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Changes in postural stability on balance platform in patients after meniscal repair – two years follow up

Żmijewska Kinga, Fąfara Alicja, Feluś Jarosław, Mikos Magdalena, Nawara Jolanta, Gądek Artur

Acta of Bioengineering and Biomechanics

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2021

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Vol. 23, no. 4

75--83

EN

Purpose: The aim of this work was to evaluate postural stability on the balance platform averagely 2 years following meniscal repair. Methods: This is a retrospective, case-control comparative analysis of patients who underwent surgical repair for the isolated longitudinal traumatic meniscal tear versus matched healthy controls. The study group consisted of 30 patients (mean age 29.93 years; averagely 2.3 years after surgery) and the control group – of 30 people. Following physical examination and completion of the IKDC, and the Lysholm questionnaires, the evaluation of the postural stability using two single-leg stabilometry tests was performed. In the static test, the analyzed variables included deviations from the horizontal, vertical axes and the length of the balance path travelled. In the dynamic test, the length of the path travelled and the time to complete task were recorded. Between-limb and between-groups comparison of collected stabilometry tests were performed. Additionally, the IKDC and the Lysholm questionnaires scores were compared between the study and heathy groups. Results: No abnormalities were found on clinical examination in the study group nor any differences between the operated and contralateral knee (p > 0.05). In stabilometry: (1) in the study group, the operated extremity scored worse than the contralateral limb (length of path traveled in: A) static test x = 56.7 cm SD = 37.91 cm vs. x = 21.6 cm SD = 9.06 cm; p = 0.002 and B) dynamic test x = 82.57 cm, SD = 50.43 cm vs. x = 53.32 cm, SD = 13.82 cm; p = 0.003); (2) In the control group, no leg-related differences were noted (p > 0.05); (3) Between-group comparison revealed that the study group scored worse than the control group (length of path traveled in: A) static test x = 56.7 cm, SD = 37.91 cm vs. x = 17.23 cm, SD = 3.39 cm; p = 0.001 and B) dynamic test x = 82.57 cm, SD = 50.43 cm vs. x = 32.13 cm, SD = 9.41 cm; p < 0.001). Study group scored worse on IKDC scores (p < 0.001) but not on Lysholm score ( p > 0.05). Conclusions: Postural stability deficit persists despite a successful meniscal repair.

2

Układ wylotowy typu kolana sprężarki promieniowej i osiowo-promieniowej

Antas Stanisław

Zeszyty Naukowe Politechniki Rzeszowskiej. Mechanika

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2020

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z. 92 [300]

29--43

PL

Kolano jest układem wylotowym kanału przepływowego sprężarki promieniowej i osiowo-odśrodkowej, w którym następuje zmiana kierunku przepływu z promieniowego na kierunek wyznaczony przez oś dyfuzora komory spalania. W pracy przedstawiono metodę wyznaczania parametrów strumienia w przekroju wyjściowym układu wylotowego sprężarki promieniowej i osiowo-odśrodkowej. Analiza obejmuje układ wylotowy typu kolana. Zaprezentowano także odpowiednią metodę określania parametrów geometrycznych dla kanału wylotowego tego typu. Wymienione metody mogą być stosowane w trakcie realizacji projektu koncepcyjnego sprężarki, a oparto je na równaniu zachowania energii, równaniu ciągłości przepływu, pierwszej i drugiej zasadzie termodynamiki oraz funkcjach gazodynamicznych i definicjach używanych w teorii maszyn wirnikowych. Końcowa część pracy zawiera zasady doboru obliczeniowej wartości sprężu sprężarki z promieniowym dyfuzorem łopatkowym oraz wnioski.

3

Physiological parameters analysis of transfemoral amputees with different prosthetic knees

Li Sujiao, Cao Wujing, Yu Hongliu, Meng Qiaoling, Chen Wenming

Acta of Bioengineering and Biomechanics

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2019

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Vol. 21, no. 3

135--142

EN

Physiological parameters analysis allows for a precise quantification of energy expenditure of transfemoral amputees with different prosthetic knees. Comparative physiological parameters analysis that indicate the functional characteristics of knee joints is essential to the choice of transfemoral amputee. The aim of this study was to propose a microprocessor-controlled prosthetic knee (i-KNEE) and conducted physiological parameters (energy cost, gait efficiency and relative exercise intensity) comparison of transfemoral amputees with C-leg, Rheo Knee and Mauch under different walking speeds. Methodsː A microprocessor-controlled prosthetic knee with hydraulic damper (i-KNEE) was developed. A two-factor repeated measurement experiment design was used. Each subject was instructed to accept the same treatments. The two factors were type of prosthetic knees (the i-KNEE, the C-Leg, the Rheo Knee and the Mauch) and speed (0.5, 0.7, 0.9, 1.1, 1.3 m/s). The energy cost, gait efficiency and relative exercise intensity of ten transfemoral amputees were measured. Resultsː For all the prosthetic knees, the energy cost increased along with walking speed. There was no significant difference between three microprocessor-controlled prosthetic knees in energy cost. The gait efficiency of Mauch was always less than or equal to other three microprocessor-controlled prosthetic knees in specific walking speed. The relative exercise intensity increased with speed for all the prosthetic knees. More effort was needed for the transfemoral amputees with Mauch than other three microprocessorcontrolled prosthetic knees in the same walking speed. Conclusionsː The use of the microprocessor-controlled knee joints resulted in reduced energy cost, improved gait efficiency and smaller relative exercise intensity.

4

Comparison of results of ACL reconstruction using LARS method and autogenous ST/GR graft

Płocki Jędrzej, Pelikan Piotr, Bejer Agnieszka, Granek Arkadiusz, Krawczyk-Suszek Marlena, Kotela Ireneusz

Acta of Bioengineering and Biomechanics

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2019

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Vol. 21, no. 1

113--119

EN

The objective of the study was assessment of the function of the knee joint after ACL reconstruction using the LARS method and autogenous graft. The study was of a retrospective character and included 96 patients who had undergone reconstruction of the torn ACL. The study was conducted within 36–48 months after surgery. Methods: In order to compare the results of the ACL reconstruction performed with 2 types of grafts, the following instruments were used: Lysholm Knee Scoring Scale, SF 36v2 questionnaire for assessment of health-related quality of life, and Biodex System 4 for isokinetic muscle testing. Results: No differences in the evaluation of the quality of life measured using SF 36v2 questionnaire were observed between the LARS and ST GR groups. Using the Lysholm Scale, the distribution of knee function scores was compared according to the type of surgery. There are no grounds to confirm the differences in the distribution of knee function scores considering the type of graft ( p = 0.756). Isokinetic test showed a significant weakening of muscle strength in the operated limb, compared to the strength of the healthy limb. Conclusions: The type of graft used for ACL reconstruction does not exert an effect on the quality of life of patients or the level of their knee joint function. Extensor and flexor muscles strength of the knee joint was lower in the operated limb, irrespective of the type of graft used. Weak relationships were observed between the level of knee joint function and extensor muscle strength of this joint.

5

Assessment of postural stability in patients after reconstruction of the anterior cruciate ligament with LARS and autogenous graft

Plocki J., Kotela I., Bejer A., Pelikan P., Granek A., Krawczyk-Suszek M.

Acta of Bioengineering and Biomechanics

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2018

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Vol. 20, no. 4

9--14

EN

The aim of the study was to assess static balance after reconstruction of the anterior cruciate ligament (ACL), using gracialis tendons graft (GR) or semi-tendinosus (ST), compared to patients treated with the Ligament Advanced Reinforcement System (LARS). The study was performed within 36 to 48 months after the surgery. Methods: The study included 96 patients. The LARS group consisted of 44 patients, control group operated with ST/GR tendons included 52 patients. The stabilometric platform Alpha was used to assess the static balance. Two 30-second trials in the double-leg stance position with eyes opened and closed were performed. The distribution of loads in a free standing was also assessed. Results: In the test with open eyes the subjects from the LARS group had a significantly longer center of pressure (COP) path, a higher mean velocity, a greater mean COP sway in foot in the lateral direction and a larger path area occupied by the COP graph. During the tests with eyes closed, a significant difference occurred in the mean displacement of COP in lateral direction – greater in the LARS group. In addition, all parameters deteriorated during the tests with eyes closed in both groups. Conclusions: In static balance assessed with eyes closed, more proprioceptive deficits may appear in the LARS group.

6

The morphology of the articular surfaces of biological knee joints provides essential guidance for the construction of functional knee endoprostheses

Nagerl H., Dathe H., Fiedler Ch., Gowers L., Kirsch S., Kubein-Meesenburg D., Dumont C., Wachowski M. M.

Acta of Bioengineering and Biomechanics

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2015

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Vol. 17, no. 2

45--53

EN

Purpose: In comparative examinations of kinematics of the knees of humans and pigs in flexional/extensional motion under compressive loads, the significant differential geometric essentials of articular guidance are elaborated to criticise the shaping of the articular surfaces of conventional knee-endoprostheses and to suggest constructional outlines that allow the endoprosthesis to adopt natural knee kinematics. Implantation is discussed with regard to the remaining ligamentous apparatus. Methods: Twelve fresh pig knee joints and 19 preserved human knee joints were moved into several flexional/extensional positions. In each joint, the tibia and femur were repeatably caught by metal plates. After removing all ligaments, the tibia and femur were again caught in these positions, and their points of contact were marked on both articular surfaces. Along the marker points, a thin lead wire was glued onto each surface. The positions and shapes of the four contact lines were mapped by teleradiography. Results: All contact lines were found to be plane curves. The medial and lateral planes were parallel, thus defining the joint’s sagittal plane. In the human knee, as compared to the lateral, the medial femoral contact line was always shifted anteriorly by several millimetres. The tibial contact curve was laterally convex and medially concave. In the pig knees, the lateral and medial contact lines were asymmetrically placed. Both tibial curves were convex. Conclusions: Both knees represent cam mechanisms (with one degree of freedom) that produce rolling of the articular surfaces during the stance phase. Implantation requires preservation of the anterior cruciate ligament, and ligamentous balancing is disadvantageous.

7

Torque of the shank rotating muscles in patients with knee joint injuries

Hrycyna M., Zieliński J.

Acta of Bioengineering and Biomechanics

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2011

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Vol. 13, no. 4

77-83

EN

The aim of the study was to evaluate the torque of the shank rotating muscles in patients with reconstructed anterior cruciate ligament (ACL) and rehabilitation accomplished in comparison with a control group. The study was carried out on the group of 187 males. For the purpose of the study a prototype testing device for the shank rotating muscles' torque under static conditions was used. The study was based on the measurement of maximal torque at selected angles (-30 degree, 0 degree, 45 degree) of the shank rotation as well as on the angle (30 degree, 60 degree, 90 degree) of flexion of the knee joint. The results obtained in the group with reconstructed anterior cruciate ligament (ACL) and rehabilitation accomplished were comparable to those the control group and mostly of no statistical significance. Lack of significant differences between the values of shank rotating muscles' torque achieved in an injured limb compared to an uninjured one may testify to an effective rehabilitation process. The results of the research can serve as a diagnostic tool for the rehabilitation process development.

8

The influence of knee marker placement error on evaluation of gait kinematic parameters

Szczerbik E., Kalinowska M.

Acta of Bioengineering and Biomechanics

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2011

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Vol. 13, no. 3

43-46

EN

Vicon motion system is an accurate equipment for objective gait analysis. According to clinical experience the most important source of errors in kinematics is marker misplacement. It seems that knee marker placement is especially important because of its direct influence on two body segments: thigh and shank. There is little data in the literature on how the misplacement of knee marker determines the changes of kinematic parameters. Therefore the aim of this study was to collect the kinematic data of subjects with different knee pathologies (one with knee flexion contracture, the second with knee hyperextension) while knee marker position was changed in a systematical way. They were walking with their natural, preferred speed. The data were collected using VICON460 motion system, the Helen Hayes marker set and Plug-In-Gait model. Then they were processed based on Polygon software. The results of both subjects showed the changes of kinematics, depending on the knee marker misplacement. The assessed joint ranges of angle change were: in knee, 18° in sagittal plane and 20° in frontal plane; in hip, 10° in sagittal plane and 24° in transversal plane; in ankle, 10° in sagittal plane and 25° in transversal plane. This paper presents the detailed data which could help the users of such systems to interpret the kinematic data.

9

Patellar tracking in the total knee joint replacement model

Jansova M., Kren J., Pokorny J., Koudela K., Koudela Jr. K.

Modelling and Optimization of Physical Systems

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2010

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z. 9

37--40

EN

The study aims to identify the key points that affect the patello-femoral joint stability and stress distribution. The finite element model of the knee joint is used. The femoral component is rotated along the mechanical axis for 5 degrees both medially and laterally. The stress pressure distribution is analyzed within patello-femoral joint during gait cycle.

CS

Tato práce si klade za cíl urćeni klíćových faktorů ovlivňujících stabilitu patelo-femorálního kloubniho spojení a rozloženi napěti v tomto spojení. Je použit konečně-prvkový model kolenního kloubu. Femorální část náhrady je otáčena kołem mechanické osy o 5 stupňů jak mediálně tak laterálně. Nakonec je provedena analýza rozložení napětí na patelo-femorálním kloubu během chůze.

10

The influence of the surface treatment on the increased durability of the frictional elements of endoprostheses

Gierzyńska-Dolna M., Adamus J., Lacki P., Wiśniewska-Weinert H.

Zeszyty Naukowe Katedry Mechaniki Stosowanej / Politechnika Śląska

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2006

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z. 26

111-116

EN

In the paper the leading wear processes of hip and knee endoprostheses are discussed. Selected results of the tribological tests are given. The influence of the surface treatment on wear of T?6A14V titanium alloy was determined. Additionally, the test results of wear products are given.

11

Geometrical modeling of knee joint including anatomic properties

Borkowski P., Sowiński T., Kwiatkowski K., Skalski K., Żabicka M., Polczyński M.

Zeszyty Naukowe Katedry Mechaniki Stosowanej / Politechnika Śląska

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2006

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z. 26

40-46

EN

Presently, CT is one of the most common and accessible methods of human internal structure research. Current programmes for tomographic data processing of data logged from tomography projection allow generation of three-dimensional images of organs. These reconstructions show that they are usually suitable for a precise preparation of surgical procedure operation planning, particularly in the case of joints. In the paper, basic methodology of that kind is shown on the example of a knee joint. The methodology leads to obtaining individual three dimensional models of large human joints. Analysis of tomographic data and creation of the three-dimensional model of the joint was conducted with use of MIMICS.

12

Movement of the lower leg and patella - dynamic model

Jurkojć J., Tejszerska D.

Zeszyty Naukowe Katedry Mechaniki Stosowanej / Politechnika Śląska

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2002

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z. 19

81-86

EN

The 2D model of human knee is presented in this paper. The anterior and posterior cruciate ligaments, medial and lateral collateral ligaments, patellar ligament and the most important muscles causing movement of lower leg relatively to femur are taken into account. Model enables determination of muscular forces, forces in ligaments, forces between tibia and femur and between patella and femur.

PL

W pracy przedstawiony został dwuwymiarowy model kolana. Uwzględnione zostały więzadła krzyżowe, poboczne, więzadło rzepki i najważniejsze dla ruchu podudzia względem uda mięśnie. Model umożliwia wyznaczenie sił mięśniowych, sił w więzadłach oraz sił reakcji pomiędzy podudziem i udem oraz pomiędzy rzepką i udem.