Die Knietotalendoprothese

For total knee arthroplasty following osteoarthritis the appropriate prosthesis design, fixation method and degree of constraint have to be decided preoperatively. In general three types of constraint are distinguished: unconstrained, semi-constrained and linked-constrained. In knees with no complex deformity or need for difficult ligament balancing an unconstrained design can be chosen. Cruciate-retaining and cruciate-substituting prostheses are both associated with certain advantages and disadvantages but according to the current literature neither technique is superior. Mobile bearings are hypothesized to reduce wear and forces applied across the knee but no clear clinical benefit has been observed. If adequate stability in the coronal plane cannot be achieved a semi-constrained prosthesis with stem fixation should be used. Among (semi-) constrained designs prostheses with a rotating platform show significantly better results with regard to aseptic loosening and revision rates. Routine resurfacing of the patella seems to be beneficial when using posterior stabilized prostheses. Most studies show superior results for cemented or hybrid fixation compared to cementless prostheses.     

Konservative Therapie der chronischen Enthesiopathien

The majority of insertional and noninsertional tendinopathy cases are associated with repetitive or overuse injuries. Certain tendons are particularly vulnerable to degenerative pathology; these include the Achilles and patella tendon, the rotator cuff, and forearm extensors/flexors. Disorders of these tendons are often chronic and can be difficult to manage successfully in the long term. Eccentric exercise has the strongest evidence of therapeutic efficacy. Extracorporeal shock wave treatment, sclerosing agents as well as nitric oxide patches show promising early results but require long-term studies. Corticosteroid and nonsteroidal antiinflammatory medications have not been shown to be effective except for temporary pain relief for rotator cuff tendinopathy. Platelet-rich plasma injections show encouraging short-term results.     

Induction of tumor cell death by high hydrostatic pressure as a novel supporting technique in orthopedic surgery

As vegetative forms of microorganisms are impaired by high hydrostatic pressure (HHP) in the range of 400-600 MPa, the non-thermal inactivation of vegetative bacteria, yeasts, and moulds present in foods such as jams, fruit juices, and dressings by HHP is now well-established. Eukaryotic cells, when subjected to HHP are also damaged. In the present study, the effect of HHP on cell viability of human osteoblasts (HOB), human fibroblasts (HFB), and different tumor cell lines such as osteosarcoma cells SAOS-2, human histiocytic leukemia cells U-937, and the ovarian cancer cell line OV-MZ-6 was investigated. Therefore the different cell lines were subjected to pressures between 50 and 400 MPa and tested for viability. At HHP of 100 MPa (10 min) about 80% of the various cell lines were still alive. At 350 MPa all of the cells were damaged and dead. The three tumor cell lines investigated were slightly more resistant to HHP (50% dead at 170-193 MPa) than HOB and HFB (50% dead at 130-145 MPa). The present study demonstrates that both normal cells and tumor cells are rapidly inactivated by HHP treatment.     

Chronische Radikulopathie

Zusammenfassung Die Behandlung chronischer Rückenschmerzen mit radikulärer Symptomatik ist ein bis heute nicht gelöstes klinisches Problem. Die von Racz beschriebene Technik der perkutanen minimal-invasiven Neurolyse findet zunehmend Anwendung zur Behandlung der chronischen Radikulopathie. Es wurden 61 Patienten mit einer entsprechenden Symptomatik nach Prüfung der Ein- und Ausschlusskriterien mittels Kathetertechnik nach Racz im Bereich der lumbalen Spinalnerven behandelt. 3 und 6 Monate nach perkutaner minimal-invasiver epiduraler Neurolyse kam es zu einer deutlichen klinischen Verbesserung. Die subjektive Schmerzempfindung, quantifiziert auf dem McNab-Score, zeigte sowohl nach 3 als auch nach 6 Monaten eine deutliche Verbesserung. Mit Ausnahme einer partiellen Katheterabscherung in 2 Fällen und einer Infektion konnten keine relevanten Nebenwirkungen festgestellt werden.Die Kathetertechnik nach Racz ist zur Behandlung der chronischen Radikulopathie nach Bandscheibenoperationen oder Bandscheibenvorfällen geeignet und nebenwirkungsarm.     

Applying theory-driven approaches to understanding and modifying clinicians' behavior: what do we know?

OBJECTIVE: Despite major recent research advances, large gaps exist between accepted mental health knowledge and clinicians' real-world practices. Although hundreds of studies have successfully utilized basic behavioral science theories to understand, predict, and change patients' health behaviors, the extent to which these theories-most notably the theory of reasoned action (TRA) and its extension, the theory of planned behavior (TPB)-have been applied to understand and change clinician behavior is unclear. This article reviews the application of theory-driven approaches to understanding and changing clinician behaviors. METHODS: MEDLINE and PsycINFO databases were searched, along with bibliographies, textbooks on health behavior or public health, and references from experts, to find article titles that describe theory-driven approaches (TRA or TPB) to understanding and modifying health professionals' behavior. RESULTS: A total of 19 articles that detailed 20 studies described the use of TRA or TPB and clinicians' behavior. Eight articles describe the use of TRA or TPB with physicians, four relate to nurses, three relate to pharmacists, and two relate to health workers. Only two articles applied TRA or TPB to mental health clinicians. The body of work shows that different constructs of TRA or TPB predict intentions and behavior among different groups of clinicians and for different behaviors and guidelines. CONCLUSIONS: The number of studies on this topic is extremely limited, but they offer a rationale and a direction for future research as well as a theoretical basis for increasing the specificity and efficiency of clinician-targeted interventions.     

Implementation Intentions Facilitate Response Inhibition in Children with ADHD

Attention Deficit/Hyperactivity Disorder (ADHD) is associated with action control problems such as failure to inhibit inappropriate responses. Two studies investigated whether self-regulation by implementation intentions (if-then plans; Gollwitzer, P. M. (1999). Implementation intentions: Strong effects of simple plans. American Psychologist, 54, 493–503) facilitates response inhibition in children with ADHD. In Study 1, children with ADHD who furnished a suppression goal with implementation intentions improved inhibition of an unwanted response on a Go/No-Go task to the same level observed in children without ADHD. Study 2 showed that a combination of implementation intentions and psychostimulant medication resulted in the highest level of suppression performance in children with ADHD. Theoretical and applied implications of these results are discussed.