Ergometric evaluation of pathological gait

1983 ◽  
Vol 55 (2) ◽  
pp. 606-613 ◽  
Author(s):  
G. A. Cavagna ◽  
L. Tesio ◽  
T. Fuchimoto ◽  
N. C. Heglund
Keyword(s):  
Kinetic Energy ◽  
Sagittal Plane ◽  
Normal Subjects ◽  
Step Length ◽  
Center Of Gravity ◽  
The Body ◽  
Gravitational Potential Energy ◽  
Maximal Height ◽  
Pathological Gait ◽  
Positive Work

At each step of walking, the center of gravity of the body moves up and down and accelerates and decelerates forward with a combined movement that allows an appreciable transfer (R) between gravitational potential energy and kinetic energy, as occurs in a pendulum. The positive work and power to lift the center of gravity, to accelerate it forward, and to maintain its motion in a sagittal plane, the amount of R, the maximal height reached during each step by the center of gravity, and the step length and frequency are all determined by a microcomputer a few minutes after a subject walks on a force platform. This method is applied to the analysis of pathological gait in the attempt to measure quantitatively the alteration of the normal locomotory movement of the center of gravity. The strides of the patient are compared with the strides of normal subjects; in addition, the movement of the center of gravity of the patient during the stance on the affected limb is compared with the movement of the center of gravity during the stance on the unaffected limb, thus giving an index of the asymmetry of locomotion. biomechanics; locomotion; walking; mechanical work Submitted on January 21, 1982 Accepted on March 3, 1983

Gait style as an etiology to chronic postural pain. Part II. Postural compensatory process

1993 ◽  
Vol 83 (11) ◽  
pp. 615-624 ◽  
Author(s):  
HJ Dananberg
Keyword(s):  
Kinetic Energy ◽  
Sagittal Plane ◽  
Center Of Mass ◽  
Metatarsophalangeal Joint ◽  
Specific Pattern ◽  
The Body ◽  
First Metatarsophalangeal Joint ◽  
The Past ◽  
Compensatory Process ◽  
Methods Of Treatment

The body is designed to pull the center of mass over a single pivotal site formed by dorsiflexion of the first metatarsophalangeal joint. If this response dorsiflexion motion is blocked by functional hallux limitus, then the kinetic energy, which is created for this motion, must somehow be dissipated. The process by which this dissipation occurs creates a specific pattern of compensations which, in the past, has been seen as primary motions unrelated to sagittal plane blockade. These compensatory motions are described along with a brief section concerning the methods of treatment.

Electromyographic Study of Postural Muscles in Various Positions and Movements

1956 ◽  
Vol 186 (1) ◽  
pp. 122-126 ◽  
Author(s):  
Harold Portnoy ◽  
F. Morin
Keyword(s):  
Electrical Activity ◽  
Vertebral Column ◽  
Normal Subjects ◽  
Center Of Gravity ◽  
The Body ◽  
Lateral Flexion ◽  
Trunk Flexion ◽  
Hip Joints ◽  
Flexion And Extension ◽  
Postural Muscles

Electrical activity of ‘postural’ muscles (sacrospinales, hamstrings, gastrocnemii, quadriceps femoris) in normal subjects during different positions and movements of the body varies in different individuals. The sacrospinales become active whenever slight displacements of the center of gravity occur. The sacrospinalis of both sides participate in lateral flexion and extension, and rotation of the vertebral column. In leaning forward, these muscles (except the quadriceps) are working essentially under isometric conditions and their electrical activity is prominent. Stretch, then, appears to be a major factor for the activation of these muscles. In flexion of the trunk, the sacrospinales cease to function at a ‘critical point,’ however, further trunk flexion occurring mainly at the hip joints continues to be accompanied by the activity present in the hamstrings. In more complex movements, such as sitting and standing, the same basic mechanisms related to stretch and displacement of the center of gravity appear to hold true.

scholarly journals The phase shift between potential and kinetic energy in human walking

2020 ◽  
Vol 223 (21) ◽  
pp. jeb232645
Author(s):  
Giovanni A. Cavagna ◽  
Mario A. Legramandi
Keyword(s):  
Kinetic Energy ◽  
Potential Energy ◽  
Gravitational Potential ◽  
Sagittal Plane ◽  
Center Of Mass ◽  
Phase Relationship ◽  
Gravitational Potential Energy ◽  
External Work ◽  
Unit Distance ◽  
Factors Affecting

ABSTRACTIt is known that mechanical work to sustain walking is reduced, owing to a transfer of gravitational potential energy into kinetic energy, as in a pendulum. The factors affecting this transfer are unclear. In particular, the phase relationship between potential and kinetic energy curves of the center of mass is not known. In this study, we measured this relationship. The normalized time intervals α, between the maximum kinetic energy in the sagittal plane (Ek) and the minimum gravitational potential energy (Ep), and β, between the minimum Ek and the maximum Ep, were measured during walking at various speeds (0.5–2.5 m s−1). In our group of subjects, α=β at 1.6 m s−1, indicating that, at this speed, the time difference between Ep and Ek extremes is the same at the top and the bottom of the trajectory of the center of mass. It turns out that, at the same speed, the work done to lift the center of mass equals the work to accelerate it forwards, the Ep–Ek energy transfer approaches a maximum and the mass-specific external work per unit distance approaches a minimum.

Pendular energy transduction within the step in human walking

2002 ◽  
Vol 205 (21) ◽  
pp. 3413-3422 ◽  
Author(s):  
G. A. Cavagna ◽  
P. A. Willems ◽  
M. A. Legramandi ◽  
N. C. Heglund
Keyword(s):  
Body Weight ◽  
Kinetic Energy ◽  
Energy Transduction ◽  
The Body ◽  
African Women ◽  
Human Walking ◽  
Gravitational Potential Energy ◽  
Effective Energy ◽  
Centre Of Mass ◽  
Step Cycle

SUMMARY During walking, the centre of mass of the body moves like that of a `square wheel': with each step cycle, some of its kinetic energy, Ek, is converted into gravitational potential energy, Ep, and then back into kinetic energy. To move the centre of mass, the locomotory muscles must supply only the power required to overcome the losses occurring during this energy transduction. African women carry loads of up to 20% of their body weight on the head without increasing their energy expenditure. This occurs as a result of an unexplained, more effective energy transduction between Ek and Ep than that of Europeans. In this study we measured the value of the Ek to Ep transduction at each instant in time during the step in African women and European subjects during level walking at 3.5-5.5 km h-1, both unloaded and carrying loads spanning 20-30% of their body weight. A simulation of the changes in Ek and Ep during the step by sinusoidal curves was used for comparison. It was found that loading improves the transduction of Ep to Ek during the descent of the centre of mass. The improvement is not significant in European subjects, whereas it is highly significant in African women.

scholarly journals The Dynamics Of Quadrupedal Walking

1938 ◽  
Vol 15 (4) ◽  
pp. 522-540 ◽  
Author(s):  
JOHN T. MANTER
Keyword(s):  
Kinetic Energy ◽  
Rigid Bodies ◽  
The Body ◽  
Gravitational Potential Energy ◽  
Locomotor Apparatus ◽  
Muscle Torque ◽  
Centre Of Gravity ◽  
Individual Segment ◽  
Muscle Groups ◽  
Quadrupedal Walking

The cat was used as a representative quadruped for a study of the action of the locomotor apparatus in walking. In the analysis the body was considered as being made up of eleven parts behaving in such a fashion that they could be considered as rigid bodies. The weight of each part was determined, the position of its centre of gravity and also its moment of inertia. Moving pictures were taken of the cat walking over a specially constructed platform which recorded the pressure exerted by each foot during the stride. The photographs recorded the position of the various parts of the body at successive instants. These records were analysed in terms of displacement, velocity and acceleration of the centre of gravity of the body as a whole, and also of its parts. A comparison of vertical forces acting on single limbs of the cat during the walk shows that the reactions are greater on the forelimbs. This is not only due to the location of the centre of gravity nearer the forelimbs, but also is the result of a thrust produced at the forelimb which is largely responsible for an upward acceleration of the centre of mass of the body. Horizontal forces produced at the forefeet also tend to be greater than those at the hind. When horizontal impulse over the whole step is considered, it is shown that the forelimbs produce more retarding action, while the hindlimbs contribute more forwarding impulse to the body. The arrangement of steps is such that horizontal reactions on fore- and hindlimbs are antagonistic, thus damping fluctuations in horizontal acceleration and velocity of the centre of gravity with a probable saving in energy expenditure. The kinetic energy of the body, derived from the data of the mass and velocity of separate parts, maintains an average level but undergoes cyclical changes during the stride. A possible transfer into gravitational potential energy can account for only a part of these kinetic energy changes which are thought to involve muscle action. An analysis of the relationship between muscle forces about the joints and forces of reaction which co-operate to produce the recorded movement of an individual segment of the limbs allows the calculation of the resultant muscle torque acting on that segment. This provided actual measurements for the total muscle torque about each of the joints of the limbs at any instant. Correlation of these torques with the action of definite muscle groups indicates roughly the manner in which these muscles function in quadrupedal walking.

Body balance in a free-standing position in road and off-road cyclists

2014 ◽  
Vol 6 (4) ◽  
Author(s):  
Paulina Hebisz ◽  
Rafal Hebisz ◽  
Marek Zaton
Keyword(s):  
Sagittal Plane ◽  
Standing Position ◽  
The Body ◽  
Free Standing ◽  
Body Balance ◽  
Eyes Closed ◽  
Road Cycling ◽  
Progressive Exercise ◽  
Before And After ◽  
Road Cyclists

AbstractBackground: The purpose of this study was to compare body balance in road and off-road cyclists, immediately before and after the racing season.Material/Methods: Twenty individuals participated in the study and they were divided into two groups: specialists in road-cycling (n = 10) and in off-road cycling (n = 10). Immediately before and after the five-month racing season stabilographic trials were carried out (at rest and after progressive exercise). In assessing body balance the distance and velocity of the centre shifts (in the anterior-posterior and left-right direction) were analysed. The tests were performed with the cyclists’ eyes open, eyes closed, and in feedback.Results: After the racing season, in the off-road cyclists’ group, distance and velocity of the centre of pressure shifts increased after a progressive exercise.Conclusions: In the off-road cyclists’ group the balance of the body in the sagittal plane deteriorated after the racing season. Moreover, after the racing season off-road cyclists were characterized by a worse balance of the body, compared to road cyclists

Correction of Posture Deviations in the Sagittal Plane Using the Pilates Method

2019 ◽  
pp. 3-13
Author(s):  
Alexandru Cîtea ◽  
George-Sebastian Iacob
Keyword(s):  
Low Back Pain ◽  
Back Pain ◽  
Postural Control ◽  
Human Body ◽  
Sagittal Plane ◽  
The Body ◽  
Lower Limbs ◽  
Low Back ◽  
Pilates Method ◽  
The Relationship

Posture is commonly perceived as the relationship between the segments of the human body upright. Certain parts of the body such as the cephalic extremity, neck, torso, upper and lower limbs are involved in the final posture of the body. Musculoskeletal instabilities and reduced postural control lead to the installation of nonstructural posture deviations in all 3 anatomical planes. When we talk about the sagittal plane, it was concluded that there are 4 main types of posture deviation: hyperlordotic posture, kyphotic posture, rectitude and "sway-back" posture.Pilates method has become in the last decade a much more popular formof exercise used in rehabilitation. The Pilates method is frequently prescribed to people with low back pain due to their orientation on the stabilizing muscles of the pelvis. Pilates exercise is thus theorized to help reactivate the muscles and, by doingso, increases lumbar support, reduces pain, and improves body alignment.

Spinal Balance/Alignment—Clinical Relevance and Biomechanics

2019 ◽  
Vol 141 (7) ◽  
Author(s):  
Anoli Shah ◽  
Justin V. C. Lemans ◽  
Joseph Zavatsky ◽  
Aakash Agarwal ◽  
Moyo C. Kruyt ◽  
...  
Keyword(s):  
Social Interaction ◽  
Sagittal Balance ◽  
Sagittal Plane ◽  
The Body ◽  
Optimal Configuration ◽  
Sacral Slope ◽  
Sagittal Imbalance ◽  
Compensatory Mechanisms ◽  
Spinal Balance ◽  
Spinal Imbalance

In the anatomy of a normal spine, due to the curvatures in various regions, the C7 plumb line (C7PL) passes through the sacrum so that the head is centered over the pelvic-ball and socket hip and ankle joints. A failure to recognize malalignment in the sagittal plane can affect the patient's activity as well as social interaction due to deficient forward gaze. The sagittal balance configuration leads to the body undertaking the least muscular activities as possible necessary to maintain spinal balance. Global sagittal imbalance is energy consuming and often results in painful compensatory mechanisms that in turn negatively influence the patient's quality of life, self-image, and social interaction due to inability to maintain a horizontal gaze. Deformity, scoliosis, kyphosis, trauma, and/or surgery are some ways that this optimal configuration can be disturbed, thus requiring higher muscular activity to maintain posture and balance. Several parameters such as the thoracic kyphosis (TK), lumbar lordosis (LL), pelvic incidence (PI), sacral slope (SS), and hip and leg positions influence the sagittal balance and thus the optimal configuration of spinal alignment. This review examines the clinical and biomechanical aspects of spinal imbalance, and the biomechanics of spinal balance as dictated by deformities—ankylosing spondylitis (AS), scoliosis and kyphosis; surgical corrections—pedicle subtraction osteotomies (PSO), long segment stabilizations, and consequent postural complications like proximal and distal junctional kyphosis. The study of the biomechanics involved in spinal imbalance is relatively new and thus the literature is rather sparse. This review suggests several potential research topics in the area of spinal biomechanics.

scholarly journals Using Biofeedback to Reduce Step Length Asymmetry Impairs Dynamic Balance in People Poststroke

2021 ◽  
pp. 154596832110193
Author(s):  
Sungwoo Park ◽  
Chang Liu ◽  
Natalia Sánchez ◽  
Julie K. Tilson ◽  
Sara J. Mulroy ◽  
...  
Keyword(s):  
Angular Momentum ◽  
Sagittal Plane ◽  
Dynamic Balance ◽  
Objective Measure ◽  
Frontal Plane ◽  
Step Length ◽  
Berg Balance Scale ◽  
Whole Body ◽  
Functional Gait ◽  
Full Body

Background People poststroke often walk with a spatiotemporally asymmetric gait, due in part to sensorimotor impairments in the paretic lower extremity. Although reducing asymmetry is a common objective of rehabilitation, the effects of improving symmetry on balance are yet to be determined. Objective We established the concurrent validity of whole-body angular momentum as a measure of balance, and we determined if reducing step length asymmetry would improve balance by decreasing whole-body angular momentum. Methods We performed clinical balance assessments and measured whole-body angular momentum during walking using a full-body marker set in a sample of 36 people with chronic stroke. We then used a biofeedback-based approach to modify step length asymmetry in a subset of 15 of these individuals who had marked asymmetry and we measured the resulting changes in whole-body angular momentum. Results When participants walked without biofeedback, whole-body angular momentum in the sagittal and frontal plane was negatively correlated with scores on the Berg Balance Scale and Functional Gait Assessment supporting the validity of whole-body angular momentum as an objective measure of dynamic balance. We also observed that when participants walked more symmetrically, their whole-body angular momentum in the sagittal plane increased rather than decreased. Conclusions Voluntary reductions of step length asymmetry in people poststroke resulted in reduced measures of dynamic balance. This is consistent with the idea that after stroke, individuals might have an implicit preference not to deviate from their natural asymmetry while walking because it could compromise their balance. Clinical Trials Number: NCT03916562.

Sign in / Sign up

Export Citation Format

Share Document