The biomechanics of running. normal gait, gait disturbance. 한글 파일 자료 짱

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앞으로 읽어야 할 중요한 biomechanics review article

함께 논문 읽으면서 공부할 사람을 찾아야겠다. 

약간 어려운 분야다. 

Biomechanics and Analysis of running gait.pdf

gait(normal gait).hwp

The biomechanics of running 

Tom F. Novacheck 

Motion Analysis Laboratory, Gillette Children’s Specialty Healthcare, Uni6ersity of Minnesota, 200 E. Uni6ersity A6e., St. Paul, MN 55101, USA Received 25 August 1997; accepted 22 September 1997

biomechanics of running.pdf

Abstract

This review article summarizes the current literature regarding the analysis of running gait. It is compared to walking and sprinting. The current state of knowledge is presented as it fits in the context of the history of analysis of movement. The characteristics of the gait cycle and its relationship to potential and kinetic energy interactions are reviewed. The timing of

electromyographic activity is provided. Kinematic and kinetic data (including center of pressure measurements, raw force plate data, joint moments, and joint powers) and the impact of changes in velocity on these findings is presented. 

The status of shoewear literature, alterations in movement strategies, the role of biarticular muscles, and the springlike function of tendons are addressed. This type of information can provide insight into injury mechanisms and training strategies.

전형적인 rearfoot eversion anlge. 달리기 생체역학에서 rearfoot eversion angle은 흔히 보고되는 자료임. 

오류의 주요원천은 회전움직임을 포함. 

Fig. 5. Kinematics. These graphs show the changing position of the joint listed for one complete gait cycle in all three planes. Each graph begins and ends at initial contact and therefore represents one gait cycle along the x-axis. The vertical dashed line represents toe off for each condition. The portion of the graph to the left of the toe off line depicts joint motion during stance phase while swing phase motion is depicted to the right of the dashed line. The position of the joint or body segment in degrees is represented along the y-axis. Walking is represented by the lightly-dashed line, running the solid line, and sprinting the heavy-dashed. The corresponding toe-off line is plotted using the same line style. The

continuous line connects fifty data points (every 2% of the gait cycle) and represents average data (15 strides) for each of the three conditions. The position of the pelvis is plotted relative to the horizontal and vertical coordinate system of the lab. Hip position represents the position of the femur plotted relative to the position of the pelvis. Knee flexion-extension denotes the angle between the femur and the tibia. 0° indicates full extension (180° between the femoral and the tibial shafts). Dorsiflexion-plantarflexion is the position of the foot relative to the tibia with a 90° angle being plotted as 0°. Foot progression angle depicts the orientation of the foot relative to the lab.

Fig. 6. Sagittal plane ankle, knee, and hip motion. 6a. Ankle motion: TO timing, Elite 22%, Sprint 37%, Run 39%, Walk 62%. The three sets of slower data were collected at the Motion Analysis Laboratory at Gillette Children’s Specialty Healthcare and represent average data (15 strides) for each of the three conditions. *Elite sprinting data was adapted from Mann and Hagy [32] and represents the average of two elite sprinters with similar velocities. Dorsiflexion-plantarflexion is the position of the foot relative to the tibia with a 90° angle being plotted at 0°. 6b. Knee motion: Knee flexion-extension denotes the angle between the femur and the tibia. 0° indicates full extension (180° between the femoral and the tibial shafts). 6c. Thigh position: Thigh position denotes the position of the thigh relative to the vertical. A 0° angle indicates that the thigh is in a vertical position. This is comparable to the hip flexion:extension angle depicted in Fig. 5 except that in that case the thigh position is plotted in relation to the position of the pelvis and is, therefore, reported as a hip flexion:extension angle.

Fig. 9. Sagittal plane joint moments and powers. Joints are organized by column. For convenience, the corresponding joint motion is shown in the first row. The net joint moment is shown in the second row. Joint moments are labelled as the internal moment (some authors use the convention of labelling as the external moment). In the net joint power plots (third row) periods of power absorption are negative (deflections below the zero line) while periods of power generation are positive. Results are normalized by dividing by body weight in kg.

Normal walking Principles, basic concepts, terminology 3-dimensional clinical gait analysis(2009년)

normal gait.pdf

SUMMARY

Bipedal walking is a defining human characteristic requiring anatomical integrity and normal function of the nervous and the musculoskeletal system. Disorders affecting any level of this complex mechanism will lead to abnormal gait disturbances. Clinical assessment of gait pathology, on the other hand, implies detailed knowledge on normal gait function. Investigations to gain insight into normal walking started with the studies of Aristotel (384 BC) on the locomotion of animals followed by others in the centuries to come. Contemporary methodology on eval‎uating normal gait is based on the contribution of Inmann, Saunders, Sutherland, J. Perry, Gage and others from the early 50’s until now days.

With the introduction of instrumented gait observation they were capable to record and describe the gait movement. By applying the principles of biomechanics on locomotion they defined and measured different parameters (speed, stride length, force etc) introducing the gait terminology. 

Thus the gait cycle, that corresponds to a single stride, was established as a functional unit of normal walking. Every gait cycle is divided in two consecutive phases: stance (weight bearing) of one leg followed by swing of the same leg. Each phase is then further divided into a number of different periods. Their duration is expressed as percentage of the gait cycle. This configuration made possible the objective description of walking and the measurement of a variety of parameters at every desired time interval of the gait cycle. 

Gait assessment is performed in Gait Laboratories using video, PC, force plates, EMG and applying special software, in a procedure which is called 3-Dimensional Clinical Gait Analysis. Following a systemic methodology normal walking is recorded, displayed and validated quantitatively in the sagittal, frontal and transverse plane (3-D). Gait disturbances due to movement disorders can be captured measured and eval‎uated in comparison to normal gait patterns in order to assess the walking abilities of the patient. Gait Analysis includes Clinical Examination (medical history, clinical observation and examination etc), Kinematics Analysis, Kinetics Analysis and dynamic EMG. Kinematics refers mainly to joint, trunk and pelvis displacement trajectories, without consideration for the cause and the forces involved. Measurements are displayed in a Cartesian coordinate system diagram, where the x-axis represents time intervals expressed in percentage of the gait cycle and the y-axis joint displacements expressed in angle grades. Kinetics includes measurements of forces, both internal (produced mainly by muscle activity) and external (produced by gravity or external loads), measurements of moments across joints and work production, that cause movement. These measurements are expressed in N (Newton), Nm (Newtonmeter) and W (Watt) on the y-axis, while the the x-axis represents again time intervals of the gait cycle. In EMG Analysis muscle activity during gait is measured in mv or uv and displayed on the y-axis. At the end of the 3D Clinical Gait Analysis we are informed, in the form of diagrams and numerical quantities, about the range of motion of the joints and their abnormal deviations, the moment and work production across the joints, the functional level of the muscles involved. All data together with the clinical examination and medical history are included in the gait analysis report, where the relationships between functional deviations and gait disability are interpreted ; thus facilitating the creation of a treatment plan and a rehabilitation program to enhance walking performance of the patient and the communication between the members of the treating team as well.

Comparison of shear forces and ligament loading in the healthy and ACL-deficient knee during gait

Comparison of shear forces and ligament loading in the heal.pdf

Abstract

The purpose of this study was to predict and explain the pattern of shear force and ligament loading in the ACL-deficient knee during walking, and to compare these results to similar calculations for the healthy knee. Musculoskeletal modeling and computer simulation were combined to calculate ligament forces in the ACL-deficient knee during walking. Joint angles, ground-reaction forces, and the corresponding lower-extremity muscle forces obtained from a whole-body dynamic optimization simulation of walking were input into a second three-dimensional model of the lower extremity that represented the knee as a six degree-offreedom spatial joint. 

Anterior tibial translation (ATT) increased throughout the stance phase of gait when the model ACL was removed. The medial collateral ligament (MCL) was the primary restraint to ATT in the ACL-deficient knee. Peak force in the MCL was three times greater in the ACL-deficient knee than in the ACL-intact knee; however, peak force sustained by the MCL in the ACL-deficient knee was limited by the magnitude of the total anterior shear force applied to the tibia. A decrease in anterior tibial shear force was brought about by a decrease in the patellar tendon angle resulting from the increase in ATT. 

These results suggest that while the MCL acts as the primary restraint to ATT in the ACL-deficient knee, changes in patellar tendon angle reduce total anterior shear force at the knee.

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Neumann의 KINESIOLOGY 책 보면 도움이 많이 될거 같습니다!!! 보셨겠지만...^ ^

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못봤어요 ㅎㅎㅎ