[Patient safety during endoprosthetic training : Does the training of surgeons in primary hip arthroplasty at certified endoprosthesis centres lead to increased complications?] / Patientensicherheit in der endoprothetischen Weiterbildung : Führt die Weiterbildung von Operateuren in der primären Hüftgelenkendoprothetik in zertifizierten Endoprothesenzentren zu vermehrten Komplikationen?

BACKGROUND: The aim of the study was to investigate whether the perioperative outcome and the operation-specific process variables in patients with total hip arthroplasty (THA) significantly deteriorate when the operation is performed by an inexperienced surgeon assisted by an experienced one in the context of a certified endoprosthesis center. MATERIAL AND METHODS: 1480 patients who received primary THA for primary coxarthrosis between 2013 and 2016 were included. The relevant data were retrospectively documented from the hospital information system, the discharge letter and the EndoCert form. The surgeons were divided according to their qualifications into experienced (senior surgeon, > 50 THA per year) and inexperienced surgeons (junior surgeon, < 50 THA per year). The collected data and measured variables were then compared based on this subdivision. RESULTS: Inexperienced surgeons showed a significant increase in the duration of the operation by 20.7 min (senior 62.6 ± 20.4 min; junior 83.3 ± 19.5 min; p ≤ 0.001), as well as the length of hospital stay by 0.25 days (senior 8.8 ± 0.9 days; junior 9.0 ± 0.9 days; p ≤ 0.001). The frequency of transfusions of red cell concentrates was significantly increased with inexperienced surgeons (senior 0.6 ± 1.1 items; junior 0.9 ± 1.4 items; p ≤ 0.001). In contrast, there was no difference in perioperative complications (p = 0.682) or in perioperative blood loss (senior 1.3 ± 0.5 l; junior 1.3 ± 0.5 l; p = 0.097). However, there was a positive correlation between the duration of the operation and blood loss (senior r = 0.183; junior r = 0.214; each p ≤ 0.01). CONCLUSION: The training of inexperienced surgeons at a certified endoprosthesis center does not lead to a reduction in patient safety or increased complications when inexperienced surgeons are assisted by experienced surgeons. Due to the extended operating time, however, there is an additional burden on the clinics in competition with non-training clinics, which is not mapped in the DRG system.

Fast track to the neocortex: A memory engram in the posterior parietal cortex.

Models of systems memory consolidation postulate a fast-learning hippocampal store and a slowly developing, stable neocortical store. Accordingly, early neocortical contributions to memory are deemed to reflect a hippocampus-driven online reinstatement of encoding activity. In contrast, we found that learning rapidly engenders an enduring memory engram in the human posterior parietal cortex. We assessed microstructural plasticity via diffusion-weighted magnetic resonance imaging as well as functional brain activity in an object-location learning task. We detected neocortical plasticity as early as 1 hour after learning and found that it was learning specific, enabled correct recall, and overlapped with memory-related functional activity. These microstructural changes persisted over 12 hours. Our results suggest that new traces can be rapidly encoded into the parietal cortex, challenging views of a slow-learning neocortex.

A simple method of measuring the wear of explanted acetabular component inserts.

AIMS: The determination of the volumetric polyethylene wear on explanted material requires complicated equipment, which is not available in many research institutions. Our aim in this study was to present and validate a method that only requires a set of polyetheretherketone balls and a laboratory balance to determine wear. METHODS: The insert to be measured was placed on a balance, and a ball of the appropriate diameter was inserted. The cavity remaining between the ball and insert caused by wear was filled with contrast medium and the weight of the contrast medium was recorded. The volume was calculated from the known density of the liquid. The precision, inter- and intraobserver reliability, were determined by four investigators on four days using nine inserts with specified wear (0.094 ml to 1.626 ml), and the intra-class correlation coefficient was calculated. The feasibility of using this method in routine clinical practice and the time required for measurement were tested on 84 explanted inserts by one investigator. RESULTS: In order to get the mean for all investigators and determinations, the deviation between the measured and specified wear was -0.08 ml (sd 0.12; -0.21 to 0.11). The interobserver reliability was 0.989 ml (95% confidence interval (CI) 0.964 to 0.997) and the intraobserver reliability was 0.941 for observer 1 (95% CI 0.846 to 0.985), 0.983 for observer 2 (95% CI 0.956 to 0.995), 0.939 for observer 3 (95% CI 0.855 to 0.984), and 0.934 for observer 4 (95% CI 0.790 to 0.984). The mean time required to examine the samples was two minutes (sd 2; 1 to 5). CONCLUSION: The method presented here was shown to be sufficiently precise for many settings and is a cost-effective and quick method of determining the volumetric wear of explanted acetabular components. However, the measurement of wear for scientific purposes will probably continue to involve more accurate and dedicated laboratory equipment.Cite this article: Bone Joint Res 2017;6:530-534.

Cementless Total Hip Arthroplasty in Primary Myelofibrosis - a Case Report.

There is a great deal of data available, in part contradictory, on the best fixation technique to use for total hip arthroplasty (THA) in hip osteoarthritis. Both the cementless and the cemented versions offer excellent long-term outcomes - if the respective technique is applied correctly. However, as far as we know, no recommendation has been made regarding cemented vs. cementless THA in primary myelofibrosis. The case described here concerns a very active 76-year-old patient with primary myelofibrosis. This is a rare hematological disease. It develops from clonal hematopoiesis with impaired blood formation and progressive bone marrow fibrosis. An MRI scan of the patients pelvis showed a marked spotted change over all of the imaged bone. Ultimately, in preoperative planning we decided in favor of a proven cementless implant (Allofit Alloclassic cup and the CLS Spotorno stem from Zimmer). Complication-free osseous integration of the cementless implants was observed. Histologic analysis of the bone showed a focally sclerotically altered bone structure. Neither osteoporosis nor osteopenia were found. In our opinion, taking into account all other indication criteria, there is no reason not to perform a cementless THA implantation in the presence of primary myelofibrosis. Key words: hip, primary myelofibrosis, cementless, THA, total hip replacement.

[Complications and costs in primary knee replacement surgery in an endoprosthetics centre : Influence of state of training]. / Komplikationen und Kosten in der primären Knieendoprothetik in einem Endoprothetikzentrum : Einfluss des Weiterbildungsstandes.

BACKGROUND: This work examines the hypothesis that in endoprosthesis implantation there are differences between experienced primary and senior caregivers (S-Op) and less experienced follow-up assistants (T-Op) with respect to process-relevant parameters. The main hypothesis is that compared to S­Op, T­Op cause significantly longer surgery times and thus additional operating theatre costs. As sub-hypotheses, differences in various perioperative (p-o) parameters between T­Op and S­Op were examined. MATERIALS AND METHODS: The status of the operator (senior and/or senior main operator [S-Op]) and/or postoperative CRP, perioperative blood loss, the amount of transfused erythrocyte concentrates, patient age, gender, ASA risk classification (American Society of Anesthesiologists), duration of surgery and blood transfusion, duration of inpatient stay, as well as the rates of early revision surgery and complications were recorded. A comparison of patients who had been operated by an S­Op and those who had been operated by a T­Op was made for all parameters. RESULTS: Significant differences were found with respect to the duration of surgery, the duration of the hospital stay, and CRP on the third p­o day. The T­Op required an average of 11 min more than the S­Op. CRP was significantly higher in the T­Op group only on the third p­o day, by 18 mg/l. In contrast, in the T­Op group, a blood loss of 181 ml was lower than in the S­Op group. This corresponded to a reduction of 0.26 transfused erythrocyte concentrates. There were no significant differences in complication rates between S­Op and T­Op. DISCUSSION: In the setting of a certified endoprosthetics centre, the comparison of T­Op with S­Op showed that the use of the former with at a non-increased complication rate led to a significant extension of the operating time. This leads to additional training costs in the amount of an estimated 3% of the current DRG remuneration. These additional costs are not represented adequately in the current remuneration system.

Noradrenaline use is not associated with extubation failure in septic patients.

Standard clinical practice recommends minimal doses of vasoactive drugs during weaning of patients from mechanical ventilation. However there are currently no clinical data to inform clinicians about whether the use of noradrenaline during weaning predisposes to weaning failure. The objective of this study was to evaluate whether the necessity of the vasopressor noradrenaline in mechanically ventilated patients recovering from septic shock changed the extubation outcome. A total of 656 patients recovering from septic shock on mechanical ventilation were selected from intensive care units in two university hospitals. Patients receiving noradrenaline at the time of weaning and case-controls not taking noradrenaline were matched for age, gender, haemodynamic and ventilatory parameters, aetiology of respiratory failure and APACHE II score. One hundred and forty-five patients who successfully tolerated a spontaneous breathing trial were extubated while on noradrenaline therapy and the reintubation rate was measured. In the noradrenaline group, the mean dose of noradrenaline during initial shock treatment was 0.52+/-0.29 microg/kg/min and 0.12+/-0.10 microg/kg/min during weaning. The reintubation rate was 12/63 (19%) in the noradrenaline group and 15/82 (18.3%) in the control group (P=1.00). Intensive care unit mortality was also similar in both groups (10/63, 15.9%) for noradrenaline patients and (11/82, 13.4%) for control patients (P=0.81). Arterial blood gases and ventilatory and haemodynamic parameters were similar in all patients regardless of weaning success. We did not find that the use of noradrenaline at the time of weaning was associated with extubation failure. Low doses of noradrenaline may not preclude weaning from mechanical ventilation.

[Solid body augmentation for comminuted calcaneal fractures : development and biomechanical testing of a hybrid osteosynthesis technique]. / Festkörperaugmentation bei Kalkaneustrümmerfrakturen : Entwicklung und biomechanische Testung einer Hybridosteosynthesetechnik.

BACKGROUND: Comminuted calcaneal fractures are a consequence of high impact trauma to the foot. Stable fixation and anatomically correct repositioning of the joint surfaces are often a problem. To improve fracture treatment, surgical techniques in combination with new augmentation materials have been tested. METHODS: This study presents a new concept of osteosynthesis of complex calcaneal fractures in combination with an alternative augmentation technique. Solid body augmentation was developed and mechanically tested against standard techniques. The solid body was used for augmentation of a central fracture void in combination with conventional plating. RESULTS: The results show a statistically significant higher stability of the new hybrid osteosynthesis concept against conventional plating techniques under in-vitro conditions. CONCLUSIONS: This work investigated a new concept of internal support of multifragmentary calcaneal fractures. Augmentation of defect voids in the calcaneus with a mechanically stable solid body implant in combination with stable screw anchorage in this implant leads to a higher stability compared to plate-fixation and augmentation with cancellous bone under in-vitro conditions.

Modifying shyness-related social behavior through symptom misattribution.

An experimental misattribution paradigm proved to be a significant intervention treatment of altering social participation among dispositionally shy women. When specific arousal symptoms previously associated with their social anxiety were misattributed to a nonpsychological source, high-frequency noise, these extremely shy women behaved as if they were not shy. Their verbal fluency and interactional assertiveness resembled that of not-shy comparison women given the same treatment. Moreover, their scores on these measures were significantly elevated from the low levels recorded by shy controls who had been led to expect shyness-irrelevant "side effects" from their exposure to noise. A male partner (a confederate) accurately perceived whether or not the women in the two control groups were shy, but he misjudged as "not shy" the shy women in the misattribution group. The greater enjoyment of the interaction by those in this latter group, despite high-frequency noise bombardment, was also reflected in their stronger preference for further affiliation than that shown by either comparison group. The continuously monitored heart rate data provide grounds for speculation as to the relationship of physiological arousal and behavior. However, a paradoxical placebo finding emerged when it appeared that the non-shy women in this same misattribution condition experienced a higher level of arousal, and this anxiety-like arousal was associated with preferences for nonaffiliation.