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1.

Background context

Three-dimensional (3D) deformations of the spine are predominantly characterized by two-dimensional (2D) angulation measurements in coronal and sagittal planes, using anteroposterior and lateral X-ray images. For coronal curves, a method originally described by Cobb and for sagittal curves a modified Cobb method are most widely used in practice, and these methods have been shown to exhibit good-to-excellent reliability and reproducibility, carried out either manually or by computer-based tools. Recently, an ultralow radiation dose–integrated radioimaging solution was introduced with special software for realistic 3D visualization and parametric characterization of the spinal column.

Purpose

Comparison of accuracy, correlation of measurement values, intraobserver and interrater reliability of methods by conventional manual 2D and sterEOS 3D measurements in a routine clinical setting.

Study design/setting

Retrospective nonrandomized study of diagnostic X-ray images created as part of a routine clinical protocol of eligible patients examined at our clinic during a 30-month period between July 2007 and December 2009.

Patient sample

In total, 201 individuals (170 females, 31 males; mean age, 19.88 years) including 10 healthy athletes with normal spine and patients with adolescent idiopathic scoliosis (175 cases), adult degenerative scoliosis (11 cases), and Scheuermann hyperkyphosis (5 cases). Overall range of coronal curves was between 2.4° and 117.5°. Analysis of accuracy and reliability of measurements were carried out on a group of all patients and in subgroups based on coronal plane deviation: 0° to 10° (Group 1, n=36), 10° to 25° (Group 2, n=25), 25° to 50° (Group 3, n=69), 50° to 75° (Group 4, n=49), and more than 75° (Group 5, n=22).

Methods

Coronal and sagittal curvature measurements were determined by three experienced examiners, using either traditional 2D methods or automatic measurements based on sterEOS 3D reconstructions. Manual measurements were performed three times, and sterEOS 3D reconstructions and automatic measurements were performed two times by each examiner. Means comparison t test, Pearson bivariate correlation analysis, reliability analysis by intraclass correlation coefficients for intraobserver reproducibility and interrater reliability were performed using SPSS v16.0 software (IBM Corp., Armonk, NY, USA). No funds were received in support of this work. No benefits in any form have been or will be received from a commercial party related directly or indirectly to the subject of this article.

Results

In comparison with manual 2D methods, only small and nonsignificant differences were detectable in sterEOS 3D–based curvature data. Intraobserver reliability was excellent for both methods, and interrater reproducibility was consistently higher for sterEOS 3D methods that was found to be unaffected by the magnitude of coronal curves or sagittal plane deviations.

Conclusions

This is the first clinical report on EOS 2D/3D system (EOS Imaging, Paris, France) and its sterEOS 3D software, documenting an excellent capability for accurate, reliable, and reproducible spinal curvature measurements.  相似文献   

2.

Background context

Adolescent idiopathic scoliosis (AIS) is a complex three-dimensional (3D) deformity of the spine involving deviations in the frontal plane, modifications of the sagittal profile, and rotations in the transverse plane. Although Lenke classification system is based on 2D radiographs and includes sagittal thoracic and coronal lumbar modifiers, Lenke et al. suggested inclusion of axial thoracic and lumbar modifiers in the analysis.

Purpose

To analyze axial plane of Lenke 1A curves to identify curve characteristics.

Study design

Retrospective study.

Patient sample

Seventy patients (49 women, 21 men) with Lenke Type 1A idiopathic scoliosis were analyzed.

Outcome measures

Coronal, sagittal, and axial parameters were measured from plain radiographs that were obtained at initial medical examination of the patients.

Methods

Coronal and sagittal plane and whole spine segmental vertebra rotations from thoracic 1 to lumbar 5 were evaluated in 70 AIS patients with Lenke 1A curves by using Drerup method. Three different subgroups were identified according to magnitude and direction of lower end vertebra (LEV) rotation.

Results

In Group 1 (Lenke 1A1), the direction of LEV rotation was same with other vertebrae in the main curve and the magnitude of the LEV rotation was less than −0.5°. In Group 2 (Lenke 1A2), the rotation of LEV was between −0.5° and 0.5° and so was accepted as neutral. In Group 3 (Lenke 1A3), the rotation of LEV had opposite direction with vertebrae in the main curve and the magnitude of LEV rotation was more than 0.5°. The mean thoracic Cobb angle of patients with Lenke 1A idiopathic scoliosis was 51.1° (range 37°–80°), whereas the mean lumbar Cobb angle was 16.4° (range 0°–32°). The mean angle of trunk rotation of the patients was 5.7° (range 1°–16°). In terms of maximum thoracic vertebra rotation, the mean rotation angle of Lenke 1A idiopathic curves was −18.9° (range −(9.8°–44.7°)). The mean maximum lumbar vertebra rotation was 4.5° (range −7.2° to 15.1°).

Conclusions

Addition of axial plane analysis to conventional coronal and sagittal evaluations in patients with Lenke 1A curves may reveal inherent structural differences that are not apparent in single planar radiographic assessments and may necessitate a different surgical strategy.  相似文献   

3.

Purpose

A new concept of vertebra vectors based on spinal three-dimensional (3D) reconstructions of images from the EOS system, a new low-dose X-ray imaging device, was recently proposed to facilitate interpretation of EOS 3D data, especially with regard to horizontal plane images. This retrospective study was aimed at the evaluation of the spinal layout visualized by EOS 3D and vertebra vectors before and after surgical correction, the comparison of scoliotic spine measurement values based on 3D vertebra vectors with measurements using conventional two-dimensional (2D) methods, and an evaluation of horizontal plane vector parameters for their relationship with the magnitude of scoliotic deformity.

Methods

95 patients with adolescent idiopathic scoliosis operated according to the Cotrel-Dubousset principle were subjected to EOS X-ray examinations pre- and postoperatively, followed by 3D reconstructions and generation of vertebra vectors in a calibrated coordinate system to calculate vector coordinates and parameters, as published earlier. Differences in values of conventional 2D Cobb methods and methods based on vertebra vectors were evaluated by means comparison T test and relationship of corresponding parameters was analysed by bivariate correlation. Relationship of horizontal plane vector parameters with the magnitude of scoliotic deformities and results of surgical correction were analysed by Pearson correlation and linear regression.

Results

In comparison to manual 2D methods, a very close relationship was detectable in vertebra vector-based curvature data for coronal curves (preop r 0.950, postop r 0.935) and thoracic kyphosis (preop r 0.893, postop r 0.896), while the found small difference in L1–L5 lordosis values (preop r 0.763, postop r 0.809) was shown to be strongly related to the magnitude of corresponding L5 wedge. The correlation analysis results revealed strong correlation between the magnitude of scoliosis and the lateral translation of apical vertebra in horizontal plane. The horizontal plane coordinates of the terminal and initial points of apical vertebra vectors represent this (r 0.701; r 0.667). Less strong correlation was detected in the axial rotation of apical vertebras and the magnitudes of the frontal curves (r 0.459).

Conclusions

Vertebra vectors provide a key opportunity to visualize spinal deformities in all three planes simultaneously. Measurement methods based on vertebral vectors proved to be just as accurate and reliable as conventional measurement methods for coronal and sagittal plane parameters. In addition, the horizontal plane display of the curves can be studied using the same vertebra vectors. Based on the vertebra vectors data, during the surgical treatment of spinal deformities, the diminution of the lateral translation of the vertebras seems to be more important in the results of the surgical correction than the correction of the axial rotation.  相似文献   

4.
Scoliosis is a multifactorial three-dimensional (3D) spinal deformity with integral and directly related vertebral deviations in the coronal, sagittal and horizontal planes. Current classification and diagnostic methods rely on two-dimensional (2D) frontal and lateral X-ray images; no routine methods are available for the visualization and quantitative evaluation of deviations in the horizontal plane. The EOS 2D/3D system presented here is a new, low-dose, orthopedic radiodiagnostic device based on Nobel prize-winning X-ray detection technology with special software for 3D surface reconstruction capabilities that finally led to a breakthrough in scoliosis diagnosis with high-quality, realistic 3D visualization and accurate quantitative parametric analysis. A new concept introducing vertebra vectors and vertebra vector parametric calculations is introduced that furnishes simplified visual and intelligible mathematical information facilitating interpretation of EOS 2D/3D data, especially with regard to the horizontal plane top view images. The concept is demonstrated by a reported scoliotic case that was readily characterized through information derived from vertebra vectors alone, supplemented with the current angulation measurement methods in the coronal and sagittal planes and axial vertebral rotation measurements in the horizontal plane, with a calibrated 3D coordinate system suitable for inter-individual comparisons. The new concept of vertebra vectors may serve as a basis for a truly 3D classification of scoliosis.  相似文献   

5.

Background context

Magnetically-controlled growing rod (MCGR) technology has been reported for the treatment of early-onset scoliosis (EOS). Such technology allows for regular and frequent outpatient rod distractions without the need for additional surgery. However, pre- and postdistraction spine radiographs are required to verify the amount of lengthening. This increased exposure to ionizing radiation in developing children significantly increases their risk profile for radiation-induced cancer and noncancerous morbidity.

Purpose

This study addressed the first and novel application and reliability of the use of ultrasonography, that has no ionizing radiation exposure, as an alternative to plain radiographs in the visualizing and confirming of rod distractions.

Study design

A prospective study.

Patient sample

Six EOS patients who underwent surgical treatment with MCGRs were prospectively recruited.

Outcome measures

Imaging measurements based on ultrasound and plain radiographs.

Methods

All patients were imaged via ultrasound, ease of rod identification was established, and the reliability and reproducibility of optimal reference point selection assessed blindly by three individuals. The clinical algorithm, using ultrasound, was subsequently implemented. Plain radiographs served as controls.

Results

Assessment of the rod's neck distance on ultrasound demonstrated a high degree of interrater reliability (a=0.99; p<.001). Intrarater reliability remained high on repeat measurements at different time intervals (a=1.00; p<.001). Satisfactory interrater reliability was noted when measuring the rod's neck (a=0.73; p=.010) and high reliability was noted in assessing the housing of the rod (a=0.85; p=.01) on plain radiographs. Under blinded conditions, 2 mm rod distraction measured on radiographs corresponded to 1.7 mm distraction on the ultrasound (standard deviation: 0.24 mm; p<.001). Subsequently, the clinical algorithm using ultrasound, instead of radiographs, has been successfully implemented.

Conclusions

This is the first study to report the use of a novel technique using noninvasive, nonionizing ultrasound to reliably document rod distractions in EOS patients. A high level of inter- and intrarater reliabilities were noted. More importantly, the use of ultrasonography may result in fewer whole spine radiographs from being taken in patients who have had MCGRs implanted for EOS; thereby decreasing their exposure to ionizing radiation and the potential risk of future radiation-induced diseases.  相似文献   

6.

Purpose

EOS 2D/3D is an integrated, low-dose orthopedic digital radioimaging solution, which, due to its groundbreaking properties, has recently shown an increasing application in scoliosis surgery. Its integrated sterEOS 3D software allows creation of patient-specific three-dimensional (3D) lower limb models, and can produce geometrical parameters in 3D. Currently there are a limited number of reports on EOS for lower limb applications.

Methods

Three-dimensional reconstructions of 256 hip and knee joints of 128 healthy subjects, as well as 53 hips and 46 knees of 69 patients with hip or knee arthritis, were evaluated based on orthogonal EOS two-dimensional (2D) images. Measurements for hips included femur and tibia length, total length of the extremity, femoral antetorsion and offset, femoral neck length, neck-shaft and hip-knee-shaft (HKS) angles. Lower limb alignment in both frontal and sagittal planes were determined in normal and arthritic knees. Values were compared with those obtained by standard methods published by others.

Results

Normal hip and knee geometrical parameters were found in our healthy subjects. In osteoarthritic cases, values for neck-shaft angle, femoral antetorsion, femur length and total length of the extremity were shown to decrease non-significantly. Evaluation of lower limb alignment in healthy and arthritic knees showed normal values in healthy subjects apart from three cases with an average six degrees varus. Arthritic knees were most frequently found to have a varus angulation, with the exception of 11 cases with normal or valgus alignment.

Conclusion

EOS 2D/3D with its sterEOS 3D reconstruction is useful for a comprehensive 3D examination of the lower limb. In the near future it may be suitable for daily routine diagnostics of orthopedic lower limb deformities as a primary examination method.  相似文献   

7.

Background context

Magnetic resonance imaging (MRI) is frequently used in the evaluation of degenerative conditions in the lumbar spine. The relative interrater and intrarater agreements of MRI findings across different pathologic conditions are underexplored, as most studies are focused on specific findings.

Purpose

The purpose of this study was to characterize the interrater and intrarater agreements of MRI findings used to assess the degenerative lumbar spine.

Study design

A retrospective diagnostic study at a large academic medical center was undertaken with a panel of orthopedic surgeons and musculoskeletal radiologists to assess lumbar MRIs using standardized criteria.

Patient sample

Seventy-five subjects who underwent routine lumbar spine MRI at our institution were included.

Outcome measures

Each MRI study was assessed for 10 lumbar degenerative findings using standardized criteria. Lumbar vertebral levels were assessed independently, where applicable, for a total of 52 data points collected per study.

Methods

T2-weighted axial and sagittal MRI sequences were presented in random order to the four reviewers (two orthopedic spine surgeons and two musculoskeletal radiologists) independently to determine interrater agreement. The first 10 studies were reevaluated at the end to determine intrarater agreement. Images were assessed using standardized and pilot-tested criteria to assess disc degeneration, stenosis, and other degenerative changes. Interrater and intrarater absolute percent agreements were calculated. To highlight the most clinically important MRI disagreements, a modified agreement analysis was also performed (in which disagreements between the lowest two severity grades for applicable conditions were ignored). Fleiss kappa coefficients for interrater agreement were determined.

Results

The overall absolute and modified interrater agreements were 76.9% and 93.5%, respectively. The absolute and modified intrarater agreements were 81.3% and 92.7%, respectively. Average Fleiss kappa coefficient was 0.431, suggesting moderate overall agreement. However, when stratified by condition, absolute interrater agreement ranged from 65.1% to 92.0%. Disc hydration, disc space height, and bone marrow changes exhibited the lowest absolute interrater agreements. The absolute intrarater agreement had a narrower range, from 74.5% to 91.5%. Fleiss kappa coefficients ranged from fair-to-substantial agreement (0.282–0.618).

Conclusions

Even in a study using standardized evaluation criteria, there was significant variability in the interrater and intrarater agreements of MRI in assessing different degenerative conditions of the lumbar spine. Clinicians should be aware of the condition-specific diagnostic limitations of MRI interpretation.  相似文献   

8.

Purpose

Corrective three dimensional (3D) effect of different braces is debatable. We evaluated differences in in-brace radiographic correction comparing a custom thoracic-lumbo-sacral-orthosis (TLSO) (T) brace to a Chêneau type TLSO (C) brace using 3D EOS reconstruction technology. Our primary research question was the 3D effect of brace on the spine and in particularly the apical vertebra rotation (AVR).

Methods

This was a retrospective comparative analysis of patients with adolescent idiopathic scoliosis who had orthogonal AP and lateral X-rays with and without brace. A 3D image of the spine was reconstructed. Coronal, sagittal and axial spine parameters were measured before bracing and then on the first post-brace X-ray. Brace efficacy in controlling coronal, sagittal and axial parameters was evaluated.

Results

Eighteen patients treated with the C brace and ten patients treated with the T brace were included. No difference was found regarding patients’ age, gender, magnitude of Cobb angle, sagittal parameters or AVR at inclusion. Following bracing, AVR was significantly reduced by the C brace compared to the T brace [average correction of 8.2° vs. 4.9° (P = 0.02)]. Coronal and sagittal correction did not differ significantly between the two groups.

Conclusions

By utilizing a novel 3D reconstruction technology, we were able to demonstrate that braces differ in their immediate effects on the spine. Although clinical relevance should be evaluated in a future trial we feel that the ability to measure treatment effects in 3D, and especially the transverse plane, is an important tool when evaluating different treatments.  相似文献   

9.

Background context

The X-STOP interspinous decompression device, as a treatment for neurogenic intermittent claudication (NIC) because of lumbar spinal stenosis (LSS), has been shown to be superior to nonoperative control treatment. Current Food and Drug Administration labeling limits X-STOP use to NIC patients with a maximum of 25° concomitant lumbar scoliosis. This value was arrived at arbitrarily by the device developers and is untested.

Purpose

To determine X-STOP utility for NIC in patients with concomitant lumbar scoliosis.

Study design

A prospective, single institution, clinical outcome study comparing patients with scoliosis with patients without scoliosis who underwent X-STOP interspinous decompression for NIC because of LSS.

Patient sample

A cohort of 179 consecutive patients, 63 with scoliosis (Cobb angle 11° or more) and 116 without scoliosis, with symptoms attributable to NIC treated between January 2006 and May 2007, were included in the study.

Outcome measures

All patients completed self-reported preoperative and minimum 1-year postoperative outcome forms. Functional measures included Oswestry Disability Index (ODI), visual analog scale (VAS) pain score, and maximum walking and standing times in minutes. Three questions measured patient satisfaction: How satisfied were you with the procedure (very satisfied, somewhat satisfied, somewhat dissatisfied, or very dissatisfied); Would you have the procedure again? (yes or no); Would you recommend the procedure to a friend? (yes or no).

Methods

Before analysis, the 179 consecutive X-STOP patients were divided into three groups: Group 1 (controls without scoliosis, n=116); Group 2 (low scoliosis: 11–25°, n=41), and Group 3 (high scoliosis: 26° or more, n=22). The three groups were not statistically different for any preoperative functional scores. Groups were analyzed for pre- to postoperative functional change and level of satisfaction. Segmental scoliosis at the treated level was also analyzed.

Results

Fifty-six percent of Group 1 and Group 2 patients, but only 18% of Group 3 patients, achieved the success criterion of an ODI improvement of 15 or more points (Group 3 the outlier, p=.004). The satisfaction rate was Group 1, 76%; Group 2, 78%; Group 3, 59% (Group 3 the outlier, p=.0001). On average, all three groups improved for each outcome: Group 1 (ODI 17.3, VAS 2.0, standing time 39 minutes, and walking time 43 minutes), Group 2 (ODI 20.0, VAS 1.9, standing time 65 minutes, and walking time 64 minutes), Group 3 (ODI 7.2, VAS 0.9, standing time 18 minutes, and walking time 16 minutes). There was no statistical relationship between any outcome and segmental scoliosis.

Conclusions

The outcome success rate for the X-STOP procedure to treat NIC is lower in patients with overall lumbar scoliosis more than 25° but is unaltered by segmental scoliosis at the affected level. Although patients and surgeons must be aware that the presence of more than 25° of scoliosis portends less favorable results with X-STOP implantation for NIC because of LSS, success in these patients is not precluded, and selection of treatment must be put into the context of individual patient risk and other treatment options.  相似文献   

10.

Background

CMAC videolaryngoscope has recently been introduced for videoscope guided intubation. The aim of our study was to compare and evaluate the efficacy of the conventional blade and the angulated D blade of the CMAC videolaryngoscope with the direct laryngoscopes in simulated cervical spine injury patients on the airway manikin.

Materials and methods

Following power analysis, 33 resident doctors were enrolled to perform endotracheal intubation using all the 4 different laryngoscopes namely the Macintosh laryngoscope, McCoy laryngoscope, conventional CMAC videolaryngoscope and the D blade of the CMAC videolaryngoscopes on the airway manikin in simulated cervical spine injury. The demographic variables of the resident doctors were recorded. The outcomes measured included vocal cord visualization (Cormack–Lehane grading), time taken to intubate, number of attempts for successful intubation and optimizing maneuvers required.

Results

The use of indirect videolaryngoscopes resulted in better glottic visualization in comparison to the direct laryngoscopes (CL‐I) in 20/33 (60.6%) in the Macintosh group, 24/33 (72.7%) in McCoy group, 30/33 in (90.9%) in Vlc group and 32/33 (96.9%) in Vld group. The time taken to intubate averaged to 15.54 ± 2.6 in Macintosh group, 18.90 ± 4.47 in McCoy group, 20.21 ± 7.9 in Vlc group and 27.42 ± 9.09 in Vld group. The 1st attempt intubation success rate was 84.8% (Macintosh), 72.7% (McCoy), 90.9% (Vlc) and, 78.7% (Vld).

Conclusions

The overall performance of the conventional CMAC blade proved to be the best when compared with the D‐blade CMAC, Macintosh blade and the McCoy blade for intubation in simulated cervical spine patients by anesthesia residents.  相似文献   

11.

Purpose

The global appearance of scoliosis in the horizontal plane is not really known. Therefore, the aims of this study were to analyze scoliosis in the horizontal plane using vertebral vectors in two patients classified with the same Lenke group, and to highlight the importance of the information obtained from these vertebral vector-based top-view images in clinical practice.

Methods

Two identical cases of scoliosis were selected, based on preoperative full-body standing anteroposterior and lateral radiographs obtained by the EOS? 2D/3D system. Three-dimensional (3D) surface reconstructions of the spinal curves were performed by using sterEOS? 3D software before and after surgery. In both patients, we also determined the vertebral vectors and horizontal plane coordinates for analyzing the curves mathematically before and after surgery.

Results

Despite the identical appearance of spinal curves in the frontal and sagittal planes, the horizontal views seemed to be significantly different. The vertebral vectors in the horizontal plane provided different types of parameters regarding scoliosis and the impact of surgical treatment: reducing lateral deviations, achieving harmony of the curves in the sagittal plane, and reducing rotations in the horizontal plane.

Conclusions

Vertebral vectors allow the evolution of scoliosis curve projections in the horizontal plane before and after surgical treatment, along with representation of the entire spine. The top view in the horizontal plane is essential to completely evaluate the scoliosis curves, because, despite the similar representations in the frontal and sagittal planes, the occurrence of scoliosis in the horizontal plane can be completely different.

Graphical abstract

These slides can be retrieved under Electronic Supplementary Material.
  相似文献   

12.

Study design

A retrospective analysis of 150 adolescents who underwent spinal fusion for idiopathic scoliosis.

Objective

To analyse the incidence of the postoperative proximal junctional kyphosis after posterior fusion to the upper thoracic vertebra in adolescents with idiopathic scoliosis and to explore its risk factors.

Summary of background data

The reported incidence of the proximal junctional kyphosis after the posterior fusion in patients with idiopathic scoliosis varies depending on surgical methods and strategies adopted by the institution.

Methods

The changes in the Cobb angle of the proximal junctional kyphosis on the lateral spine X-ray were measured and the presence of PJK was recorded. The risk factors were screened using statistical analysis.

Results

PJK occurred in 35 out of 123 patients with an overall incidence of 28%. Among them, 28 patients (80%) experienced PJK within 1.5 years after surgery. The PJK-inducing factors included greater than 10° intraoperative decrease in thoracic kyphosis, thoracoplasty, the use of a pedicle screw at the top vertebra, autogenous bone graft and fusion to the lower lumbar vertebra (below L2).

Conclusions

There is a high incidence of postoperative proximal junctional kyphosis after posterior fusion to the upper thoracic vertebra within 1.5 years after surgery in adolescents with idiopathic scoliosis. In order to reduce its incidence, the risk factors for PJK should be carefully evaluated before surgery.  相似文献   

13.

Background context

Cervical spondylolysis, which is defined as a cleft between the superior and inferior articular facets of the articular pillar, is a rare condition. The sixth cervical vertebra (C6) is the level most commonly affected. Cases involving C2, C3, C4, or C5 have also been reported. However, to date, no case of C7 spondylolysis has been reported.

Purpose

To present a rare case of bilateral spondylolysis of the seventh cervical vertebra (C7) in a 58-year-old man.

Study design

A case report.

Methods

A 58-year-old man visited our hospital with chronic posterior neck pain radiating to the left upper extremity. Magnetic resonance imaging (MRI) study revealed left foraminal disc herniations at C5–C6 and C6–C7. Cervical spondylolysis involving C7 was discovered incidentally during computed tomography (CT)–guided transforaminal steroid injection. Plain radiographs, CT images, and MRIs were reviewed thoroughly once again.

Results

The patient’s symptoms were relieved after he received CT-guided transforaminal steroid injections. Plain radiographs revealed a radiolucent defect in the articular pillar and cleft at the spinous process of C7. Computed tomography confirmed bilateral spondylolysis and spina bifida occulta of the C7 vertebra. Magnetic resonance imaging revealed absence of edema, which was suggestive of a chronic lesion.

Conclusion

Involvement of C7 is not exceptional in a case of cervical spondylolysis.  相似文献   

14.

Background context

Total disc arthroplasty is a motion-preserving spinal procedure that has been investigated for its impact on spinal motions and adjacent-level degeneration. However, the effects of disc arthroplasty on facet joint biomechanics remain undefined despite the critical role of these posterior elements on guiding and limiting spinal motion.

Purpose

The goal was to measure the pressure in the facet joint in cadaveric human cervical spines subjected to sagittal bending before and after implantation of the ProDisc-C (Synthes Spine Company, L.P, West Chester, PA, USA).

Study design

A biomechanical study was performed using cadaveric human cervical spines during sagittal bending in the intact and implanted conditions.

Methods

Seven C2–T1 osteoligamentous cadaveric cervical spines were instrumented with a transducer to measure the C5–C6 facet pressure profiles during physiological sagittal bending, before and after implantation of a ProDisc-C at that level. Rotations of the index segment and global cervical spine were also quantified.

Results

The mean C5–C6 range of motion significantly increased (p=.009) from 9.6°±5.1° in the intact condition to 16.2°±3.6° after implantation. However, despite such changes in rotation, there was no significant difference in the facet contact pressure during extension between the intact (64±30 kPa) and implanted (44±55 kPa) conditions. Similarly, there was no difference in facet pressure developed during flexion.

Conclusions

Although implantation of a ProDisc-C arthroplasty device at the C5–C6 level increases angular rotations, it does not significantly alter the local facet pressure at the index level in flexion or extension. Using a technique that preserves the capsular ligament, this study provides the first direct measurement of cervical facet pressure in a disc arthroplasty condition.  相似文献   

15.

Purpose

The classification of three-dimensional (3D) spinal deformities remains an open question in adolescent idiopathic scoliosis. Recent studies have investigated pattern classification based on explicit clinical parameters. An emerging trend however seeks to simplify complex spine geometries and capture the predominant modes of variability of the deformation. The objective of this study is to perform a 3D characterization and morphology analysis of the thoracic and thoraco/lumbar scoliotic spines (cross-sectional study). The presence of subgroups within all Lenke types will be investigated by analyzing a simplified representation of the geometric 3D reconstruction of a patient’s spine, and to establish the basis for a new classification approach based on a machine learning algorithm.

Methods

Three-dimensional reconstructions of coronal and sagittal standing radiographs of 663 patients, for a total of 915 visits, covering all types of deformities in adolescent idiopathic scoliosis (single, double and triple curves) and reviewed by the 3D Classification Committee of the Scoliosis Research Society, were analyzed using a machine learning algorithm based on stacked auto-encoders. The codes produced for each 3D reconstruction would be then grouped together using an unsupervised clustering method. For each identified cluster, Cobb angle and orientation of the plane of maximum curvature in the thoracic and lumbar curves, axial rotation of the apical vertebrae, kyphosis (T4–T12), lordosis (L1–S1) and pelvic incidence were obtained. No assumptions were made regarding grouping tendencies in the data nor were the number of clusters predefined.

Results

Eleven groups were revealed from the 915 visits, wherein the location of the main curve, kyphosis and lordosis were the three major discriminating factors with slight overlap between groups. Two main groups emerge among the eleven different clusters of patients: a first with small thoracic deformities and large lumbar deformities, while the other with large thoracic deformities and small lumbar curvature. The main factor that allowed identifying eleven distinct subgroups within the surgical patients (major curves) from Lenke type-1 to type-6 curves, was the location of the apical vertebra as identified by the planes of maximum curvature obtained in both thoracic and thoraco/lumbar segments. Both hypokyphotic and hyperkypothic clusters were primarily composed of Lenke 1–4 curve type patients, while a hyperlordotic cluster was composed of Lenke 5 and 6 curve type patients.

Conclusion

The stacked auto-encoder analysis technique helped to simplify the complex nature of 3D spine models, while preserving the intrinsic properties that are typically measured with explicit parameters derived from the 3D reconstruction.
  相似文献   

16.

Background context

There are rare reports of intraosseous ganglion cysts in the cervical spine. However, to our knowledge, there are no previous reports of these cysts occurring in the lumbar spine.

Purpose

To report a case of symptomatic lumbar spinal stenosis caused by an intraosseous ganglion cyst of the L4 lamina that communicated with the spinal canal.

Study design

Case report.

Methods

An 86-year-old woman was referred to our spine service for a 2-year history of anterior thigh and leg pain. Magnetic resonance imaging revealed a benign-appearing intraosseous cyst in the left L4 lamina communicating with a posterior epidural cyst at L4–L5 causing marked spinal stenosis. The patient was treated successfully with a laminectomy and resection.

Results

The patient underwent partial laminectomies of L4 and L5 preserving the interspinous ligaments between L5–S1 and L3–L4. The cyst was removed en bloc without violation of the cyst wall. Histopathologic examination revealed focal myxoid changes without a cellular lining of the cyst wall, confirming the diagnosis of intraosseous ganglion cyst.

Conclusions

This is the first report to describe an intraosseous ganglion cyst occurring in the lumbar spine. Although spinal stenosis is commonly a result of degenerative joint or disc disease, it occasionally may result from more obscure causes. This case illustrates a patient with an intraosseous ganglion cyst within the spinal lamina resulting in spinal stenosis, treated successfully with a laminectomy and resection.  相似文献   

17.

Background

Vitamin D has been reported as renoprotective agents in various studies. Recently, a few in vitro studies highlighted cross talk between vitamin D and peroxisome proliferator–activated receptor gamma (PPAR-γ). The present study investigated the activation of PPAR-γ as novel mechanism in vitamin D–mediated protection against ischemia reperfusion–induced acute kidney injury (AKI) in rats.

Materials and methods

The AKI was induced by clamping renal pedicles for 40 min followed by reperfusion for 24 h. The AKI was assessed by measuring creatinine clearance, serum urea, uric acid level, and lactate dehydrogenase activity. Moreover, serum potassium, calcium level, fractional excretion of sodium, and microproteinuria were measured in rats. The oxidative stress in renal tissues was assessed by quantification of thiobarbituric acid–reactive substances, superoxide anion generation, reduced glutathione level, and catalase and myeloperoxidase activities. The hematoxylin-eosin staining was carried out to observe histopathologic changes in renal tissues. Vitamin D (0.25, 0.5, and 1 μg/kg) was administered for 7 d before subjecting rats to renal ischemia reperfusion injury (IRI).

Results

The renal IRI in rats induced significant changes in serum, urinary, and oxidative stress parameters in renal tissues. Moreover, hematoxylin-eosin staining revealed marked damage produced by IRI in renal tissues. The administration of vitamin D at 0.5 μg/kg dose afforded maximum protection against renal IRI. The prior treatment with PPAR-γ antagonist bisphenol A diglycidyl ether significantly attenuated protective effect of vitamin D, thus confirming involvement of PPAR-γ in vitamin D–mediated renoprotection.

Conclusions

It is concluded that activation of PPAR-γ significantly contributes toward vitamin D–mediated protection against ischemia reperfusion–induced AKI.  相似文献   

18.

Background

A precise comparison of supine and standing whole spine alignment in both the coronal and sagittal planes, including the pelvic parameters, has not been reported. Furthermore, previous studies investigated positional differences in the Cobb angle only in young patients with idiopathic scoliosis. The difference in alignment has never been investigated in a population of patients with adult spinal deformity (ASD). In most cases, ASD patients are aware of the symptoms when standing and tend to stoop with back pain, whereas the symptoms disappear when lying on a bed. Therefore, it is important to elucidate the positional differences in the deformity in older adults. The purposes of this study are to establish a method for comparing whole spine alignment between supine and standing, and to clarify the positional difference of the alignment in the patients with ASD.

Methods

Twenty-four patients with ASD (mean age: 60.1?years, range 20–80?years; 24 women) were evaluated. A slot-scanning three-dimensional X-ray imager (EOS) was used to assess the whole spine in the standing position. Computed tomography was used to assess the whole spine in the supine position. The computed tomography DICOM dataset of the whole spine in the supine position was transformed to two-dimensional (coronal and sagittal) digital reconstructed radiography images. The digital reconstructed radiography images were input for three-dimensional measurement by the EOS software and compared with the standing whole spine alignment measured by EOS.

Results

The mean intraclass correlation coefficients (supine, standing) of intra-rater / inter-rater reliabilities for the measured parameters were 0.981, 0.984 / 0.970, 0.986, respectively. The Cobb and rotation angles of the major curve, mostly the thoracolumbar area, were significantly greater in the standing position than in the supine position. Lumbar lordosis during standing was significantly kyphotic. With respect to the pelvic parameters, the sacral slope was significantly smaller in the standing position than in the supine position. Pelvic tilt and pelvic incidence were significantly greater in the standing position than in the supine position.

Conclusions

The lumbar to pelvic parameters and the major curve in standing position significantly deteriorate compared with the supine position in patients with ASD.
  相似文献   

19.

Background

High-grade acromioclavicular (AC) joint separations require surgical treatment, as conservative treatment may result in functional decline or persistent pain. Although many surgical techniques have been described in the literature, there is still no non-controversial gold standard procedure for AC joint dislocation. The different orientation of the two components of the coracoclavicular (CC) ligaments has been proven to account for different functions. However, the majority of the techniques reconstruct the CC ligaments with a single structure. The purposes of this study were to assess the feasibility of truly anatomic coracoclavicular ligament reconstruction (TACCR) and to determine the corresponding drilling parameter.

Methods

We constructed virtual three-dimensional (3D) models of 105 shoulders from computed tomography (CT) scan data by using SuperImage software. For each model, the attachment sites and footprint dimensions of the conoid and trapezoid ligaments were defined and adjusted according to previously defined anatomic parameters and individual measurement results. Virtual drilling and 3D measurement were carried out in each model separately. Guided by the drilling parameter, we performed TACCR on 24 shoulders from 12 whole cadavers after transecting the AC and CC ligaments.

Results

The collinear drilling technique was noted to breach the bone cortex of the clavicle and/or the coracoid process in 95 of 105 virtual models (90.5%). No cortical breach was observed using a non-collinear drilling technique. The anteversion angulation of the conoid–coracoid tunnel ranged from 10° to 15° (mean value 12.4°). The extraversion angulation of the conoid–coracoid tunnel varied from 5° to 10° (mean value 6.8°). The anteversion angulation of the trapezoid–coracoid tunnel ranged from 20° to 30° (mean value 25.2°). There were no failures when performing the non-collinear drilling technique on cadaver models.

Conclusions

The collinear drilling technique is not technically feasible for TACCR. For this reason, we recommend the non-collinear drilling technique, which provides the ability to prepare bony tunnels without any risk of cortical breach.

Clinical relevance

Based on this computer and cadaver model study, we have devised a novel drilling technique to restore the CC ligaments anatomically.  相似文献   

20.

Study design

Radiological reproducibility study.

Purpose

To assess intra and interobserver reliability of radiographic measurements for global sagittal balance parameters and sagittal spine curves, including cervical spine.

Summary of background data

Sagittal spine balance in adolescent idiopathic scoliosis (AIS) is a main issue and many studies have been reported, showing that coronal and sagittal deformities often involve sagittal cervical unbalance. Global sagittal balance aims to obtain a horizontal gaze and gravity line at top of hips when subject is in a static position, involving adjustment of each spine curvature in the sagittal plane. To our knowledge, no study did use a methodologically validated imaging analysis tool able to appreciate sagittal spine contours and distances in AIS and especially in the cervical region.

Methods

Lateral full-spine low-dose EOS radiographs were performed in 75 patients divided in three groups (control subjects, AIS, operated AIS). Three observers digitally analyzed twice each radiograph and 11 sagittal measures were collected for each image. Reliability was assessed calculating intraobserver Pearson’s r correlation coefficient, interobserver intra-class correlation coefficient (ICC) completed with a two-by-two Bland–Altman plot analysis.

Results

This measurement method has shown excellent intra and interobserver reliability in all parameters, sagittal curvatures, pelvic parameters and global sagittal balance.

Conclusions

This study validated a simple and efficient tool in AIS sagittal contour analysis. It defined new relevant landmarks allowing to characterize cervical segmental curvatures and cervical involvement in global balance.  相似文献   

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