bluuebunny/crossref_metadata_2025_split huggingface dataset:
An alternate method for placement of C-1 screws
Authors: Thomas J. Alex , Tredway Trent , Fessler Richard G. , Sandhu Faheem A. 
Published: February 2011

Object
Several techniques for the surgical stabilization of the atlas and the axis have been described. Placement of C-1 lateral mass screws is one of the latest technical advances, and has gained popularity due to its efficacy and biomechanical advantages. However, the technique for placement of C-1 lateral mass screws, as first described by Harms, can cause excessive bleeding or irritation of the C-2 nerve. An alternative technique is available for the placement of C-1 lateral mass screws that completely avoids the C-2 nerve/ganglion and its associated venous plexus. This new technique mitigates some of the risk associated with the Harms techniques and eliminates the need to use specialized screws (that is, smooth shanks).

Methods
Twenty-six patients underwent atlantoaxial or occipitocervical fusions incorporating the alternative technique of C-1 screw placement. Three surgeons at 3 different institutions performed the surgeries. Standard lateral fluoroscopy and fully threaded polyaxial screws were used in each case.

Results
Forty-nine screws were placed in C-1 lateral masses by using the new technique. Solid arthrodesis was achieved in all cases, with a mean follow-up period of 30 months. There were no cases of CSF leakage, new neurological deficit, injury to the C-2 ganglion, vertebral artery injury, or hardware failures.

Conclusions
The technique is a safe and effective way to fixate C-1 while avoiding the C-2 nerve/ganglion and venous plexus. The results indicate that excellent clinical and radiographic outcomes can be achieved with this new technique.
Effects of age on perioperative complications of extensive multilevel thoracolumbar spinal fusion surgery
Authors: Cloyd Jordan M. , Acosta Frank L. , Cloyd Colleen , Ames Christopher P. 
Published: February 2011

Object
The elderly compose a substantial proportion of patients presenting with complex spinal pathology. Several recent studies have suggested that fusion of 4 or more levels increases the risk of perioperative complications in elderly patients. Therefore, the purpose of this study was to analyze the effects of age in persons undergoing multilevel (≥ 5 levels) thoracolumbar fusion surgery.

Methods
A retrospective review of all hospital records, operative reports, and clinic notes was conducted for 124 consecutive patients who underwent surgery between 2000 and 2007 with an average follow-up of 3.5 years and a minimum follow-up of 1.2 years. The most frequent preoperative diagnoses included scoliosis, tumor, osteomyelitis, vertebral fracture, and degenerative disc disease with stenosis. Complications were classified as intraoperative and major and minor postoperative as well as the need for revision surgery. Multivariate logistic regression analysis was used to determine the effects of age and other potentially prognostic factors.

Results
After controlling for other factors, increasing age was associated with an elevated risk for major postoperative complications (OR 1.04, 95% CI 1.00–1.10) as were increasing levels of fusion (OR 1.5, 95% CI 1.1–2.1) and male sex (OR 4.6, 95% CI 1.3–16.2). In patients 65 years of age or older, rates of intraoperative complications, major and minor postoperative complications, and reoperation were 14.1, 23.4, 29.7, and 26.6%, respectively. The number of comorbidities was associated with a greater risk for perioperative complications in elderly patients (OR 1.8, 95% CI 1.1–2.8).

Conclusions
Age is a positive risk factor for major postoperative complications in extensive thoracolumbar spinal fusion surgery. Complication rates in the elderly are high, and good clinical judgment and careful patient selection are needed before performing extensive thoracolumbar reconstruction in older persons.
Using magnetic resonance imaging to accurately assess injury to the posterior ligamentous complex of the spine: a prospective comparison of the surgeon and radiologist
Authors: Rihn Jeffrey A. , Yang Nuo , Fisher Charles , Saravanja Davor , Smith Harvey , Morrison William B. , Harrop James , Vacaro Alexander R. 
Published: February 2011

ObjectMagnetic resonance imaging has been proposed as a powerful technique for assessing the integrity of the posterior ligamentous complex (PLC) in spinal trauma. Because MR imaging is often used to determine appropriate treatment, it is important to determine the accuracy and reliability of MR imaging in diagnosing PLC disruption. The purpose of this study is to compare the ability of the radiologist and surgeon to assess disruption of the PLC in the setting of acute cervical and thoracolumbar trauma using MR imaging.MethodsThe components of the PLC in 89 consecutive patients with cervical or thoracolumbar fractures following acute spinal trauma were evaluated using MR imaging by both a musculoskeletal radiologist and an independent spine surgeon and assessed intraoperatively under direct visualization by the treating surgeon. The MR imaging interpretations of the musculoskeletal radiologist and surgeon were compared with the intraoperative report for accuracy, sensitivity, specificity, and positive and negative predictive values. A comparison between the radiologist's and spine surgeon's accuracy of MR imaging interpretation was performed.ResultsThe agreement between both the spine surgeon's and radiologist's MR imaging interpretation and the actual intraoperative findings was moderate for most components of the PLC. Overall, the MR imaging interpretation of the surgeon was more accurate than that of the radiologist. The interpretation of MR imaging by the surgeon had negative predictive value and sensitivity of up to 100%. However, the specificity of MR imaging for both the surgeon and radiologist was lower, ranging from 51.5 to 80.5%.ConclusionsComparison of the MR imaging interpretations between surgeon and radiologist indicates that the surgeon was more accurate for some PLC components. The relatively low positive predictive value and specificity for MR imaging in assessing PLC integrity suggests that both the surgeon and radiologist tend to overdiagnose PLC injury using MR imaging. This can lead to unnecessary surgeries if only MR imaging is used for treatment decision making.
Setup accuracy of spine radiosurgery using cone beam computed tomography image guidance in patients with spinal implants
Authors: Gerszten Peter C. , Monaco Edward A. , Quader Mubina , Novotny Josef , Kim Jong Oh , Flickinger John C. , Huq M. Saiful 
Published: February 2011

Object
Cone beam computed tomography (CBCT) image guidance technology has been adopted for use in spine radiosurgery. There is concern regarding the ability to safely and accurately perform spine radiosurgery without the use of implanted fiducials for image guidance in postsurgical cases in which titanium instrumentation and/or methylmethacrylate (MMA) has been implanted. In this study the authors prospectively evaluated the accuracy of the patient setup for spine radiosurgery by using CBCT image guidance in the context of orthopedic hardware at the site of disease.

Methods
The positioning deviations of 31 single-fraction spine radiosurgery treatments in patients with spinal implants were prospectively evaluated using the Elekta Synergy S 6-MV linear accelerator with a beam modulator and CBCT image guidance combined with a robotic couch that allows positioning correction in 3 translational and 3 rotational directions. To measure patient movement, 3 quality-assurance CBCT studies were performed and recorded: before, halfway through, and after radiosurgical treatment. The positioning data and fused images of planning CTs and CBCTs from the treatments were analyzed to determine intrafractional patient movements. From each of 3 CBCTs, 3 translational and 3 rotational coordinates were obtained.

Results
The prescribed dose to the gross tumor volume for the cohort was 12–18 Gy (mean 14 Gy) utilizing 9–14 coplanar intensity-modulated radiation therapy (IMRT) beams (mean 10 beams). At the halfway point of the radiosurgery, the translational variations and standard deviations were 0.6 ± 0.6, 0.4 ± 0.4, and 0.5 ± 0.5 mm in the lateral (X), longitudinal (Y), and anteroposterior (Z) directions, respectively. The magnitude of the 3D vector (X,Y,Z) was 1.1 ± 0.7 mm. Similarly, the variations immediately after treatment were 0.5 ± 0.3, 0.4 ± 0.4, and 0.5 ± 0.6 mm along the X, Y, and Z directions, respectively. The 3D vector was 1.0 ± 0.6 mm. The mean rotational angles were 0.3 ± 0.4, 0.5 ± 0.6, and 0.3 ± 0.4° along yaw, roll, and pitch, respectively, at the halfway point and 0.3 ± 0.4, 0.6 ± 0.6, and 0.4 ± 0.5° immediately after treatment.

Conclusions
Cone beam CT image guidance used for patient setup for spine radiosurgery was highly accurate despite the presence of spinal instrumentation and/or MMA at the level of the target volume. The presence of such spinal implants does not preclude safe treatment via spine radiosurgery in these patients.
Biomechanics of a lumbar interspinous anchor with anterior lumbar interbody fusion
Authors: Karahalios Dean G. , Kaibara Taro , Porter Randall W. , Kakarla Udaya K. , Reyes Phillip M. , Baaj Ali A. , Yaqoobi Ali S. , Crawford Neil R. 
Published: February 2011

Object
An interspinous anchor (ISA) provides fixation to the lumbar spine to facilitate fusion. The biomechanical stability provided by the Aspen ISA was studied in applications utilizing an anterior lumbar interbody fusion (ALIF) construct.

Methods
Seven human cadaveric L3–S1 specimens were tested in the following states: 1) intact; 2) after placing an ISA at L4–5; 3) after ALIF with an ISA; 4) after ALIF with an ISA and anterior screw/plate fixation system; 5) after removing the ISA (ALIF with plate only); 6) after removing the plate (ALIF only); and 7) after applying bilateral pedicle screws and rods. Pure moments (7.5 Nm maximum) were applied in flexion and extension, lateral bending, and axial rotation while recording angular motion optoelectronically. Changes in angulation as well as foraminal height were also measured.

Results
All instrumentation variances except ALIF alone reduced angular range of motion (ROM) significantly from normal in all directions of loading. The ISA was most effective in limiting flexion and extension (25% of normal) and less effective in reducing lateral bending (71% of normal) and axial rotation (71% of normal). Overall, ALIF with an ISA provided stability that was statistically equivalent to ALIF with bilateral pedicle screws and rods. An ISA-augmented ALIF allowed less ROM than plate-augmented ALIF during flexion, extension, and lateral bending. Use of the ISA resulted in flexion at the index level, with a resultant increase in foraminal height. Compensatory extension at the adjacent levels prevented any significant change in overall sagittal balance.

Conclusions
When used with ALIF at L4–5, the ISA provides immediate rigid immobilization of the lumbar spine, allowing equivalent ROM to that of a pedicle screw/rod system, and smaller ROM than an anterior plate. When used with ALIF, the ISA may offer an alternative to anterior plate fixation or bilateral pedicle screw/rod constructs.
The anatomy, spatial relationships, and role of uncovertebral articulations as the source of posterolateral cervical cartilage sequestrations
Authors: Browne Kenneth M. 
Published: February 2011

Object
The aim of this study was to investigate the spatial relationships of the uncovertebral articulations (UAs) with the dural origins of the C-5, C-6, and C-7 nerve roots.

Methods
The C3–7 segment of the cervical spine was removed from 18 embalmed cadavers. Spatial relationships between the C-5, C-6, and C-7 nerve roots and the UAs were examined using combinations of standard surgical approaches together with cross-sections at the level of the dural origins of the nerve roots and exposures of the floor of the spinal canal.

Results
The cartilaginous interspace that underlies the dural origin of a nerve root is the interspace of a UA. It is interposed between the central core cartilage of the disc and the dural origin of a nerve root. Cervical nerve roots do not come in contact with the interspace of an intervertebral disc at any site from their dural origin to their exit from the spinal canal. A cartilage fragment that originates from the central core cartilage of the disc may compress the intradural segment of the nerve root by migrating to that site within the epidural space, but it is blocked from reaching the dural origin of a nerve root by the interspace of a UA that is filled with fibrocartilage.

Conclusions
Anatomical considerations indicate that the source of posterolateral cervical cartilage sequestrations is the cartilaginous interspace of a UA rather than that of an intervertebral disc.
Functional outcome after resection of spinal cord hemangioblastomas associated with von Hippel-Lindau disease
Authors: Mehta Gautam U. , Asthagiri Ashok R. , Bakhtian Kamran D. , Auh Sungyoung , Oldfield Edward H. , Lonser Russell R. 
Published: February 2011

Object
Spinal cord hemangioblastomas are a common protean manifestation of von Hippel-Lindau (VHL) disease and can be associated with significant morbidity. To better define expected outcome and optimal management of these tumors in the context of this neoplasia syndrome, the authors analyzed the findings from patients with VHL disease who underwent resection of spinal cord hemangioblastomas.

Methods
Consecutive patients with VHL disease who underwent surgery for spinal cord hemangioblastomas with > 6 months follow-up were included in the study. Serial clinical examinations, functional scores, imaging findings, and operative records were analyzed.

Results
One hundred eight patients (57 male, 51 female) underwent 156 operations for resection of 218 spinal cord hemangioblastomas. One hundred forty-six operations (94%) were performed for symptom-producing tumors. The most common presenting symptoms included hypesthesia (64% of resections), hyperreflexia (57%), dysesthesia (43%), and weakness (36%). Mean follow-up was 7.0 ± 5.0 years (range 0.5–20.9 years). Complete resection was achieved for 217 tumors (99.5%). At 6-months follow-up, patients were stable or improved after 149 operations (96%) and worse after 7 operations (4%). Ventral tumors (OR 15.66, 95% CI 2.54–96.45; p = 0.003) or completely intramedullary tumors (OR 10.74, 95% CI 2.07–55.66; p = 0.005) were associated with an increased risk of postoperative worsening. The proportion of patients remaining functionally stable at 2, 5, 10, and 15 years' follow-up was 93, 86, 78, and 78%. Long-term functional decline was caused by extensive VHL-associated CNS disease (6 patients), VHL-associated visceral disease (1 patient), or non-VHL disease (2 patients).

Conclusions
Resection of symptomatic spinal cord hemangioblastomas is a safe and effective means of preserving neurological function in patients with VHL disease. Tumor location (ventral or completely intramedullary) can be used to assess functional risk associated with surgery. Long-term decline in neurological function is usually caused by VHL-associated disease progression.
Cervical spondylotic myelopathy associated with kyphosis or sagittal sigmoid alignment: outcome after anterior or posterior decompression
Authors: Uchida Kenzo , Nakajima Hideaki , Sato Ryuichiro , Yayama Takafumi , Mwaka Erisa S. , Kobayashi Shigeru , Baba Hisatoshi 
Published: February 2011

Object
The effects of sagittal kyphotic deformities or mechanical stress on the development of cervical spondylotic myelopathy, or the reduction and fusion of kyphotic sagittal alignment have not been consistently documented. The aim in this study was to determine the effects of kyphotic sagittal alignment of the cervical spine in terms of neurological morbidity and outcome after 2 types of surgical intervention.

Methods
The authors retrospectively reviewed the records of 476 patients who underwent cervical spine surgeries for spondylotic myelopathy between 1993 and 2006 at their university medical center. Among these were identified 43 patients—30 men and 13 women, with a mean age of 58.8 years—who had cervical kyphosis exceeding 10° on preoperative sagittal lateral radiographs obtained in the neutral position, and their cases were analyzed in this study. Anterior decompression with interbody fusion was conducted in 28 patients, and en bloc open-door C3–7 laminoplasty in 15 patients. Both pre- and postoperative neurological, radiographic, and MR imaging findings were assessed in both surgical groups.

Results
The mean preoperative kyphotic angle in all 43 patients was 15.9 ± 5.9° in the neutral position. Segmental instability was noted in 26 patients (61%) and reversed dynamic spinal canal stenosis at the level above the local kyphosis in 22 (51%). Preoperative T2-weighted MR images showed high-intensity signal within the cord at and around the level of maximal compression or segmental instability in 28 patients (65%). The mean kyphotic angle in both the neutral and flexion positions was significantly smaller at 4–6 weeks after surgery in the anterior spondylectomy group than in the laminoplasty group (p < 0.001). Furthermore, the angle in the neutral position was significantly smaller on follow-up in the anterior spondylectomy group than in the laminoplasty group (p = 0.034). The transverse area of the spinal cord was significantly larger in the anterior spondylectomy group than in the laminoplasty group on follow-up (p = 0.037). Preoperative neurological scores (assessed using the Japanese Orthopaedic Association scale) and improvement on follow-up ≥ 2 years after treatment (average 3.3 years) were not significantly different between the 2 groups; however, there was a significant difference in Japanese Orthopaedic Association score at 4–6 weeks postoperatively (p = 0.047).

Conclusions
Kyphotic deformity and mechanical stress in the cervical spine may play an important role in neurological dysfunction. In a select group of patients with kyphotic deformity ≥ 10°, adequate correction of local sagittal alignment may help to maximize the chance of neurological improvement.
Functional outcomes assessment for cervical degenerative disease
Authors: Holly Langston T. , Matz Paul G. , Anderson Paul A. , Groff Michael W. , Heary Robert F. , Kaiser Michael G. , Mummaneni Praveen V. , Ryken Timothy C. , Choudhri Tanvir F. , Vresilovic Edward J. , Resnick Daniel K. 
Published: February 2011

Object
The objective of this systematic review was to use evidence-based medicine to identify valid, reliable, and responsive measures of functional outcome after treatment for cervical degenerative disease.

Methods
The National Library of Medicine and Cochrane Database were queried using MeSH headings and key words relevant to functional outcomes. Abstracts were reviewed after which studies meeting inclusion criteria were selected. The guidelines group assembled an evidentiary table summarizing the quality of evidence (Classes I–III). Disagreements regarding the level of evidence were resolved through an expert consensus conference. The group formulated recommendations that contained the degree of strength based on the Scottish Intercollegiate Guidelines network. Validation was done through peer review by the Joint Guidelines Committee of the American Association of Neurological Surgeons/Congress of Neurological Surgeons.

Results
Myelopathy Disability Index, Japanese Orthopaedic Association scale, 36-Item Short Form Health Survey, and gait analysis were found to be valid and reliable measures (Class II) for assessing cervical spondylotic myelopathy. The Patient-Specific Functional Scale, the North American Spine Society scale, and the Neck Disability Index were found to be reliable, valid, and responsive (Class II) for assessing radiculopathy for nonoperative therapy. The Cervical Spine Outcomes Questionnaire was a reliable and valid method (Class II) to assess operative therapy for cervical radiculopathy.

Conclusions
Several functional outcome measures are available to assess cervical spondylotic myelopathy and cervical radiculopathy.
Laminectomy and fusion for the treatment of cervical degenerative myelopathy
Authors: Anderson Paul A. , Matz Paul G. , Groff Michael W. , Heary Robert F. , Holly Langston T. , Kaiser Michael G. , Mummaneni Praveen V. , Ryken Timothy C. , Choudhri Tanvir F. , Vresilovic Edward J. , Resnick Daniel K. 
Published: February 2011

Object
The objective of this systematic review was to use evidence-based medicine to examine the efficacy of cervical laminectomy and fusion for the treatment of cervical spondylotic myelopathy (CSM).

Methods
The National Library of Medicine and Cochrane Database were queried using MeSH headings and keywords relevant to cervical laminectomy, fusion, and CSM. Abstracts were reviewed, after which studies that met the inclusion criteria were selected. The guidelines group assembled an evidentiary table summarizing the quality of evidence (Class I–III). Disagreements regarding the level of evidence were resolved through an expert consensus conference. The group formulated recommendations which contained the degree of strength based on the Scottish Intercollegiate Guidelines network. Validation was done through peer-review by the Joint Guidelines Committee of the American Association of Neurological Surgeons/Congress of Neurological Surgeons.

Results
Cervical laminectomy with fusion (arthrodesis) improves functional outcome in patients with CSM and ossification of the posterior longitudinal ligament (OPLL). Functional improvement is similar to laminectomy or laminoplasty for patients with CSM and OPLL. In contrast to laminectomy, cervical laminectomy with fusion it is not associated with late deformity (Class III).

Conclusions
Laminectomy with fusion (arthrodesis) is an effective strategy to improve functional outcome in CSM and OPLL.
Electrophysiological monitoring during surgery for cervical degenerative myelopathy and radiculopathy
Authors: Resnick Daniel K. , Anderson Paul A. , Kaiser Michael G. , Groff Michael W. , Heary Robert F. , Holly Langston T. , Mummaneni Praveen V. , Ryken Timothy C. , Choudhri Tanvir F. , Vresilovic Edward J. , Matz Paul G. 
Published: February 2011

Object
The objective of this systematic review was to use evidence-based medicine to examine the diagnostic and therapeutic utility of intraoperative electrophysiological (EP) monitoring in the surgical treatment of cervical degenerative disease.

Methods
The National Library of Medicine and Cochrane Database were queried using MeSH headings and key words relevant to cervical spine surgery and EP monitoring. The guidelines group assembled an evidentiary table summarizing the quality of evidence (Classes I–III). The group formulated recommendations that contained the degree of strength based on the Scottish Intercollegiate Guidelines network. Validation was done through peer review by the Joint Guidelines Committee of the American Association of Neurological Surgeons/Congress of Neurological Surgeons.

Results
The reliance on changes in EP monitoring as an indication to alter a surgical plan or administer steroids has not been observed to reduce the incidence of neurological injury during routine surgery for cervical spondylotic myelopathy or cervical radiculopathy (Class III). However, there is an absence of study data examining the benefit of altering a surgical plan due to EP changes.

Conclusions
Although the use of EP monitoring may serve as a sensitive means to diagnose potential neurological injury during anterior spinal surgery for cervical spondylotic myelopathy, the practitioner must understand that intraoperative EP worsening is not specific—it may not represent clinical worsening and its recognition does not necessarily prevent neurological injury, nor does it result in improved outcome (Class II). Intraoperative improvement in EP parameters/indices does not appear to forecast outcome with reliability (conflicting Class I data).