Osteoarthritis of the knee is common and often leads to significant physical disability. While classic conservative therapeutic approaches aim for symptoms like pain and inflammation, procedures like the intraarticular application of hyaluronic acids (HA) or platelet-rich plasma (PRP) are thought to stimulate the endogenous HA production, stop catabolism of cartilage tissue, and promote tissue regeneration. To analyse whether the positive effects of PRP injections are associated with the level of cartilage damage, patient satisfaction with the treatment was correlated with the level of knee joint osteoarthritis quantified by MRI. PRP was performed with a low-leukocyte autologous conditioned plasma (ACP) system in 59 patients. A pre-treatment MRI was performed and a Whole-Organ MRI Score (WORMS) was used to score the level of knee osteoarthritis by 14 features: integrity of the cartilage, affection of the bone marrow, subcortical cysts, bone attrition, osteophytes, integrity of the menisci and ligaments, presence of synovitis, loose bodies, and periarticular cysts. A multivariate analysis with ordinary least squares regressions was used. Although pain symptoms and severity of clinical osteoarthritis symptoms decreased, regression analysis could not detect a correlation between the degree of cartilage damage measured by the WORMS score and a positive response to PRP therapy. This study suggests that intraarticular injection of PRP might improve osteoarthritis symptoms and reduces the pain in patients suffering from osteoarthritis of the knee joint independent from the level of cartilage damages quantified by the whole-organ MRI scoring method WORMS.

Hallux valgus disease is a common deformity of the forefoot. There are currently more than 100 surgical approaches for operative treatment. Because hypermobility of the first tarsometatarsal joint is considered to be causal for hallux valgus disease, fusion of the tarsometatarsal joint is an upcoming surgical procedure. Despite the development of new and increasingly stable fixation devices like different locking plates, malunion rates have been reported in 5 to 15% of cases. Biomechanical comparison of three commonly used fixation devices (a dorsal locking plate, a plantar locking plate, and an intramedullary fixation device) was performed by weight-bearing simulation tests on synthetic bones. Initial compression force and stiffness during simulation of postoperative weight-bearing were analysed. Fixation of the first tarsometatarsal joint with the plantar plate combination demonstrated a higher stiffness compared to fixation with the intramedullary implant or the medial locking plate. The intramedullary device provided the highest initial compression force. Failure was detected in the following ranking: (1) the angle-stable intramedullary fixation device, (2) the medial located plate, and (3) the plantar locking plate. The intramedullary device demonstrated the highest initial compression force of the three tested implants. The plantar locking plate showed the best overall stability during weight-bearing simulation. Further clinical research is necessary to analyse if the intramedullary fixation device needs a longer period of non-weight-bearing to reach a better non-union rate compared to the plantar locking plate.

University spin-offs (USOs) are an important driver for innovation, along with economic and social development. Hence, understanding which factors help them perform successfully is crucial, especially regarding their peculiarities in a scientific environment. This study focuses on essential factors such as team composition and diversity in USOs in the biotech sector in 64 founding teams in Switzerland and Germany. By identifying the team composition, and going beyond the usual team characteristics, along with checking in parallel for network and financing effects, the paper adds empirical evidence to the ongoing debate if and how team diversity in USOs affects the performance of this special group of newly founded firms. We test our hypotheses with the partial least squares method (PLS). Our results from the mediation model show how the diversity of teams is related to networks and financial resources and affects the performance. In addition, our study reveals the direct and indirect effects of team diversity on success in USOs. This way we contribute to the ongoing discussion on performance investigating the sources of team effects more in detail.

The main objective of every new development in total hip arthroplasty (THA) is the longest possible survival of the implant. Periprosthetic stress shielding is a scientifically proven phenomenon which leads to inadvertent bone loss. So far, many studies have analysed whether implanting different hip stem prostheses result in significant preservation of bone stock. The aim of this preclinical study was to investigate design-depended differences of the stress shielding effect after implantation of a selection of short-stem THA-prostheses that are currently available. Based on computerised tomography (CT), a finite elements (FE) model was generated and a virtual THA was performed with different stem designs of the implant. Stems were chosen by osteotomy level at the femoral neck (collum, partial collum, trochanter sparing, trochanter harming). Analyses were performed with previously validated FE models to identify changes in the strain energy density (SED). In the trochanteric region, only the collum-type stem demonstrated a biomechanical behaviour similar to the native femur. In contrast, no difference in biomechanical behaviour was found between partial collum, trochanter harming and trochanter sparing models. All of the short stem-prostheses showed lower stress-shielding than a standard stem. Based on the results of this study, we cannot confirm that the design of current short stem THA-implants leads to a different stress shielding effect with regard to the level of osteotomy. Somehow unexpected, we found a bone stock protection in metadiaphyseal bone by simulating a more distal approach for osteotomy. Further clinical and biomechanical research including long-term results is needed to understand the influence of short-stem THA on bone remodelling and to find the optimal stem-design for a reduction of the stress shielding effect.

This paper examines gender differences in organizational performance after a business succession process in family firms considering social and liberal feminist theories. We use OLS regressions with data from German-speaking European countries to analyse how male and female family business successors perform in terms of the objective and subjective performance indicators of sales, employees, sales per employee, growth prospects regarding sales growth, market share growth, overall return growth, equity ratio growth, innovation, and satisfaction scale. We observe that business succession is gendered. Female successors realize revenues equal to those of the male successors but employ, on average, significantly more employees. For the productivity index of sales per employee, we observe that female successors realize a lower productivity compared to men. The subjective performance indicators of growth prospects and satisfaction scale show no gender differences in terms of business succession. We discuss these differences in terms of gender discrimination and the gendered perception of performance to provide unbiased explanatory approaches. We deny the female underperformance hypothesis and show that women are equally capable of managing the business transfer in family business successfully. The results underline the need for an increased consideration of female company successors to close the succession gap. Cet article examine les différences de genre dans le rendement organisationnel après un processus de succession d’entreprise dans les entreprises familiales, en tenant compte des théories féministes sociales et libérales. Nous utilisons la régression OLS avec des données provenant de pays européens germanophones pour analyser les performances des successeurs masculins et féminins dans les entreprises familiales en termes d’indicateurs objectifs et subjectifs de performance du chiffre d’affaires, des salariés, du chiffre d’affaires par salarié, des perspectives de croissance du chiffre d’affaires, des parts de marché, du rendement global, du ratio de fonds propres, de l’innovation et de l’échelle de satisfaction. Nous observons que la succession d’entreprise est sexospécifique. Les successeurs de sexe féminin réalisent des gains égaux à ceux des successeurs masculins mais emploient, en moyenne, beaucoup plus de personnel. Concernant l’indice de productivité du chiffre d’affaires par employé, nous observons que les successeurs de sexe féminin ont une productivité inférieure à celle des hommes. Les indicateurs subjectifs de perspectives de croissance et l’échelle de satisfaction ne montrent aucune différence entre les sexes, en termes de succession d’entreprise. Nous abordons ces différences en termes de discrimination fondée sur le genre et de perception sexospécifique de la performance afin de fournir des approches explicatives impartiales. Nous rejetons l’hypothèse de la sous-performance féminine et montrons que les femmes sont également capables de gérer avec succès la transmission d’entreprise dans les entreprises familiales. Les résultats soulignent la nécessité de la prise en compte accrue des successeurs de sexe féminin dans les entreprises afin de combler l’écart de succession.

This paper examines the impact of weather phenomena on the German stock market, evaluating cloud cover, humidity, air pressure, precipitation, temperature, and wind speed as weather variables. We use stock market data (returns, trading volume, and volatility) from the DAX, MDAX, SDAX, and TecDAX for the period from 2003 to 2017 and show, with modern time-series (GARCH) models that air pressure is the only weather variable that exerts a potentially consistent effect on the stock market. Air pressure reduces the trading volume on the SDAX and TecDAX, and changes in air pressure lead to increases in returns on the DAX, MDAX and SDAX. The effects of the other weather variables show no clear pattern and are critically discussed. In addition, this article contains an overview of the historical research results on the effects of weather on stock markets.