bluuebunny/crossref_metadata_2025 huggingface dataset:
When “Abegg” is read and (“A, B, E, G, G”) is not: a cortical stimulation study of musical score reading
Authors: Roux Franck-Emmanuel , Lubrano Vincent , Lotterie Jean-Albert , Giussani Carlo , Pierroux Clémence , Démonet Jean-François
Published: January 2008

Object

To spare the cortical areas involved both in musical score reading and in language, the authors used a score reading task during direct cortical stimulation mapping in musicians undergoing operations for brain lesions. The organization of the cortical areas involved in language and score reading, respectively, was analyzed in relation with these surgical data.

Methods

Seven patients with brain lesions were tested using three language tasks and a score-reading task. Preoperatively, none of them had exhibited significant language or musical ability deficits, and all had a special interest in music. All were involved in professional or amateur musical activities.

Interference in score reading was found in small cortical areas, mainly in the dominant parietal lobe and sometimes in the frontal gyri. During direct stimulation, interference was either language-specific (15 sites), common to language and score-reading tasks (18 sites), or specific to the score-reading task (four sites). Different patterns of score-reading interferences (score-reading arrest, semantic paraphasia) were observed, probably corresponding to different stages of score reading. Postoperatively, some patients showed transitory score-reading difficulties related to the surgical procedure.

Conclusions

The cortical areas involved in score reading can occasionally be distinct from other language areas. This could explain differential word- and score-reading impairments sometimes observed in musicians with brain lesions. Brain mapping for neurosurgical procedures in musicians should ideally be performed using a score-reading task in addition to standard language tasks, especially for mapping in the dominant parietal lobe.
Inflammatory myofibroblastic tumor of the ulnar nerve
Authors: Schittenhelm Jens , Kaminsky Jan , Meyermann Richard , Mittelbronn Michel
Published: January 2008

✓Inflammatory myofibroblastic tumors with involvement of cranial and peripheral nerves are exceedingly rare. The authors present the case of a 67-year-old man with an inflammatory myofibroblastic tumor of the left ulnar nerve, which was identified intraoperatively and mimicked a malignant neoplastic lesion. Histopathological examination revealed loosely structured fibrous tissue and collagen deposits intermingled with patchy infiltrates of lymphocytes, plasma cells, and histiocytes penetrating the endo- and epineurium of the affected nerve fascicles. There was strong expression of vimentin and actin in spindle cells throughout the lesion. The histiocytes were CD68- and major histocompatibility complex class II–positive, but lacked CD1a expression. A review of the literature revealed nine histopathologically confirmed cases of inflammatory myofibroblastic tumors involving peripheral or cranial nerves in which slight differences in histopathological features and surgical management were found, which are discussed here.
Otogenic tension pneumocephalus complicated by eustachian tube insufflation in a patient with a ventriculoperitoneal shunt
Authors: Nagai Hidemasa , Moritake Kouzo
Published: January 2008

✓Spontaneous tension pneumocephalus (TPC) related to shunt surgery has sometimes been reported with reference to the Valsalva maneuver and osseous defects of the tegmen tympani. Here, the authors report on a case of TPC complicated by eustachian tube (ET) insufflation and a ventriculoperitoneal (VP) shunt. This 78-year-old man had undergone VP shunt insertion 3 weeks before readmission to the hospital with a diagnosis of TPC, a left temporal porencephalic cyst, and air accumulation and late leakage of cerebrospinal fluid (CSF) into the left tympanic cavity. The TPC was controlled successfully by ligation of the shunt tube. The authors discuss the pathophysiology of this complicated TPC case, which illustrates the risk of ET insufflation in patients undergoing CSF shunt surgery.
Range of motion change after cervical arthroplasty with ProDisc-C and Prestige artificial discs compared with anterior cervical discectomy and fusion
Authors: Chang Ung-Kyu , Kim Daniel H. , Lee Max C. , Willenberg Rafer , Kim Se-Hoon , Lim Jesse
Published: January 2008

Object

Range of motion (ROM) changes were evaluated at the surgically treated and adjacent segments in cadaveric specimens treated with two different cervical artificial discs compared with those measured in intact spine and fusion models.

Methods

Eighteen cadaveric human cervical spines were tested in the intact state for the different modes of motion (extension, flexion, lateral bending, and axial rotation) up to 2 Nm. Three groups of specimens (fitted with either the ProDisc-C or Prestige II cervical artificial disc or submitted to anterior cervical discectomy and fusion [ACDF]) were tested after implantation at C6–7 level. The ROM values were measured at treated and adjacent segments, and these values were then compared with those measured in the intact spine.

Results

At the surgically treated segment, the ROM increased after arthroplasty compared with the intact spine in extension (54% in the ProDisc-C group, 47% in the Prestige group) and in flexion (27% in the ProDisc-C group, 10% in the Prestige group). In bending and rotation, the postarthroplasty ROMs were greater than those of the intact spine (10% in the ProDisc-C group and 55% in the Prestige group in bending, 17% in the ProDisc-C group and 50% in the Prestige group in rotation). At the adjacent levels the ROMs decreased in all specimens treated with either artificial disc in all modes of motion (< 10%) except for extension at the inferior the level (29% decrease for ProDisc-C implant, 12% decrease for Prestige disc). The ROM for all motion modes in the ACDF-treated spine decreased at the treated level (range 18–44%) but increased at the adjacent levels (range 3–20%).

Conclusions

Both ProDisc-C and Prestige artificial discs were associated with increased ROM at the surgically treated segment compared with the intact spine with or without significance for all modes of testing. In addition, adjacent-level ROM decreased in all modes of motion except extension in specimens fitted with both artificial discs.
Endoscopic biopsy sampling of tophaceous gout of the odontoid process
Authors: Fraser Justin F. , Anand Vijay K. , Schwartz Theodore H.
Published: January 2008

✓The authors present the case of a 71-year-old man who presented with neck pain, a history of gout, and a mass in the dens. Results of transoral endoscopic biopsy sampling demonstrated tophaceous gout. The patient was treated medically and the pain resolved. Tophaceous gout isolated in the dens is extremely rare and should be considered in the differential diagnosis of masses in this region. With the aid of transoral or transnasal endoscopic biopsy sampling, the diagnosis can be reached in a minimally invasive manner.
Total L-5 spondylectomy and reconstruction of the lumbosacral junction
Authors: Gallia Gary L. , Sciubba Daniel M. , Bydon Ali , Suk Ian , Wolinsky Jean-Paul , Gokaslan Ziya L. , Witham Timothy F.
Published: January 2008

✓The authors describe a technique for total L-5 spondylectomy and reconstruction of the lumbosacral junction. The technique, which involves separately staged posterior and anterior procedures, is reported in two patients harboring neoplasms that involved the L-5 level. The first stage consisted of a posterior approach with removal of all posterior bone elements of L-5 and radical L4–5 and L5–S1 discectomies. Lumbosacral and lumbopelvic instrumentation included pedicle screws as well as iliac screws or a transiliac rod. The second stage consisted of an anterior approach with mobilization of vascular structures, completion of L4–5 and L5–S1 discectomies, and removal of the L-5 vertebral body. Anterior lumbosacral reconstruction included placement of a distractable cage and tension band between L-4 and S-1. Allograft bone was used for fusion in both stages. No significant complications were encountered. At more than 1 year of follow-up, both patients were independently ambulatory, without evidence of recurrent or metastatic disease, and adequate lumbosacral alignment was maintained. The authors conclude that this technique can be safely performed in appropriately selected patients with neoplasms involving L-5.
New prognostic factors for adjacent-segment degeneration after one-stage 360° fixation for spondylolytic spondylolisthesis: special reference to the usefulness of pelvic incidence angle
Authors: Park Jeong Yoon , Cho Yong Eun , Kuh Sung Uk , Cho Jun Hyung , Chin Dong Kyu , Jin Byung Ho , Kim Keun Su
Published: January 2008

Object.

The purpose of this study was to evaluate the correlation between adjacent-segment degeneration (ASD) and pelvic parameters in the patients with spondylolytic spondylolisthesis. Sagittal balance is the most important risk and prognostic factor in the development of ASD. The pelvic incidence angle (PIA) is an important anatomical parameter in determining the sagittal curvature of the spine and in the individual variability of the sacral slope and the lordotic curve. Thus, the authors evaluated the relationship between the pelvic parameters and the ASD.

Methods.

Among 132 patients with spondylolytic spondylolisthesis who underwent surgery at their institution, the authors selected patients in whom a one-stage, single-level, 360° fixation procedure was performed for Grade I spondylolisthesis and who underwent follow-up for more than 1 year. Parameters in 34 patients satisfied these conditions. Of the 34 patients, seven had ASD (Group 1) and 27 patients did not have ASD (Group 2). The investigators measured degree of spondylolisthesis, lordotic angle, sacral slope angle (SSA), pelvic tilt angle (PTA), PIA, and additional parameters pre-and postoperatively. The radiographic data were reviewed retrospectively.

Results.

The population consisted of nine men and 25 women whose mean age was 48.9 ± 9 years (± standard deviation) (range 28–65 years). Seven patients developed ASD after undergoing fusion. Of all the parameters, pre-and postoperative degree of spondylolisthesis, segmental lordosis, lordotic angle, SSA, preoperative PTA, and pre-operative PIA did not differ significantly between the two groups; only postoperative PTA and PIA were significantly different.

Conclusions.

The development of ASD is closely related to postoperative PIA and PTA, not preoperative PIA and PTA. The measurement of postoperative PIA can be used as a new indirect method to predict the ASD.
Thoracic ossification of the human ligamentum flavum: histopathological and immunohistochemical findings around the ossified lesion
Authors: Yayama Takafumi , Uchida Kenzo , Kobayashi Shigeru , Kokubo Yasuo , Sato Ryuichiro , Nakajima Hideaki , Takamura Takaharu , Bangirana Alexander , Itoh Hiroshi , Baba Hisatoshi
Published: January 2008

Object.

The object of this study was to histopathologically and immunohistochemically characterize ossification of the ligamentum flavum (OLF) in samples of the thoracic spine harvested en bloc during surgery and to enhance the understanding of the ossifying process, particularly calcification and ossification.

Methods.

Samples of OLF plaque were obtained en bloc from 43 patients who underwent posterior decompression. The histopathological findings were correlated with radiological subtypes using computed tomography. The expression of type I and type II collagens, vascular endothelial growth factor (VEGF), transforming growth factor (TGF)β, and bone morphogenetic protein (BMP)–2 was investigated.

Results.

Surgical decompression using the posterior floating and en bloc resection technique resulted in neurological improvement in 40 of 43 patients. Progression of the OLF lesion longitudinally and medially was associated with significant degeneration of elastic fibers, fiber bundle derangement, decrements in fiber diameter, and fragmentation. Calcification and ossification paralleled the degeneration of the elastic fibers, extended more medially, and fused in the central area. Expression of BMP-2, TGFβ, and VEGF was significant in chondrocytes in the calcified cartilage and fibrocartilage layers, especially around the calcified front.

Conclusions.

Histopathologically, the progress of calcification and ossification was closely associated with the degeneration of elastic fibers and with significant expression of BMP-2, TGFβ, and VEGF in the ossification front.
Atlantoaxial subluxation–induced myelopathy in cleidocranial dysplasia
Authors: Kobayashi Shigeru , Uchida Kenzo , Baba Hisatoshi , Takeno Kenichi , Yayama Takasi , Nakajima Hideaki , Nomura Eiki , Yoshizawa Hidezo
Published: January 2008

✓The authors describe the clinical course and treatment of a patient with cleidocranial dysplasia in whom spastic myelopathy developed due to atlantoaxial subluxation. This 27-year-old woman with cleidocranial dysplasia and a history of atlantoaxial subluxation presented with spastic myelopathy. Surgery was performed twice for cervical myelopathy and atlantoaxial subluxation, including laminectomy at the atlas and cervicooccipital fusion in which the Luque rod system was used, as well as C1–2 fusion via the transpharyngeal route. Solid bone fusion was achieved by 7 months postsurgery. Postoperative magnetic resonance imaging studies demonstrated that spinal cord compression was relieved, but atrophy persisted. At 2 years postsurgery there was no neurological disease progression, but spasticity persisted. The patient could walk with a cane. Cleidocranial dysplasia is an extremely rare cause of myelopathy in patients with atlantoaxial subluxation; the authors know of only two reports of this condition. When managing cleidocranial dysplasia, the practitioner should always be aware that atlantoaxial subluxation may be the cause of cervical myelopathy.
Multiple filum terminale hemangioblastomas symptomatic during pregnancy
Authors: Ortega-Martínez Marta , Cabezudo Jose M. , Fernández-Portales Ignacio , Pineda-Palomo Manuel , Rodríguez-Sánchez Jose Antonio , Bernal-García Luis Miguel
Published: January 2008

✓Hemangioblastomas are low-grade, highly vascular tumors commonly associated with von Hippel–Lindau (VHL) syndrome and most often appearing in the cerebellum. They very rarely occur in the spinal nerve roots, and an origin in the filum terminale is exceptional with no instances of multiple hemangioblastomas of the filum terminale reported in the literature. Because of their vascular nature, these lesions can enlarge and become symptomatic in the context of the changes that take place during pregnancy, as has been noted with cerebellar hemangioblastomas. In any case, the evolution of spinal hemangioblastomas during pregnancy is not well known given its rarity. The conjunction of both processes—that is, multiple hemangioblastomas arising in the filum terminale and pregnancy—is unique. The authors describe the case of a 41-year-old woman with multiple hemangioblastomas of the filum terminale and no other evidence of VHL syndrome, in whom pregnancy precipitated symptoms. The interruption of gestation led to a remission of the symptoms. The literature concerning filum terminale hemangioblastomas and pregnancy is also reviewed.
Lateral intramuscular planar approach to the lumbar spine and sacrum
Authors: Weaver Edgar Newman
Published: January 2008

✓The goal of this study was to establish a much less invasive method for access to the lateral lumbar spine for posterolateral fusion and pedicle screw (PS) placement.

The technique was developed through knowledge of the anatomy literature and the author's clinical experience in more than 90 completed cases.

The lateral intramuscular planar approach provides a much less invasive access to the lateral aspect of the lumbar spine and sacrum. An invariant intramuscular plane, poorly described in the anatomical literature, is ideal for postero-lateral fusion and/or PS placement from L-3 caudally. The approach requires essentially no resection of the multifidus muscle, or of the pars thoracis of the erector spinae.
Trends in pathological vertebral fractures in the United States: 1993 to 2004
Authors: Lad Shivanand P. , Patil Chirag G. , Lad Eleonora Maries , Boakye Maxwell
Published: January 2008

Object

Pathological vertebral fractures (PVFs) are an increasingly important cause of disability and have many clinical and economic implications. The authors examined trends in epidemiology and surgical management of pathological vertebral fractures in the US between 1993 and 2004.

Methods

The Nationwide Inpatient Sample database was used to analyze data collected from 1993 through 2004 to determine general trends in PVFs. Patients with PVFs were identified using the appropriate International Classification of Diseases, 9th Revision (ICD-9) diagnostic code (ICD-9 733.13). Trends in vertebral augmentation procedures and spinal fusions as well as comparison with incidences of other major pathological fractures, such as hip and upper limb, were also examined.

Results

In 2004, there were more than 55,000 inpatient admissions for PVFs. The majority of patients admitted were women (78%) in the 65 to 84 year–age group (60%). Medicare accounted for greater than 80% of insurance, and nearly 50% of all patients were admitted from the emergency department. The mean duration of hospitalization has continued to decrease, from 8.1 days in 1993 to 5.4 days in 2004. The mortality rate has remained relatively constant at approximately 1.5%. The discharge disposition has continued to change with an increasing number of patients being discharged to other institutions such as nursing homes and rehabilitation facilities. There was a staggering increase in the number of vertebral augmentation procedures performed between 1993 and 2004. The “national bill” for inpatient hospitalizations for PVFs totaled $1.3 billion in 2004.

Conclusions

With the continued aging of the population, PVFs represent an important cause of disability and a significant source of healthcare resource utilization.
In vitro biomechanical comparison of an anterior and anterolateral lumbar plate with posterior fixation following single-level anterior lumbar interbody fusion
Authors: Johnson Wesley M. , Nichols Tann A. , Jethwani Deepika , Guiot Bernard H.
Published: January 2008

Object

Anterior lumbar interbody fusion (ALIF) is often supplemented with instrumentation to increase stability in the spine. If anterior plate fixation provided the same stability as posterior pedicle screw fixation (PSF), then a second approach and its associated morbidity could be avoided.

Methods

Seven human cadaveric L4–5 spinal segments were tested under three conditions: ALIF with an anterior plate, ALIF with an anterolateral plate, and ALIF supplemented by PSF. Range of motion (ROM) was calculated for flexion/extension, lateral bending, and axial torsion and compared among the three configurations.

Results

There were no significant differences in ROM during flexion/extension, lateral bending, or axial torsion among any of the three instrumentation configurations.

Conclusions

The addition of an anterior plate or posterior PS/rod instrumentation following ALIF provides substantially equivalent biomechanical stability. Additionally, the position of the plate system, either anterior or anterolateral, does not significantly affect the stability gained.
Cortex of the pedicle of the vertebral arch. Part I: deformation characteristics during screw insertion
Authors: Serkan İnceoğlu , Kılınçer Cumhur , Tami Andrea , McLain Robert F.
Published: January 2008

Object

Elastic deformation has been proposed as a mechanism by which vertebral pedicles can maintain pullout strength when conical screws are backed out from full insertion. The response to the insertion technique may influence both the extent of deformation and the risk of acute fracture during screw placement. The aim of this study was to determine the deformation characteristics of the lumbar pedicle cortex during screw placement.

Methods

Lumbar pedicles with linear strain gauges attached at the lateral and medial cortices were instrumented using 7.5-mm pedicle screws with or without preconditioning by insertion and removal of 6.5-mm screws. The strains and elastic recoveries of the medial and lateral cortices were determined.

Results

Mean medial wall strains tended to be lower than mean lateral wall strains when the 6.5-mm and 7.5-mm screw data were pooled (p = 0.07). After the screws had been removed, 71 to 79% of the deformation at the lateral cortex and 70 to 96% of the deformation at the medial cortex recovered. When inserted first, the 7.5-mm screw caused more plastic deformation at the cortex than it did when inserted after the 6.5-mm screw. Occasional idiosyncratic strain patterns were observed. No gross fracture was observed during screw placement.

Conclusions

Screw insertion generated plastic deformation at the pedicle cortex even though the screw did not directly contact the cortex. The lateral and medial cortices responded differently to screw insertion. The technique of screw insertion affected the deformation behavior of the lumbar pedicles. With myriad options for screw selection and placement available, further study is needed before optimal placement parameters can be verified.
Lumbar radiculopathy caused by extradural rheumatoid nodules
Authors: Hirohashi Nori , Sakai Toshinori , Sairyo Koichi , Oba Koichi , Higashino Kosaku , Katoh Shinsuke , Yasui Natsuo
Published: January 2008

✓The authors report on a 51-year-old woman with a 9-year history of rheumatoid arthritis (RA) who presented with symptomatic rheumatoid nodules in the lumbar extradural region with compression on the L-5 nerve roots bilaterally. She had also suffered from dysesthesia in the right lower leg and intermittent claudication. Magnetic resonance imaging revealed masses compressing the dural sac, and on lumbar myelography and computed tomography myelography a filling defect at L4–5 was revealed, which was compressing the dural sac posterolaterally on both sides. The masses were surgically removed. On histological examination the typical characteristics of rheumatoid nodules were found. Soon after the operation all of the patient's symptoms disappeared.

There have been few reports on extradural rheumatoid nodules. Patients with RA usually complain of articular symptoms, and in fact the patient in the present study had been referred to the authors' institution for total hip arthroplasty. However, various symptoms other than those arising from articular lesions were found clinically. The authors believe that if patients with RA are also examined for extraarticular lesions, it is likely that these will be more frequently detected.
Progressive myelopathy due to idiopathic intraspinal tumoral calcinosis of the cervical spine
Authors: Miyakoshi Naohisa , Shimada Yoichi , Kasukawa Yuji , Ando Shigeru
Published: January 2008

✓Tumoral calcinosis is a rare disorder that most often occurs in periarticular regions of the extremities. Here, the authors report on an extremely rare case of idiopathic intraspinal tumoral calcinosis of the cervical spine. This 54-year-old man presented with a 2-week history of progressive cervical myelopathy. Results of magnetic resonance imaging and computed tomography myelography of the cervical spine revealed an intraspinal calcified mass lesion posterior to the spinal cord at the C3–4 level, resulting in marked spinal cord compression. Spinal cord decompression and en bloc resection of the mass lesion were performed via a C-2 laminoplasty and C3–4 laminectomy. The mass was localized in the dura mater. Histologically, the lesion consisted of numerous nodules with amorphous calcified materials and a florid proliferation of multinucleated giant cells; that is, its histological characteristics were identical to those of tumoral calcinosis. The symptoms disappeared completely after surgery. In all previously reported cases of cervical tumoral calcinosis, the lesion was located in the paraspinal soft tissue, with bone and facet joint involvement. The present case is the first reported instance of cervical tumoral calcinosis localized only in the spinal canal.
Spinous process plate fixation as a salvage operation for failed anterior cervical fusion
Authors: Neo Masashi , Fujibayashi Shunsuke , Yoshida Makoto , Nakamura Takashi
Published: January 2008

✓The purpose of this retrospective review was to demonstrate the effectiveness of simple spinous process plate fixation as a salvage operation for failed anterior cervical fusion (ACF). In this technique, the spinous processes are securely sandwiched between a pair of plates with thorns, which are squeezed together by tightening screws that extend through the plates. The authors salvaged six failed ACFs (nonunion of bone graft, plate migration, or bone graft dislodgment) by conducting this fixation without bone grafting, or with an anterior or posterior local bone graft only. Anterior bone union was attained within 6 months in all cases. This technique is easy to perform and probably provides more mechanical strength than does conventional spinous process wiring, resulting in prompt fusion without the need for a new massive bone graft. This technique is a practical option in salvage operations for failed ACF.
Intrarater and interrater reliability and validity in the assessment of the mechanism of injury and integrity of the posterior ligamentous complex: a novel injury severity scoring system for thoracolumbar injuries
Authors: Harrop James S. , Vaccaro Alexander R. , Hurlbert R. John , Wilsey Jared T. , Baron Eli M. , Shaffrey Christopher I. , Fisher Charles G. , Dvorak Marcel F. , Öner F. C. , Wood Kirkham B. , Anand Neel , Anderson D. Greg , Lim Moe R. , Lee Joon Y. , Bono Christopher M. , Arnold Paul M. , Rampersaud Y. Raja , Fehlings Michael G. , _ _
Published: January 2008

Object

A new classification and treatment algorithm for thoracolumbar injuries was recently introduced by Vaccaro and colleagues in 2005. A thoracolumbar injury severity scale (TLISS) was proposed for grading and guiding treatment for these injuries. The scale is based on the following: 1) the mechanism of injury; 2) the integrity of the posterior ligamentous complex (PLC); and 3) the patient’s neurological status. The reliability and validity of assessing injury mechanism and the integrity of the PLC was assessed.

Methods

Forty-eight spine surgeons, consisting of neurosurgeons and orthopedic surgeons, reviewed 56 clinical thoracolumbar injury case histories. Each was classified and scored to determine treatment recommendations according to a novel classification system. After 3 months the case histories were reordered and the physicians repeated the exercise. Validity of this classification was good among reviewers; the vast majority (> 90%) agreed with the system’s treatment recommendations. Surgeons were unclear as to a cogent description of PLC disruption and fracture mechanism.

Conclusions

The TLISS demonstrated acceptable reliability in terms of intra- and interobserver agreement on the algorithm’s treatment recommendations. Replacing injury mechanism with a description of injury morphology and better definition of PLC injury will improve inter- and intraobserver reliability of this injury classification system.
Occipitocervical fusion after resection of craniovertebral junction tumors
Authors: Shin Hyunchul , Barrenechea Ignacio J. , Lesser Jonathan , Sen Chandranath , Perin Noel I.
Published: January 2008

Object

Surgical access to tumors at the craniovertebral junction (CVJ) requires extensive bone removal. Guidelines for the use of occipitocervical fusion (OCF) after resection of CVJ tumors have been based on anecdotal evidence. The authors performed a retrospective study of factors associated with the use of OCF in 46 patients with CVJ tumors. The findings were used to develop recommendations for use of OCF in such patients.

Methods

The authors retrospectively reviewed the cases of 51 patients with CVJ tumors treated by their group between March 1991 and February 2004. Forty-six patients were available for follow up. Charts were reviewed to obtain data on demographic characteristics, presenting symptoms, and perioperative complications. Preoperative computerized tomography scans and magnetic resonance imaging studies were obtained in all patients. Occipitocervical fusion was performed in patients who had undergone a unilateral condyle resection in which 70% or more of the condyle was removed, a bilateral condyle resection with 50% removal, or C1–2 vertebral body destruction. Of the 46 patients, 16 had foramen magnum meningiomas, 17 had chordomas, one had a chondrosarcoma, two had Schwann cell tumors, two had glomus tumors, and eight had other types of tumors. Twenty-three (50%) of the 46 patients underwent OCF, including 15 of the 17 patients with chordomas (88%). None of the patients with meningiomas required fusion. Seventeen (71%) of the 24 patients presenting with neck pain preoperatively underwent OCF.

Conclusions

Patients presenting with neck pain had a 71% chance of undergoing OCF. Patients with chordomas and metastatic tumors were most likely to require OCF. One patient with a 50% unilateral condylar resection returned with OC instability for which OCF was required. Based on their clinical experience and published biomechanical studies, the authors recommend that OCF be performed when 50% or more of one condyle is resected.
The biomechanical evaluation of calcium phosphate cements for use in vertebroplasty
Authors: Hong Suk-Joo , Park Youn-Kwan , Kim Jung Hyuk , Lee Soon Hyuck , Ryu Kyung Nam , Park Cheol Min , Kim Yeon Soo
Published: January 2008

Object

The authors evaluate the biomechanical properties of vertebral bodies (VBs) stabilized with calcium phosphate (CaP) cements for use in vertebroplasty in comparison with polymethylmethacrylate (PMMA).

Methods

In the first phase of the study, 73 VBs (T3–L2; thoracic region [T3–8] and thoracolumbar region [T9–L2]) were collected from seven fresh human cadavers. Compression tests were performed before and after vertebroplasty using PMMA (compression strength 80 MPa) and three kinds of CaP cements—CaP1 (5 MPa), CaP2 (20 MPa), and CaP3 (50 MPa). The authors compared the maximal compression loads (MCLs) and stiffness before and after vertebroplasty in each of the four cement groups. In the second phase of the study, 18 paired spinal units (PSUs) were collected from three fresh human cadavers, and the authors injected two types of cement selected from the first phase of the study into the lower level of six PSUs. They compared the MCLs of the untreated and two treated groups (there were six PSUs in each type of group) to analyze the tendency of inducing compression fractures in the upper level of the PSUs.

The MCLs of the PMMA-injected vertebrae were significantly increased after vertebroplasty. The MCL levels of the CaP3-injected vertebrae and the CaP2-injected thoracolumbar vertebrae were decreased from those of untreated vertebrae without being significant. The MCLs of CaP1-injected vertebrae and CaP2-injected thoracic vertebrae were significantly decreased after vertebroplasty. The stiffness of all cement groups was decreased after vertebroplasty compared with initial stiffness, significantly so in all three thoracic CaP groups. In the second compression test with PSUs, the MCLs of the CaP2- and CaP3-injected PSUs were not significantly different from those of the untreated control PSUs.

Conclusions

The CaP3-injected vertebrae restored the MCLs of human vertebrae closer to their initial levels than the PMMA-injected vertebrae did. The CaP2- and CaP3-injected PSUs showed no tendency to induce compression fractures in adjacent VBs.
Surgical treatment of 40 patients with thoracic ossification of the ligamentum flavum
Authors: Li Fangcai , Chen Qixin , Xu Kan
Published: January 2008

Object

The authors evaluated different surgical methods used to treat thoracic ossification of the ligamentum flavum (OLF).

Methods

Data obtained in 40 patients who underwent posterior decompression for thoracic myelopathy caused by thoracic OLF were studied retrospectively. There were 32 men and eight women. All patients underwent posterior decompression in which laminoplasty was performed or laminectomy combined with lateral fusion. Every surgical specimen was stained with H & E, and scanning electron microscopy was performed in 20 cases. The mean follow-up period was 28 months. Postoperative outcomes were evaluated using a recovery scale based on the Japanese Orthopaedic Association classification. There were a total of 168 ossified segments in this series, 77.4% of which were located in the lower thoracic spine. Marginal osteophyte formation was found in 36 patients; in 32 of the 36 patients, these marginal osteophytes were located at the intervertebral space either higher or lower than the ossified segment. Scanning electron microscopy showed elastic fiber breakdown, proliferation of collagenous fibers, calcification, and OLF in the same microscopy region. Laminoplasty was performed in four patients. In three cases surgery resulted in unchanged or worse outcome (increased kyphotic deformity in two), and in one it resulted in good outcome. Laminectomy combined with lateral fusion was performed in 36 patients, in 30 cases of which it resulted in a good or fair outcome, and increased kyphotic deformity in only one. Of these 36 laminectomy-treated patients, an en bloc laminectomy-treated procedure was performed in 16 patients; in 11 of the 12 patients with lateral or diffuse-type lesions the surgery resulted in a good or fair outcome. En bloc laminectomy, however, seems ineffective in the treatment of patients with thickened, nodular-type thoracic OLF, as the procedure resulted in worse outcome in two of the four patients. The authors have thus developed a new modality of laminectomy that they have termed “separating laminectomy,” which they performed in 16 patients with thickened, nodular-type OLF; in 13 cases it resulted in a good or fair outcome, and in only one case did it result in a worse outcome.

Conclusions

The pathogenesis of thoracic OLF is mainly due to the localized mechanical stress on the ligament. Laminectomy combined with lateral fusion is the treatment of choice for thoracic OLF; furthermore, in terms of the configuration of the ossified lesion, en bloc laminectomy is suitable for the treatment of lateral-type and diffuse-type OLF, and the separating laminectomy is suitable for the thickened, nodular-type OLF.
Sacral epithelioid angiosarcoma associated with a bleeding diathesis and spinal epidural hematoma
Authors: Sanchez-Mejia Rene O. , Ojemann Steven G. , Simko Jeff , Chaudhary Uzair B. , Levy Jay , Lawton Michael T.
Published: January 2008

✓Epithelioid angiosarcoma of bone is a rare, high-grade lesion that is highly vascular and can be associated with a bleeding diathesis. An association has been reported in angiosarcomas in other locations with coagulopathy from tumor-related disseminated intravascular coagulopathy and fibrinolysis. The authors report the case of a rare occurrence of a primary sacral epithelioid angiosarcoma associated with a large epidural hematoma and a severe bleeding diathesis.

A 25-year-old woman presented with weakness, fatigue, neck and low-back pain, and progressive left S-1 radiculopathy. Imaging studies revealed a large ventral epidural hematoma extending from the sacral region rostrally to C-2 and a vascular tumor located in the sacrum. The patient underwent a sacral laminectomy, complicated by postoperative bleeding from the wound, and required massive transfusions. Ultimately, multimodal therapy was required to obtain hemostasis, including the use of endovascular embolization, radiation therapy, and an infusion of epsilon-aminocaproic acid with heparin. This case represents the first report of a primary epithelioid angiosarcoma in the sacrum and emphasizes that the coagulopathy seen in angiosarcoma is also a feature of this epithelioid variant.
Expansive duraplasty for the treatment of spinal extradural arachnoid cysts
Authors: Kikuta Ken-ichiro , Hojo Masato , Gomi Masanori , Hashimoto Nobuo , Nozaki Kazuhiko
Published: January 2008

✓ The authors report the case of a 25-year-old man with a thoracolumbar extradural arachnoid cyst who underwent expansive duraplasty. Symptoms, preoperative magnetic resonance imaging features, and intraoperative findings suggested the involvement of entrapment neuropathy in the manifestation of symptoms. To the authors’ knowledge, this case represents the first evidence that expansive duraplasty can achieve complete resolution of the symptoms in a patient with a spinal extradural arachnoid cyst. The results indicate that duraplasty may be an alternative option in cases in which complete resection of the lesion is difficult and widening of the dural sac is necessary at surgery.
The intracranial entrance of the atlantal segment of the vertebral artery in crania with occipitalization of the atlas
Authors: Tubbs R. Shane , Salter E. George , Oakes W. Jerry
Published: January 2008

Object

An anomalous vertebral artery (VA) position can jeopardize an otherwise successful procedure, such as a posterior cranial fossa decompression for hindbrain herniation, and may increase the propensity for VA occlusion.

Methods

The authors describe the detailed anatomy of the entrance site of the VA in adult human crania in which there is occipitalization of the atlas. They found that if the atlantal posterior arch or hemiarch was fused to the occiput one should anticipate encountering an anomalous osseous pathway as the VA enters into the cranium, as evidenced by this finding in 80% of their specimens. An anomalous entry pathway was present in all but one left-sided specimen in which the left posterior hemiarch was not fused to the occiput and one right-sided specimen in which there was an unfused and rudimentary posterior arch of the atlas.

Conclusions

The clinician should consider the possibility that the VA takes anomalous routes into the skull in cases in which there is occipitalization of the atlas.
The role of mitomycin C in reducing recurrence of epidural fibrosis after repeated operation in a laminectomy model in rats
Authors: Lee Jin-Yul , Stenzel Werner , Löhr Mario , Stützer Hartmut , Ernestus Ralf-Ingo , Klug Norfrid
Published: January 2008

Object

Extensive peridural fibrosis after lumbar spine surgery may contribute to poor outcome and recurrent symptoms leading to repeated operation. Secondary procedures are considerably hampered by the presence of scar tissue. Moreover, after excision of the peridural scar, the fibrous tissue may recur, leading to unsuccessful surgical outcome. Mitomycin C (MMC), an alkylating antibiotic substance isolated fromStreptomyces caespitosus, potentially suppresses fibroblast proliferation after surgical intervention. The authors investigated the effect of MMC on the reformation of epidural fibrosis in a laminectomy model in rats.

Methods

Twenty-four Wistar rats underwent a repeated lumbar laminectomy 3 months after the first operation. In 12 rats, MMC in a concentration of 1 mg/ml was locally applied to the laminectomy site. No treatment was performed in the control group of the other 12 rats. All rats underwent clinical evaluation. Mobility ratings and any evidence of neurological deficit were recorded. Twelve weeks after the second operation, the animals were killed for histological examination. The extent of epidural fibrosis and dural adherence was evaluated.

All MMC-treated animals showed reduced epidural scarring, compared with the control group. In nine MMC-treated rats (75%), dural adhesions were moderate. In contrast, all control sites showed dense epidural fibrosis with marked dural adherence. No side effects of the treatment were observed.

Conclusions

In this experimental study, MMC in a concentration of 1 mg/ml locally applied significantly reduced recurrence of epidural fibrosis and dural adhesions without any side effects after repeated spinal surgery in a laminectomy model in rats.
Aggressive postoperative lumbar fibromatosis after the placement of instrumentation for treatment of spondylolisthesis
Authors: Güzey Feyza Karagöz , Emel Erhan , Bas N. Serdar , Ozkan Nezih , Turgut Hurriyet , Sel Baris
Published: January 2008

✓ This 50-year-old woman presented with a paravertebral lumbar fibromatosis (desmoid tumor) after undergoing the placement of instrumentation for lumbar spondylolisthesis. The tumor developed just cranial to the previous skin incision. Fibromatoses, or desmoid tumors, are uncommon infiltrative lesions that affect musculoaponeurotic structures, most often of the trunk and limbs. They are known to occur in association with surgery-related scars or implants and only rare examples appear in the neurosurgical and spine-related literature. In cases involving well-defined tumors in which radical resection is possible, surgery is the treatment of choice; however, the recurrence rate is high. The patient in the present case was followed for 14 months postoperatively and did not undergo radiotherapy; there was no recurrence.

Although rare, this distinctive tumor should be considered in the differential diagnosis of postoperative paravertebral bulgings after neurosurgical and spinal operations.
Microendoscopic partial resection of the sacral ala to relieve extraforaminal entrapment of the L-5 spinal nerve at the lumbosacral tunnel
Authors: Matsumoto Morio , Chiba Kazuhiro , Ishii Ken , Watanabe Kota , Nakamura Masaya , Toyama Yoshiaki
Published: January 2008

✓ The authors report the cases of three patients with L-5 radiculopathy caused by extraforaminal entrapment of the L-5 spinal nerve at the lumbosacral tunnel; this structure comprises the lumbosacral ligament, the sacral ala, and the L-5 and S-1 vertebral bodies. All three patients suffered severe leg pain and neurological deficits compatible with L-5 radiculopathy. Decompressive surgery involved the microendoscopic partial resection of the sacral ala along the L-5 spinal nerve. All patients experienced immediate pain relief postoperatively. Microendoscopic partial resection of the sacral ala is an effective and minimally invasive surgical option for patients with extraforaminal entrapment of the L-5 spinal nerve.
Cervical radiofrequency neurotomy in patients with chronic whiplash: a study of multiple outcome measures
Authors: Prushansky Tamara , Pevzner Evgeny , Gordon Carlos , Dvir Zeevi
Published: January 2008

Object

Cervical radiofrequency neurotomy (CRFN) is used in the treatment of patients with chronic pain and disability due to whiplash injury. Confirmation of its efficiency has, however, been based solely on pain and psychological distress factors. The aim of the present study was to extend the assessment of CRFN efficacy by adding other outcome measures to shed light on neuromotor-functional-psychological interactions by undertaking comparison of pre- and 1-year postintervention data.

Methods

Forty patients with chronic whiplash injury–associated disorders were evaluated prior to and at two separate sessions after CRFN. The evaluation included Neck Disability Index, cervical range of motion, isometric cervical muscle strength, cervical pressure pain threshold, Symptom Check List–90-Revised, and subjective Self-Report of Improvement (SRI). The authors found that the CRFN had a significantly positive effect on all measured parameters. A case-by-case analysis revealed improvement in 70% of the patients at the final follow-up examination. Using stringent cutoff values, between 30 and 60% of the patients experienced measurable improvement. Evaluation of SRI results indicated that more than 80% of the patients were satisfied with the procedure.

Conclusions

Approximately 1 year after intervention, CRFN was associated with an acceptable rate of success, as reflected by objective and subjective outcome measures.
Head-turned rear impact causing dynamic cervical intervertebral foramen narrowing: implications for ganglion and nerve root injury
Authors: Tominaga Yasuhiro , Maak Travis G. , Ivancic Paul C. , Panjabi Manohar M. , Cunningham Bryan W.
Published: January 2008

Object

A rotated head posture at the time of vehicular rear impact has been correlated with a higher incidence and greater severity of chronic radicular symptoms than accidents occurring with the occupant facing forward. No studies have been conducted to quantify the dynamic changes in foramen dimensions during head-turned rear-impact collisions. The objectives of this study were to quantify the changes in foraminal width, height, and area during head-turned rear-impact collisions and to determine if dynamic narrowing causes potential cervical nerve root or ganglion impingement.

Methods

The authors subjected a whole cervical spine model with muscle force replication and a surrogate head to simulated head-turned rear impacts of 3.5, 5, 6.5, and 8 G following a noninjurious 2-G baseline acceleration. Continuous dynamic foraminal width, height, and area narrowing were recorded, and peaks were determined during each impact; these data were then statistically compared with those obtained at baseline.

The authors observed significant increases (p < 0.05) in mean peak foraminal width narrowing values greater than baseline values, of up to 1.8 mm in the left C5–6 foramen at 8 G. At the right C2–3 foramen, the mean peak dynamic foraminal height was significantly narrower than baseline when subjected to rear-impacts of 5 and 6.5 G, but no significant increases in foraminal area were observed. Analysis of the results indicated that the greatest potential for cervical ganglion compression injury existed at C5–6 and C6–7. Greater potential for ganglion compression injury existed at C3–4 and C4–5 during head-turned rear impact than during head-forward rear impact.

Conclusions

Extrapolation of present results indicated potential ganglion compression in patients with a non-stenotic foramen at C5–6 and C6–7; in patients with a stenotic foramen the injury risk greatly increases and spreads to include the C3–4 through C6–7 as well as C4–5 through C6–7 nerve roots.
Nonmissile penetrating spinal injury
Authors: Shahlaie Kiarash , Chang Dongwoo John , Anderson John T.
Published: January 2008

✓ Nonmissile penetrating spinal injuries (NMPSIs) are rare, even among the population of patients treated in large trauma centers. Patients who present with retained foreign body fragments due to stabbings represent an even smaller subset of NMPSI, and their optimal management is unclear.

The authors report the case of a 42-year-old man who presented to the University of California at Davis Medical Center with a retained knife blade after suffering a stab wound to the lower thoracic spine. They discuss this case in the context of a literature review and propose management options for patients with NMPSIs in whom fragments are retained.

A search of PubMed was undertaken for articles published between 1950 and 2006; the authors found 21 case reports and eight case series in the English-language literature but discovered no published guidelines on the management of cases of NMPSI with retained fragments.

After clinicians undertake appropriate initial trauma evaluation and resuscitation, they should obtain plain x-ray films and computerized tomography scans to delineate the anatomical details of the retained foreign body in relation to the stab wound. Neurosurgical consultation should be undertaken in all patients with an NMPSI, whether or not foreign body fragments are present. Surgical removal of a retained foreign body is generally recommended in these patients because the fragments may lead to a worse neurological outcome. Perioperative antibiotic therapy may be beneficial, but the result depends on the nature of the penetrating agent. There is no documentation in the literature to support the use of steroid agents in patients with NMPSIs.