The cement prosthesis-like spacer: an intermediate halt on the road to healing.

BACKGROUND Periprosthetic infections remain a devastating problem in the field of joint arthroplasty. In the following study, the results of a two-stage treatment protocol for chronic periprosthetic infections using an intraoperatively molded cement prosthesis-like spacer (CPLS) are presented. METHODS Seventy-five patients with chronically infected knee prosthesis received a two-stage revision procedure with the newly developed CPLS between June 2006 and June 2011. Based on the microorganism involved, patients were grouped into either easy to treat (ETT) or difficult to treat (DTT) and treated accordingly. Range of motion (ROM) and the knee society score (KSS) were utilized for functional assessment. RESULTS Mean duration of the CPLS implant in the DTT group was 3.6 months (range 3-5 months) and in the ETT group 1.3 months (range 0.7-2.5 months). Reinfection rates of the final prosthesis were 9.6% in the ETT and 8.3% in the DTT group with no significant difference between both groups regarding ROM or KSS (P = 0.87, 0.64, resp.). CONCLUSION The results show that ETT patients do not necessitate the same treatment protocol as DTT patients to achieve the same goal, emphasizing the need to differentiate between therapeutic regimes. We also highlight the feasibility of CLPS in two-stage protocols.

In vitro temperature evaluation during cement augmentation of proximal humerus plate screw tips

BACKGROUND The treatment of proximal humerus fractures in patients with poor bone quality remains a challenge in trauma surgery. Augmentation with polymethylmethacrylate (PMMA) cement is a possible method to strengthen the implant anchorage in osteoporotic bone and to avoid loss of reduction and reduce the cut-out risk. The polymerisation of PMMA during cement setting leads, however, to an exothermic reaction and the development of supraphysiological temperatures may harm the bone and cartilage. This study addresses the issue of heat development during augmentation of subchondrally placed proximal humerus plate screws with PMMA and the possible risk of bone and cartilage necrosis and apoptosis. METHODS Seven fresh frozen humeri from geriatric female donors were instrumented with the proximal humerus interlocking system (PHILOS) plate and placed in a 37°C water bath. Thereafter, four proximal perforated screws were augmented with 0.5 ml PMMA each. During augmentation, the temperatures in the subchondral bone and on the articular surface were recorded with K-type thermocouples. The measured temperatures were compared to threshold values for necrosis and apoptosis of bone and cartilage reported in the literature. RESULTS The heat development was highest around the augmented tips of the perforated screws and diminished with growing distance from the cement cloud. The highest temperature recorded in the subchondral bone reached 43.5°C and the longest exposure time above 42°C was 86s. The highest temperature measured on the articular surface amounted to 38.6°C and the longest exposure time above 38°C was 5 min and 32s. CONCLUSION The study shows that augmentation of the proximal screws of the PHILOS plate with PMMA leads to a locally limited development of supraphysiological temperatures in the cement cloud and closely around it. The critical threshold values for necrosis and apoptosis of cartilage and subchondral bone reported in the literature, however, are not reached. In order to avoid cement extravasation, special care should be taken in detecting perforations or intra-articular cracks in the humeral head.

Reliabilität von retrospektiven Berufsverlaufsdaten. Ein Vergleich zwischen dem öffentlichen Dienst und der Privatwirtschaft anhand von Panel-Daten

Im vorliegenden Beitrag wird die Zuverlässigkeit retrospektiver Angaben der Befragten zu beruflichen Tätigkeiten in ihrem Berufsverlauf untersucht. Insbesondere ist ausgehend von einem Befund von De Graaf und Wegener (1989) zu klären, ob generell Beschäftigte des öffentlichen Dienstes ihren Berufsverlauf unzuverlässiger erinnern als Staatsbeschäftigte. Es wird davon ausgegangen, dass gerade Beamte aufgrund der institutionellen Besonderheiten ihrer Beschäftigung größere Schwierigkeiten haben, ihren Berufsverlauf konsistent zu rekonstruieren als andere Befragte. Empirische Analysen von Panel-Daten erhärten diese Vermutung, was die Anzahl der beruflichen Tätigkeiten anbelangt. Jedoch machen Beamte zu anderen Attributen ihres Berufsverlaufs ebenso zuverlässige Angaben wie andere Befragte auch. Diese beamtenspezifischen Erinnerungsprobleme sind bei zukünftigen Erhebungen mittels ereignisorientierter Befragungsinstrumente zu berücksichtigen.

Critical incidence reporting systems - an option in equine anaesthesia? Results from a panel meeting.

OBJECTIVE To provide a brief introduction into Critical Incident Reporting Systems (CIRS) as used in human medicine, and to report the discussion from a recent panel meeting discussion with 23 equine anaesthetists in preparation for a new CEPEF-4 (Confidential Enquiry into Perioperative Equine Fatalities) study. STUDY DESIGN Moderated group discussions, and review of literature. METHODS The first group discussion focused on the definition of 'preventable critical incidents' and/or 'near misses' in the context of equine anaesthesia. The second group discussion focused on categorizing critical incidents according to an established framework for analysing risk and safety in clinical medicine. RESULTS While critical incidents do occur in equine anaesthesia, no critical incident reporting system including systematic collection and analysis of critical incidents is in place. CONCLUSIONS AND CLINICAL RELEVANCE Critical incident reporting systems could be used to improve safety in equine anaesthesia - in addition to other study types such as mortality studies.

Privacy Panel: Usable and Quantifiable Mobile Privacy

The ever increasing popularity of apps stems from their ability to provide highly customized services to the user. The flip side is that in order to provide such services, apps need access to very sensitive private information about the user. This leads to malicious apps that collect personal user information in the background and exploit it in various ways. Studies have shown that current app vetting processes which are mainly restricted to install time verification mechanisms are incapable of detecting and preventing such attacks. We argue that the missing fundamental aspect here is a comprehensive and usable mobile privacy solution, one that not only protects the user's location information, but also other equally sensitive user data such as the user's contacts and documents. A solution that is usable by the average user who does not understand or care about the low level technical details. To bridge this gap, we propose privacy metrics that quantify low-level app accesses in terms of privacy impact and transforms them to high-level user understandable ratings. We also provide the design and architecture of our Privacy Panel app that represents the computed ratings in a graphical user-friendly format and allows the user to define policies based on them. Finally, experimental results are given to validate the scalability of the proposed solution.

Panel report ECIS 2012: publication strategy for junior researchers: quantity vs. quality, importance of the first authorship and collaboration

The publication record is a key component of a successful academic career in IS. Despite its importance, its definition - especially for junior researchers―remains unclear. Is it better to have one A-publication or three Bpublications? Does being the third author on an A-publication carry more weight than being the first author on a Bpublication? Is it better to publish with as few co-authors as possible to demonstrate ability for independent work or is publishing with others a sign of good teamwork and academic excellence? Faced with these uncertainties, young researchers increasingly question the choices they make regarding their publication strategy. If unaddressed, these issues are bound to interfere with the quality of the IS research and scholars’ job satisfaction. This article raises these concerns associated with a publication strategy for junior researchers and reports the views voiced by five academics at a panel session at the European Conference on Information Systems 2012. In particular, the following topics are discussed: quantity vs. quality, value of the first authorship, the “optimal” number of authors, and the issues of co-authorship with an academic supervisor.