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Author(s): Benjamin Lange

Abstract: Trauma patients with low clinical suspicion of cervical spine fracture are often examined with a plain X-ray cervical spine series rather than with cervical spine computed tomography (CT). The authors have been concerned by the absence of fractures in the group of patients examined with plain X-ray. The objective of this investigation was to determine the usefulness of plain X-ray examinations in suspected cases of cervical spine fracture compared to CT. A retrospective review was performed of all trauma patients undergoing imaging for suspected cervical spine fracture in our Emergency Department over a one-year period (January 1, 2007 to December 31, 2007). During the study period, 254 cervical spine plain X-ray and 3,080 cervical spine CT examinations were performed. Of the 254 plain X-ray examinations, 237 were interpreted as negative for fracture, 11 were suboptimal examinations, and six were interpreted as possible fractures (later ruled out by further imaging). Of the 3,080 CT examinations, 2,884 were interpreted as negative for fracture and 196 as positive. The overall positivity rates for acute cervical spine fracture were 0.0% in plain X-ray and 6.4% in CT examinations. These data confirm the authors’ concern that plain X-ray imaging for patients with low clinical suspicion for cervical spine trauma in our hospital may have too low a yield to justify its use. However, the 6.4% positivity rate in the group of patients selected for CT examination justifies its use in this group.

Author(s): Silvia Stacchiotti

Abstract: Background Chordoma is a rare tumor, and its natural history is still not well known.
Materials and Methods All patients affected by localized chordoma surgically treated at Istituto Ortopedico Rizzoli, Bologna, and Istituto Nazionale Tumori, Milan, Italy, between 1980 and 2008 were reviewed. Local recurrence, distant metastasis, and overall survival (OS) were analyzed both from time of diagnosis and from time of local recurrence/distant metastasis. A multivariable analysis to identify independent prognostic factors was carried out.
Results A total of 138 consecutive patients were identified (sacrum 78%, lumbar spine 15%, cervical-dorsal spine 7%). Of these, 130 underwent surgical resection. Median follow-up was 142 months. The 5- and 10-year OS, local relapse-free survival (LRFS), and distant relapse-free survival (DRFS) were, respectively, 78% and 54%, 52% and 33%, and 86% and 72%. Size was an independent prognostic factor for OS (P value < .001), LRFS (P value: .038), and DRFS (P value: .004), while surgical margins independently predicted LRFS (P value: .003) with a trend for OS. The 5- and 10-year OS, LRFS, and DRFS after the first local relapse were 50% and 26%, 47% and 31%, and 64% and 61%. The size of the recurrence and quality of surgical margins did not influence postrelapse OS. The 5-year OS after the second local relapse was 19%. 22% of patients developed distant metastases with a 5-year post-metastases OS of 33%.
Conclusions Tumor size and surgical margins affected outcome only on initial presentation. However, wide surgery was feasible in a minority of cases. Most patients died of local–regional disease even when metastases occurred. Indeed, long-term prognosis was such that disease-free survival at 10 years was only 26%.
Presented at 45th ASCO Annual Meeting, 2009, Orlando, FL, Abstract No. 10517.

Author(s): Sven Rainer Kantelhardt

Abstract: Background In contrast to other regions of the human spine, dorsal fixation with rods and pedicle screws is comparatively rarely performed in the cervical spine. Although this technique provides a higher mechanical strength than the more frequently used lateral mass screws, many surgeons fear the relatively high rate of misplacements. This higher incidence is mainly due to the complex vertebral anatomy in this spinal segment. For correct screw placement, the availability of an immediate and efficient intra-operative imaging tool to ascertain the accuracy of the pedicle screw hole position would be beneficial. We have previously investigated the usefulness of an intraspinal, specifically, intra-osseous ultrasound technique in the lumbar spine. In this study its accuracy as a means of controlling intrapedicular screw hole positioning has been evaluated in the cervical spine.
Methods An endovascular ultrasound transducer was used for the intra-luminal scanning of 54 pedicle screw holes in cadaveric human spine specimens. Twenty-three of these had been intentionally misplaced (cortex breached). The resulting image files were assessed by three investigators blinded to both the procedure and the corresponding CT findings.
Findings The investigators differentiated correctly between adequately and poorly placed pedicle screw holes in 96% of cases. False negatives and false positives both occurred in no more than 1.8% of cases.
Conclusions Intrapedicular ultrasonography of pedicle screw holes in the cervical spine is a promising technique for the intra-operative assessment of bore hole placement and may increase operative safety and postoperative outcome in posterior cervical fusion surgery.

Author(s): Dongil Choi

Abstract: Objective We evaluated the correlation of the absolute bone mineral density (BMD) values of the lumbar spine and standard sites of the proximal femur obtained from a Lunar Prodigy and the newly developed pencil-beam dual-energy X-ray absorptiometry (Dexxum).
Materials and methods Between June 2008 and December 2008, 79 Korean volunteers were enrolled. Measurements were obtained on the same day using both densitometers. The absolute BMD values (g/cm2) from the two densitometers were evaluated using Pearson’s correlation analysis with Bonferroni’s correction for the three clinically important sites. In order to evaluate precision, we performed duplicate Dexxum measurements, and calculated the within-subject coefficient of variation (WSCV).
Results The Pearson’s correlation coefficient (r) of BMD values for the total proximal femur, femoral neck, and lumbar spine by the two densitometers were 0.926, 0.948, and 0.955 respectively, and the null hypotheses of r = 0.8 were all rejected (p < 0.001 by one-sided Z-test with Fisher’s z-transformation for each site). The T-scores (r ≧ 0.842) and Z-scores (r ≧ 0.709) also showed strong positive correlations. The duplicate BMD values of Dexxum showed a high level of precision (WSCV ≦ 4.27%).
Conclusion Dexxum measurements of BMD, T-scores, and Z-scores showed a strong linear correlation with those measured on Lunar Prodigy.

Author(s): Giulio Zuccoli

Author(s): Marc Wybier

Abstract:

Author(s): Michele Lanotte

Abstract: We present a case of spinal cord compression in a 33-year-old male due to a T6–T7 paravertebral mass extending through the intervertebral foramen into the vertebral canal. Histopathological feature was consistent with an intra-vascular papillary endothelial hyperplasia. Differential diagnosis of the lesion and review of the literature are presented.

Author(s): Amer F Samdani

Abstract: The vertical expandable prosthetic titanium rib (VEPTR) was originally designed to treat chest and spine deformities in young children. However, older children with complex spinal deformities may also benefit from placement of a VEPTR when vertebral column resections are deemed too risky neurologically. We report: (1) the changes in Cobb angle, T1 angle, and head tilt; and (2) the occurrence of complications in children older than 10 years of age treated with VEPTR. From a database of 214 patients treated in a Food and Drug Administration Investigational Device Exemption study of VEPTR, we identified 10 patients with assorted diagnoses who underwent surgery after age 10 and had a minimum of 24-month followup (mean, 39.6 months; range, 24–75 months). No patient sustained neurologic injury. Patients underwent an average of five lengthenings. The mean preoperative Cobb angle was 64.7° and improved to 48.4°. Head shift improved an average of 3.8 cm. Two device-related complications occurred (both in the same patient). Four patients have since undergone definitive spinal fusion. For a select group of patients 10 years of age or older, the VEPTR offers a reasonable alternative to potentially risky vertebral column resections for correcting deformities in selected patients.
Level of Evidence: Level IV, therapeutic study. See Guidelines for Authors for a complete description of levels of evidence.
One or more of the authors (AFS, JBE, KS, RJC, RRB) have received funding from the Chest Wall and Spine Deformity Study Group, Synthes Spine, and AO Spine North America.
Each author certifies that his or her institution has approved the human protocol for this investigation, that all investigations were conducted in conformity with ethical principles of research, and that informed consent for participation in the study was obtained.
This work was performed at Shriners Hospital for Children, Philadelphia, PA.

Author(s): Arun Mullaji

Abstract: