Biomedical subjects

Christopher S Bailey

Publications and source records attributed to Christopher S Bailey.

5 recordsLinked to original sources

PubMed2006

Comparison of operative and nonoperative treatment for thoracolumbar burst fractures in patients without neurological deficit: a systematic review.

OBJECT: Despite extensive published research on thoracolumbar burst fractures, controversy still surrounds which is the most appropriate treatment. The objective of this study was to evaluate the scientific literature on operative and nonoperative treatment of patients with thoracolumbar burst fractures and no neurological deficit. METHODS: In their search of the literature, the authors identified all possible relevant studies concerning thoracolumbar burst fracture without neurological deficit. Two independent observers performed study selection, methodological quality assessment, and data extraction in a blinded and objective manner for all papers identified during the search. In a synthesis of the literature, the authors obtained evidence for both operative and nonoperative treatments. CONCLUSIONS: There is a lack of evidence demonstrating the superiority of one approach over the other as measured using generic and disease-specific health-related quality of life scales. There is no scientific evidence linking posttraumatic kyphosis to clinical outcomes. The authors found that there is a strong need for improved clinical research methodology to be applied to this patient population.

Back Pain↗

PubMed2006

En bloc marginal excision of a multilevel cervical chordoma. Case report.

The purpose of this case report is to demonstrate that an en bloc resection with negative surgical margins can be successfully achieved in a case of a seemingly unresectable C-2 chordoma if appropriate preoperative staging and planning are performed. The management of chordomas is controversial and challenging because of their location and often large size at presentation. Because chordomas are malignant and will aggressively recur locally if intralesional resection is conducted, wide or true en bloc resection is generally recommended. The literature indicates, however, that surgeons are reluctant to perform wide or even marginal resections because of the lesion's complex surrounding anatomy and the risk of significant neurological compromise when a tumor abuts the dura mater or neural tissues. In this report the authors outline the successful en bloc resection of a large C1-3 chordoma and discuss the importance of preoperative staging and planning.

Biopsy, Needle↗

PubMed2005

Interbody device shape and size are important to strengthen the vertebra-implant interface.

STUDY DESIGN: An in vitro cadaveric study to compare compressive failure load, strength, and stiffness of the implant-vertebra interface. OBJECTIVES: To determine the effect of cage shape (kidney, cloverleaf, or oval) and cage surface area on endplate failure strength and secondly to determine the extent and pattern of trabecular failure adjacent to an interbody device. SUMMARY OF BACKGROUND DATA: Recent studies indicate that the posterolateral and peripheral regions of the endplate are stronger than the central. Current implants are not designed to take advantage of these stronger regions of the endplate. The zone of trabecular failure that results from interbody device subsidence has not been reported extensively in the literature. METHODS: Uniaxial compression testing with unrestricted rotation was carried out on the superior endplates of 48 thoracolumbar (T9-L2) vertebrae with 1 of 3 shaped indentors covering 20% or 40% of the endplate area. Failure load, failure strength, and stiffness were compared. Quantitative computed tomography scans were carried out before and following indentation tests to identify areas of trabecular densification that indicate localized failure. RESULTS: The cloverleaf-shaped indentors resulted in significantly higher (P < 0.001) failure loads (by >45%), strength (>49%), and construct stiffness (>35%) for both the 20% and 40% cross-sectional area sizes. Trabecular bone failure occurred in a semielliptical zone underlying the interbody devices, leaving the endplate and underlying cancellous bone intact. CONCLUSIONS: The cloverleaf-shaped indentor displayed an improved strength and stiffness profile when compared to oval or kidney-shaped indentors of similar surface areas.

Aged↗

PubMed2004

Type II error in the spine surgical literature.

STUDY DESIGN: A literature review. OBJECTIVES: To determine the frequency of potential type II errors published in the spine surgical literature. SUMMARY OF BACKGROUND DATA: The randomized controlled trial is the strongest clinical evidence available in investigational medicine. Unfortunately, it is common for randomized controlled trials published in peer-reviewed journals not to report a primary question or a sample size calculation. When the null hypothesis is accepted and the power of a study is unreported, the validity of a study's findings may be significantly limited. To our knowledge, the spine literature has not been appraised to determine the frequency of type II errors. METHODS.: A literature search was conducted of MED-LINE, PubMed, and Cochrane databases, using the key words of "spine" and "surgery" between 1967 and 2002. Trials were included if they were of a 2-group randomized controlled trial design, which reported a nonsignificant difference in the primary outcome. The frequency of reporting the primary outcome and sample size calculation was determined. The sample size was assessed to determine whether the trial had sufficient patients to detect a 10%, 25%, and 35% relative difference in the primary outcome for a power of 80%. RESULTS: A total of 37 studies satisfied the inclusion criteria. Six studies reported a sample size calculation (17%). Of the remaining 31 studies, 5 explicitly stated a primary outcome (14%). The mean type II error (beta error) was 82%. CONCLUSION: The spine surgical literature is plagued with a high potential for type II error. A trial's methodology should be scrutinized to prevent misinterpretation of the results.

Bibliometrics↗

PubMed2002

Posterior ankle arthroscopy: an anatomic study.

BACKGROUND: Ankle arthroscopy has generally been performed with use of anterior portals with the patient in the supine position. Little has been published on ankle arthroscopy performed with use of posterior portals, particularly with the patient in the prone position. The purpose of the present study was to evaluate the relative safety and efficacy of ankle arthroscopy with use of posterior portals with the limb in the prone position. METHODS: Thirteen fresh-frozen cadaver specimens were used. Posterolateral and posteromedial portals were established. Arthroscopy was performed, and the extent of the talar dome that could be visualized was marked. Four-millimeter plastic cannulae were filled with oil and were placed in the portals for use as reference landmarks on magnetic resonance imaging studies. The proximity of the portal cannulae to the adjacent structures was measured on standard magnetic resonance images and then during careful dissection. The distances measured by dissection were compared with the measurements made on magnetic resonance images. RESULTS: An average of 54% (range, 42% to 73%) of the talar dome could be visualized. The average distance between a cannula and adjacent anatomic structures after dissection was 3.2 mm (range, 0 to 8.9 mm) to the sural nerve, 4.8 mm (range, 0 to 11.0 mm) to the small saphenous vein, 6.4 mm (range, 0 to 16.2 mm) to the tibial nerve, 9.6 mm (range, 2.4 to 20.1 mm) to the posterior tibial artery, 17 mm (range, 19 to 31 mm) to the medial calcaneal nerve, and 2.7 mm (range, 0 to 11.2 mm) to the flexor hallucis longus tendon. The magnetic resonance images demonstrated very similar distances except in the case of the distance between the posteromedial cannula and the tibial nerve, which often was difficult to specifically identify on magnetic resonance imaging studies. CONCLUSIONS: The findings of the present cadaveric study suggest that, with the patient in the prone position, arthroscopic equipment may be introduced into the posterior aspect of the ankle without gross injury to the posterior neurovascular structures. Limited clinical trials should be carried out to confirm this finding.

Ankle Injuries↗