Orthopedic Surgeons' Accuracy When Orienting an Acetabular Cup. A Comparison with Untrained Individuals.

Background and Objectives: Previous studies demonstrated a huge variability among surgeons when it comes to reproducing the position of an acetabular cup in total hip arthroplasty. Our main objective is to determine if orthopedic surgeons can replicate a given orientation on a pelvic model better than untrained individuals. Our secondary objective is to determine if experience has any influence on their ability for this task. Materials and Methods: A group of specialist orthopedic hip surgeons and a group of volunteers with no medical training were asked to reproduce three given (randomly generated) acetabular cup orientations (inclination and anteversion) on a pelvic model. Error was measured by means of a hip navigation system and comparisons between groups were made using the appropriate statistical methods. Results: The study included 107 individuals, 36 orthopedic surgeons and 71 untrained volunteers. The mean error among surgeons was slightly greater as regards both inclination (7.84 ± 5.53 vs. 6.70 ± 4.03) and anteversion (5.85 ± 4.52 vs. 5.48 ± 3.44), although statistical significance was not reached (p = 0.226 and p = 0.639, respectively). Similarly, although surgeons with more than 100 procedures a year obtained better results than those with less surgical experience (8.01 vs. 7.67 degrees of error in inclination and 5.83 vs. 5.87 in anteversion), this difference was not statistically significant, either (p = 0.852 and p = 0.981). Conclusions: No differences were found in the average error made by orthopedic surgeons and untrained individuals. Furthermore, the surgeons' cup orientation accuracy was not seen to improve significantly with experience.

Difference between Impacts of COVID-19 on Women and Men's Psychological, Social, Vulnerable Work Situations, and Economic Well-Being.

The SARS-CoV-2 virus changed social reality worldwide, affecting people's health and work life, particularly their anxiety levels. The purpose of this study is to verify the situation of women in terms of anxiety and social determinants in Spain during the pandemic. The sample consisted of 4686 people (3500 women and 1186 men). The tools used were the State-Trait Anxiety Inventory (STAI) and an ad hoc questionnaire to assess the work and mental situation of the participants. The results indicate a higher rate of anxiety among women than among men and reveal a relationship between higher levels of anxiety and more vulnerable work situations in terms of higher unemployment rates, contract changes, etc. Furthermore, there was a higher percentage of women than men in the sectors where the health crisis has had a greater impact and presence, with repercussions on the physical, mental, and social health of the entire population and especially on women. It is necessary to take into account the social determinants of health, not only at the structural level, in terms of the socio-economic and political contexts, to avoid and limit the axes of inequality such as gender.

Predictive Strength of Contextual and Personal Variables in Soccer Players' Goal Orientations.

Psychological variables, such as perceived motivational climate, goal orientation, self-determined motivation, and personality, have an influence on sports success performance. This study aimed to examine the relationships among a set of psychological variables (perceived motivational climate, goal orientation, self-determined motivation, and personality) in male and female footballers. Participants were 167 footballers (106 male, 61 female), aged 12 to 26, competing with clubs in the Spanish Football League. They all took four questionnaires aimed at evaluating motivational climate, goal orientations, self-determined motivation, and personality. The analyses of correlation and regression showed statistically significant relations among the variables. Neuroticism and psychoticism negatively relate to mastery motivational climate, the best predictor of self-determined motivation. It was concluded that contextual variables carry more weight in predicting goal orientations and self-determined motivation among participant footballers.

Enhancement of External Rotation after Latissimus Dorsi Tendon Transfer (LDTT): A Cadaveric Study.

Background and objectives: Massive rotator cuff tears compromise shoulder mobility function and cannot be directly repaired. Latissimus dorsi tendon transfer (LDTT) is a therapeutic alternative suitable for the treatment of rotator cuff tears that helps to restore external shoulder rotation. Cadaver models have been used for studying the effects of LDTT and procedural variations, but, to the best of our knowledge, none of them have been validated. The aim of our study was to validate a novel cadaver model while verifying the effects of LDTT on external rotation. Materials and Methods: Two groups were included in the study: a cadaver group and a control group made up of healthy volunteers, which were used for the validation of the cadaver model. Baseline external rotation measurements were performed with both groups, after which a massive rotator cuff tear was inflicted and repaired with LDTT in the cadaver group. Their postoperative external rotation was evaluated using three different tests. Results: No statistically significant differences were found between the baseline measurements of the two groups, and postoperative external rotation was significantly higher after LDTT in all cases but one. Conclusions: Cadaver models were validated, since they had a similar preoperative external rotation to healthy volunteers. Moreover, they allowed us to demonstrate the effect of LDTT on external shoulder rotation.

Biomechanical Behavior of an Hydroxyapatite-Coated Traditional Hip Stem and a Short One of Similar Design: Comparative Study Using Finite Element Analysis.

BACKGROUND: The objective is to compare, by the means of finite elements analysis, the biomechanical behavior of a conventional stem of proven performance with a short stem based on the same fixation principles. METHODS: A 3D femur was modeled from CT scan data, and real bone density measures were incorporated into it. Load stresses were applied to that bone in 3 different scenarios: without prosthesis, with the conventional stem, and with the short stem. Different bone loading patterns were compared by Gruen's zones both visually and statistically using Welch's test. RESULTS: The implantation of a stem generates a certain degree of stress shielding in the surrounding bone, but the pattern of the change is very similar in the compared stem models. Although there is statistical significance (P < 0.01) in the mean stress variation in most of the Gruen's zones, the magnitude of the difference is always under 2 MPa (range: 0.01 - 1.74 MPa). CONCLUSIONS: The bone loading patterns of the traditional stem and the short stem are very similar. Although there is no evidence of a link between biomechanics and clinical outcomes, our results may suggest that theoretical advantages of short stems can be exploited without the fear of altering bone loading patterns.