Martin Kelbl

Genotypic versus phenotypic methods in the detection of Listeria monocytogenes prosthetic joint infection.

A rare case of a severe prosthetic joint infection in a 71-year-old immunocompetent woman is presented. Listeria monocytogenes was identified in two consecutive samples using broad-range PCR and sequencing, whereas cultivation remained negative for the first sample and streptococci of a non-group A streptococci, non-group B streptococci type were detected for the second one. This report demonstrates that the phenotypic approach may lead to misidentification of L. monocytogenes in a routine clinical setting. Molecular methods of pathogen detection might be useful when a rare and/or unexpected micro-organism is present or the sample is collected during antibiotic treatment.

Minimally invasive thoracoscopic approach to thoracolumbar junction fractures

AIMS A retrospective analysis of patients with thoracolumbar junction fractures who underwent video-assisted thoracoscopic surgery via a minimally invasive approach (minithoracotomy) for reconstruction of the anterior spinal column. METHODS Between 2002 and 2014, a total of 176 patients were treated by this technique. The patients received either posterior stabilization and, at the second stage, the minimally invasive technique via an anterior approach, or the minimally invasive anterior procedure alone. RESULTS In the anterior procedure, the average operative time was 90 min. (50 to 130 min). Bony fusion without complications was achieved in all patients within a year of surgery. The loss of correction after the anterior procedure with an allograft or titanium cage was up to 2 degrees at two years follow-up. CONCLUSION The minimally invasive approach (minithoracotomy up to 6-7 cm) combined with thoracoscopy is an alternative to an exclusively endoscopic technique enabling us to provide safe surgical treatment of the anterior spinal column.

Biomechanical Testing of Spinal Segment Fixed by Arcofix System on the Swine Spine

Study Design An in vitro biomechanical study. Purpose To evaluate the mechanical properties of the spinal segment in the intact, injured, and stabilized state after fixation by an Arcofix implant. Overview of Literature Several types of thoracolumbar spine injury necessitates anterior instrumentation. The Arcofix plate represents the latest generation of angular stablity systems. The biomechanical properties of these implants have not been sufficiently studied yet. Methods A total of ten porcine specimens (levels Th12-L3) were prepared. The tests were performed for intact, injured, and implanted specimens. In each state, the specimen was subjected to a tension load of a prescribed force, and subsequently, twisted by a given angle. The force load was 200 N. The torsion load had a deformation character, i.e., the control variable was the twisting angle and the measured variable was the moment of a couple. The amplitude of the load alternating cycle was 3°. Another parameter that was evaluated was the area of the hysteresis loop. The area corresponds to the deformation energy which is dissipated during the cycle. Results A statistically significant difference was found between the intact and injured states as well as between the injured and implanted specimens. The statistical evaluation also showed a statistically different value of the hysteresis loop area. In the case of instability, the area decreased to 33% of the physiological value. For the implanted sample, the area increased to 170% of the physiological value. Conclusions The Arcofix implant with its parameters appears to be suitable and sufficiently stable for the treatment of the anterior column of the spine.