bluuebunny/crossref_metadata_2025_split huggingface dataset:
Comparison of CD HORIZON SPIRE spinous process plate stabilization and pedicle screw fixation after anterior lumbar interbody fusion
Authors: Wang Jeremy C. , Haid Regis W. , Miller Jay S. , Robinson James C. 
Published: January 2008

Object
The authors present the early clinical results obtained in patients who underwent SPIRE spinous process plate fixation following anterior lumbar interbody fusion (ALIF).

Methods
Between May 2003 and January 2005, 32 patients underwent titanium cage and bone morphogenetic protein–augmented ALIF and subsequent SPIRE (21 cases) or bilateral pedicle screw (BPS; 11 cases) fixation. Pedicle screws were implanted using either the open approach (three cases) or using a tubular retractor (eight cases). Patients’ charts were reviewed for operative time, estimated blood loss (EBL), hospital length of stay (LOS), and evidence of pseudarthrosis or hardware failure.
In SPIRE plate–treated patients, the median EBL (75 ml) was lower than in BPS-treated patients (open BPS [150 ml]; tubular BPS [125 ml]). The median operative time in SPIRE plate–treated patients was also shorter (164 minutes compared with 239 and 250 minutes in the open and tubular BPS, respectively). The median LOS was 3 days for both the SPIRE and tubular BPS groups, but 4 days in the open BPS group. There were no instances of major surgery-induced complication, pseudarthrosis, or hardware failure during mean follow-up periods of 5.5, 7.2, and 4.9 months in the SPIRE, open PS, and tubular BPS groups, respectively.

Conclusions
The SPIRE plate is easy to implant and is associated with minimal operative risk. Compared with BPS/rod constructs, SPIRE plate fixation leads to less EBL and shorter operative time, without an increase in the rate of pseudarthrosis. Hospital LOS was also shorter in SPIRE plate–treated patients, which is consistent with the goals of minimal access spinal technologies.
Modulation of nitric oxide homeostasis in a mouse model of spinal cord injury
Authors: Genovese Tiziana , Mazzon Emanuela , Mariotto Sofia , Menegazzi Marta , Cardali Salvatore , Conti Alfredo , Suzuki Hisanori , Bramanti Placido , Cuzzocrea Salvatore 
Published: January 2008

ObjectA traumatic spinal cord injury (SCI) immediately induces primary damage, and this is followed by secondary damage characterized by a series of events among which is a progressive extension of cell death within the damaged tissue. In this study, the authors investigated the role of inducible nitric oxide synthase (iNOS) in an experimental model of SCI in mice.MethodsIn wild-type (iNOS+/+) mice, SCI rapidly induced an inflammatory response as shown by nitrotyrosine formation, activation of the nuclear enzyme poly(adenosine diphosphate-ribose) polymerase (PARP), neutrophil infiltration, and spinal cord tissue histopathological changes, indicating the involvement of iNOS-derived massive amounts of NO in SCI.ConclusionsGenetic inhibition of iNOS, however, resulted in a significant reduction in secondary damage, and this therapeutic efficacy was associated with the prevention of an SCI-induced drop in neuronal and endothelial NOS activity.
Biomechanical study of thoracolumbar junction fixation devices with different diameter dual-rod systems
Authors: Chang Ung-Kyu , Lim Jesse , Kim Daniel H. 
Published: January 2008

Object
Advances in the design of a smaller-diameter rod system for use in the thoracolumbar region prompted the authors to undertake this biomechanical study of two different thoracolumbar implants.

Methods
In vitro biomechanical testing was performed using human cadaveric spines. All specimens were loaded to a maximum moment of 5 Nm with 300-N axial preload in six modes of motion. Two types of anterior implants with different rod diameters were applied to intact T10–12 specimens in two groups. The loading was repeated and the range of motion (ROM) was measured. A T-11 corpectomy was then performed and a strain gauge–mounted carbon fiber stackable cage was implanted. The ROM and compression force on the cage were measured, and the mean values were compared between these two groups.
With stabilization of the intact spine, ROM decreased least in extension and greatest in bending compared with the intact specimens. After corpectomy and stabilization, ROM increased in extension by 104.89 ± 53.09% in specimens with a 6.35-mm rod insertion and by 83.81 ± 16.96% in those with a 5.5-mm rod, respectively; in flexion, ROM decreased by 26.98 ± 27.43% (6.35 mm) and by 9.59 ± 15.42% (5.5 mm), respectively; and in bending and rotation, both groups each showed a decrease in ROM. The load sharing of the cage was similar between the two groups (the 6.35-mm compared with 5.5-mm rods): 47.44 and 44.73% (neutral), 49.16 and 39.02% (extension), 61.90 and 56.88% (flexion), respectively.

Conclusions
There were no statistical differences in the ROM and load sharing of the cage when either the 6.35-or 5.5-mm-diameter dual-rod was used.
Biomechanical evaluation of the ventral and lateral surface shear strain distributions in central compared with dorsolateral placement of cages for lumbar interbody fusion
Authors: Sohn Moon-Jun , Kayanja Mark M. , Kilinçer Cumhur , Ferrara Lisa A. , Benzel Edward C. 
Published: January 2008

Object
The purpose of this study was to measure and compare the ventral and lateral surface strain distributions and stiffness for two types of interbody cage placement: 1) central placement for anterior lumbar interbody fusion (ALIF); and 2) dorsolateral placement for extraforaminal lumbar interbody fusion (ELIF).

Methods
Two functional spine units were obtained for testing in each of 13 cadaveric spines, yielding 26 segments (three of which were not used because of bone abnormalities). Bilateral strain gauges were mounted adjacent to the endplate on the lateral and ventral walls of each vertebral body in the 23 motion segments. Each segment was cyclically tested in compression, flexion, and extension in the following conditions: while intact, postdiscectomy, and instrumented with interbody fusion cages placed using both insertion techniques.
No significant differences were observed between ALIF and ELIF in compressive stiffness, bending stiffness in flexion and extension (p ≥ 0.1), ventral and lateral strain distribution during the intact tests (p ≥ 0.24), and during the flexion tests after fusion (p ≥ 0.22). In compression, higher ventral and lower lateral strain was observed in the ALIF than in the ELIF group (ventral, p = 0.05; lateral, p = 0.04), and in extension, higher ventral (p = 0.01) and higher lateral strain (p = 0.002) was observed in the ELIF than in the ALIF group.

Conclusions
Preservation of the ventral anulus and dorsolateral placement of the interbody cages during ELIF allow alternate load transfer pathways through the dorsolateral vertebral wall and ventral anulus that are not observed following ALIF. These may be associated with a lower incidence of subsidence and a higher rate of fusion due to a more concentrated application of bone healing–enhancing compression forces during the fusion and healing process.
Implantation of an empty carbon fiber cage or a tricortical iliac crest autograft after cervical discectomy for single-level disc herniation: a prospective comparative study
Authors: Schils Frédéric , Rilliet Benedict , Payer Michael 
Published: January 2008

Object
The authors conducted a study to evaluate and compare prospectively the implantation of either an empty carbon fiber composite frame cage (CFCFC) or an iliac crest autograft after anterior cervical discectomy (ACD) for cervical disc herniation with monoradiculopathy.

Methods
Thirty-six consecutive patients with one-level radiculopathy due to single-level cervical disc herniation were treated by ACD, and implantation of either an empty CFCFC (24 patients) or an iliac crest autograft (12 patients). Radiological and clinical assessments were performed preoperatively, immediately postoperatively; and at 3, 6, and 12 months postoperatively. Fusion, at the 12-month follow-up examination was demonstrated in 96% of the patients in the cage group and in 100% of those in the autograft group. The mean anterior intervertebral body height was 3.7 mm preoperatively and 3.9 mm at 12 months in the CFCFC, and 4.1 and 3.8 mm, respectively, in the autograft group. In cage-treated patients, neck pain, as measured using the visual analog scale (VAS) (Score 0 = minimum; 10 = maximum) decreased from 6.4 preoperatively to 2.0 at 12 months, and radicular pain, decreased from 8.4 preoperatively to 1.5 at 12 months. In the autograft group, neck pain changed from a mean preoperative VAS score of 7.2 to 2.5 at 12 months, and radicular pain decreased from a preoperative mean of 7.8 to 1.4 at 12 months. Analysis of the 12-Item Short Form Health Survey domains and the Oswestry Disability Index scores indicated a significant improvement in both the Physical and Mental Component Summary domains in both groups.

Conclusions
Implantation of an empty CFCFC or a tricortical iliac crest autograft after ACD are safe and reliable options for the treatment of cervical disc herniation causing one-sided radiculopathy. Both procedures produced equally satisfying clinical and radiological results, leading to a high fusion rate and maintaining intervertebral height. Implantation of an empty CFCFC has the advantages of avoiding any donor site morbidity and requiring a significantly shorter operative time.
Anterior expandable strut cage replacement for osteoporotic thoracolumbar vertebral collapse
Authors: Uchida Kenzo , Kobayashi Shigeru , Nakajima Hideaki , Kokubo Yasuo , Yayama Takafumi , Sato Ryuichiro , Timbihurira Godfrey , Baba Hisatoshi 
Published: January 2008

ObjectThe authors investigated the usefulness of using an expandable cage strut in anterior reconstruction after osteoporotic vertebral collapse in patients with neurological deficits.MethodsTwenty-eight patients who had undergone expandable cage strut–augmented anterior thoracolumbar reconstruction participated in a follow-up review for a mean of 4.9 years. Radiographs were reviewed for kyphosis, lateral tilt of the implant, cage subsidence, the presence of a solid fusion mass, and instrumentation failure. Changes in neurological status and visual analog scale (VAS) pain score, as well as technique-related complications, were examined.The mean angles ± the standard deviations of kyphosis correction 4 to 6 weeks after surgery and at final follow-up examination were 10.4 ± 7.6° and 5.6 ± 6.0°, respectively. The mean subsidence of the expandable cage within the adjacent vertebrae was 2.5 ± 3.0 mm at the final follow-up examination. Neurological improvement at the final follow up was more significant in patients with Type 1 (wedge-type) than Type 2 (flat-type) (p = 0.037) or Type 3 (concave-type) (p = 0.006) vertebral collapse. Follow-up VAS scores were significantly higher in patients with Type 1 than Type 3 collapse (p = 0.012). In all cases the authors observed solid union with incorporation of the cage. There were no surgery-related complications.ConclusionsAn expandable titanium cage strut seems useful in vertebral body replacement in patients with osteoporotic thoracolumbar collapse. Favorable results were obtained in cases of Type 1 collapse (wedge type) in which the middle and posterior columns remained comparatively intact.
Anatomical considerations for cervical pedicle screw insertion: the use of multiplanar computerized tomography reconstruction measurements
Authors: Chazono Masaaki , Soshi Shigeru , Inoue Takeshi , Kida Yoshikuni , Ushiku Chikara 
Published: January 2008

Object
The purpose of this study was to evaluate the linear and angular parameters of the vertebral body (VB) required for cervical pedicle screw (CPS) insertion by using multiplanar computerized tomography (CT) reconstructions.

Methods
Three hundred fifteen vertebrae from C-3 to C-7 in 63 patients were studied. Pedicle dimensions such as pedicle transverse angle (PTA), pedicle sagittal angle (PSA), and pedicle outer width (POW) were measured on axial CT reconstructions, as were linear parameters including the lateral mass thickness (LMT), the anteroposterior (AP) and mediolateral distances between spinal canal and transverse foramen, and spinal canal longitudinal and transverse diameter. In addition, the correlations between PTA and other parameters were calculated using univariate linear regression analysis.
The overall mean LMT ranged from 10.7 to 12.6 mm. The smallest mean AP spinal canal–transverse foramen distance was found at C-7 (1.1 mm),whereas the largest mean distance was at C-4 (3.1 mm). The smallest mean mediolateral spinal canal–transverse foramen distance was found at C-4 (1.2 mm), whereas the largest mean distance was at C-7 (4.7 mm). There were significant intergroup differences between male and female patients except for PTA and spinal canal longitudinal diameter. The PTA had a direct linear correlation with AP and mediolateral spinal canal–transverse foramen distances. The largest Pearson coefficient was 0.71 between the PTA and AP spinal canal–transverse foramen distance and the inverse one was −0.73 between the PTA and mediolateral spinal canal–transverse foramen distance.

Conclusions
Analysis of the data obtained in this study suggests that not only pedicle dimensions but also linear and angular parameters of the VB can be useful data when inserting a CPS.
Complications of halo fixation in the elderly
Authors: Horn Eric M. , Theodore Nicholas , Feiz-Erfan Iman , Lekovic Gregory P. , Dickman Curtis A. , Sonntag Volker K. H. 
Published: January 2008

Object
The risk factors of halo fixation in elderly patients have never been analyzed. The authors therefore retrospectively reviewed data obtained in the treatment of such cases.

Methods
A discharge database was searched for patients 70 years of age or older who had undergone placement of a halo device. In a search of cases managed between April 1999 and February 2005, data pertaining to 53 patients (mean age 79.9 years [range 70–97 years]) met these criteria. Forty-one patients were treated for traumatic injuries. Ten patients had deficits ranging from radiculopathy to quadriparesis, and 43 had no neurological deficit. Adequate follow-up material was available in 42 patients (mean treatment duration 91 days). Halo immobilization was the only treatment in 21 patients, and adjunctive surgical fixation was undertaken in the other 21 patients. There were 31 complications in 22 patients: respiratory distress in four patients, dysphagia in six, and pin-related complications in 10. Eight patients died; in two of these cases, the cause of death was clearly unrelated to the halo brace. The other six patients died of respiratory failure and cardiovascular collapse (perioperative mortality rate 14%). Three patients who died had sustained acute trauma and three had undergone surgical stabilization.

Conclusions
External halo fixation can be used safely to treat cervical instability in elderly patients. The high complication rate in this population may reflect the significant incidence of underlying disease processes.
Biomechanical study on the effect of five different lumbar reconstruction techniques on adjacent-level intradiscal pressure and lamina strain
Authors: Sudo Hideki , Oda Itaru , Abumi Kuniyoshi , Ito Manabu , Kotani Yoshihisa , Minami Akio 
Published: January 2008

Object
The objectives of this study were to compare the biomechanical effects of five lumbar reconstruction models on the adjacent segment and to analyze the effects of three factors: construct stiffness, sagittal alignment, and the number of fused segments.

Methods
Nondestructive flexion–extension tests were performed by applying pure moments to 10 calf spinal (L3–S1) specimens. One-segment (L5–6) or two-segment (L5–S1) posterior fusion methods were simulated: 1) one-segment posterolateral fusion (PLF); 2) one-segment PLF with interbody fusion cages (one-segment PLIF/PLF); 3) two-segment PLF; 4) two-segment PLIF/PLF; and 5) two-segment PLF in kyphosis (two-segment kyphotic PLF). The range of motion (ROM) of the reconstructed segments, intradiscal pressure (IDP), and lamina strain in the upper (L4–5) adjacent segment were analyzed.
The ROM was significantly decreased in the PLIF/PLF models compared with that in the PLF alone models after both the one- and two-segment fusions. If the number of fused segments was increased, the pressure and strains were also increased in specimens subjected to the PLIF/PLF procedure, more so than the PLF-alone procedure. In the one-segment PLIF/PLF model the authors observed a reduced IDP and lamina strain compared with those in the kyphotic two-segment PLF model despite the latter’s higher levels of initial stiffness.

Conclusions
If the number of fused levels can be reduced by using PLIF to correct local kyphosis, then this procedure may be valuable for reducing adjacent-segment degenerative changes.
Symptomatic pneumorachis associated with incidental durotomy during microscopic lumbar disc surgery
Authors: Rovlias Aristedis , Pavlakis Emmanuel , Kotsou Serafim 
Published: January 2008

✓ Unintended incidental durotomy is not a rare complication of lumbar microsurgery and is usually recognized and treated immediately. The reconstruction process can be complicated further by unpredictable factors. To their knowledge, the authors report the first case of a symptomatic pneumorachis associated with the accidental awakening of a patient during reconstruction of an incidental durotomy following lumbar microdiscectomy.
Incomplete cauda equina syndrome developed in the patient on awakening from surgery after reconstruction of an unintended incidental dural tear that occurred during lumbar microdiscectomy. Symptomatic pneumorachis was revealed on an emergency computed tomography scan, and the patient underwent immediate repeated operation to remove air and decompress the spinal canal.
The increasing number and complexity of surgical procedures in the lumbar spine contribute to the growing incidence of unintended durotomy. The surgeon should be aware of rare complications that may arise. Development of a vacuum phenomenon in conjunction with a ball–valve mechanism may lead to pneumorachis during durotomy repair. If this rare complication is promptly recognized and confronted, the outcome will not be associated with long-term sequelae.
Percutaneous vertebroplasty of a myelomatous compression fracture in the presence of previous posterior instrumentation
Authors: Chakrabarti Indro , Burton Allen W. , Rao Ganesh , Feiz-Erfan Iman , Hlatky Roman , Rhines Laurence D. , Mendel Ehud 
Published: January 2008

✓ The authors report the use of percutaneous transpedicular vertebroplasty performed using polymethylmethacrylate (PMMA) in two patients. These men (53 and 57 years old) had previously undergone open surgery and posterior instrumentation to treat myelomatous compression fractures. Both patients presented with acute back pain that manifested after minor activities. Kyphotic wedge fractures were diagnosed at T-11 in one case and at L-1 in the other. Both patients were treated at other hospitals with laminectomy and instrumented fusion; multiple myeloma was diagnosed after surgery. The patients experienced severe, recalcitrant, and progressive pain; on referral, they were found to have persistent kyphosis. Multiple myelomatous lesions of the spine were seen in one case and in the other the L-1 fracture represented the only site of disease. Percutaneous vertebroplasty was performed by injecting PMMA into the anterior third of the compressed vertebral body. Both patients experienced a 50% reduction in pain immediately after treatment; 3 months later both were walking and reported minimal back pain while undergoing treatment for multiple myeloma. Three years after surgery one patient reported no back pain and no progressive instability of the spine. Four years after surgery the other patient remains pain free, ambulatory, and with overall disease remission.
Percutaneous vertebroplasty provided effective analgesia in these two patients with progressive back pain despite posterior stabilization. In both cases, the anterior column was effectively stabilized. A much larger operative intervention with its attendant risks of morbidity was avoided. In addition, subsequent aggressive medical treatment was well tolerated.
Repetitive tensile stress to rat caudal vertebrae inducing cartilage formation in the spinal ligaments: a possible role of mechanical stress in the development of ossification of the spinal ligaments
Authors: Tsukamoto Nobuaki , Maeda Takeshi , Miura Hiromasa , Jingushi Seiya , Hosokawa Akira , Harimaya Katsumi , Higaki Hidehiko , Kurata Kousaku , Iwamoto Yukihide 
Published: January 2008

Object
Mechanical stress has been considered one of the important factors in ossification of the spinal ligaments. According to previous clinical and in vitro studies, the accumulation of tensile stress to these ligaments may be responsible for ligament ossification. To elucidate the relationship between such mechanical stress and the development of ossification of the spinal ligaments, the authors established an animal experimental model in which the in vivo response of the spinal ligaments to direct repetitive tensile loading could be observed.

Methods
The caudal vertebrae of adult Wistar rats were studied. After creating a novel stimulating apparatus, cyclic tensile force was loaded to rat caudal spinal ligaments at 10 N in 600 to 1800 cycles per day for up to 2 weeks. The morphological responses were then evaluated histologically and immunohistochemically.
After the loadings, ectopic cartilaginous formations surrounded by proliferating round cells were observed near the insertion of the spinal ligaments. Several areas of the cartilaginous tissue were accompanied by woven bone. Bone morphogenetic protein–2 expression was clearly observed in the cytoplasm of the proliferating round cells. The histological features of the rat spinal ligaments induced by the tensile loadings resembled those of spinal ligament ossification observed in humans.

Conclusions
The findings obtained in the present study strongly suggest that repetitive tensile stress to the spinal ligaments is one of the important causes of ligament ossification in the spine.