A Convenient Flexion-Extension Leg Support for Nerve Surgery of the Lower Extremity

1946 ◽  
Vol 99 (1) ◽  
pp. 32-33
Author(s):  
Ivan W. Brown
Keyword(s):  
Lower Extremity ◽  
Flexion Extension ◽  
Nerve Surgery

Prototype design and size optimization of a hybrid lower extremity exoskeleton with a scissor mechanism for load-carrying augmentation

2014 ◽  
Vol 229 (1) ◽  
pp. 155-167 ◽  
Author(s):  
Yunjie Miao ◽  
Feng Gao ◽  
Dalei Pan
Keyword(s):  
Lower Extremity ◽  
Influence Coefficient ◽  
Input And Output ◽  
Flexion Extension ◽  
Load Carrying ◽  
Influence Coefficient Method ◽  
Prototype Design ◽  
Coefficient Method ◽  
Length Optimization ◽  
Scissor Mechanism

A hybrid lower extremity exoskeleton SJTU-EX which adopts a scissor mechanism as the hip and knee flexion/extension joint is proposed in Shanghai Jiao Tong University to augment load carrying for walking. The load supporting capabilities of a traditional serially connected mechanism and the scissor mechanism are compared in detail. The kinematic influence coefficient method of the kinematic and dynamic analysis is applied in the length optimization of the scissor sides to minimize the transmitting errors between the input and output motions in walking and the load capacities of different scissor mechanisms are illustrated. The optimization results are then verified by the walking simulations. Finally, the prototype of SJTU-EX is implemented with several improvements to enhance the working performances.

scholarly journals Triceps to biceps transfer for restoration of elbow flexion following upper brachial plexus injury

2017 ◽  
Vol 50 (01) ◽  
pp. 035-042
Author(s):  
Pothula Durga Prasada Rao ◽  
Rayidi Venkata Koteswara Rao ◽  
R. Srikanth
Keyword(s):  
Brachial Plexus ◽  
Brachial Plexus Injury ◽  
Biceps Tendon ◽  
Elbow Flexion ◽  
Triceps Muscle ◽  
Grade 5 ◽  
Muscle Transfers ◽  
Flexion Extension ◽  
Grade 3 ◽  
Nerve Surgery

ABSTRACT Introduction: Upper brachial plexus injury in adults causes loss of elbow fl exion; when the primary nerve surgery has failed or the patient seeks treatment after 12 months of injury and pedicled muscle transfers are required. Most commonly, the latissimus dorsi or the Steindler flexorplasty is used. Material and Methods: We have transferred one of the heads of triceps muscle to restore the elbow flexion in such cases. In addition to return of elbow flexion, extension of elbow following surgery is retained. Ten patients suffering from upper brachial plexus injuries underwent transfer of one head of triceps to biceps tendon between December 2011 and August 2015. Results: The recovery of elbow flexion was Grade 5 in 1, Grade 4 in 4 and Grade 3 in 2; only three of the ten patients had no functionally useful elbow flexion. Seven of the ten patients had an adequate elbow extension following the procedure.

Timing of Lower Extremity Motions during Barefoot and Shod Running at Three Velocities

2000 ◽  
Vol 16 (2) ◽  
pp. 169-179 ◽  
Author(s):  
Brigit De Wit ◽  
Dirk De Clercq
Keyword(s):  
Knee Joint ◽  
Lower Extremity ◽  
Linear Method ◽  
Knee Extension ◽  
Joint Movement ◽  
Relative Time ◽  
General Linear Method ◽  
Alternative Approach ◽  
Flexion Extension ◽  
Male Subjects

This study investigates the timing differences between subtalar and knee joint movement of 9 male subjects while running barefoot and shod at three velocities. An alternative approach is used by dividing the pronation curve into 3 phases. Consequently, the timing of the maximum pronation phase was evaluated, not just the event of the maximum pronation value. Statistical differences were tested using the General Linear Method and paired t tests (p £.05), The extension of the knee starts both barefoot and shod significantly earlier than the resupination phase. Individual analysis shows that a larger time discrepancy between knee extension and the end of pronation mainly depends on the presence of bimodal pronation curves. The relative time differences significantly diminish with increased running velocity. Results suggest that by using this alternative approach, more detailed and useful information is available to describe the lime relationship between flexion-extension of the knee and pro-supination.

A Perturbation Study of Lower Extremity Motion during Running

1992 ◽  
Vol 8 (1) ◽  
pp. 30-47 ◽  
Author(s):  
Wilbert Van Woensel ◽  
Peter R. Cavanagh
Keyword(s):  
Lower Extremity ◽  
Knee Flexion ◽  
Sagittal Plane ◽  
Treadmill Running ◽  
Two Phase ◽  
Shoe Condition ◽  
Phase Profile ◽  
Flexion Extension ◽  
Extremity Motion ◽  
Rearfoot Motion

The present study explored kinematic adaptation in the lower extremity to running in shoes with 10° valgus and varus midsole perturbations. Rearfoot motion and knee flexion/extension data on nine subjects were collected using a Selspot II system during treadmill running in the two test shoes and in a neutral shoe condition. Maximum pronation was significantly altered by an amount approximately the same as the shoe perturbation, but there was no substantial adaptation in the amount of knee flexion. From the rearfoot patterns it was inferred that time to maximum pronation may be an unreliable variable to describe the pattern of rearfoot motion; the two-phase profile using rearfoot velocity may be more useful. It was concluded that certain subtle sagittal plane kinematic adaptations in timing and velocity patterns did occur at the knee in response to the shoe perturbations.

scholarly journals Gender Differences in Lower Extremity Coupling Variability during an Unanticipated Cutting Maneuver

2005 ◽  
Vol 21 (2) ◽  
pp. 143-152 ◽  
Author(s):  
Christine D. Pollard ◽  
Bryan C. Heiderscheit ◽  
Richard E.A. van Emmerik ◽  
Joseph Hamill
Keyword(s):  
Gender Differences ◽  
Lower Extremity ◽  
Ligament Injury ◽  
Coordination Pattern ◽  
Vector Coding ◽  
Flexible System ◽  
Environmental Perturbations ◽  
Flexion Extension ◽  
M 12 ◽  
Coordination Patterns

The purpose of this study was to determine if gender differences exist in the variability of various lower extremity (LE) segment and joint couplings during an unanticipated cutting maneuver. 3-D kinematics were collected on 24 college soccer players (12 M, 12 F) while each performed the cutting maneuver. The following intralimb couplings were studied: thigh rotation (rot)/leg rot; thigh abduction-adduction/leg abd-add; hip abd-add/knee rot; hip rot/knee abd-add; knee flexion-extension/knee rot; knee flx-ext/hip rot. A vector-coding technique applied to angle-angle plots was used to quantify the coordination of each coupling. The average between-trial standard deviation of the coordination pattern during the initial 40% of stance was used to indicate the coordination variability. One-tailed t-tests were used to determine differences between genders in coordination variability for each coupling. Women had decreased variability in four couplings: 32% less thigh rot/leg rot variability; 40% less thigh abd-add/leg abd-add variability; 46% less knee flx-ext/knee rot variability; and 44% less knee flx-ext/hip rot variability. These gender differences in LE coordination variability may be associated with the increased incidence of ACL injury in women. If women exhibit less flexible coordination patterns during competition, they may be less able to adapt to the environmental perturbations experienced during sports. These perturbations applied to a less flexible system may result in ligament injury.

scholarly journals Estimation of Kinematics from Inertial Measurement Units Using a Combined Deep Learning and Optimization Framework

2020 ◽  
Author(s):  
Eric Rapp ◽  
Soyong Shin ◽  
Wolf Thomsen ◽  
Reed Ferber ◽  
Eni Halilaj
Keyword(s):  
Neural Networks ◽  
Deep Learning ◽  
Lower Extremity ◽  
Deep Neural Networks ◽  
Measurement Unit ◽  
Large Set ◽  
Inertial Measurement Units ◽  
Inertial Measurement ◽  
Flexion Extension ◽  
Measurement Units

AbstractThe difficulty of estimating joint kinematics remains a critical barrier toward widespread use of inertial measurement units in biomechanics. Traditional sensor-fusion filters are largely reliant on magnetometer readings, which may be disturbed in uncontrolled environments. Careful sensor-to-segment alignment and calibration strategies are also necessary, which may burden users and lead to further error in uncontrolled settings. We introduce a new framework that combines deep learning and top-down optimization to accurately predict lower extremity joint angles directly from inertial data, without relying on magnetometer readings. We trained deep neural networks on a large set of synthetic inertial data derived from a clinical marker-based motion-tracking database of hundreds of subjects. We used data augmentation techniques and an automated calibration approach to reduce error due to variability in sensor placement and limb alignment. On left-out subjects, lower extremity kinematics could be predicted with a mean (± STD) root mean squared error of less than 1.27 ° (± 0.38 °) in flexion/extension, less than 2.52 ° (± 0.98 °) in ad/abduction, and less than 3.34 ° (± 1.02 °) internal/external rotation, across walking and running trials. Errors decreased exponentially with the amount of training data, confirming the need for large datasets when training deep neural networks. While this framework remains to be validated with true inertial measurement unit (IMU) data, the results presented here are a promising advance toward convenient estimation of gait kinematics in natural environments. Progress in this direction could enable large-scale studies and offer an unprecedented view into disease progression, patient recovery, and sports biomechanics.

scholarly journals Reliability and concurrent validity of Iphone®level application for measuring lower limb active flexion and extension range of motions in physical education students

2021 ◽  
Vol 25 (3) ◽  
pp. 164-171
Author(s):  
Izzet Kırkaya ◽  
Celil Kaçoğlu ◽  
Beyza Şenol
Keyword(s):  
Lower Extremity ◽  
Range Of Motion ◽  
Correlation Coefficient ◽  
Intraclass Correlation ◽  
Joint Range Of Motion ◽  
Active Flexion ◽  
Pearson Coefficient ◽  
Flexion Extension ◽  
Joint Range ◽  
Flexion And Extension

Background and Study Aim. The aim of this study was to analyse reliability and validity of accelerometer-based Iphone® Level application for measuring lower extremity active flexion and extension joint range of motion. Material and Methods. Thirty physically healthy students enrolled in sport sciences (11 males, 19 females, 21.2±1.5 years, Body mass 64.4±10.0 kg, Height 1.68±0.8 m, Fat percentage 21.2±7.8 %, 22.5±2.6 kg/m2) participated in the measurements of hip, knee, and ankle joint range of motion twice through Universal goniometer and Iphone® Level applications. The same experienced measurer carried out blind study of plantarflexion, dorsiflexion and knee flexion/extension, hip flexion/extension joint range of motion three times for each measurement methods and the other researcher recorded the results. For simultaneous validity analysis Pearson coefficient of correlation was used to decide the level of adaptation between the two intraclass correlation coefficient and Cronbach’s alpha values. Bland-Altman graphics were utilized for level of agreement between these two different methods. Results. The results of Pearson coefficient of correlation analysis revealed a positive correlation between the measurement values of joint range of motion performed through Universal goniometer and Level App (r2 = 0.44-0.94, p <0.05). Bland-Altman graphics showed a good agreement among Cronbach Alpha values and intraclass correlation coefficient in the confidence range of %95, and universal goniometers and Level App application. Conclusions. The results of this study revealed that goniometric measurements using Iphone® Level App is a good reliable method for measuring lower extremity active range of motion compared to universal goniometer.

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