided surgery group consisted of 37 prospective patients. The historic control group included 78 patients who had similar surgeries performed using only fluoroscopic guidance. For the image-guided surgery group, subluxation was reduced by positioning at the time of CT examination. The CT data were transferred to a StealthStation (Sofamor-Danek, Memphis, TN) surgical planning and guidance computer system, and an optimal screw trajectory was determined for the right and left transarticular screws. After matching the surgical field to the virtual computer field, C2 was drilled according to the planned screw trajectory, and screws were placed. Plain radiographs and CT were used for postoperative evaluation of the image-guided surgery group. RESULTS: Image-guided surgery reduced but did not eliminate the risk of screw misplacement. Surgical time was not increased overall. CONCLUSIONS: Image-guided surgery is an effective tool for the achievement of correct screw placement in C1-C2 transarticular screw fixation procedures. The procedure remains technically demanding.

Axis, Cervical Vertebra↗
PubMed2005

Frameless stereotactic image-guided C1-C2 transarticular screw fixation for atlantoaxial instability: review of 20 patients.

OBJECTIVE: We retrospectively studied 20 adults who underwent C1-C2 transarticular screw (TAS) fixation utilizing frameless stereotaxy. METHODS: The study group comprised 13 men and 7 women, with a mean age of 63 years (range 12-87 years). All patients demonstrated clinical and radiographic evidence of C1-C2 instability. The cause of the instability was trauma in 11 patients, rheumatoid arthritis in 6 patients, failed prior surgery in 2 patients, and congenital malformation in 1 patient. All patients underwent stabilization with C1-C2 TASs using image-guided frameless stereotaxy. RESULTS: There were no new or worsening neurologic symptoms reported at 18-month follow-up. Motor weakness improved in seven of nine patients, myelopathy in seven of seven, and gait in three of six patients in whom these deficits were present preoperatively. Postoperative complications included one surgical site abscess, one cutaneous pressure ulcer, and one iliac crest donor site infection. Of 36 screws placed, 33 (92%) were well positioned. Normal C1-C2 alignment was achieved in 17 of 20 (85%) patients. In 4 of 20 cases, screw implant, which was thought to be anatomically difficult, if not impossible, on the basis of routine magnetic resonance or computed tomography imaging, was actually accomplished successfully using surgical navigation. CONCLUSIONS: C1-C2 TAS placement is a safe and accurate surgical technique that may improve neurologic function. Use of intraoperative navigation can facilitate achieving difficult surgical trajectories that match the patient's anatomy, thus allowing TAS implant in patients who otherwise would not be candidates for this type of internal fixation.

Adolescent↗
PubMed1976

Vertebrobasilar artery insufficiency in rheumatoid atlantoaxial subluxation.

Cervical myelopathy has become commonly recognized as a complication of rheumatoid atlantoaxial subluxation. A small group of patients with atlantoaxial subluxation may have intermittent symptoms associated with change of head position and which are due to vertebral artery compression. Two such cases are reported, one with necropsy findings of infarction in the area supplied by the vertebrobasilar system. The pathogenesis of the symptomatology and infarction is discussed.

Aged↗
PubMed1995

Substantial head trauma: value of routine CT examination of the cervicocranium.

PURPOSE: To evaluate the usefulness of routine performance of computed tomography (CT) of the craniocervical junction in unconscious patients with substantial head injury. MATERIALS AND METHODS: In a prospective study, CT of the head and the cervicocranium was performed in 202 patients with substantial cranial trauma (Glasgow Coma Scale scores of 3-6). Plain radiography was performed in all patients. Radiographs and CT scans were then blindly interpreted. RESULTS: Twenty-eight patients (13.9%) had C-1 or C-2 fractures; plain radiographs did not demonstrate cervical fractures in 11 of these patients. Nine patients (4.4%) had fractures of the occipital condyles; plain radiographs did not demonstrate occipital condyle fractures in eight of these patients. CONCLUSION: Because 5.4% of all patients had fractures of either C-1 or C-2 and 4.0% had occipital condyle fractures not seen at plain radiography, routine additional performance of CT of the craniocervical junction is useful in patients with substantial cranial trauma.

Adolescent↗
PubMed2005

Rotational vertebral artery syndrome: oculographic analysis of nystagmus.

In four patients with rotational vertebral artery syndrome (RVAS), the initial nystagmus was mostly downbeat, with the horizontal and torsional components beating toward the compressed vertebral artery side (n = 3) or directed away (n = 1). Three patients showed spontaneous reversal of the nystagmus and two exhibited no or markedly diminished responses on immediate retrial of head rotation (habituation). The patterns of nystagmus suggest that RVAS may result from differing mechanisms.

Aged↗