bluuebunny/crossref_metadata_2025_split huggingface dataset:
Synovial cysts of the thoracic spine
Authors: Cohen-Gadol Aaron A. , White J. Bradley , Lynch James J. , Miller Gary M. , Krauss William E. 
Published: May 2009

Object.Thoracic synovial cysts (TSCs) are rare and are usually the subject of case reports. The authors studied the clinical manifestations, radiological aspects, and surgical treatment in a series of patients at their institution who harbored TSCs. They also review the literature to discuss the potential factors involved in the pathogenesis of this lesion.Methods.A database search of 16,000 patients who underwent decompressive spine surgery at the Mayo Clinic (Rochester, MN) between 1976 and 2003 disclosed nine patients (0.06%) in whom a diagnosis of TSC had been made. All patients were men. The mean age at presentation was 73 ± 5 years and mean duration of symptoms was 5 ± 3 months. The mean duration of follow up was 4 ± 3 years.The patients had no history of trauma or spine surgery. All patients had spastic paraparesis; two had urinary difficulties. Detailed neurological examination revealed myelopathy and radiculopathy with a sensory level of T10—L4. Magnetic resonance imaging revealed bilateral cysts in four patients and unilateral lesions in five. Three of the cysts were at the T-10 interspace, seven at the T-11 interspace, and three at the T-12 interspace. Seven cysts were on the right and six were on the left. Computerized tomography myelography performed in five patients revealed a gas bubble in the TSC in two patients. All patients underwent laminectomy/partial facetectomy, excision of the cyst, and decompression of the thecal sac and nerve root without any complications. None of these patients underwent a fusion. Eight patients (89%) experienced moderate to excellent relief of their preoperative signs and symptoms and one patient (11%) remained stable. There was no evidence of cyst recurrence at the site of surgery or other spinal segments at follow-up examination in any patient.Conclusions.When compared with their lumbar and cervical spine counterparts, TSCs are exceedingly rare. Their rarity may be explained by the decreased mobility of the thoracic spinal segments. The origin of TSCs is more likely degenerative rather than traumatic. Based on their experience and the follow-up duration, surgery provided durable relief from symptoms.
Surgical treatment of lumbosacral plexus injuries
Authors: Lang Eva Maria , Borges Jörg , Carlstedt Thomas 
Published: May 2009

Object. The purpose of this study was to analyze therapeutic possibilities and clinical outcomes in patients with lumbosacral plexus injuries to develop surgical concepts of treatment.
Methods. In a retrospective investigation 10 patients with injuries to the lumbosacral plexus were evaluated after surgery. The patients were assessed clinically, electrophysiologically, and based on the results of magnetic resonance imaging and computerized tomography myelography. In most patients a traction injury had occurred due to severe trauma that also caused pelvic fractures. In most cases the roots of the cauda equina of the lumbosacral plexus had ruptured. In cases of spinal root ruptures repair with nerve grafts were performed. In cases in which proximal stumps of the plexus could not be retrieved palliative nerve transfers by using lower intercostals nerves or fascicles from the femoral nerve were performed.
Conclusions. Lesions of the proximal spinal nerves and cauda equina occur in the most serious lumbosacral plexus injuries. Patients with such injuries subjected to reconstruction of spinal nerves, repair of ventral roots in the cauda equina, and nerve transfers recovered basic lower-extremity functions such as unsupported standing and walking.
Suspended laminoplasty for wide posterior cervical decompression and intradural access: results, advantages, and complications
Authors: Casha Steven , Engelbrecht H. Andries , DuPlessis Stephan J. , Hurlbert R. John 
Published: May 2009

Object.Cervical laminoplasty is a recognized technique commonly used for multilevel posterior cervical decompression, and it is favored over laminectomy for maintaining spinal stability. Traditional hinge techniques, however, limit lateral exposure on one side and can limit dural exposure. The authors present their experience with a modified laminoplasty technique incorporating complete laminectomy and placement of titanium miniplate instrumentation. This method allows wide bilateral posterior decompression and unobscured dural access.Methods.Twenty-eight patients (mean age 57 years) underwent cervical laminoplasty during a 4-year period. Twenty-seven patients presented with progressive cervical myelopathy. Seventeen patients (61%) had degenerative spondylotic stenosis; nine (32%) underwent resection of an intradural neoplasm. A mean of 3.5 levels were exposed and reconstructed. The follow-up period ranged from 4 months to 4 years (mean 15 months). The mean angular extension—flexion displacement measured between C-1 and C-7 was unchanged postoperatively, with preserved mobility across laminoplasty-treated segments in all patients. The anteroposterior diameter of the spinal canal increased 3.6 mm (27.2%) postoperatively (p = 0.004). In one patient an asymptomatic postoperative kyphosis developed. There were five cases of postoperative infection. One superficial infection resolved after intravenous antibiotic therapy alone, and four deep infections required surgical reexploration.Conclusions.The advantages of this technique over other laminoplasty methods include wide lateral spinal canal and intradural access, as well as preserved motion with partial restoration of the posterior tension band.
A biomechanical comparison of supplementary posterior translaminar facet and transfacetopedicular screw fixation after anterior lumbar interbody fusion
Authors: Kim Sung-Min , Lim T. Jesse , Paterno Josemaria , Kim Daniel H. 
Published: May 2009

Object. Facet screw fixation is the lowest profile lumbar stabilization method. In this study the immediate biomechanical stability provided by the two different types of fixation are compared: translaminar facet screw (TLFS) and transfacetopedicular screw (TFPS) placement after anterior lumbar interbody fusion (ALIF) using a femoral ring allograft. Both facet screw fixation types were also compared with the gold standard, transpedicular screw and rod (TSR) fixation.
Methods. Twenty-four human lumbosacral spines were tested in the following sequence: intact state, after discectomy, after ALIF, and after TLFS, TFPS, or TSR fixation. Intervertebral motions were measured by a video-based motion capture system. The range of motion (ROM) and neutral zone (NZ) were compared for each loading to a maximum of 7.5 Nm.
The ROMs for stand-alone ALIFs were less than but similar to those of the intact spine, but NZs were slightly increased in all modes. The ROMs for both TLFS and TFPS fixation were significantly decreased from those of the intact spine in all modes and those of the stand-alone ALIF in flexion and extension. The TLFS and TFPS fixations significantly reduced NZs to below that of the intact spine in all modes. Compared with NZs for ALIF, both types of fixation revealed significantly lower values, except for TLFS placement in lateral bending and TFPS fixation in lateral bending and rotation. There were no significant differences between TLFS and TFPS fixation. There were also no significant differences among both TLFS and TFPS and TSR fixations, except that TFPS was inferior to TSR in lateral bending.
Conclusions. Stand-alone ALIF may not provide sufficient stability. Both facet fixations produced significant additional stability and both are comparable to TSR fixation. Although TFPS fixation revealed a slightly inferior result, TFPSs can be placed percutaneously with the assistance of fluoroscopic guidance and it makes the posterior facet fixation minimally invasive. Therefore, the TFPS fixation can be considered as a good alternative to TLFS fixation.
A biomechanical comparison of three surgical approaches in bilateral subaxial cervical facet dislocation
Authors: Kim Sung-Min , Lim T. Jesse , Paterno Josemaria , Park Jon , Kim Daniel H. 
Published: May 2009

Object. In bilateral cervical facet dislocation, biomechanical stabilities between anterior locking screw/plate fixation after anterior cervical discectomy and fusion (ACDFP) and posterior transpedicular screw/rod fixation after anterior cervical discectomy and fusion (ACDFTP) have not been compared using the human cadaver, although ACDFP has been performed frequently. In this study the stability of ACDFP, a posterior wiring procedure after ACDFP (ACDFPW), and ACDFTP for treatment of bilateral cervical facet dislocation were compared.
Methods. Spines (C3—T1) from 10 human cadavers were tested in the intact state, and then after ACDFP, ACDFPW, and ACDFTP were performed. Intervertebral motion was measured using a video-based motion capture system. The range of motion (ROM) and neutral zone (NZ) were compared for each loading mode to a maximum of 2 Nm.
The ROM for spines treated with ACDFP was below that of the intact spine in all loading modes, with statistical significance in flexion and extension, but NZs were decreased in flexion and extension and slightly increased in bending and axial rotation; none of these showed statistical significance. The ACDFPW produced statistically significant additional stability in axial rotation ROM and in flexion NZ than ACDFP. The ACDFTP provided better stability than ACDFP in bending and axial rotation, and better stability than ACDFPW in bending for both ROM and NZ. There was no significant difference in extension with either ROM or NZ for the three fixation methods.
Conclusions. The spines treated with ACDFTP demonstrated the most effective stabilization, followed by those treated with ACDFPW, and then ACDFP. The spines receiving ACDFP also revealed a higher stability than the intact spine in most loading modes; thus ACDFP can also provide a relatively effective stabilization in bilateral cervical facet dislocation, but with the aid of a brace.
Cervical spinal cord delivery of a rabies G protein pseudotyped lentiviral vector in the SOD-1 transgenic mouse
Authors: Tanase Kiana , Teng Qingshan , Krishnaney Ajit A. , Liu James K. , Garrity-Moses Mary E. , Boulis Nicholas M. 
Published: May 2009

Object. Lentiviral vectors may constitute a vehicle for long-term therapeutic gene expression in the spinal cord. In amyotrophic lateral sclerosis, spinal cord sclerosis and altered axonal transport pose barriers to therapeutic gene distribution. In the present study the authors characterize gene expression distribution and the behavioral impact of the rabies G (RabG) protein pseudotyped lentiviral vector EIAV.LacZ through cervical spinal cord injection in control and Cu/Zn superoxide dismutase—1 (SOD-1) transgenic mice.
Methods. Seven-week-old SOD-1 transgenic mice and their wild-type littermates underwent exposure of the cervicomedullary junction and microinjection of RabG.EIAV.LacZ or vehicle. The Basso-Beattie-Bresnahan locomotor score, grip strength meter, and Rotarod assays were used to assess the effects of disease progression, spinal cord microinjection, and lentiviral gene expression. Spinal cords were removed when the mice were in the terminal stage of the disease. The distribution of LacZ gene expression was histologically evaluated and quantified.
Direct cervical spinal cord microinjection of RabG.EIAV.LacZ results in extensive central nervous system uptake in SOD-1 transgenic mice; these findings were statistically similar to those in wild-type mice (p > 0.05). Gene expression lasts for the duration of the animal's survival (132 days). The SOD-1 mutation does not prevent retrograde axonal transport of the vector. Three behavioral assays were used to demonstrate that long-term gene expression does not alter sensorimotor function. In comparison with normative data, vector injection and transgene expression do not accelerate disease progression.
Conclusions. Direct spinal cord injection of RabG.EIAV vectors represents a feasible method for delivering therapeutic genes to upper cervical spinal cord and brainstem motor neurons. Distribution is not affected by the SOD-1 mutation or disease phenotype.
The future in the care of the cervical spine: interbody fusion and arthroplasty
Authors: Mummaneni Praveen V. , Haid Regis W. 
Published: May 2009

✓ In the past 50 years tremendous advances have been made in the treatment of cervical disc disease with cervical fusion. Fusion rates have surpassed 95% after application of anterior cervical implants. Adjacent-segment degeneration, however, has plagued the long-term clinical success of cervical fusion.
Cervical arthroplasty has been introduced to maintain cervical motion and potentially avoid or minimize adjacent-segment degeneration. If cervical arthroplasty is successful, the long-term results of surgery for cervical disc disease may improve; however, there are associated drawbacks that must be overcome. Implant wear, fatigue, and failure have been reported in cases of large-joint arthroplasty, and research is underway to limit these problems in cervical arthroplasty.
In this article the authors trace the evolution of cervical fusion and the new technique of cervical arthroplasty. The nomenclature of cervical arthroplasty will also be introduced.
Does chronic cervical myelopathy affect respiratory function?
Authors: Toyoda Hiromitsu , Nakamura Hiroaki , Konishi Sadahiko , Terai Hidetomi , Takaoka Kunio 
Published: May 2009

Object. Although respiratory function is often impaired by acute cervical spinal cord injury, changes in respiratory function in patients with chronic cervical myelopathy (CCM) are not well documented. The purpose of this study was to evaluate the respiratory function of patients with CCM.
Methods. Spirometric parameters were measured in 94 patients with CCM before they underwent expansive laminoplasty. These measurements were compared with those obtained in age- and sex-matched control group patients without myelopathy. The study patients were also subdivided into two groups: those with spinal compressive lesions above or below the C3–4 disc level were compared in terms of respiratory function.
The vital capacity values measured in patients with CCM were significantly lower than those in the control group. In patients in whom spinal cord compression was present above C3–4, vital capacity values were lower than in patients in whom the compression level was below C3–4. The resting respiratory rate per minute was elevated in the CCM group. Peak expiratory flow rate was significantly decreased, and expiratory velocities at 50 and 25% of vital capacity were significantly increased in the CCM group.
Conclusions. The results indicated that expiratory flow may be impaired or incomplete in patients with CCM. An underlying subclinical respiratory dysfunction appears to be associated with CCM.
Insertion torque and pullout force of rescue screws for anterior cervical plate fixation in a fatigued initial pilot hole
Authors: Pitzen Tobias , Franta Frederick , Barbier Dragos , Steudel Wolf-Ingo 
Published: May 2009

Object.The purpose of this study was to investigate whether thicker-core-diameter screws increase fixation strength in the cervical spine.Methods.Bone mineral density (BMD) was determined for each vertebral body (VB) obtained in six human C4–7 segments. Based on their BMD, the specimens were assigned to one of two groups in which torque and pullout force were tested. Two initial pilot holes were drilled into the VBs and tests were first performed using a standard screw. The test was repeated using a thicker rescue screw inserted into the same initial pilot hole. The mean value of peak torque and pullout force resulting from the single left/right measurements was used for statistical analysis. A t-test was performed to determine the effect of screw design on peak torque and pullout force. Moment correlation coefficients were calculated to determine the effect of BMD on peak torque and pullout force.Mean insertional peak torque for the standard screw was 82.1 N/cm and that for the rescue screw was 47.6 Ncm (p < 0.001). There was a strong correlation between insertional peak torque and BMD for both standard screws (r = 0.71, p = 0.02) and rescue screws (r = 0.59, p = 0.07). The mean pullout force for standard screws was 464.7 N, whereas it was 164.5 N for rescue screws (p < 0.001). There was a strong correlation between pullout force and BMD for both standard (r = 0.75, p = 0.0081) and rescue screws (r = 0.7, p = 0.025).Conclusions.Uncemented rescue screws that have been inserted into a fatigued hole in the cervical VB do not strengthen the screw—bone interface compared with the strength initially conferred by a standard screw.
A comparison of simulator-tested and -retrieved cervical disc prostheses
Authors: Anderson Paul A. , Rouleau Jeffrey P. , Toth Jeffrey M. , Riew K. Daniel 
Published: May 2009

Object. Total joint arthroplasties most commonly fail because the implant becomes worn and a host inflammatory response subsequently develops. Both the material response to the biological environment and the host response to the device must be thoroughly evaluated to establish the efficacy of cervical arthroplasty. Analyses of devices explanted in humans allow evaluation of both responses. Hypothetical wear rates can be determined by comparing in vivo wear with simulator-derived wear. The purpose of this study was to perform explant analyses involving the Bryan and Prestige discs and compare these results with those obtained using spine simulators.
Methods. Of the approximately 5500 patients treated with the Bryan disc, 11 have undergone explantation of the device. Six of these devices were analyzed for dimensional and chemical changes. Three of the approximately 300 implanted Prestige discs were retrieved, and two were examined microscopically. Histological specimens were assessed for wear particles and host inflammatory response. Additionally, the extent of simulator-produced wear was compared with that demonstrated in the retrieved specimens.
Conclusions. The simulator-generated results predict adequate wear-related characteristics for both the Bryan and Prestige prostheses for a minimum of 40 years. Comparison of data with those of the retrieved specimens indicates that the wear was more minimal than predicted in simulators by five- to 10-fold. In no instance did the revisions result from failure of the device due to a reaction to wear debris, fracture, polymer oxidation, or metal corrosion. The inflammatory response seen in the periprosthetic tissues was minimal and not characteristic of inflammatory responses in failed diarthrodial joint arthroplasties.
Prospective outcomes evaluation after decompression with or without instrumented fusion for lumbar stenosis and degenerative Grade I spondylolisthesis
Authors: Ghogawala Zoher , Benzel Edward C. , Amin-Hanjani Sepideh , Barker Fred G. , Harrington J. Fred , Magge Subu N. , Strugar John , Coumans Jean-Valéry C.E. , Borges Lawrence F. 
Published: May 2009

Object. There is considerable debate among spine surgeons regarding whether fusion should be used to augment decompressive surgery in patients with symptomatic lumbar spinal stenosis involving Grade I degenerative spondylolisthesis. The authors prospectively evaluated the outcomes of patients treated between 2000 and 2002 at two institutions to determine whether fusion improves functional outcome 1 year after surgery.
Methods. Patients ranged in age from 50 to 81 years. They presented with degenerative Grade I (3- to 14-mm) spondylolisthesis and lumbar stenosis without gross instability (< 3 mm of motion at the level of subluxation). Those in whom previous surgery had been performed at the level of subluxation were excluded. Each patient completed Oswestry Disability Index (ODI) and Short Form—36 (SF-36) questionnaires preoperatively and at 6 to 12 months postoperatively.
Some patients underwent decompression alone (20 cases), whereas others underwent decompression and posterolateral instrumentation-assisted fusion (14 cases), at the treating surgeon's discretion. Baseline demographic data, radiographic features, and ODI and SF-36 scores were similar in both groups. The 1-year fusion rate was 93%.
Both forms of surgery independently improved outcome compared with baseline status, based on ODI and SF-36 physical component summary (PCS) results (p < 0.001). Decompression combined with fusion led to an improvement in ODI scores of 27.5 points, whereas decompression alone was associated with a 13.6-point increase (p = 0.02). Analysis of the SF-36 PCS data also demonstrated a significant intergroup difference (p = 0.003).
Conclusions. Surgery substantially improved 1-year outcomes based on established outcomes instruments in patients with Grade I spondylolisthesis and stenosis. Fusion was associated with greater functional improvement.
Treatment of basilar invagination by atlantoaxial joint distraction and direct lateral mass fixation
Authors: Goel Atul 
Published: May 2009

Object. The author discusses the successful preliminary experience of treating selected cases of basilar invagination by performing atlantoaxial joint distraction, reduction of the basilar invagination, and direct lateral mass atlantoaxial plate/screw fixation.
Methods. Twenty-two patients with basilar invagination—in which the odontoid process invaginated into the foramen magnum and the tip of the odontoid process was above the Chamberlain, McRae foramen magnum, and Wackenheim clival lines—were selected to undergo surgery. In all patients fixed atlantoaxial dislocations were documented.
The 16 male and six female patients ranged in age from 8 to 50 years. A history of trauma prior to the onset of symptoms was documented in 17 patients. Following surgery, the author observed minimal-to-significant reduction of basilar invagination and alteration in other craniospinal parameters resulting in restoration of alignment of the tip of the odontoid process and the clivus and the entire craniovertebral junction in all patients. In addition to neurological and radiological improvement, preoperative symptoms of torticollis resolved significantly in all patients. The minimum follow-up period was 12 months and the mean was 28 months.
Conclusions. Joint distraction and firm lateral mass fixation in selected cases of basilar invagination is a reasonable surgical treatment for reducing the basilar invagination, restoring craniospinal alignment, and establishing fixation of the atlantoaxial joint.
The V2 segment of the vertebral artery and its branches
Authors: Özgen Serdar , Pait T. Glenn , ÇağLar Y. Şsükrü 
Published: May 2009

Object.The goal of this study was to demonstrate the origins, courses, anastomoses, and target tissues of the arterial branches that arise from the V2segment of the vertebral artery.Methods.Ten adult cadaveric necks (20 V2segment specimens) were examined (magnification × 40) after injection of colored silicon. The branches at each cervical level were classified in a new system according to anatomical features and target tissues—anterior, posterior, medial, and lateral. Incidence with which each branch category was observed at each cervical level was calculated.Anterior branches were observed at C-3 in all 20 V2segment specimens. The incidence with which the posterior branch was present at C-4 was 45%, whereas the corresponding rates at segments superior and inferior were lower. The medial V2segment branches were assessed in four subcategories. The anterior spinal artery was present at C-3 in all specimens, whereas the mean incidence at the C4–6 level was 46.7%. The posterior spinal artery was most frequently detected at C-3 (60%). The anterior radicular artery (RA) was present at C-5 in 50% of the specimens, whereas the posterior RA was detected at C-5 in only 35%. Lateral branches were most frequently detected at C-3.Conclusions.The authors provide detailed anatomical information about the origins, courses, anastomoses, and target tissues of the vessels that arise from the V2segment. This new classification allows for better understanding of the vasculature of the C3–6 region.