Rotation Of Foot Research Articles

Mental rotation of feet in individuals with Body Integrity Identity Disorder, lower-limb amputees, and normally-limbed controls.

Body Integrity Identity Disorder (BIID) is a non-psychotic condition wherein individuals desire amputation or paralysis of one or more healthy, fully-functioning limbs (predominantly the legs). Individuals with BIID have been suggested to have a mismatch between the perceived mental representation of the body and its actual physical structure, such that their desired identity matches that of a lower-limb amputee. Accordingly, studies have reported an altered central network involving body representation of the legs in BIID, but its relationship to behavior remains unclear. In the present study, we investigated the integrity of body representation in individuals with BIID, acquired lower-limb amputees, and normally-limbed controls using an online mental rotation task. Participants judged the laterality of left and right foot images presented from different views, orientations, and of different types. We expected BIID participants to be slower for mentally rotating images that corresponded to their affected legs than lower-limb amputees and normally-limbed participants. We found that the groups did not significantly differ in their performance. All participants were slower at judging feet presented in awkward postures than natural postures, replicating previous studies and validating our online paradigm. The results are discussed in terms of the robust nature of visual and sensorimotor lower-limb representations, whether related to the self or as prototype, in the context of disturbed lower-limb integrity.

Nonlinear Rotation of Capacity-Protected Foundations: The 2015 Canadian Building Code

When foundations are capacity-protected, inelastic deformations will occur primarily in the seismic force-resisting system. Soil flexibility can be ignored when determining seismic loads, but footings will rotate when subjected to the maximum overturning moment, and this may increase building drifts, particularly in lower stories where gravity-load columns are less flexible. A “hand calculation” method is presented for estimating rotation of a footing from the uniform bearing stress distribution required to resist the applied overturning moment. The method, which has been adopted in the 2015 Canadian building code, accounts for initial linear rotation of footings and additional nonlinear rotation due to footing uplift and nonlinearity of soil. A quick, safe estimate can be made using approximate equations, or a more accurate estimate can be made by determining two parameters from figures. Design examples demonstrate how the method can be used to design foundations for improved performance at a small additional cost.

Efficiency improvement of walking assist machine using crutches based on gait-feasible region analysis

To improve gait efficiency of a walking assist machine using crutches (WAMC), a parameter study has been carried out to introduce the gait-feasible region (GFR). GFR is the region of a set of state variables of WAMC in which safe gait can be achieved. Evaluation indices for energy consumption and ride comfort are derived. On the basis of these indices with GFR, design of suitable control input parameter to achieve efficient and comfortable gait is discussed. A foot-driving mechanism (FDM), which amplifies the actuator input to generate quick rotation of foot without an additional actuator, is introduced to improve energy consumption and ride comfort of WAMC, and its simple and practical composition is presented. On the basis of the results of several simulations and experiments using a prototype, validity and effectiveness of the proposed methodology are demonstrated.

The Effect of the Toe on the Biped Robot

Evaluation of 9-DOF biped robots based on designated smooth and stable trajectories with two added toes is a challenging problem that is the focus of this paper. Simultaneously rotation of feet and toes is considered, which allows the robot to walk more efficiently and like a human being. A desired trajectory for the lower body is designed to increase the stability margin. This obtained by fitting proper polynomials at appropriate break points. Then, the upper body motion is planned based on the Zero Moment Point (ZMP) criterion to provide a stable motion for the biped robot. Next, dynamics equations are obtained for both single support phase (SSP) and double support phase (DSP). On the other hand, two biped robots, which one accompanied by toes, are also compared. Simulation results reveal that the biped robots with toes have better stability margin, less power consumption and more vertical reaction force.

GA Based Trajectory Generation for a 7-DOF Biped Robot by Considering Feet Rotation during Double Support Phase

This paper presents a trajectory generation approach for a 7-DOF biped robot on level ground. Simultaneously rotation of feet in double support phase is considered which leads to high-speed and more similar to human being walking. The zero moment point (ZMP) stability criterion is used to ensure the stability of the bipedal walking robot. Since ZMP trajectory in human walking does not stay fixed, it needs to be a straight line shaped forward ZMP trajectory to have a natural walk. A genetic algorithm based method is proposed to obtain key parameters in trajectory generation such that the ZMP follows a predefined trajectory while minimizing power consumption. Simulation results demonstrate the effectiveness of the proposed method.

Gait training with partial body weight support during overground walking for individuals with chronic stroke: a pilot study

BackgroundIt is not yet established if the use of body weight support (BWS) systems for gait training is effective per se or if it is the combination of BWS and treadmill that improves the locomotion of individuals with gait impairment. This study investigated the effects of gait training on ground level with partial BWS in individuals with stroke during overground walking with no BWS.MethodsTwelve individuals with chronic stroke (53.17 ± 7.52 years old) participated of a gait training program with BWS during overground walking, and were evaluated before and after the gait training period. In both evaluations, individuals were videotaped walking at a self-selected comfortable speed with no BWS. Measurements were obtained for mean walking speed, step length, stride length and speed, toe-clearance, durations of total double stance and single-limb support, and minimum and maximum foot, shank, thigh, and trunk segmental angles.ResultsAfter gait training, individuals walked faster, with symmetrical steps, longer and faster strides, and increased toe-clearance. Also, they displayed increased rotation of foot, shank, thigh, and trunk segmental angles on both sides of the body. However, the duration of single-limb support remained asymmetrical between each side of the body after gait training.ConclusionsGait training individuals with chronic stroke with BWS during overground walking improved walking in terms of temporal-spatial parameters and segmental angles. This training strategy might be adopted as a safe, specific and promising strategy for gait rehabilitation after stroke.

Effects of lower limb amputation on the mental rotation of feet.

What happens to the mental representation of our body when the actual anatomy of our body changes? We asked 18 able-bodied controls, 18 patients with a lower limb amputation and a patient with rotationplasty to perform a laterality judgment task. They were shown illustrations of feet in different orientations which they had to classify as left or right limb. This laterality recognition task, originally introduced by Parsons in Cognit Psychol 19:178–241, (1987), is known to elicit implicit mental rotation of the subject’s own body part. However, it can also be solved by mental transformation of the visual stimuli. Despite the anatomical changes in the body periphery of the amputees and of the rotationplasty patient, no differences in their ability to identify illustrations of their affected versus contralateral limb were found, while the group of able-bodied controls showed clear laterality effects. These findings are discussed in the context of various strategies for mental rotation versus the maintenance of an intact prototypical body structural description.

Lethal cutis laxa with contractural arachnodactyly, overgrowth and soft tissue bleeding due to a novel homozygous fibulin‐4 gene mutation

Cutis laxa is characterised by redundant, inelastic skin with deep wrinkling and additional variable systemic involvement. Mutations in fibulin-4 (EFEMP2) and fibulin-5 (FBLN5) were described to be causative for autosomal recessive cutis laxa type 1 in a few families each. The female patient was born to healthy consanguineous parents. Pregnancy was remarkable for fetal overgrowth and oligohydramnios. The newborn girl showed extreme bradycardia and died perinatally. Apart from overgrowth, cutis laxa, arachnodactyly of hands and feet with contractures of the third to fifth finger, medial rotation of feet, spina bifida of the os sacrum, microcephaly and facial dysmorphism were noted. Autopsy showed collapsed lungs with hypoplastic diaphragm and signs of cervical soft tissue bleedings due to fragility of vessels. Histologic examination showed fragmentation of elastic fibres with formation of cystic cavities in the medial layer of the aorta and central lung vessels. Sequencing of the elastin, fibulin-4 and fibulin-5 genes revealed a homozygous missense mutation (p.Cys267Tyr) in the fibulin-4 gene in the patient. Our observation increases the number of cases with fibulin-4 mutations to three and extends the phenotypic spectrum of fibulin-4 mutations by microcephaly, overgrowth and arachnodactyly.

Comparison of different gaits with rotation of the feet for a planar biped

Fast human walking includes a phase where the stance heel rises from the ground and the stance foot rotates about the stance toe. This phase where the biped becomes under-actuated is not present during the walk of humanoid robots. The objective of this study is to determine if this phase is useful to reduce the energy consumed in the walking. In order to study the efficiency of this phase, six cyclic gaits are presented for a planar biped robot. The simplest cyclic motion is composed of successive single support phases with flat stance foot on the ground. The most complex cyclic motion is composed of single support phases that include a sub-phase of rotation of the stance foot about the toe and of finite time double support phase. For the synthesis of these walking gaits, optimal motions with respect to the torque cost, are defined by taking into account given performances of actuators. It is shown that for fast motions a foot rotation sub-phase is useful to reduce the criteria cost. In the optimization process, under-actuated phase (foot rotation phase), fully-actuated phase (flat foot phase) and over-actuated phase (double support phase) are considered.

A new ichnotaxon of fossil bird track from the Early Cretaceous Tianjialou Formation (Barremian-Albian), Shandong Province, China

A single set of 5 bird tracks was discovered in the Tianjialou Formation (Barremian-Albian) of Junan County, Shandong Province, China. After careful study we infer that it is a new type of bird tracks, and a new ichnogenus was erected and the name Shandongornipes was given. The characteristics of the new bird track are as follows: Moderately large tetradactyl footprints with well-developed hallux impression. Track width (about 5.8 cm) almost equal to track length (excluding hallux); total length of track (including hallux) 8.7 cm. The digit impressions are slender, with distal ends showing long sharp claw marks. Hallux posteriorly-directed, and hallux impressions well-developed. Digits II, III and IV point anteriorly, exhibiting mesaxonic asymmetry: divarication angle between II and III much larger than that of III and IV, the former ranging from 91° to 118°, and the latter less than 30°. Divarication between digits II and IV ranging from 128° to 142°. Without web structures. Digital pads recognizable, usually at least three in digits III and IV, but sometimes only two due to preservation. The trackway shows slight positive (inward) rotation of feet. The bird tracks occur in association with abundant dinosaur tracks, and are believed to have formed in flood plain environments.

Maisonneuve fracture in an adolescent

We present an atypical case with a rare combination of Maisonneuve and triplane fracture A Maisonneuve injury can present with external rotation of foot in the absence of signs and symptoms of a proximal injury. Pre-operative CT scans of the growth plate injury facilitates planning open reduction and internal fixation; it is vital to check the syndesmotic stability by intra-operative imaging. This rare combination of fracture pattern illustrates the need for awareness of the dual pathology and to provide adequate stability to prevent chronic ankle pain.

Quantitative analysis of gai pattern in hemiparetic patients

To characterise gait pattern in hemiparetic patients quantitatively using clinical footprint method. A case control study. Sixteen hemiparetic patients (12 males and 4 females) aged 16 to 64 years who attended neurological clinic at Queen Elizabeth Central Hospital, Blantyre, Malawi. Stride length, step width, foot rotation angle measured using footprint method. The difference in mean values of the three variables of gait between affected and unaffected sides in hemiparetic patients was not significant. However, strides were significantly longer in controls than in patients (P<0.001) while patients had significantly broader steps (P<0.02). In the controls, foot was rotated externally in 87.7% of steps and internally in 14.3% of steps. In the hemiparetic patients, intoeing pattern was observed in 41.3% of steps. The difference in variability of stride length and foot angle between affected and non-affected sides of patients was not significant. Stride-to-stride variability in stride length in patients was 1.6 times higher than in controls. Variability of step width and foot progression angle was 1.4 and 1.6 times higher in patients than in controls. Footprint method provides fast and inexpensive tool for clinical gait analysis and is suitable for evaluation of hemiparetic patients. Our findings suggest that areas of emphasis for physical therapy of hemiparetic patients should include increasing stride length and decreasing step width and internal rotation of foot, particularly on the affected side.

Settlement and rotation of footings embedded in sand. Technical note: Georgiadis, M Soils FoundV33, N1, March 1993, P169–175

Settlement and rotation of footings embedded in sand. Technical note: Georgiadis, M Soils FoundV33, N1, March 1993, P169–175

Settlement and Rotation of Footings Embedded in Sand

A series of model tests has been conducted to study the effect of footing embedment and load eccentricity on the load-settlement and moment-rotation relationships as well as on the bearing capacity. A method was developed for predicting the nonlinear response of an embedded footing, which uses elasticity theory to model soil behavior at low load levels and then incorporates soil nonlinearity in compliance with the experimental behavior. In addition, the effect of embedment on the interaction diagrams between vertical loads and moments that cause failure of the footing is analyzed.

Rotation of footings due to surface waves

abstract A possible failure mode for a column is presented. Surface waves could cause a spread footing to rotate failing the column at its base.