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1

Anatomical protocol for gait analysis: joint kinematics measurement and its repeatability

Żuk M., Trzeciak M.

Journal of Theoretical and Applied Mechanics

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2017

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Vol. 55 nr 1

369--376

EN

International Society of Biomechanics has proposed a general reporting standard for joint kinematics based on anatomical reference frames. Nevertheless, the gait analysis protocols based on this standard are still poorly reported. The purpose of the current study is to propose and preliminarily assess the potential of an anatomically based ISB 6-DOF protocol, which combines the ISB reporting standard together with a marker cluster technique. The proposed technical marker set enables full description of the lower limb kinematics (including three-dimensional ankle-foot complex rotations) according to the current biomechanical recommendation. The marker set provides a clinically acceptable inter-trial repeatability and minimal equipment requirements.

2

Three-dimensional kinematic adaptations of gait throughout pregnancy and post-partum

Branco M. A. C., Santos-Rocha R., Vieira F., Aguiar R., Veloso A. P.

Acta of Bioengineering and Biomechanics

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2016

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Vol. 18, no. 2

153--162

EN

Purpose: The kinematic analysis of gait during pregnancy provides more information about the anatomical changes and contributes to exercise and rehabilitation prescription. The purposes were to describe and quantify the spatial, temporal and kinematic parameters in the joints of the lower limb during gait at the end of the first, second and third trimesters of pregnancy and in the postpartum period. Methods: A three-dimensional analysis was performed in eleven pregnant women. Repeated measures ANOVA was performed for comparisons between periods. Results: The longitudinal effect of pregnancy was not observed in spatial and temporal parameters. In joint kinematics the effect of pregnancy was observed in all joints for the three planes of motion. The hip joint and pelvis are the structures with more changes, and the results point to an increase in the anterior tilt of the pelvis as the pregnancy progresses, as well as a decrease of the amplitudes of the hip joint. The results suggested that pregnant women need to maintain the stability of the body, and become more efficient in locomotion. Conclusions: In general, the results retrieve the values from the beginning of pregnancy, indicating that the body was self-organized in order to overcome the morphological and physiological changes which women suffer during pregnancy, indicating that they have the ability to adapt depending on the demands, and after the effect of pregnancy is over, they return to values similar to those found in early pregnancy

3

The upper ankle joint: Curvature morphology of the articulating surfaces and physiological function

Nägerl H., Kubein-Meesenburg D., Fanghänel J., Dathe H., Dumont C., Wachowski M. M.

Acta of Bioengineering and Biomechanics

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2016

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Vol. 18, no. 3

83--90

EN

Purpose: The curvature morphology of the articulating surfaces determines the physiological movement pattern. We quantitatively examined the curvature morphology of the tibiotalar articulating surfaces and specified their geometric contact patterns. Methods: Geometrically equivalent cartographic nets were marked on the talar and tibial articulating surfaces of true-to-scale moldings of 20 human ankle joints (intervals of 5 mm) to relate corresponding articulating units of the surfaces. The corresponding contours of the net lines were compared, and the incongruity of articulating surfaces could thus be quantified locally. Results: All tibial sagittal net lines represented circular arcs. Along the sagittal talar net lines, the curvature radii increased medially from anterior to posterior but decreased laterally. Each net line could be approximated by three circular arcs. Examining these three parts of the talar net lines, the anterior sagittal curvature radii increased from medial to lateral, whereas the posterior radii decreased. The tibial and talar transversal net lines were congruent. The articulation surfaces showed a transversal contact line in every dorsal/plantar joint position. The degree of local congruity was solely ascertained by the incongruity of the corresponding sagittal net lines. The maximal degrees of congruity were found laterally for dorsal flexion, laterally/centrally for neutral joint position, and centrally/medially for plantar flexion. Conclusions: By the transversal line contact, the contact area is broadened over the articulating surfaces from lateral to medial. In dorsal flexion, compressive loads are mainly transferred by lateral/anterior zones and in plantar flexion by medial/posterior zones of the articulating surfaces. Reconstruction of the transversal contact line is essential.

4

Evaluation of functional methods for human movement modelling

Gastaldi L., Lisco G., Pastarelli S.

Acta of Bioengineering and Biomechanics

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2015

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Vol. 17, no. 4

31--38

EN

Purpose: accurate assessment of human joint parameters is a critical issue for the quantitative movement analysis, due to a direct influence on motion patterns. In this study three different known functional methods are experimentally compared to identify knee joint kinematics for further gait and motion analysis purposes. Methods: taking into account the human knee physiology complexity, within its roto-translation, the study is conducted on a lower limb mechanical analogue with a polycentric hinge-based kinematic model. The device mimics a joint with a mobile axis of rotation whose position is definable. Sets of reflective markers are placed on the dummy and flexion-extension movements are imposed to the shank segment. Marker positions are acquired using an optoelectronic motion capture system (Vicon 512). Results: acquired markers’ positions are used as input data to the three functional methods considered. These ones approximate the polycentric knee joint with a fixed single axis model. Different ranges of motion and number of markers are considered for each functional method. Results are presented through the evaluation of accuracy and precision concerning both misalignment and distance errors between the estimated axis of rotation and the instantaneous polycentric one, used as reference. Conclusion: the study shows the feasibility of the identification of joint parameters with functional approaches applied on a polycentric mechanism, differently from those usually conceived by the reviewed algorithms. Moreover, it quantifies and compares the approximation errors using different algorithms, by varying number and position of markers, as well ranges of motion.

5

A computer graphics system for the analysis of joint kinematics

Van Sint Jan S., Clapworthy G., Rooze M.

Machine Graphics and Vision

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1999

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Vol. 8, No. 1

55-62

EN

The paper describes a system to diagnose disorders related to joint kinematics. By the use of a multidisciplinary approach, including medical imaging, three-dimensional reconstruction, kinematics and computer graphics, the system provides simultaneous visualization of both the three-dimensional morphology and the three-dimensional motion of a joint for which the kinematics parameters have been experimentally interpolated from medical imaging. Applications planned for the future include both an interactive diagnisis system for joint disorders and a system to illustrate normal and pathological joint kinematics to medical students.