Pub Date : 2019-12-01DOI: 10.17489/biohun/2019/1/05
R. Gupta, R. Potalia, Pradyumna Krishna Majumdar, Parth Singh, A. Neogi
Background & Study Aims: Consensus is lacking regarding the optimal route and dose of administration of Tranexamic acid (TXA) so this study was conducted to compare the efficacy and safety of topical, oral and intravenous routes (iv) of TXA with routine hemostasis alone in patients undergoing primary total knee arthroplasty (TKA). Materials and methods: A prospective randomized trial was conducted in patients undergoing primary TKA. Patients were divided into four groups of 50 each; group 1 received intraarticular TXA, group 2 received oral TXA three hours before surgery, group 3 received IV TXA just before tourniquet release and group 4 did not receive TXA. Post-operative drain volume (PODV), fall in haemoglobin (Hb) level and the required amount of blood transfusion were evaluated. Results: PODV and drop in Hb level respectively were (158±90 ml and 1±0.5 g/dl) in group 1, (328±149 ml and 1.7±0.7 g/dl) in group 2, (311±151 ml and 2.1±1 g/dl) in group 3 and (589±115 ml and 3.2±1.2 g/dl) in group 4. The difference in drain volume between all groups was statistically significant except between groups 2 and 3. Transfusion requirements were significantly greater in group 4 (p< 0.001). Conclusions: Intra-articular, oral and IV TXA were observed to be safe strategies and more effective than tamponade effect alone to reduce drain volume and transfusion requirements after TKA. Additionally, intra-articular TXA was better than oral or IV TXA with respect to drain volume and post-op drop in Hb
{"title":"Tranexamic acid in primary total knee arthroplasty: ideal route of administration","authors":"R. Gupta, R. Potalia, Pradyumna Krishna Majumdar, Parth Singh, A. Neogi","doi":"10.17489/biohun/2019/1/05","DOIUrl":"https://doi.org/10.17489/biohun/2019/1/05","url":null,"abstract":"Background & Study Aims: Consensus is lacking regarding the optimal route and dose of administration of Tranexamic acid (TXA) so this study was conducted to compare the efficacy and safety of topical, oral and intravenous routes (iv) of TXA with routine hemostasis alone in patients undergoing primary total knee arthroplasty (TKA). Materials and methods: A prospective randomized trial was conducted in patients undergoing primary TKA. Patients were divided into four groups of 50 each; group 1 received intraarticular TXA, group 2 received oral TXA three hours before surgery, group 3 received IV TXA just before tourniquet release and group 4 did not receive TXA. Post-operative drain volume (PODV), fall in haemoglobin (Hb) level and the required amount of blood transfusion were evaluated. Results: PODV and drop in Hb level respectively were (158±90 ml and 1±0.5 g/dl) in group 1, (328±149 ml and 1.7±0.7 g/dl) in group 2, (311±151 ml and 2.1±1 g/dl) in group 3 and (589±115 ml and 3.2±1.2 g/dl) in group 4. The difference in drain volume between all groups was statistically significant except between groups 2 and 3. Transfusion requirements were significantly greater in group 4 (p< 0.001). Conclusions: Intra-articular, oral and IV TXA were observed to be safe strategies and more effective than tamponade effect alone to reduce drain volume and transfusion requirements after TKA. Additionally, intra-articular TXA was better than oral or IV TXA with respect to drain volume and post-op drop in Hb","PeriodicalId":30208,"journal":{"name":"Biomechanica Hungarica","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2019-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"41391188","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2019-12-01DOI: 10.17489/biohun/2019/1/01
M. Takács, Gergely Nagymáté, Rita M. Kiss
Purpose: No any research in literature was found to investigate the effect of pes planus on standing balance in school-aged children. Any kind of change in the arches (height, flexibility) may increase the possibility of a change in standing balance. The aim of present study is to determine the influence of pes planus on the standing balance of school-aged children based on independent time-distance and frequency based parameters. Materials and Methods: Subjects included 177 children (105 neutral and 72 with pes planus). The parameters were determined from the motion of the centre of pressure (COP) on a platform equipped with pressure gauge sensors, on which the subjects were standing for 60 seconds with both feet and open eyes. Results: When comparing the neutral and pes planus groups, none of the 17 time-distance and frequency based parameters showed any significant difference (p≥0.169). Conclusion: The results show that pes planus does not affect significantly standing balance; the differences (however not significant) between the two groups showed a poorer postural control in school-aged children with pes planus. It may be compensated by the increased ML dimension of the base of support.
{"title":"Does pes planus influence standing balance in elementary school-age children?","authors":"M. Takács, Gergely Nagymáté, Rita M. Kiss","doi":"10.17489/biohun/2019/1/01","DOIUrl":"https://doi.org/10.17489/biohun/2019/1/01","url":null,"abstract":"Purpose: No any research in literature was found to investigate the effect of pes planus on standing balance in school-aged children. Any kind of change in the arches (height, flexibility) may increase the possibility of a change in standing balance. The aim of present study is to determine the influence of pes planus on the standing balance of school-aged children based on independent time-distance and frequency based parameters. Materials and Methods: Subjects included 177 children (105 neutral and 72 with pes planus). The parameters were determined from the motion of the centre of pressure (COP) on a platform equipped with pressure gauge sensors, on which the subjects were standing for 60 seconds with both feet and open eyes. Results: When comparing the neutral and pes planus groups, none of the 17 time-distance and frequency based parameters showed any significant difference (p≥0.169). Conclusion: The results show that pes planus does not affect significantly standing balance; the differences (however not significant) between the two groups showed a poorer postural control in school-aged children with pes planus. It may be compensated by the increased ML dimension of the base of support.","PeriodicalId":30208,"journal":{"name":"Biomechanica Hungarica","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2019-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"46869007","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2019-12-01DOI: 10.17489/biohun/2019/1/04
Ágnes Ureczki, K. Keszei
Due to its properties like high load-bearing capacity, biocompatibility, excellent abrasion resistance and strength, ultra-high molecular weight polyethylene (UHMWPE) is widely used as a bearing material in the field of joint prostheses. Currently, UHMWPE is produced by compression molding, ram extrusion or sintering, followed by post-processing techniques, such as milling or machining to finalize the prosthesis geometry and to achieve the final tolerances. With post-processing techniques we are wasting a high cost material, energy and time. In this paper, we collected manufacturing technologies that has have the potential to be used for creating prosthesis with one step production, minimalize material loss and with a view to providing customized manufacturing capabilities. We compared three technologies: (i) ram extrusion (currently used technology for joint prosthesis), (ii) FDM printing and (iii) injection molding. In addition to the feasibility, we focus on the investigation of mechanical properties. Three tests were performed on the manufactured specimens: hardness measurement, tensile test and scanning electron microscope (SEM) to compare the finished parts produced by the different processing technologies.
{"title":"Prospects in innovative manufacturing technology of UHMWPE for prostheses and comparison with medical grade UHMWPE","authors":"Ágnes Ureczki, K. Keszei","doi":"10.17489/biohun/2019/1/04","DOIUrl":"https://doi.org/10.17489/biohun/2019/1/04","url":null,"abstract":"Due to its properties like high load-bearing capacity, biocompatibility, excellent abrasion resistance and strength, ultra-high molecular weight polyethylene (UHMWPE) is widely used as a bearing material in the field of joint prostheses. Currently, UHMWPE is produced by compression molding, ram extrusion or sintering, followed by post-processing techniques, such as milling or machining to finalize the prosthesis geometry and to achieve the final tolerances. With post-processing techniques we are wasting a high cost material, energy and time. In this paper, we collected manufacturing technologies that has have the potential to be used for creating prosthesis with one step production, minimalize material loss and with a view to providing customized manufacturing capabilities. We compared three technologies: (i) ram extrusion (currently used technology for joint prosthesis), (ii) FDM printing and (iii) injection molding. In addition to the feasibility, we focus on the investigation of mechanical properties. Three tests were performed on the manufactured specimens: hardness measurement, tensile test and scanning electron microscope (SEM) to compare the finished parts produced by the different processing technologies.","PeriodicalId":30208,"journal":{"name":"Biomechanica Hungarica","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2019-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"45394934","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2019-06-01DOI: 10.17489/biohun/2019/1/03
Wenguang Li
Obstructive jaundice in the biliary tract can infect blood and result in mortality with a high rate. Percutaneous transhepatic biliary drainage (PTBD) with catheters is a useful solution discharging the obstructive jaundice. However, the elements of fluid mechanics showing clinical performance of a PTBD catheter have been documented little so far. In the article, empirical relationships between bile flow rate and pressure gradient in PTBD catheters were studied in terms of equivalent friction factor for the first time. Firstly, an equivalent friction factor in a catheter was raised and determined based on existing in vitro experimental data of bile flow through the catheters with different materials, various inner diameters and lengths under various pressure differences. Then, an empirical correlation of bile flow rate through a catheter was established based on pressure gradient, inner diameter and bile viscosity. The correlation was used to identify effects of catheter inner diameter and bile viscosity on the bile flow rate under the physiological bile pressure difference across obstructed common bile ducts. The feature of minor hydraulic losses in the catheters was clarified, too. The proposed equivalent friction factor was proportional to Reynolds number in a power of -0.654 in comparison with a power of -1 for the fully developed laminar flow in circular pipes. The bile flow rate through a catheter was proportional to inner diameter, kinematic viscosity, and pressure gradient in the powers of 3.2, -0.5 and 0.74, respectively. The minor hydraulic losses could be significant when Reynolds number was greater than 100.
{"title":"The elements of fluid mechanics of bile flow through biliary drainage catheters","authors":"Wenguang Li","doi":"10.17489/biohun/2019/1/03","DOIUrl":"https://doi.org/10.17489/biohun/2019/1/03","url":null,"abstract":"Obstructive jaundice in the biliary tract can infect blood and result in mortality with a high rate. Percutaneous transhepatic biliary drainage (PTBD) with catheters is a useful solution discharging the obstructive jaundice. However, the elements of fluid mechanics showing clinical performance of a PTBD catheter have been documented little so far. In the article, empirical relationships between bile flow rate and pressure gradient in PTBD catheters were studied in terms of equivalent friction factor for the first time. Firstly, an equivalent friction factor in a catheter was raised and determined based on existing in vitro experimental data of bile flow through the catheters with different materials, various inner diameters and lengths under various pressure differences. Then, an empirical correlation of bile flow rate through a catheter was established based on pressure gradient, inner diameter and bile viscosity. The correlation was used to identify effects of catheter inner diameter and bile viscosity on the bile flow rate under the physiological bile pressure difference across obstructed common bile ducts. The feature of minor hydraulic losses in the catheters was clarified, too. The proposed equivalent friction factor was proportional to Reynolds number in a power of -0.654 in comparison with a power of -1 for the fully developed laminar flow in circular pipes. The bile flow rate through a catheter was proportional to inner diameter, kinematic viscosity, and pressure gradient in the powers of 3.2, -0.5 and 0.74, respectively. The minor hydraulic losses could be significant when Reynolds number was greater than 100.","PeriodicalId":30208,"journal":{"name":"Biomechanica Hungarica","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2019-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"41430171","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2019-01-01DOI: 10.17489/biohun/2019/1/0h
Rita Kiss M.
{"title":"Vezércikk","authors":"Rita Kiss M.","doi":"10.17489/biohun/2019/1/0h","DOIUrl":"https://doi.org/10.17489/biohun/2019/1/0h","url":null,"abstract":"","PeriodicalId":30208,"journal":{"name":"Biomechanica Hungarica","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2019-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"46560549","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Our kinesiologist focus is on the active elongation of spine. This very simple movement like active spine elongation makes measurable different in sagittal curves, that would be detect-ed with Spinal Mouse electromechanical device. It detects the datas about gait parameters from the cervical 7 to sacral 1 vertebra’s processus spinosus about every movement segment in sagittal plane and spine length too. We had tested that on 27 persons: (n =13) men and (n=14) women, (n=9) of them were competent in elongation. The purpose of this study was to verify the change of spine length withal thoracic kyphosis and lumbar lordosis during active elongation in the vertebral column and conclude deep vertebral stabilizer muscle-func-tion, regarding the voluntary contraction of multifidii muscles. Furthermore to improve therapeutic approaches in the spinal control of the biomechanical centre, called lumbopelvic segment. The ideal gait of human creates a big debate in the physiotherapeutic or the movement professions. Although the physiological posture should be given the basic means of the trunk-stabilization exercises. Our results prove significant effect of elongation on the spine. It was success to verify the rel-evancy (p = 0,001) of elongation-practised i.e. non-start person compared to start ones (they had used active spine elongation first time in their life) in the length of spine. Significant augmentation (p = 0,02) was given between normal own spine length and elongated length. Significant decrease (p = 0,001) was measured between normal/own thoracic kyphosis and the elongated kyphosys, but didn’t shown significant difference (p = 0,24) in the sagittal curve of lumbar spine. But we could experience clear reduction of lordosis in both group (p = 0,917) and segmentally as well. We can deduce from lumbar orientation and spinal control effect and even that this Spinal Mouse can’t be the right device to prove the real meaning of elongation in the lumbar spine, because of its neuromuscular (muscle tone) and biomechanical nature (degree of freedom).
{"title":"Acute effect of active elongating technique on the morphological characteristics of the spine","authors":"Judith Kondor, Anna Széll, J. Tihanyi","doi":"10.17489/2018/2/05","DOIUrl":"https://doi.org/10.17489/2018/2/05","url":null,"abstract":"Our kinesiologist focus is on the active elongation of spine. This very simple movement like active spine elongation makes measurable different in sagittal curves, that would be detect-ed with Spinal Mouse electromechanical device. It detects the datas about gait parameters from the cervical 7 to sacral 1 vertebra’s processus spinosus about every movement segment in sagittal plane and spine length too. We had tested that on 27 persons: (n =13) men and (n=14) women, (n=9) of them were competent in elongation. The purpose of this study was to verify the change of spine length withal thoracic kyphosis and lumbar lordosis during active elongation in the vertebral column and conclude deep vertebral stabilizer muscle-func-tion, regarding the voluntary contraction of multifidii muscles. Furthermore to improve therapeutic approaches in the spinal control of the biomechanical centre, called lumbopelvic segment. The ideal gait of human creates a big debate in the physiotherapeutic or the movement professions. Although the physiological posture should be given the basic means of the trunk-stabilization exercises. Our results prove significant effect of elongation on the spine. It was success to verify the rel-evancy (p = 0,001) of elongation-practised i.e. non-start person compared to start ones (they had used active spine elongation first time in their life) in the length of spine. Significant augmentation (p = 0,02) was given between normal own spine length and elongated length. Significant decrease (p = 0,001) was measured between normal/own thoracic kyphosis and the elongated kyphosys, but didn’t shown significant difference (p = 0,24) in the sagittal curve of lumbar spine. But we could experience clear reduction of lordosis in both group (p = 0,917) and segmentally as well. We can deduce from lumbar orientation and spinal control effect and even that this Spinal Mouse can’t be the right device to prove the real meaning of elongation in the lumbar spine, because of its neuromuscular (muscle tone) and biomechanical nature (degree of freedom).","PeriodicalId":30208,"journal":{"name":"Biomechanica Hungarica","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2018-11-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"48846919","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Realization of material laws in accordance with the bone’s material properties carried out by additive manufacturing technologies","authors":"P. Ficzere, L. Borbás, G. Falk","doi":"10.17489/2018/2/11","DOIUrl":"https://doi.org/10.17489/2018/2/11","url":null,"abstract":"","PeriodicalId":30208,"journal":{"name":"Biomechanica Hungarica","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2018-11-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"45298288","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
The goals of our study were to evaluate the biomechanical differences between five tendons and the changes in biomechanical properties caused by low cycle fatigue loading. Achilles, quadriceps, semitendinosus + gracilis (STG), tibialis anterior (TA) and the peroneus longus (PL) were harvested from 8 donors. The grafts were removed and placed in a radio-cryopro-tectant solution and slowly cooled and stored at -78 °C. The load was defined as a sinusoid function, the starting values are assigned to a peak load of 250 N and a minimum load of 0 N. Data was recorded in the 2th, 4th, 8th, 16th, 32nd, 64th, 128th, 256th, 515th and 1000th cycle. In the given cycles the whole measured waveform was registered. Young modulus of elasticity was calculated. To compare the biomechanical behavior of the different tendons the Young’s modulus values were evaluated in the 64th, 128th, 256th, 512th and 1000th cycles. While in case of PL and STG tendons the change is apperantly linear in the investigated range, in case of the Achilles, quadriceps and TA tendons there is a region where a significant change in modulus occurs.
{"title":"Stiffening effect of human tendons during strain controlled fatigue loading","authors":"G. Szebényi, D. Faragó, R. Kiss, K. Pap","doi":"10.17489/2018/2/09","DOIUrl":"https://doi.org/10.17489/2018/2/09","url":null,"abstract":"The goals of our study were to evaluate the biomechanical differences between five tendons and the changes in biomechanical properties caused by low cycle fatigue loading. Achilles, quadriceps, semitendinosus + gracilis (STG), tibialis anterior (TA) and the peroneus longus (PL) were harvested from 8 donors. The grafts were removed and placed in a radio-cryopro-tectant solution and slowly cooled and stored at -78 °C. The load was defined as a sinusoid function, the starting values are assigned to a peak load of 250 N and a minimum load of 0 N. Data was recorded in the 2th, 4th, 8th, 16th, 32nd, 64th, 128th, 256th, 515th and 1000th cycle. In the given cycles the whole measured waveform was registered. Young modulus of elasticity was calculated. To compare the biomechanical behavior of the different tendons the Young’s modulus values were evaluated in the 64th, 128th, 256th, 512th and 1000th cycles. While in case of PL and STG tendons the change is apperantly linear in the investigated range, in case of the Achilles, quadriceps and TA tendons there is a region where a significant change in modulus occurs.","PeriodicalId":30208,"journal":{"name":"Biomechanica Hungarica","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2018-11-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"48212916","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Measure the effectiveness of lymphoedema treatment by gait analysis","authors":"K. Hampel, Zsófia Pálya, R. Kiss","doi":"10.17489/2018/2/01","DOIUrl":"https://doi.org/10.17489/2018/2/01","url":null,"abstract":"","PeriodicalId":30208,"journal":{"name":"Biomechanica Hungarica","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2018-11-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"45155783","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Examining equilibrium role of visual and vestibular systems in the case of dancers and women without a dance experience","authors":"Fanni Dulházi, B. Kopper, J. Tihanyi","doi":"10.17489/2018/2/04","DOIUrl":"https://doi.org/10.17489/2018/2/04","url":null,"abstract":"","PeriodicalId":30208,"journal":{"name":"Biomechanica Hungarica","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2018-11-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"48989525","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
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