Background: The use of computer assisted surgery, navigation (NAV) in shoulder arthroplasty is still under discussion, regarding the clinical outcome and prosthesis longevity, especially when combining these factors with cost, time and surgeon’s experience. Beside the NAV, there has been in use patient-specific instrumentation (PSI) as an additional tool for more precise glenoid implant position. Surgical NAV and PSI for glenoid implant positioning in anatomic and reverse total shoulder arthroplasty are in last years under observation and discussion. Objective: To critically review and evaluate the current literature regarding the use of computer navigation and PSI in shoulder arthroplasty. Methods: Critical review of the existing literature. Results: Cost-effectiveness, prosthesis longevity and revision arthroplasty rate have not yet been proven clinically. Moreover, heterogeneity is high in studies that include different positioning systems (NAV, PSI and standard instrumentation). Heterogeneity is due to differences in surgical technique, implants, surgeon’s expertise, radiographic image analysis technique. Conclusion: The use of navigation systems and PSI should be clinically proven in the shoulder arthroplasty. Independent experts’ opinion and independent high level studies lack at the moment. There will be still a lot of talk regarding this topic in future.

Background: A precise three-point shot (3S) is considered a key parameter of success in a basketball game, and therefore the factors that affect its success have always attracted the attention of researchers. Aim: The aim of this research was a biomechanical-mathematical analysis of 3S in basketball, in order to determine the key parameters for performing a 3S. Results: The research shows a model of shooting a basketball player from the central position of the shot with 6.75 m. The modeling led to the conclusion that the height of the throw, the speed and the angle of the throw of the ball have a positive and direct relationship with the angle at which the ball falls into the basket when it comes to a shot for three points. Conclusion: The height of the throw, the speed and the angle of the ball have a positive and direct relationship with the angle at which the ball hits the basket when it comes to a shot for three points. Anthropometric characteristics of the player, such as the length of the arm, and the height of the player, directly lead to a positive relationship with the throwing angle.

Summary Study aim: The body structure can play a determining role in the achievement of top judo performance, and it seems to influence the type of techniques applied. The aim of this study is to determine the somatotypes in male and female national level judokas across weight categories in order to observe possible differences among athletes. Material and methods: A total of 61 male judokas (23.2 ± 2.7 years old) and 37 female judokas (22.3 ± 3.3 years old) participated in this study. Anthropometric variables were used to calculate somatotypes. Somatotypes were determined according to the Heath-Carter method. Analysis of variance and Tukey’s post hoc test were used to determine differences between weight categories and obtained effect sizes (η2) were presented as well. Results: Somatotype differences among weight categories in male and female judokas were observed. Generally, all categories could be classified in three somatotypes in male and female athletes. Conclusions: The lightest categories were recognized as mesomorphic ectomorphs in females with an exception in the –48 kg category, and ectomorphic mesomorphs in male athletes. The middle ones had the endomorphic mesomorph somatotype and the heaviest athletes presented somewhat more extreme cases of endomorphic mesomorphs, both in male and female judokas. According to the results obtained, judokas have a specific body composition in different weight categories. Therefore, coaches could create a specific training programme for athletes who belong to different somatotypes.

Abstract The objectives of this research were to establish somatotype and hand-grip strength between elite cadet male and female sambo athletes divided by weight categories. A total of 97 elite cadet sambo athletes, participants of the World Cadets Sambo Championships 2018 participated in the study. Male and female sambo athletes were divided by official weight categories. Anthropometrical variables were taken in order to calculate somatotypes and hand-grip strength. A one-way analysis of variance and Tukey's post hoc tests were used to compare group differences by weight categories. Results of this study provide the first description of somatotype and hand-grip strength of elite male and female cadet sambo athletes in relation to weight category. A typical somatotype in male sambo athletes was endomorphic mesomorphs with a predominance of musculoskeletal tissue, while female athletes differed concerning weight category. Overall, an increase in handgrip strength across weight categories was noted. Hand-grip strength increases linearly from the lightest to the heaviest weight category except in −66 and −84 kg in male athletes. Differences in handgrip strength of female athletes were detected between the lightest group and last six groups in all three variables in favor of last six as well as −44 and kg −48 kg compared with the heaviest. To the best of our knowledge, this study provides the first normative data of somatotype and hand-grip strength analyses in relation to age, gender, and weight categories of cadet sambo athletes. The anthropometric profile of sambo athletes changed according to their weight category. Mesomorphy was the most dominant somatotype component in male athletes, while female had three different types of somatotype component in relation to weight category. In conclusion, we found differences in hand-grip strength related to weight category, which can be linked to the muscle mass of athletes. Future studies should focus on somatotype and strength handgrip values of international compared to national level sambo athletes.

Background: The problem of heavy school bags is a global problem recognized in many countries in Europe and the world, including in Bosnia and Herzegovina. In addition to poor posture habits, "sedentary lifestyles" and insufficient physical activity, school bags is one of the main causes of low back pain and deformity in pupils. The recommendation of the World Health Organization (WHO) is that the weight of the school bag should not exceed 10% of the student's weight. However, in practice these limitations are far from reality with the obvious problems caused by too heavy bags. The aim of the paper is to identify and analyze the backbone load caused by the overweight school backpacks in real school work conditions and eliminate them by creating new solutions that are in line with ergonomic and biomechanical principles, as well as the recommendation given by WHO. Methods: The research included first grade primary school students at the age of seven, including their parents. The research began by interviewing parents with relevant questions, as well as measuring the students’ height and weight and the weight of their school backpacks. The analysis was performed in CATIA v5 software package (Dassault Systemes, Velizy-Villacoublay, France) using its advanced biomechanical modules. By knowing the anthropometric and work environment data with ergonomic design and analysis, the biomechanical analysis, rapid upper limb assessment (RULA) and carry analysis were performed. Results: The conducted survey showed that 84% of students walk from home to school nineteen minutes on average and that 77% of them carry their school backpacks independently. Based on the measurements, it has been shown that, on average, the weight of the school backpacks is well above the WHO recommendation. A study conducted on a representative sample of students confirmed the relation between fatigue and spinal pain caused by carrying a heavy school bag. Computer analysis showed excessive loads on the spinal segment of L4/L5 that were outside the normal range of 3,400 N. Conclusions: A simulated computer analysis using RULA and biomechanical analysis with calculations of maximum loads in the lumbar segment of students found that school backpacks carried by students were too heavy for their age and well beyond the normal limits and WHO recommendations. The analysis showed that it is necessary to reduce the weight of the bag by about 30%.

Background: The aim of the article was to create an appropriate computer model based on the real status of the mortar operator's workplace and to analyze the workplace. After that, for any possible exceedances from the aspect of the organism's load and safety, the aim is to redesign the workplace and bring it within the limits of the permissible load, and therefore the required safety. The aim is also to identify the characteristic work movements performed by the soldier and to carry out an ergonomic analysis of the soldier's efforts and to propose appropriate improvements. Methods: The analysis is performed on a total of 20 soldiers, from which is determined an average model of the following characteristics: 180 cm in height and 85 kg in weight. The task is to take a mine from the shell containing the mines, then transfer it to the mortar and fill the mortar barrel. The weight of the 120 mm mortar grenade is 14.8 kg. The average soldier is 26 years old and his military exercise lasts 4 hours. The CATIA software package (Dassault Systemes, Velizy-Villacoublay, France) is used for analysis. By knowing the anthropometric and work environment data, with ergonomic design and analysis, the following analyses were made: biomechanical analysis, rapid upper limb assessment (RULA) and carry analysis (option from CATIA software). Results: The proposed modification of the position resulted in a decrease in the L4/L5 torque from 316 Nm to 154 Nm along with decreasing of the compression force on the L4/ L5 from 5779 N to 3038 N (the compression force allowed is 3400 N), and while the RULA analysis is from the red color position 1 (score 7; maximum load requiring rapid repositioning of such position), revised final score 4 made in yellow (a solution acceptable for this work place). Conclusions: By ergonomic analysis, obtained proposal will lead to less chance of injury, prevention of burn out syndrome, fewer chances of illness, decreasing the fatigue, greater safety, less energy spent and better preparedness for all necessary tasks.

Introduction: Neuralgic amyotrophy (NA) or Parsonage Turner syndrome is a clinical syndrome characterized by sudden attack of neuropathic pain, motor weakness and sensory loss that could be more or less clinically present. Different interpretations regarding the differential diagnosis, symptoms, cause and treatment were given till now. Aim: We report our experience with a 66-year-old male who had a sudden pain attack and palsy in shoulder region, without sensory loss, and associated calcific tendinitis of rotator cuff and degenerative changes in cervical spine. Case report: Patient came to our hospital with strong pain in shoulder area and signs of frozen shoulder. Active abduction and anteflexion was only to 30 degrees. He experienced the intense pain with visual analogue scale (VAS) 10/10 a night before, during his sleep. No trauma. Neurontin (gabapentin) was given to the patient. After 4 days, he felt better with abduction and anteflexion to 90 degrees. After 2 weeks VAS was 3/10, abduction and anteflection to 100 degrees. Conclusion: Neuralgic amyotrophy (NA) is a self-limiting inflammatory disorder usually with idiopathic etiology. The condition can be challenging to treat since many associated symptoms and diagnostic tests and procedures may mimic NA. In that case, accurate differential diagnosis is essential.

Introduction: Achilles tendon injuries usually occur with abrupt movements at the level of the ankle and foot, and the consequence is the overload of the Achilles tendon. Aim: Examine the Achilles tendon load as a function of the landing angle, and find the critical point at which the tendon overload begins and when a further increase in the landing angle can lead to rupture. Methods: The study has a prospective character. The input data represent the anthropometric values of the respondents, who are professional basketball players in the senior national team of Bosnia and Herzegovina and were processed in the CATIA v5-6 software solution. Software data processing analyzed the landing angles and the transfer of force to the Achilles tendon. The end result is a regression curve, which projects the angle at which the Achilles tendon is overloaded, and indicates an increased risk of possible injury to the tendon itself. Results: The onset of overloading starts at an angle of 32.28° and at an angle of 35.75° the overloaded load occurs, indicating the need for the subject to change the position of the foot to prevent damage to the tendon itself. Conclusion: An angle of 35.75° is the critical point at which the Achilles tendons are overloaded at the very landing. Prevention of injury should go in the direction of practicing the feet for a particular position at the time of the landing, and in the direction to develop adequate footwear that would mitigate the angle at the landing.

Introduction: Spleen acts as blood reservoir both in animals and human beings. Spleen contracts during the exercise and so augment the systemic circulation and helps body to maintain longer on high intensity exercise. Reviewing all available literature, the human spleen shows a decrease in volume, in range from 8% to 56%, depending on the work intensity. Aim: To evaluate the percentage of the decrease in splenic volume after the treadmill exercise at specific workloads: aerobic threshold intensity, anaerobic threshold intensity, submaximal intensity and maximal intensity. Methods: This prospective study with repeated measurements included 16 healthy subjects, divided in two groups. First group consisted of 8 elite long-distance runners and second group of 8 recreational runners. First testing consisted of treadmill ergospirometry test. This data was crucial for the second testing where subjects were exercising on treadmill at specific workloads. Four specific workloads were determined: treadmill exercise at aerobic threshold intensity (1st workload), anaerobic threshold intensity (2nd workload), submaximal intensity (3rd workload) and maximal intensity (4th workload). Workloads were controlled by the speed of treadmill, for each subject individually regarding the ergospirometry test. Ultrasound measurement of spleen was done before and after each workload. Results: Elite long-distance runners showed greater spleen contraction than recreational runners after four workloads. Spleen contraction was the biggest after the 3rd workload in elite long-distance runners. Smallest contraction was in group of recreational runners after the 1st workload. Statistically significant difference was not found between the groups, regarding the splenic volume after exercise at four specific workloads (p>0.05). Conclusion: Elite long-distance runners had greater decrease in splenic volume than recreational runners, after exercise at four specific workloads, without significant difference. Greatest decrease happened in elite long-distance runners, after exercise at submaximal intensity - 49% decrease in splenic volume.