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: Noise represent an unwanted sound that endangers human health in multiple manners and in work setting causes reduction of productivity on one side, and increased waste on the other. Noise pollution occurs when the ear is exposed to the volume of sound that is disturbing, stressful or directly damaging hearing, but also acting on the organism as a whole. Aim: The aim of the article is to examine the vulnerability of workers working on the „press“ machine, and to carry out an analysis and examine the press operator workplace, then perform the noise spread measurement in the press operator work area and compare the current measurements with the permissible levels and analyze the time period of worker exposure, as well as presentation of the effects of noise on productivity and workers health. The aim of the article also includes the proposal for decrease of noise pollution. Methods: A noise analysis at the workplace of workers working on a „press“ machine was performed, which is exposed to a high impulse noise due to which the quality and quantity of production are reduced. For the purpose of calculating the noise level for one working day at the press operator site 1, 2 and 3, it is necessary to analyze the noise level in time. Operators spend most of their working hours at stations 1 and 3 where the measured noise level is Lm1 = 94.7 dB is taken, or at position 3, Lm3 = 97.2 dB. The measured noise level at these locations without the operation of the press is Lm1 = 80.1 dB, or at station 3 is Lm3 = 80.1 dB. Results: It was found that these operators working on the machine in question were exposed to a noise over the limit for more than three years. Their health problems that arise as a result of noise exposure are documented in their health charts. In order to achieve uninterrupted work at the press machine, during the eight hours shift, a noise correction is required to allow the equivalent sound level to fall within one day to the permissible 85 dB. In this regard, we consider the fact that we have known that the press produces a sound level of 110 dB, and that there is a reverberation (reflecting) sound. Given the technical characteristics of the plant, the reduction of the sound intensity of the source itself is not possible, so the suggestions of the technical solution will be based on reduced reflected sounds and to prevent the spread of direct sound to the operator. Conclusion: Workers are exposed to permanent noise during a working day, which produces a number of consequences for the health of the worker, but also the employer and the community. The imperative of the employer is to reduce the number of rejects, increase profitability and to have a positive impact on the health of the individual.

The problem related to the inadequate position of workers during lifting heavy loads is the everyday life of many environments, such as industrial halls or warehouses, which often results in the deepening of the worker's spine load problem. An analysis of such a workplace was carried out in this paper. The workloads at specific body zones were determined, whether they were within the prescribed limits or exceeded it, and on that basis a redesign of the workspace was made in accordance to the anthropological values of the model.

Introduction: : Diastasis recti abdominis is consequence of mechanical forces that, proportionally to uterus and fetus augmentation, make pressure on anterior abdominal wall. Muscle tonus in pregnancy is significantly impaired. Stress relaxation of connective tissues and modified statics often cause back and leg pain. Aim: To evaluate whether pregnancy augment the spinal column and abdominal muscles loading and to what extent, based on anthropometric measurements and software analysis. Methods: Twenty women participated in the study, having similar anthropometric measurements. Average height was 170 cm (mean), and weight 68.0 kg (mean). Three working postures were analyzed: upright (working posture 1), semi-bent (working posture 2) and bent (working posture 3) working postures by both non-pregnant and pregnant women. Simulation was made in software package CATIA. Results: Analysis was done for working postures at workplace in pre-pregnancy period (height 170 cm, weight 68 kg) and during pregnancy (height 170 cm, weight 80 kg). From analysis of posture 2 and posture 3 in pregnant woman, conclusion can be drawn that despite of the fact that our examinees did not carry any external/additional loads, in these two working postures the abdominal muscles suffered overloading. Conclusion: It is crucial to strengthen the entire musculature for women who wish to get pregnant. The pre-pregnancy exercises might improve the posture, tonus and boost chances for safe labor and delivery. Strong abdominal muscles are needed to unload the spine. It is highly recommended to prepare their musculature for pregnancy through various pre-pregnancy exercises.

Introduction: Most everyday activities, performed over a long period leads to performance degradation of skeletal muscles as well as spinal column which is reflected in the reduction of maximum force, reduction of the speed of response, reducing control of the movement etc. Although until now many mathematical models of muscles are developed, very small number takes into account the fatigue, and those models that take into account changes in the characteristics of muscles for extended activities, generally considered tiring under certain conditions. Given that the current models of muscle fatigue under arbitrary conditions of activation and load are very limited, this article presents a new model that includes scale of muscles overload. Material and Methods: There are three female cardiac surgeons working performing these surgeries in operating rooms, and their average anthropometric measures for this population is: a) Weight: 62 kg; b) Height: 166 cm. Age: 45 taken in the calculation within the CATIA software, that entity is entitled to 50% of healthy female population that is able to execute these and similar jobs. During the surgery is investigated the two most common positions: position “1” and “2”. We wish to emphasize that the experiment or surgical procedure lasted for two positions for five hours, with the position “1” lasted 0.5 hours, and position “2” lasted about 4.5 hours. The additional load arm during surgery is about 1.0 kg. Results: The analysis was done in three positions: “Operating position 1”, “Operating position 2 ‘, and each of these positions will be considered in its characteristic segments. These segments are: when the body takes the correct position, but is not yet burdened with external load, then when the surgeon receives the load and the third position when the load is lifted at the end of the position. Calculation of internal energy used on the joints is carried out in the context of software analysis of this model using CATIA R5v19. The proposed model is based on CATIA software model, which consists of visual indicators of the burden on certain parts of the body as well as the forces acting in these parts of the body. Conclusion: Based on these indicators to define which muscles, as well as that part of the skeletal system is overloaded, what is the position and what needs to be done that specific load be within permitted limits.

Ključne riječi: biomehanika, opterećenost, kralježnica, softverski paket SAŽETAK: Radno djelovanje zahtijeva stalno mijenjanje položaja da bi se udovoljilo potrebama raznih aktivnosti koje čovjek obavlja tijekom izvršavanja radnih zadataka. Ako se rad obavlja u radnom prostoru koji nije pravilno dizajniran, dolazi do zamora, smanjenja učinkovitosti rada i ugrožavanja zdravlja. Rad predstavlja analizu mogućnosti poboljšanja postojećeg radnog položaja kod ispitanika i proračuna istih vrijednosti sila i momenata na L4 i L5 pršljena kralježnice kao i naprezanja kod određene skupine mišića za radnika u poznatom radnom procesu u odnosu na dopuštena naprezanja. UDK 616.71-001:613.65 PRIMLJENO: 19.11.2013. PRIHVAĆENO: 24.3.2014. OPTEREĆENOST KRALJEŽNICE U FUNKCIJI POKRETA F. Veljović, F. Veljović* SIGURNOST 56 (2) 141 147 (2014)

Background and Purpose: In this study surface electromyography (sEMG) was used as stand alone acquisition tool in order to emphasize possibilities of sEMG utilization as a screening tool for ergonomic purposes. We presented comparison for task completion variations based on processed sEMG data, where sEMG was used as muscular activity screening tool with the objective to offer decision in the most convenient task variation. In this context, muscular activity screening used in this paper was based primarily on muscular activity index and its transformations, where such data were correlated with electrical energy induced by activated muscle groups. Material and Methods: Analysis of two different approaches to the fixed medical table and upper trunk alignment with table surface as the final target is performed for this purpose. Surface EMG signals were recorded using an eight-channel fiber optic TELEMG system (BTS S.p.a.) sampling at a frequency of 1000 Hz for selected muscles of right body side alone, in order to maximize muscular activity overview. If set otherwise (for both body sides), 8 available channel electrodes reduced the number of monitored muscle groups to 4 for each body side, causing decreased comparability and objectivity of muscular activity screening. Results and Conclusion: Finally, after benchmarking task routines, Model 2 as routine approach was less demanding than Model 1, muscular activity index as equivalent to energy or work done over time in the monitored muscles was suitable for the purpose of muscular activity estimation, but should be expressed with consideration of muscular activity duration as muscle energy expenditure per time unit. Despite its imperfections, sEMG may be exploited as stand alone and as complement to other available acquisition and analysis tools.

U radu su prikazani rezultati istraživanja provedenog na zaposlenicima HEP – Operatora distribucijskog sustava d.o.o., Elektre Zagreb, pri izvođenju radova na visini. Utvrđeni rezultati ukazuju na napore i na ucestale nefizioloske položaje tijela koji se javljaju kod navedenih radova. Rezultati upucuju na potrebu primjene novih pristupa u izradi postupaka penjanja i izvođenja radova na visini zbog pravilnog i svrsishodnog trosenja energije uložene u rad, smanjenja zamora i olaksanje rada, cime bi se utjecalo na bolje uvjete rada, postigla veca sigurnost i zdravlje radnika, ali i veca produktivnost rad.