[Proximal tibial fractures sustained during alpine skiing - incidence and risk factors]. / Proximale Tibiafrakturen im Skisport - Inzidenz und Risikofaktoren.

BACKGROUND: Prior to introduction of carving skis, complex fractures of the proximal tibia were rarely seen. Recently these fractures are being seen more frequently in connection with alpine skiing. The aim of this study was to find out the incidence of proximal tibia fractures in alpine skiing and to identify possible risk factors. METHODS: All patients with proximal tibia fractures related to alpine skiing in a large German ski resort were included. Fracture type, patient and skiing related factors were recorded. Incidence of fractures was determined by using the number of all registered skiers. Multinomial logistic regression analysis was used to calculate the odds ratios for risk factors. RESULTS: Between 2007 and 2010 a total of 188 patients was treated for proximal tibia fractures caused by alpine skiing. Forty-three patients had a type-A injury, 96 patients a type-B injury, and 49 patients a type-C injury. The incidence of injury increased continuously, starting from 2.7 and climbing to 7.0 per 105 skiing days. The risk factors compared to patients with type-A fractures, type-C fracture occurred in older (OR 0.93; 0.89 - 0.97) and heavier (OR 0.86; 0.74 - 0.99) individuals and were more likely on icy snow conditions (OR 0.22; 0.05 - 0.96), higher speed (OR 0.29; 0.09 - 0.97) and skiing skill (OR 0.35; 0.13 - 0.95). These was also seen in artificial and icy snow conditions (OR 0.25; 0.07 - 0.87) when compared to type-B fractures. CONCLUSION: The incidence of proximal tibia fractures related to skiing has increased over the past four years. Risk factors such as age, BMI, snow conditions, speed, and the skill of the skiers, were identified as causes contributing to complex fractures.

[Risk factors for failed cleansing following periprosthetic delayed hip prosthesis infection]. / Risikofaktoren für eine fehlgeschlagene Infektsanierung nach periprothetischer Hüftprothesenspätinfektion.

BACKGROUND: Despite extensive cleansing concepts recurrent infections are relatively common especially for infections of hip prostheses. The aim of this retrospective study was to identify factors which hinder cleansing and facilitate recurrence. MATERIALS AND METHODS: This study included 40 patients with periprosthetic delayed hip prosthesis infection who had been treated with the aim of infection cleansing between 2006 and 2008. Infection cleansing was carried out using a standardized treatment regimen with two and multiple phase reimplantation of the hip prosthesis following successful pathogen eradication. A clinical course follow-up was carried out after 2 years. RESULTS: Of the patients 18 (45%) were free of recurrence following successful eradication and reimplantation of the prosthesis and 5 (12.5%) suffered recurrence of infection after primarily successful revision prosthesis. In 17 patients (42.5%) treatment was switched to an alternative procedure primarily due to an uncleansable infection. In the group of patients with recurrent infections or untreatable infection, resistant pathogens could be detected significantly more often (p=0.001), in particular methicillin-resistant Staphylococcus aureus (MRSA), methicillin-resistant Staphylococcus epidermidis (MRSE) and highly resistant Pseudomonas. This group had a significantly worse American Society of Anesthesiologists (ASA) score (p = 0.002). The number of surgical interventions in this group was significantly higher. CONCLUSIONS: A poorer general physical condition and resistant infectious pathogens are the main risk factors for recurrent infections following prosthesis reimplantation. Therefore, a different treatment concept should be used for polymorbid patients with resistant pathogen infections.

[Reconstruction after spinal fractures in the thoracolumbar region]. / Rekonstruktion der ventralen Säule nach thorakolumbalen Wirbelsäulenverletzungen.

The morbidity of anterior approaches has significantly influenced the development of therapeutic concepts for the treatment of thoracolumbar spine fractures. Minimally-invasive techniques such as mini-open and endoscopic have enlarged the numbers of anterior reconstruction after spinal fractures in the thoracolumbar region. These minimally-invasive approaches have been facilitated by the development of special implants adapted to the new technique and to the local anatomical requirements.Two multi center studies in Germany (MCSI and II) showed the trend towards minimal invasive procedures and anterior approaches in the German speaking spine centers. Since the first report on thoracoscopic anterior procedures in Germany in 1997 a growing number of spine centers established this method. There is still no evidence based high level literature to substantiate a significant benefit for the patients by anatomical reduction and reconstruction of the anterior spinal column. However, there are some reports on better short outcomes in radiological parameters as well as better clinical results in 5 to 8 year follow-ups.The minimal invasive anterior approach seems to be advantageous for the patients by reducing significantly additive operation morbidity. It has become more important over the last two decades for anterior reconstruction after trauma and posttraumatic malalignment of the thoracolumbar spine.

O-arm(®)-based spinal navigation and intraoperative 3D-imaging: first experiences.

Since the first use of instrument-tracking techniques in the early 1990s, image-guided technologies became a leading topic in all branches of spine surgery. Today, navigation is a widely available tool in spine surgery and has become a part of clinical routine in many centers for a large variety of indications. Spinal navigation may not only contribute to more precision during surgery, but it may also reduce radiation exposure and fluoroscopy time, with advantages not only for the patient but also for the operating room personnel. Different registration algorithms have been developed differing in terms of the type of image data used by the navigation system (preoperatively acquired computed tomography [CT] images, intraoperatively acquired fluoroscopy images) and the way virtual and physical reality is matched. There is a tendency toward a higher accuracy for 3D fluoroscopy-based registration algorithms. The O-arm(®) represents a new flat-panel technology with the source and detector moving in a 360° arc around the patient. In combination with the Stealth(®) station system, navigation may start immediately after automated registration with already referenced instruments. After instrumentation, an additional scan may confirm intraoperatively the correct positioning of the instrumentation. The first experiences with the system are described in this paper.

Gas chromatographic determination and mechanism of formation of D-amino acids occurring in fermented and roasted cocoa beans, cocoa powder, chocolate and cocoa shell.

Fermented cocoa beans of various countries of origin (Ivory Coast, Ghana, Sulawesi), cocoa beans roasted under defined conditions (100-150 degrees C; 30-120 min), low and high fat cocoa powder, various brands of chocolate, and cocoa shells were analyzed for their contents of free L-and D-amino acids. Amino acids were isolated from defatted products using a cation exchanger and converted into volatile N(O)-pentafluoropropionyl amino acid 2-propyl esters which were analyzed by enantioselective gas chromatography mass spectrometry on a Chirasil-L-Val capillary column. Besides common protein L-amino acids low amounts of D-amino acids were detected in fermented cocoa beans. Quantities of D-amino acids increased on heating. On roasting cocoa beans of the Forastero type from the Ivory Coast at 150 degrees C for 2 h, relative quantities of D-amino acids approached 17.0% D-Ala, 11.7% D-Ile, 11.1% D-Asx (Asp + Asn), 7.9% D-Tyr, 5.8% D-Ser, 4.8% D-Leu, 4.3% D-Phe, 37.0% D-Pro, and 1.2% D-Val. In cocoa powder and chocolate relative quantities amounted to 14.5% D-Ala, 10.6% D-Tyr, 9.8% D-Phe, 8.1% L-Asx, and 7.2% D-Ile. Lower quantities of other D-amino acids were also detected. In order to corroborate our hypothesis that D-amino acids are generated from Amadori compounds (fructose amino acids) formed in the course of the Maillard reaction, fructose-L-phenylalanine and fructose-D-phenylalanine were synthesized and heated at 200 degrees C for 5-60 min. Already after 5 min release of 11.7% D-Phe and 11.8% L-Phe in the free form could be analyzed. Based on the data a racemization mechanism is presented founded on the intermediate and reversible formation of an amino acid carbanion in the Amadori compounds.