Ultrasonic Bone Scalpel versus Conventional Technique for Thoracolumbar Spinal Decompression: A Prospective Randomized Controlled Trial / Bisturi ósseo ultrassônico versus técnica convencional para descompressão espinhal torácica: Um teste controlado randomizado prospectivo

Abstract Objective The purpose of the present study is to compare intraoperative blood loss, operating time, laminectomy time, hospital length of stay, and complications in thoracolumbar spinal decompression using ultrasonic bone scalpels (UBSs) with conventional procedures. Methods Forty-two patients who underwent decompressive laminectomy and pedicular screw fusion with a surgical level of 1-5 levels between February 1, 2020, and June 30, 2022, in a single institution were evaluated for eligibility, and 11 were excluded due to a history of spinal surgery (n= 3), spinal tumor (n= 3), and spinal infection (n= 5). A total of 31 patients were randomly divided into the UBS group (n =15) and the conventional group (n =16). Intraoperative blood loss, operating time, laminectomy time, hospital length of stay, and complications were recorded. Results Intraoperative blood loss and laminectomy time were significantly lower in the UBS group (656.0 ± 167.6 ml, 54.5 ± 27.4 minutes, respectively) than in the conventional group (936.9 ± 413.2 ml, 73.4 ± 28.1 minutes, respectively). Overall operation time, hospital length of stay, and complications were all similar between the groups. Conclusion The UBS is a useful instrument for procedures performed near the dura mater or other neural tissue without excessive heat or mechanical injury. This device is recommended for various spinal surgeries in addition to high-speed burrs and Kerrison rongeurs.

Resumo Objetivo O objetivo do presente estudo é comparar perda de sangue intraoperatória, tempo de operação, tempo de laminectomia, tempo de internação hospitalar e complicações na descompressão espinhal torácica utilizando bisturis ósseos ultrassônicos (BOUs) em relação aos procedimentos convencionais. Métodos Quarenta e dois pacientes submetidos a laminectomia descompressiva e fusão pedicular do parafuso com um nível cirúrgico de 1 a 5, entre 1° de fevereiro de 2020 e 30 de junho de 2022 em uma única instituição, foram avaliados para elegibilidade e 11 foram excluídos devido ao histórico de cirurgia espinhal (n= 3), tumor espinhal (n= 3) e infecção espinhal (n= 5). Perda de sangue intraoperatória, tempo de operação, tempo de laminectomia, tempo de internação e complicações foram registradas. Resultados A perda de sangue intraoperatória e o tempo de laminectomia foram significativamente menores no grupo BOU (656,0 ± 167,6 ml, 54,5 ± 27,4 min, respectivamente) do que no grupo convencional (936,9 ± 413,2 ml, 73,4 ± 28,1 min, respectivamente). O tempo de funcionamento total, o tempo de internação e as complicações foram todos semelhantes entre os grupos. Conclusão O bisturi ósseo ultrassônico é um instrumento útil para procedimentos realizados próximos à dura-máter ou outro tecido neural sem calor excessivo ou lesão mecânica. Este dispositivo é recomendado para várias cirurgias de coluna vertebral, juntamente com rebarbas de alta velocidade e pinça Kerrison.

Effect of morphological changes in the sagittal plane of vertebrae and discs on degenerative kyphodeformity / 中国骨伤

OBJECTIVE@#To explore the effects of morphological changes such as vertebral wedge deformation and disc degeneration (collapse) on adult thoracolumbar/lumbar degenerative kyphosis(TL/LDK) deformity.@*METHODS@#A retrospective analysis of 32 patients with spinal TL/LDK deformity admitted from August 2015 to December 2020, including 8 males and 24 females, aged 48 to 75(60.3±12.4) years old. On the long-cassette standing upright lateral radiographs, the coronal Cobb angle, sagittal thoracic lumbar/lumbar kyphosis angle(KA) of spine were measured, and the height and wedge parameters of apex vertebral(AV) and two vertebrae(AV-1, AV-2, AV+1, AV+2) above and below AV and the intervertebrae and the intervertebral disc(AV-1D, AV-2D, AV+1D, AV+2D) were evaluated, involving anterior vertebral body height(AVH), posterior vertebral body height(PVH), vertebral wedge angle(VWA), ratio of vertebral wedging(RVW), anterior disc height(ADH), posterior disc height(PDH), disc wedge angle(DWA), ratio of disc wedging(RDW), and DWA/KA.@*RESULTS@#The average angle of kyphosis was (44.2±19.1)°. A significant decrease in anterior height of vertebral was observed compared to the posterior height of vertebral(P<0.005). There was no significant difference in anterior and posterior height of discs. The vertebral wedging ratio/contribution ratio:AV-2(14.98±10.95)%/(14.21±8.08)%, AV-1(21.08±12.39)%/(18.09±7.38)%, AV(26.94±11.94)%/(25.52±8.64)%, AV+1(24.19±8.42)%/(20.82±8.69)%, AV+2(20.56±7.80)%/(15.60±9.71)%, total contribution(94.23±22.25)%, the disc wedging ratio/contribution ratio:AV-2D(2.88±2.57)%/(5.27±4.11)%, AV-1D(1.98±1.41)%/(2.29±2.16)%, AV+1D(-5.54±3.75)%/(-0.57±0.46)%, AV+2D(-8.27±4.62)%/(-1.22±1.11)%, total contribution (5.77±4.79)%. And the contribution rate of AV was significantly higher than that of adjacent vertebral(P<0.05).@*CONCLUSION@#The vertebral body and intervertebral disc shape both have influence on thoracolumbar kyphosis. However, the contribution of vertebral morphometry to the angle of TL/LDK deformity is relatively more important than the disc. The contribution of the wedge change of the AV to the TL/LDK deformity is particularly significant.

Sex Estimation of Typical Adult Vertebrae Morphology in Central China Based on CT Technique / 法医学杂志

Objective The morphological data of the second thoracic vertebra and the third lumbar vertebra were measured by computerized tomography （CT）. The sex differences were analyzed and the discrimination equation was obtained. Methods The data of 274 adults （203 cases from experimental group and 69 cases from validation group） from central China were collected. Four linear data （maximum transverse length of vertebral body, maximum longitudinal length of vertebral body, maximum transverse length of vertebral foramen, maximum longitudinal length of vertebral foramen）, one angle data （angle between spinous processes） and two area （vertebral foramen area, total cross-sectional area of vertebral body） data of the second thoracic vertebra and the third lumbar vertebra were collected, respectively. Then three ratios ［maximum transverse length/　maximum longitudinal length of vertebral body, maximum transverse length/ maximum longitudinal length of vertebral foramen, vertebral foramen area/ （total cross-sectional area of vertebral body-vertebral foramen area）］ and one angle （angle between spinous processes） were obtained. The discriminant equation was established for sexual discriminant analysis. Results The morphology of the second thoracic vertebra and the third lumbar vertebra was related with gender. Four single index discriminant formulae and eleven multi-index discriminant formulae were established. The 69 validation group samples were substituted into the formula for testing, and the maximum discriminant accuracy rate of the single-index discriminant formula was 75%. The maximum discriminant accuracy rate of multi-index discriminant formula was 83%. Conclusion It is feasible to conduct individual sex analysis by the morphological indexes of second thoracic vertebra and the third lumbar vertebra. The indexes have important application values in practice.

Síndrome de Klippel-Feil autosómico dominante: una malformación de segmentación vertebral / Klippel-Feil autosomal dominant syndrome: a malformation of vertebral segmentation

INTRODUCCIÓN: El síndrome de Klippel-Feil constituye un desorden esquelético complejo altamente heterogéneo caracterizado por la fusión congénita de dos o más vértebras cervicales. La triada clínica clásica consiste en cuello corto, implantación baja del cabello y limitación para los movimientos del cue llo. Las mutaciones asociadas se localizan en los loci del gen GDF3 (cromosoma 12p13.31), GDF6 (cromosoma 8q22.1) y MEOX1 (cromosoma 17q21.31). OBJETIVO: Describir los hallazgos clínico- radiológicos y genealogía de una paciente con síndrome de Klippel-Feil. CASO CLÍNICO: Paciente de 5 años de edad con cuello corto, cabello de implantación baja posterior, limitación para los movimientos de lateralización. La radiografía cervical en flexión y extensión evidenció bloques de fusión entre C1-2-3, C4-5 y C6-7. En la tomografía axial computarizada de tórax se apreció múltiples hemivértebras del tercio superior de las vértebras torácicas correspondientes a las costillas I-IV. El cariotipo fue normal, 46, XX. La penetrancia reducida estuvo presente en cinco de los miembros de la familia. La fusión de C2-3 predominó en cuatro y en un individuo la fusión baja en C5-6. Tres de los cinco individuos afectados tenían fusión entre el hueso grande y ganchoso. CONCLUSIÓN: La malformación de segmentación vertebral congénita constituye un caso de interés por tratarse de un diagnóstico infrecuente en la edad pediátrica y cuya sospecha puede generarse a partir del examen clínico, estudio de imágenes complementado con la interpretación de la genealogía en los trastornos de herencia mendeliana, permitiendo brindar un oportuno asesoramiento genético a la familia.

INTRODUCTION: Klippel-Feil syndrome is a highly heterogeneous complex skeletal disorder characterized by the con genital fusion of two or more cervical vertebrae. The classic clinical triad consists of a short neck, low hairline, and neck movements limitation. The associated mutations are located in the loci of the GDF3 gene (chromosome 12pl3.31), GDF6 (chromosome 8q22.1), and MEOXI (chromosome 17q21.31). OBJECTIVE: To describe the clinical-radiological findings and pedigree of a patient with Klippel-Feil syndrome. CLINICAL CASE: A 5-year-old patient with short neck, low posterior hairline, and limitation of lateral movements. The cervical flexion and extension radiographs showed fusion blocks between C1-2-3, C4-5, and C6-7. The chest CT scan showed multiple hemivertebrae in the upper third of the thoracic vertebrae corresponding to ribs 1-tv. The karyotype was normal, 46, XX. Reduced penetrance was present in five of the family members. The fusion of C2-3 was present in four members and one individual had low fusion in C5-6. Three of the five affected individuals had a fusion between the capitate and the hamate bone. CONCLUSION: The malformation of congenital vertebral segmentation is a case of interest since it is an uncommon diagnosis in the pediatric age and whose clinical suspicion can be generated from the clinical examination, radiological study com plemented with the pedigree interpretation in Mendelian inheritance disorders, allowing to provide opportunely genetic counseling to the family.

Hipoplasia vertebral asociada a cifosis toracolumbar en lactantes: ¿variante anatómica? casos clínicos / Lumbar hypoplasia associated to thoracolumbar kyphosis in infants: anatomic variant? clinical cases

INTRODUCCIÓN: La hipoplasia vertebral es una anomalía de los cuerpos vertebrales, en la que estos tienen forma de cuña, habitualmente a nivel de la unión toracolumbar. Si bien se asocia a ciertas enfermedades de depósito y displasias óseas, es posible encontrar una hipoplasia vertebral aislada en lactantes sanos, o en presencia de cifosis toracolumbar. El objetivo del presente manuscrito es dar a conocer la evolución de la hipoplasia vertebral asociada a cifosis en dos lactantes aparentemente sanos. CASOS CLÍNICOS: Se presentan dos casos de lactantes en que se pesquisó cifosis lumbar clínicamente visible durante la sedestación. Las radiografías de columna de ambos mostraron hipoplasia vertebral lumbar a nivel de L2 como único hallazgo en la morfología vertebral. Luego de descartar causas asociadas, se indicó manejo conservador: en el primer caso, en que la cifosis era de 18° se indicó seguimiento clínico-radiológico; mientras que, en el segundo caso, que tenía una angulación de 57° en sedestación, se indicó tratamiento con corsé. La evolución en ambos fue favorable, con re solución clínica radiológica a la edad de 15 meses en el primer caso y en el segundo caso, a los 3 años y 4 meses se constató regresión clínica de la cifosis con persistencia de una imagen de leve hipoplasia vertebral. CONCLUSIONES: La hipoplasia vertebral aislada o asociada a cifosis puede considerarse una anomalía menor o bien una variante anatómica del desarrollo de la columna del lactante, no obstan te, requiere seguimiento hasta su normalización.

INTRODUCTION: Vertebral hypoplasia is an anomaly of the vertebral bodies, in which they present a wedge shape, usually at the level of the thoracolumbar junction. Although it is associated with cer tain storage diseases and bone dysplasias, it is also possible to find isolated vertebral hypoplasia it in healthy infants or associated with thoracolumbar kyphosis. The objective of this report is to show the evolution of vertebral hypoplasia associated to kyphosis in two apparently health children. CASE REPORT: Two cases of infants diagnosed with clinically visible lumbar kyphosis when they were sitting. Spine X-rays of both showed lumbar vertebral hypoplasia at L2 level as the only finding. After ruling out other conditions associated with vertebral hypoplasia, conservative management was indicated; in the first case a clinical-radiological follow-up and in the second one, a corset given the magnitude of kyphosis. The evolution was favorable, with complete radiological clinical resolution at the age of 15 months in the first case and clinical regression in the second, in which, at 3 years and 4 months of age, an image of mild vertebral hypoplasia persisted. CONCLUSIONS: Isolated vertebral hypoplasia or associated to kyphosis may be considered a minor anomaly or anatomic variant of infant spine development, however, it requires follow-up until its normalization.

Assessment of the Original Height of L1~2 after Vertebral Compression Fracture / 法医学杂志

OBJECTIVES@#To explore the assessment method of original height of L1-2 after vertebral compression fracture and its application value in forensic clinical practice.@*METHODS@#A total of 154 normal thoracic and lumbar X-ray films were collected, and 140 cases were used as experimental group while 14 cases as validation group. The heights of anterior （Ha） and posterior （Hp） vertebral body of T₁₂-L₃ vertebrae in each X-ray image were measured. In the experimental group, the correlation analysis between HaL₁ and HaT₁₂, HpT₁₂, HpL₁, HaL₂ and HpL₂ was carried out, and regression equation was established via fitting. The correlation analysis between HaL₂ and HaL₁, HpL₁, HpL₂, HaL₃, HpL₃ was performed, and the regression equation was also established via fitting. The difference between the predicted and measured values of HaL₁ and HaL₂ in validation group was compared.@*RESULTS@#In the 140 normal subjects, HaL₁ （y₁） was well correlated with HaT₁₂ （x₁） and HaL₂（x₂）, and the multiple linear regression equation was y₁=2.545+0.423 x₁+0.486 x₂ （determining coefficient R²=0.712, P<0.05; F=169.206, P<0.05）. There was no significant difference between the predicted and actual measured values of HaL₁ in the validation group （ P>0.05）. HaL₂ （y₂） was well correlated with HaL₁ （x₃） and HaL₃ （x₄）, and the multiple linear regression equation was y₂=4.354+0.530 x₃+0.349 x₄ （determining coefficient R²=0.689, P<0.05; F=151.575, P<0.05）. There was no significant difference between the predicted and actual measured values of HaL₂ in the validation group （ P>0.05）.@*CONCLUSIONS@#It is more appropriate to evaluate the original height of L₁ or L₂ single vertebrae by comparing with the height of the anterior edge of the upper and lower adjacent vertebral bodies.

Clinical and radiographic outcomes of upper thoracic versus lower thoracic upper instrumented vertebrae for adult scoliosis: a meta-analysis

The aim of this study was to evaluate the clinical and radiographic outcomes of upper thoracic (UT) versus lower thoracic (LT) upper instrumented vertebrae (UIV) for adult scoliosis by meta-analysis. We conducted a literature search in three databases to retrieve related studies up to March 15, 2017. The preliminary screened studies were assessed by two reviewers according to the selection criteria. All analyses were carried out using the statistical software package R version 2.31. Odds ratios (OR) with 95% confidence intervals (CI) were used to describe the results. The I2 statistic and Q statistic test were used for heterogeneity assessment. Egger's test was performed to detect publication bias. To assess the effect of each study on the overall pooled OR or standardized mean difference (SMD), sensitive analysis was conducted. Ten trials published between 2007 and 2015 were eligible and included in our study. Meta-analysis revealed that the UT group was associated with more blood loss (SMD=0.4779, 95%CI=0.3349-0.6209, Z=6.55, P<0.0001) and longer operating time (SMD=0.5780, 95%CI=0.1971-0.958, Z=2.97, P=0.0029) than the LT group. However, there was no significant difference in Oswestry Disability Index, Scoliosis Research Society (SRS) function subscores, radiographic outcomes including sagittal vertical axis, lumbar lordosis, and thoracic kyphosis, length of hospital stay, and revision rates between the two groups. No evidence of publication bias was found between the two groups. Fusion from the lower thoracic spine (below T10) has as advantages a shorter operation time and less blood loss than upper thoracic spine (above T10) in posterior long-segment fixation for degenerative lumbar scoliosis.

Comparison of short-segment monoaxial and polyaxial pedicle screw fixation combined with intermediate screws in traumatic thoracolumbar fractures: a finite element study and clinical radiographic review

OBJECTIVES: No studies have compared monoaxial and polyaxial pedicle screws with regard to the von Mises stress of the instrumentation, intradiscal pressures of the adjacent segment and adjacent segment degeneration. METHODS: Short-segment monoaxial/polyaxial pedicle screw fixation techniques were compared using finite element methods, and the redistributed T11-L1 segment range of motion, largest maximal von Mises stress of the instrumentation, and intradiscal pressures of the adjacent segment under displacement loading were evaluated. Radiographic results of 230 patients with traumatic thoracolumbar fractures treated with these fixations were reviewed, and the sagittal Cobb's angle, vertebral body angle, anterior vertebral body height of the fractured vertebrae and adjacent segment degeneration were calculated and evaluated. RESULTS: The largest maximal values of the von Mises stress were 376.8 MPa for the pedicle screws in the short-segment monoaxial pedicle screw fixation model and 439.9 MPa for the rods in the intermediate monoaxial pedicle screw fixation model. The maximal intradiscal pressures of the upper adjacent segments were all greater than those of the lower adjacent segments. The maximal intradiscal pressures of the monoaxial pedicle screw fixation model were larger than those in the corresponding segments of the normal model. The radiographic results at the final follow-up evaluation showed that the mean loss of correction of the sagittal Cobb's angle, vertebral body angle and anterior vertebral body height were smallest in the intermediate monoaxial pedicle screw fixation group. Adjacent segment degeneration was less likely to be observed in the intermediate polyaxial pedicle screw fixation group but more likely to be observed in the intermediate monoaxial pedicle screw fixation group. CONCLUSION: Smaller von Mises stress in the pedicle screws and lower intradiscal pressure in the adjacent segment were observed in the polyaxial screw model than in the monoaxial pedicle screw fixation spine models. Fracture-level fixation could significantly correct kyphosis and reduce correction loss, and adjacent segment degeneration was less likely to be observed in the intermediate polyaxial pedicle screw fixation group.

Congenital hemangioma in spondylocostal dysostosis: a novel association

Abstract Congenital hemangioma is a benign tumor caused by dysfunction in embryogenesis and vasculogenesis, which progresses during fetal life to manifest as fully developed at birth. Although hemangiomas are the most common tumor of infancy, rapidly involuting congenital hemangioma has not been described in spondylocostal dysostosis. I report the novel association of congenital hemangioma and spondylocostal dysostosis in a Mexican newborn female patient with neural tube defects. Given the embryological relationship between skin and nervous system, I surmise that this association is not coincidental. I also propose that these morphologic alterations be incorporated to the spondylocostal dysostosis phenotype and specifically looked for in other affected children, in order to provide appropriate medical management and genetic counseling.

Percutaneous Vertebroplasty of the Entire Thoracic and Lumbar Vertebrae for Vertebral Compression Fractures Related to Chronic Glucocorticosteriod Use: Case Report and Review of Literature

Glucocorticosteroid-induced osteoporosis is the most frequent of all secondary types of osteoporosis, and can increase the risk of vertebral compression fractures (VCFs). There are promising additions to current medical treatment for appropriately selected osteoporotic patients. Few studies have reported on the efficiency of percutaneous vertebroplasty (PVP) or kyphoplasty for whole thoracic and lumbar glucocorticosteroid-induced osteoporotic vertebral compression fractures. We report a case of a 67-year-old man with intractable pain caused by successional VCFs treated by PVP.

A Case of Acute Lymphoblastic Leukemia Presenting with Protein-Losing Enteropathy / 대한소화기학회지

Protein-losing enteropathy (PLE) is a syndrome characterized by excessive gastrointestinal protein loss, resulting in hypoproteinemia and edema. A variety of benign and malignant conditions can be associated with PLE and acute leukemia is a very rare cause of PLE. We report a case of PLE associated with acute lymphoblastic leukemia. A 27-year-old man was admitted due to watery diarrhea, epigastric pain and bilateral leg edema. Laboratory findings showed hypoproteinemia and polycythemia. The diagnosis of PLE and acute lymphoblastic leukemia were confirmed on the measurement of fecal alpha1-antitrypsin clearance and bone marrow examination. After systemic chemotherapy and autologous stem cell transplantation, his clinical symptoms and abnormal laboratory findings were gradually improved.

Changes in Level of the Conus after Corrective Surgery for Scoliosis: MRI-Based Preliminary Study in 31 Patients

BACKGROUND: Detection of postoperative spinal cord level change can provide basic information about the spinal cord status, and electrophysiological studies regarding this point should be conducted in the future. METHODS: To determine the changes in the spinal cord level postoperatively and the possible associated factors, we prospectively studied 31 patients with scoliosis. All the patients underwent correction and posterior fusion using pedicle screws and rods between January 2008 and March 2009. The pre- and postoperative conus medullaris levels were determined by matching the axial magnetic resonance image to the sagittal scout image. The patients were divided according to the change in the postoperative conus medullaris level. The change group was defined as the patients who showed a change of more than one divided section in the vertebral column postoperatively, and the parameters of the change and non-change groups were compared. RESULTS: The mean pre- and postoperative Cobb's angle of the coronal curve was 76.80degrees +/- 17.19degrees and 33.23degrees +/- 14.39degrees, respectively. Eleven of 31 patients showed a lower conus medullaris level postoperatively. There were no differences in the pre- and postoperative magnitude of the coronal curve, lordosis and kyphosis between the groups. However, the postoperative degrees of correction of the coronal curve and lumbar lordosis were higher in the change group. There were also differences in the disease entities between the groups. A higher percentage of patients with Duchene muscular dystrophy had a change in level compared to that of the patients with cerebral palsy (83.3% vs. 45.5%, respectively). CONCLUSIONS: The conus medullaris level changed postoperatively in the patients with severe scoliosis. Overall, the postoperative degree of correction of the coronal curve was higher in the change group than that in the non-change group. The degrees of correction of the coronal curve and lumbar lordosis were related to the spinal cord level change after scoliosis correction.

The accuracy of pedicle screw placement in thoracic spine using the Funnel technique in idiopathic scoliosis.

STUDY DESIGN: A retrospective study of the accuracy of the pedicle screw placement in the thoracic spine using the Funnel technique in idiopathic scoliosis was conducted by using CT-scan analysis. OBJECTIVE: To evaluate the accuracy of thoracic pedicle screw placement using the Funnel technique in the surgical management of idiopathic scoliosis. BACKGROUND DATA: Placement of thoracic pedicle screw especially in idiopathic scoliosis is technically challenging. CT scan navigator is time-consuming and very expensive. Funnel technique was developed to locate the position of the pedicle and without using the CT guided navigator. There are no reports on the accuracy of pedicle screw instrumentation of the thoracic spine using the funnel technique in scoliosis surgery. MATERIAL AND METHOD: 117 screws in 14 patients with idiopathic scoliosis were investigated by computed tomography. Screw positioning was analyzed based on each spinal level, side of deformities (convex or concave side) and direction of cortical penetration. RESULT: Forty-one screws (35%) were placed within the pedicle. Forty-five screws (38%) breeched the medial cortex of pedicle and thirty-one screws (27%) breeched the lateral cortex of pedicle. The percentage of screws totally contained within the pedicle also varied by the thoracic regions: 43% was in between T1-T4, 29% was in between T5-T8, and 37% was in between T9-T12 level. However, there was no statistical difference between the spinal regions and the accuracy rate. Fifty-four screws were placed on the convex side of the spine and sixty-three screws were placed on the concave side. The percentage of totally contained within the pedicle in the convex and the concave side were 20% and 48% respectively. It had statistical difference (p = 0.004). Although medial perforation of the pedicle wall occurred in 38%, there were only 6.7% (3/45) of these that had canal encroachment of more than 4 mm. All of these occurred on the convex side. 62% and 31% of screws with medial perforation were less than 2 mm and 2.0-4.0 mm of canal intrusion respectively. Among the lateral penetration, 42% of these screws penetrated < 2 mm., 48% penetrated 2.0-4.0 mm., and 10% penetrated more than 4 mm. There was 3.4% (4/117 screws) that did not purchase the anterior portion of vertebral body. Although the percentage of totally contained screws was low, there was an 82.1% acceptable rate of screw position. These are screws that were fully contained within the pedicle plus medial perforation less than 2 mm (plus screws that had lateral penetration but purchased into the vertebral body). No screws perforated the anterior cortex of the vertebral body. There were no neurovascular complications. CONCLUSION: Placement of the thoracic pedicle screws using the Funnel technique in idiopathic scoliosis had an accuracy of 82. 1% (screws that were in acceptable position). There were no neurovascular related-complications by using this technique in the present study.

Early Results from Posterior Cervical Fusion with a Screw-Rod System

PURPOSE: We performed 65 cases of posterior fusion surgery for cervical and/or high thoracic lesions using a polyaxial screw-rod system. PATIENTS AND METHODS: A total of 486 screws were implanted in 65 patients. RESULTS: Fixation of the screws was carried out over an average of 2.9 spinal segments. Upon evaluation by postoperative CT scans, twelve (2.5%) screws had suboptimal trajectories but two of these revealed radiculopathy in one patient and required screw repositioning. No vascular sequelae resulted. There has been no segmental motion in any of the cases to date. As for other complications, there was one case of dural tearing and two cases of lateral mass fractures. There were no infections or other wound healing problems or hardware failures. No patients had neurological deterioration after surgery. There were statistically significant improvements in the mean Neck Disability Index (NDI) scores and Visual Analogue Scale (VAS) scores in the preoperative and late postoperative follow-up evaluations. Although further studies are required to establish the long-term results of fusion rates and clinical outcomes. CONCLUSION: We cautiously suggest that the posterior polyaxial screw-rod system can be safely used as a primary or additional fusion method in this risky region. The successful and safe use of this method is dependent on a precise preoperative surgical plan and tactics for ensuring safe screw fixation.

CT myelography of the thoraco-lumbar spine in 8 dogs with degenerative myelopathy

CT myelography of the T11-L2 region was performed in 8 large-breed dogs with a clinical diagnosis of degenerative myelopathy (DM) and 3 large-breed dogs that were clinically normal. CT myelographic characteristics were recorded for each dog, at each disc level. Area measurements of the spinal cord, dural sac, vertebral canal, and vertebral body were recorded at 4 slice locations for each disc level. Mean area ratios were calculated and graphically compared, by slice location and group. In all dogs, CT myelography identified morphologic abnormalities that were not suspected from conventional myelograms. Characteristics observed with higher frequency in DM versus normal dogs were: spinal stenosis, disc protrusion, focal attenuation of the subarachnoid space, spinal cord deformity, small spinal cord, and paraspinal muscle atrophy. Mean spinal cord: dural sac, spinal cord: vertebral canal, dural sac: vertebral canal, and vertebral canal:vertebral body ratios were smaller in DM versus normal dogs at more than one disc level. Some CT myelographic characteristics in DM dogs were similar to those previously reported in humans, dogs and horses with stenotic myelopathy.