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Sample records for plantar flexion torque

  1. Measurement of Resistive Plantar Flexion Torque of the Ankle during Passive Stretch in Healthy Subjects and Patients with Poststroke Hemiplegia.

    PubMed

    Mizuno, Shiho; Sonoda, Shigeru; Takeda, Kotaro; Maeshima, Shinichiro

    2016-04-01

    Quantification of increased muscle tone for patients with spasticity has been performed to date using various devices to replace the manual scales, such as the modified Ashworth scale or the Tardieu scale. We developed a device that could measure resistive plantar flexion (PF) torque of the ankle during passive dorsiflexion (DF) as an indicator of muscle tone of ankle plantar flexors. The primary objective was to explore the test-retest intrarater reliability of a custom-built device. Participants were 11 healthy subjects (7 men, 4 women; mean age 47.0 years) and 22 patients with poststroke hemiplegia (11 hemorrhagic, 11 ischemic; 14 men, 8 women; mean age 57.2 years). The device was affixed to the ankle. Subjects were seated with knees either flexed or extended. The ankle was passively dorsiflexed from 20° of PF to more than 10° of DF at 5°/second (slow stretch) or 90°/second (fast stretch). Angle and torque were measured twice during the stretches. The intraclass correlation coefficients (ICCs) of torque at 10° of DF (T10) in the 4 conditions-slow and fast stretches with knee flexed or extended-were calculated. The T10 ICCs of the 4 conditions were .95-.99 in both groups. The healthy subjects showed significantly higher T10 of knee extension than of knee flexion during slow and fast stretches. The patients showed increased velocity-dependent torque during fast stretches. Excellent reliability was observed. The device is suitable for measuring resistive PF torque during passive stretch in a flexed knee condition. Copyright © 2016 National Stroke Association. Published by Elsevier Inc. All rights reserved.

  2. Output of skeletal muscle contractions. a study of isokinetic plantar flexion in athletes.

    PubMed

    Fugl-Meyer, A R; Mild, K H; Hörnsten, J

    1982-06-01

    Maximum torques, total work and mean power of isokinetic plantar flexions were measured with simultaneous registrations. The integrated electromyograms (iEMG) were obtained by surface electrodes from all three heads of the m. triceps surae. The method applied offers possibilities for adequate description of dynamic muscular work which in the case of plantar flexion in trained man declines as a negative exponential function of angular motion velocity. The decline is parallel to that of maximum torques. The summed triceps surae iEMG was inversely proportional to the velocity and direct proportional to time suggesting that structural rather than neural factors determine the relationships between velocity of angular motion and maximum torque/total work of single Mmaneuvers. Moreover, the fact that maximum mean power as well as maximum electrical efficiency were reached at the functional velocity of toe-off during gait suggests an influence of pragmatic demands on plantar flexion mechanical output.

  3. Plantar flexion force induced by amplitude-modulated tendon vibration and associated soleus V/F-waves as an evidence of a centrally-mediated mechanism contributing to extra torque generation in humans

    PubMed Central

    2013-01-01

    Background High-frequency trains of electrical stimulation applied over the human muscles can generate forces higher than would be expected by direct activation of motor axons, as evidenced by an unexpected relation between the stimuli and the evoked contractions, originating what has been called “extra forces”. This phenomenon has been thought to reflect nonlinear input/output neural properties such as plateau potential activation in motoneurons. However, more recent evidence has indicated that extra forces generated during electrical stimulation are mediated primarily, if not exclusively, by an intrinsic muscle property, and not from a central mechanism as previously thought. Given the inherent differences between electrical and vibratory stimuli, this study aimed to investigate: (a) whether the generation of vibration-induced muscle forces results in an unexpected relation between the stimuli and the evoked contractions (i.e. extra forces generation) and (b) whether these extra forces are accompanied by signs of a centrally-mediated mechanism or whether intrinsic muscle properties are the predominant mechanisms. Methods Six subjects had their Achilles tendon stimulated by 100 Hz vibratory stimuli that linearly increased in amplitude (with a peak-to-peak displacement varying from 0 to 5 mm) for 10 seconds and then linearly decreased to zero for the next 10 seconds. As a measure of motoneuron excitability taken at different times during the vibratory stimulation, short-latency compound muscle action potentials (V/F-waves) were recorded in the soleus muscle in response to supramaximal nerve stimulation. Results Plantar flexion torque and soleus V/F-wave amplitudes were increased in the second half of the stimulation in comparison with the first half. Conclusion The present findings provide evidence that vibratory stimuli may trigger a centrally-mediated mechanism that contributes to the generation of extra torques. The vibration-induced increased motoneuron

  4. Effects of 4 Weeks of Explosive-type Strength Training for the Plantar Flexors on the Rate of Torque Development and Postural Stability in Elderly Individuals.

    PubMed

    Kobayashi, Y; Ueyasu, Y; Yamashita, Y; Akagi, R

    2016-06-01

    This study aimed to investigate the effect of a 4-week explosive-type strength training program for the plantar flexors on the rate of torque development and postural stability. The participants were 56 elderly men and women divided into training (17 men and 15 women) and control (14 men and 10 women) groups. The participants in the training group underwent explosive-type strength training of the plantar flexors 2 days per week for 4 weeks. Training consisted of 3 sets of 10 repetitions of explosive plantar flexion lasting less than 1 s. The following parameters were determined: muscle volume of the plantar flexors estimated by the muscle thickness and lower leg length, maximal voluntary contraction torque and rate of torque development of plantar flexion, and one-leg standing ability. The training increased the maximal voluntary contraction torque and rate of torque development, but corresponding increases in muscle volume and one-leg standing ability were not found. These results suggest that, for elderly individuals, the 4-week explosive-type strength training of the plantar flexors is effective for increasing the maximal voluntary contraction torque and rate of torque development of plantar flexion but is not effective for improving postural stability. © Georg Thieme Verlag KG Stuttgart · New York.

  5. The influence of aging on the isometric torque sharing patterns among the plantar flexor muscles.

    PubMed

    Oliveira, Liliam F; Verneque, Debora; Menegaldo, Luciano L

    2017-01-01

    Physiological cross-sectional area (PCSA) reduction of the triceps surae (TS) muscles during aging suggests a proportional loss of torque among its components: soleus, medial and lateral gastrocnemii. However, direct measurements of muscle forces in vivo are not feasible. The purpose of this paper was to compare, between older and young women, isometric ankle joint torque sharing patterns among TS muscles and tibialis anterior (TA). An EMG-driven model was used for estimating individual muscle torque contributions to the total plantar flexor torque, during sustained contractions of 10% and 40% of maximum voluntary contraction (MVC). Relative individual muscle contributions to the total plantar flexion torque were similar between older and young women groups, for both intensities, increasing from LG, MG to SOL. Muscle strength (muscle torque/body mass) was significantly greater for all TS components in 40% MVC contractions. Increased TA activation was observed in 10% of MVC for older people. Despite the reduced maximum isometric torque and muscle strength, the results suggest small variations of ankle muscle synergies during the aging process.

  6. Relative sensitivity of depth discrimination for ankle inversion and plantar flexion movements.

    PubMed

    Black, Georgia; Waddington, Gordon; Adams, Roger

    2014-02-01

    25 participants (20 women, 5 men) were tested for sensitivity in discrimination between sets of six movements centered on 8 degrees, 11 degrees, and 14 degrees, and separated by 0.3 degrees. Both inversion and plantar flexion movements were tested. Discrimination of the extent of inversion movement was observed to decline linearly with increasing depth; however, for plantar flexion, the discrimination function for movement extent was found to be non-linear. The relatively better discrimination of plantar flexion movements than inversion movements at around 11 degrees from horizontal is interpreted as an effect arising from differential amounts of practice through use, because this position is associated with the plantar flexion movement made in normal walking. The fact that plantar flexion movements are discriminated better than inversion at one region but not others argues against accounts of superior proprioceptive sensitivity for plantar flexion compared to inversion that are based on general properties of plantar flexion such as the number of muscle fibres on stretch.

  7. Plantar-flexion of the ankle joint complex in terminal stance is initiated by subtalar plantar-flexion: A bi-planar fluoroscopy study.

    PubMed

    Koo, Seungbum; Lee, Kyoung Min; Cha, Young Joo

    2015-10-01

    Gross motion of the ankle joint complex (AJC) is a summation of the ankle and subtalar joints. Although AJC kinematics have been widely used to evaluate the function of the AJC, the coordinated movements of the ankle and subtalar joints are not well understood. The purpose of this study was to accurately quantify the individual kinematics of the ankle and subtalar joints in the intact foot during ground walking by using a bi-planar fluoroscopic system. Bi-planar fluoroscopic images of the foot and ankle during walking and standing were acquired from 10 healthy subjects. The three-dimensional movements of the tibia, talus, and calcaneus were calculated with a three-dimensional/two-dimensional registration method. The skeletal kinematics were quantified from 9% to 86% of the full stance phase because of the limited camera speed of the X-ray system. At the beginning of terminal stance, plantar-flexion of the AJC was initiated in the subtalar joint on average at 75% ranging from 62% to 76% of the stance phase, and plantar-flexion of the ankle joint did not start until 86% of the stance phase. The earlier change to plantar-flexion in the AJC than the ankle joint due to the early plantar-flexion in the subtalar joint was observed in 8 of the 10 subjects. This phenomenon could be explained by the absence of direct muscle insertion on the talus. Preceding subtalar plantar-flexion could contribute to efficient and stable ankle plantar-flexion by locking the midtarsal joint, but this explanation needs further investigation. Copyright © 2015 Elsevier B.V. All rights reserved.

  8. Activation of plantar flexor muscles is constrained by multiple muscle synergies rather than joint torques

    PubMed Central

    Suzuki, Takahito; Kinugasa, Ryuta; Fukashiro, Senshi

    2017-01-01

    Behavioral evidence has suggested that a small number of muscle synergies may be responsible for activating a variety of muscles. Nevertheless, such dimensionality reduction may also be explained using the perspective of alternative hypotheses, such as predictions based on linear combinations of joint torques multiplied by corresponding coefficients. To compare the explanatory capacity of these hypotheses for describing muscle activation, we enrolled 12 male volunteers who performed isometric plantar flexor contractions at 10–100% of maximum effort. During each plantar flexor contraction, the knee extensor muscles were isometrically contracted at 0%, 50%, or 100% of maximum effort. Electromyographic activity was recorded from the vastus lateralis, medial gastrocnemius (MG), lateral gastrocnemius (LG), and soleus muscles and quantified using the average rectified value (ARV). At lower plantar flexion torque, regression analysis identified a clear linear relationship between the MG and soleus ARVs and between the MG and LG ARVs, suggesting the presence of muscle synergy (r2 > 0.65). The contraction of the knee extensor muscles induced a significant change in the slope of this relationship for both pairs of muscles (MG × soleus, P = 0.002; MG × LG, P = 0.006). Similarly, the slope of the linear relationship between the plantar flexion torque and the ARV of the MG or soleus changed significantly with knee extensor contraction (P = 0.031 and P = 0.041, respectively). These results suggest that muscle synergies characterized by non-mechanical constraints are selectively recruited according to whether contraction of the knee extensor muscles is performed simultaneously, which is relatively consistent with the muscle synergy hypothesis. PMID:29107958

  9. Anterior fibrous bundle: a cause of residual pain and restrictive plantar flexion following ankle sprain.

    PubMed

    Miyamoto, Wataru; Takao, Masato; Matsushita, Takashi

    2013-06-01

    To describe anterior fibrous bundle as an intra-articular residual disorder following ankle sprain. Between January 1998 and January 2009, we performed arthroscopy on 10 patients (7 males, 3 females; median age, 25 years; age range, 17-43 years) who had the uncommon problem of anterior ankle pain accompanied by restriction of plantar flexion following an ankle sprain. Pre-operative magnetic resonance imaging revealed osteochondral lesions (OCLs) of the talar dome in 3 patients, but no other findings that could explain restricted plantar flexion. All patients underwent arthroscopy for investigation and treatment of the cause of symptoms, and the 3 patients with OCL underwent additional arthroscopic drilling. Outcome was measured using the American Orthopedic Foot and Ankle Society Ankle-Hindfoot Scale (AOFAS) score, Visual Analogue Scale (VAS) for pain and active plantar flexion angle. In all patients, an anterior fibrous bundle was confirmed under arthroscopic investigation as the cause of symptoms and was resected arthroscopically. Median AOFAS and VAS scores improved significantly from 65 (range 61-82) and 70 (range 50-85) pre-operatively to 95 (range 84-100) and 4 (range 0-15) at final follow-up, respectively (p < 0.001). In addition, median active plantar flexion angle improved significantly from 40° (range 35-40) pre-operatively to 55° (range 45-55), (p < 0.01). An anterior fibrous bundle is one of the intra-articular residual disorders after ankle sprain that can cause restriction of plantar flexion.

  10. Plantar-flexor Static Stretch Training Effect on Eccentric and Concentric Peak Torque – A comparative Study of Trained versus Untrained Subjects

    PubMed Central

    Abdel-aziem, Amr Almaz; Mohammad, Walaa Sayed

    2012-01-01

    The aim of this study was to examine the long-term effects of static stretching of the plantar-flexor muscles on eccentric and concentric torque and ankle dorsiflexion range of motion in healthy subjects. Seventy five healthy male volunteers, with no previous history of trauma to the calf that required surgery, absence of knee flexion contracture and no history of neurologic dysfunction or disease, systemic disease affecting the lower extremities were selected for this study. The participants were divided into three equal groups. The control group did not stretch the plantar-flexor muscles. Two Experimental groups (trained and untrained) were instructed to perform static stretching exercise of 30 second duration and 5 repetitions twice daily. The stretching sessions were carried out 5 days a week for 6 weeks. The dorsiflexion range of motion was measured in all subjects. Also measured was the eccentric and concentric torque of plantar-flexors at angular velocities of 30 and 120°/s pre and post stretching. Analysis of variance showed a significant increase in plantar-flexor eccentric and concentric torque (p < 0.05) of trained and untrained groups, and an increase in dorsiflexion range of motion (p < 0.05) at both angular velocities for the untrained group only. The static stretching program of plantar-flexors was effective in increasing the concentric and eccentric plantarflexion torque at angular velocities of 30 and 120°/s. Increases in plantar-flexors flexibility were observed in untrained subjects. PMID:23486840

  11. Blood pressure and calf muscle oxygen extraction during plantar flexion exercise in peripheral artery disease.

    PubMed

    Luck, J Carter; Miller, Amanda J; Aziz, Faisal; Radtka, John F; Proctor, David N; Leuenberger, Urs A; Sinoway, Lawrence I; Muller, Matthew D

    2017-07-01

    Peripheral artery disease (PAD) is an atherosclerotic vascular disease that affects 200 million people worldwide. Although PAD primarily affects large arteries, it is also associated with microvascular dysfunction, an exaggerated blood pressure (BP) response to exercise, and high cardiovascular mortality. We hypothesized that fatiguing plantar flexion exercise that evokes claudication elicits a greater reduction in skeletal muscle oxygenation (SmO 2 ) and a higher rise in BP in PAD compared with age-matched healthy subjects, but low-intensity steady-state plantar flexion elicits similar responses between groups. In the first experiment, eight patients with PAD and eight healthy controls performed fatiguing plantar flexion exercise (from 0.5 to 7 kg for up to 14 min). In the second experiment, seven patients with PAD and seven healthy controls performed low-intensity plantar flexion exercise (2.0 kg for 14 min). BP, heart rate (HR), and SmO 2 were measured continuously using near-infrared spectroscopy (NIRS). SmO 2 is the ratio of oxygenated hemoglobin to total hemoglobin, expressed as a percent. At fatigue, patients with PAD had a greater increase in mean arterial BP (18 ± 2 vs. vs. 10 ± 2 mmHg, P = 0.029) and HR (14 ± 2 vs. 6 ± 2 beats/min, P = 0.033) and a greater reduction in SmO 2 (-54 ± 10 vs. -12 ± 4%, P = 0.001). However, both groups had similar physiological responses to low-intensity, nonpainful plantar flexion exercise. These data suggest that patients with PAD have altered oxygen uptake and/or utilization during fatiguing exercise coincident with an augmented BP response. NEW & NOTEWORTHY In this laboratory study, patients with peripheral artery disease performed plantar flexion exercise in the supine posture until symptoms of claudication occurred. Relative to age- and sex-matched healthy subjects we found that patients had a higher blood pressure response, a higher heart rate response, and a greater reduction in skeletal muscle oxygenation as

  12. Isometric hip-rotator torque production at varying degrees of hip flexion.

    PubMed

    Johnson, Sam; Hoffman, Mark

    2010-02-01

    Hip torque production is associated with certain knee injuries. The hip rotators change function depending on hip angle. To compare hip-rotator torque production between 3 angles of hip flexion, limbs, and sexes. Descriptive. University sports medicine research laboratory. 15 men and 15 women, 19-39 y. Three 6-s maximal isometric contractions of the hip external and internal rotators at 10 degrees, 40 degrees, and 90 degrees of hip flexion on both legs. Average torque normalized to body mass. Internal-rotation torque was greatest at 90 degrees of hip flexion, followed by 40 degrees of hip flexion and finally 10 degrees of hip flexion. External-rotation torque was not different based on hip flexion. The nondominant leg's external rotators were stronger than the dominant leg's, but the reverse was true for internal rotators. Finally, the men had more overall rotator torque. Hip-rotation torque production varies between flexion angle, leg, and sex. Clinicians treating lower extremity problems need to be aware of these differences.

  13. Variation in the location of the shoe sole flexion point influences plantar loading patterns during gait

    PubMed Central

    2014-01-01

    Background Several footwear design characteristics are known to have detrimental effects on the foot. However, one characteristic that has received relatively little attention is the point where the sole flexes in the sagittal plane. Several footwear assessment forms assume that this should ideally be located directly under the metarsophalangeal joints (MTPJs), but this has not been directly evaluated. The aim of this study was therefore to assess the influence on plantar loading of different locations of the shoe sole flexion point. Method Twenty-one asymptomatic females with normal foot posture participated. Standardised shoes were incised directly underneath the metatarsophalangeal joints, proximal to the MTPJs or underneath the midfoot. The participants walked in a randomised sequence of the three shoes whilst plantar loading patterns were obtained using the Pedar® in-shoe pressure measurement system. The foot was divided into nine anatomically important masks, and peak pressure (PP), contact time (CT) and pressure time integral (PTI) were determined. A ratio of PP and PTI between MTPJ2-3/MTPJ1 was also calculated. Results Wearing the shoe with the sole flexion point located proximal to the MTPJs resulted in increased PP under MTPJ 4–5 (6.2%) and decreased PP under the medial midfoot compared to the sub-MTPJ flexion point (−8.4%). Wearing the shoe with the sole flexion point located under the midfoot resulted in decreased PP, CT and PTI in the medial and lateral hindfoot (PP: −4.2% and −5.1%, CT: −3.4% and −6.6%, PTI: −6.9% and −5.7%) and medial midfoot (PP: −5.9% CT: −2.9% PTI: −12.2%) compared to the other two shoes. Conclusion The findings of this study indicate that the location of the sole flexion point of the shoe influences plantar loading patterns during gait. Specifically, shoes with a sole flexion point located under the midfoot significantly decrease the magnitude and duration of loading under the midfoot and hindfoot, which

  14. Hybrid diffuse optical techniques for continuous hemodynamic measurement in gastrocnemius during plantar flexion exercise

    NASA Astrophysics Data System (ADS)

    Henry, Brad; Zhao, Mingjun; Shang, Yu; Uhl, Timothy; Thomas, D. Travis; Xenos, Eleftherios S.; Saha, Sibu P.; Yu, Guoqiang

    2015-12-01

    Occlusion calibrations and gating techniques have been recently applied by our laboratory for continuous and absolute diffuse optical measurements of forearm muscle hemodynamics during handgrip exercises. The translation of these techniques from the forearm to the lower limb is the goal of this study as various diseases preferentially affect muscles in the lower extremity. This study adapted a hybrid near-infrared spectroscopy and diffuse correlation spectroscopy system with a gating algorithm to continuously quantify hemodynamic responses of medial gastrocnemius during plantar flexion exercises in 10 healthy subjects. The outcomes from optical measurement include oxy-, deoxy-, and total hemoglobin concentrations, blood oxygen saturation, and relative changes in blood flow (rBF) and oxygen consumption rate (rV˙O2). We calibrated rBF and rV˙O2 profiles with absolute baseline values of BF and V˙O2 obtained by venous and arterial occlusions, respectively. Results from this investigation were comparable to values from similar studies. Additionally, significant correlation was observed between resting local muscle BF measured by the optical technique and whole limb BF measured concurrently by a strain gauge venous plethysmography. The extensive hemodynamic and metabolic profiles during exercise will allow for future comparison studies to investigate the diagnostic value of hybrid technologies in muscles affected by disease.

  15. Volitional control of ankle plantar flexion in a powered transtibial prosthesis during stair-ambulation.

    PubMed

    Kannape, Oliver A; Herr, Hugh M

    2014-01-01

    Although great advances have been made in the design and control of lower extremity prostheses, walking on different terrains, such as ramps or stairs, and transitioning between these terrains remains a major challenge for the field. In order to generalize biomimetic behaviour of active lower-limb prostheses top-down volitional control is required but has until recently been deemed unfeasible due to the difficulties involved in acquiring an adequate electromyographic (EMG) signal. In this study, we hypothesize that a transtibial amputee can extend the functionality of a hybrid controller, designed for level ground walking, to stair ascent and descent by volitionally modulating powered plantar-flexion of the prosthesis. We here present data illustrating that the participant is able to reproduce ankle push-off behaviour of the intrinsic controller during stair ascent as well as prevent inadvertent push-off during stair descent. Our findings suggest that EMG signal from the residual limb muscles can be used to transition between level-ground walking and stair ascent/descent within a single step and significantly improve prosthesis performance during stair-ambulation.

  16. Change in the Mechanical Energy of the Body Center of Mass in Hemiplegic Gait after Continuous Use of a Plantar Flexion Resistive Ankle-foot Orthosis.

    PubMed

    Haruna, Hirokazu; Sugihara, Shunichi; Kon, Keisuke; Miyasaka, Tomoya; Hayakawa, Yasuyuki; Nosaka, Toshiya; Kimura, Kazuyuki

    2013-11-01

    [Purpose] The aim of this study was to investigate the changes in mechanical energy due to continuous use of a plantar flexion resistive ankle-foot orthosis (AFO) of subjects with chronic hemiplegia. [Subjects and Methods] The subjects were 5 hemiplegic patients using AFOs without a plantar flexion resistive function in their daily lives. We analyzed the gait of the subjects using a 3D motion capture system under three conditions: patients' use of their own AFOs; after being fitted with a plantar flexion resistive AFO; and after continuous use of the device. The gait efficiency was determined by calculating the mutual exchange of kinetic and potential energy of the center of mass. [Results] An increased exchange rate of the kinetic and potential energy was found for all subjects. A larger increase of energy exchange was shown on the non-paralyzed side, and after continuous use of the plantar flexion resistive AFO. [Conclusion] We found that continuous use of a plantar flexion resistive AFO increased the rate of mutual exchange between kinetic energy and potential energy. The change in the rate was closely related to the role of the non-paretic side, showing that the subjects needed a certain amount of time to adapt to the plantar flexion resistive AFO.

  17. Impact of age on exercise-induced ATP supply during supramaximal plantar flexion in humans

    PubMed Central

    Trinity, Joel D.; Hart, Corey R.; Kim, Seong-Eun; Groot, H. Jonathan; Fur, Yann Le; Sorensen, Jacob R.; Jeong, Eun-Kee; Richardson, Russell S.

    2015-01-01

    Currently, the physiological factors responsible for exercise intolerance and bioenergetic alterations with age are poorly understood due, at least in art, to the confounding effect of reduced physical activity in the elderly. Thus, in 40 healthy young (22 ± 2 yr) and old (74 ± 8 yr) activity-matched subjects, we assessed the impact of age on: 1) the relative contribution of the three major pathways of ATP synthesis (oxidative ATP synthesis, glycolysis, and the creatine kinase reaction) and 2) the ATP cost of contraction during high-intensity exercise. Specifically, during supramaximal plantar flexion (120% of maximal aerobic power), to stress the functional limits of the skeletal muscle energy systems, we used 31P-labeled magnetic resonance spectroscopy to assess metabolism. Although glycolytic activation was delayed in the old, ATP synthesis from the main energy pathways was not significantly different between groups. Similarly, the inferred peak rate of mitochondrial ATP synthesis was not significantly different between the young (25 ± 8 mM/min) and old (24 ± 6 mM/min). In contrast, the ATP cost of contraction was significantly elevated in the old compared with the young (5.1 ± 2.0 and 3.7 ± 1.7 mM·min−1·W−1, respectively; P < 0.05). Overall, these findings suggest that, when young and old subjects are activity matched, there is no evidence of age-related mitochondrial and glycolytic dysfunction. However, this study does confirm an abnormal elevation in exercise-induced skeletal muscle metabolic demand in the old that may contribute to the decline in exercise capacity with advancing age. PMID:26041112

  18. In vivo maximal fascicle-shortening velocity during plantar flexion in humans.

    PubMed

    Hauraix, Hugo; Nordez, Antoine; Guilhem, Gaël; Rabita, Giuseppe; Dorel, Sylvain

    2015-12-01

    Interindividual variability in performance of fast movements is commonly explained by a difference in maximal muscle-shortening velocity due to differences in the proportion of fast-twitch fibers. To provide a better understanding of the capacity to generate fast motion, this study aimed to 1) measure for the first time in vivo the maximal fascicle-shortening velocity of human muscle; 2) evaluate the relationship between angular velocity and fascicle-shortening velocity from low to maximal angular velocities; and 3) investigate the influence of musculo-articular features (moment arm, tendinous tissues stiffness, and muscle architecture) on maximal angular velocity. Ultrafast ultrasound images of the gastrocnemius medialis were obtained from 31 participants during maximal isokinetic and light-loaded plantar flexions. A strong linear relationship between fascicle-shortening velocity and angular velocity was reported for all subjects (mean R(2) = 0.97). The maximal shortening velocity (V(Fmax)) obtained during the no-load condition (NLc) ranged between 18.8 and 43.3 cm/s. V(Fmax) values were very close to those of the maximal shortening velocity (V(max)), which was extrapolated from the F-V curve (the Hill model). Angular velocity reached during the NLc was significantly correlated with this V(Fmax) (r = 0.57; P < 0.001). This finding was in agreement with assumptions about the role of muscle fiber type, whereas interindividual comparisons clearly support the fact that other parameters may also contribute to performance during fast movements. Nevertheless, none of the biomechanical features considered in the present study were found to be directly related to the highest angular velocity, highlighting the complexity of the upstream mechanics that lead to maximal-velocity muscle contraction. Copyright © 2015 the American Physiological Society.

  19. Viscoelastic properties of healthy achilles tendon are independent of isometric plantar flexion strength and cross-sectional area.

    PubMed

    Suydam, Stephen M; Soulas, Elizabeth M; Elliott, Dawn M; Silbernagel, Karin Gravare; Buchanan, Thomas S; Cortes, Daniel H

    2015-06-01

    Changes in tendon viscoelastic properties are observed after injuries and during healing as a product of altered composition and structure. Continuous Shear Wave Elastography is a new technique measuring viscoelastic properties of soft tissues using external shear waves. Tendon has not been studied with this technique, therefore, the aims of this study were to establish the range of shear and viscosity moduli in healthy Achilles tendons, determine bilateral differences of these parameters and explore correlations of viscoelasticity to plantar flexion strength and tendon area. Continuous Shear Wave Elastography was performed over the free portion of both Achilles tendons from 29 subjects. Isometric plantar flexion strength and cross sectional area were measured. The average shear and viscous moduli was 83.2 kPa and 141.0 Pa-s, respectively. No correlations existed between the shear or viscous modulus and area or strength. This indicates that viscoelastic properties can be considered novel, independent biomarkers. The shear and viscosity moduli were bilaterally equivalent (p = 0.013, 0.017) which allows determining pathologies through side-to-side deviations. The average bilateral coefficient of variation was 7.2% and 9.4% for shear and viscosity modulus, respectively. The viscoelastic properties of the Achilles tendon may provide an unbiased, non-subjective rating system of tendon recovery and optimizing treatment strategies. © 2015 Orthopaedic Research Society. Published by Wiley Periodicals, Inc.

  20. Viscoelastic Properties of Healthy Achilles Tendon are Independent of Isometric Plantar Flexion Strength and Cross-Sectional Area

    PubMed Central

    Suydam, Stephen M.; Soulas, Elizabeth M.; Elliott, Dawn M.; Silbernagel, Karin Gravare; Buchanan, Thomas S.; Cortes, Daniel H.

    2015-01-01

    Changes in tendon viscoelastic properties are observed after injuries and during healing as a product of altered composition and structure. Continuous Shear Wave Elastography is a new technique measuring viscoelastic properties of soft tissues using external shear waves. Tendon has not been studied with this technique, therefore, the aims of this study were to establish the range of shear and viscosity moduli in healthy Achilles tendons, determine bilateral differences of these parameters and explore correlations of viscoelasticity to plantar flexion strength and tendon area. Continuous Shear Wave Elastography was performed over the free portion of both Achilles tendons from 29 subjects. Isometric plantar flexion strength and cross sectional area were measured. The average shear and viscous moduli was 83.2kPa and 141.0Pa-s, respectively. No correlations existed between the shear or viscous modulus and area or strength. This indicates that viscoelastic properties can be considered novel, independent biomarkers. The shear and viscosity moduli were bilaterally equivalent (p=0.013,0.017) which allows determining pathologies through side-to-side deviations. The average bilateral coefficient of variation was 7.2% and 9.4% for shear and viscosity modulus, respectively. The viscoelastic properties of the Achilles tendon may provide an unbiased, non-subjective rating system of tendon recovery and optimizing treatment strategies. PMID:25882209

  1. Enhanced precision of ankle torque measure with an open-unit dynamometer mounted with a 3D force-torque sensor.

    PubMed

    Toumi, A; Leteneur, S; Gillet, C; Debril, J-F; Decoufour, N; Barbier, F; Jakobi, J M; Simoneau-Buessinger, Emilie

    2015-11-01

    Many studies have focused on maximum torque exerted by ankle joint muscles during plantar flexion. While strength parameters are typically measured with isokinetic or isolated ankle dynamometers, these devices often present substantial limitations for the measurement of torque because they account for force in only 1 dimension (1D), and the device often constrains the body in a position that augments torque through counter movements. The purposes of this study were to determine the contribution of body position to ankle plantar-flexion torque and to assess the use of 1D and 3D torque sensors. A custom designed 'Booted, Open-Unit, Three dimension, Transportable, Ergometer' (B.O.T.T.E.) was used to quantify plantar flexion in two conditions: (1) when the participant was restrained within the unit (locked-unit) and (2) when the participant's position was independent of the ankle dynamometer (open-unit). Ten young males performed maximal voluntary isometric plantar-flexion contractions using the B.O.T.T.E. in open and locked-unit mechanical configurations. The B.O.T.T.E. was reliable with ICC higher than 0.90, and CV lower than 7 %. The plantar-flexion maximal resultant torque was significantly higher in the locked-unit compared with open-unit configuration (P < 0.001; +61 to +157 %) due to the addition of forces from the body being constrained within the testing device. A 1D compared with 3D torque sensor significantly underestimated the proper capacity of plantar-flexion torque production (P < 0.001; -37 to -60 %). Assessment of plantar-flexion torque should be performed with an open-unit dynamometer mounted with a 3D sensor that is exclusive of accessory muscles but inclusive of all ankle joint movements.

  2. Maximal voluntary isokinetic knee flexion torque is associated with femoral shaft bone strength indices in knee replacement patients.

    PubMed

    Rantalainen, T; Valtonen, A; Sipilä, S; Pöyhönen, T; Heinonen, A

    2012-03-01

    It is currently unknown whether knee replacement-associated bone loss is modified by rehabilitation programs. Thus, a sample of 45 (18 men and 25 women) persons with unilateral knee replacement were recruited; age 66 years (sd 6), height 169 cm (sd 8), body mass 83 kg (sd 15), time since operation 10 months (sd 4) to explore the associations between maximal torque/power in knee extension/flexion and femoral mid-shaft bone traits (Cortical cross-sectional area (CoA, mm(2)), cortical volumetric bone mineral density (CoD, mg/mm(3)) and bone bending strength index (SSI, mm(3))). Bone traits were calculated from a single computed tomography slice from the femoral mid-shaft. Pain in the operated knee was assessed with the WOMAC questionnaire. Stepwise regression models were built for the operated leg bone traits, with knee extension and flexion torque and power, age, height, body mass, pain score and time since operation as independent variables. CoA was 2.3% (P=0.015), CoD 1.2% (P<0.001) and SSI 1.6% (P=0.235) lower in the operated compared to non-operated leg. The overall proportions of the variation explained by the regression models were 50%, 29% and 55% for CoA, CoD and SSI, respectively. Body mass explained 12% of Coa, 11% of CoD and 11% of SSI (P≤0.003). Maximal knee flexion torque explained 38% of Coa, 7% of CoD and 44% of SSI (p≤0.047). For CoD time since operation also became a significant predictor (11%, P=0.045). Knee flexion torque of the operated leg was positively associated with bone strength in the operated leg. Thus, successful rehabilitation may diminish bone loss in the operated leg. Copyright © 2011 Elsevier B.V. All rights reserved.

  3. Dynamic interleaved 1H/31P STEAM MRS at 3 Tesla using a pneumatic force-controlled plantar flexion exercise rig

    PubMed Central

    Meyerspeer, M.; Krššák, M.; Kemp, G.J.; Roden, M.; Moser, E.

    2016-01-01

    1 Objective To develop a measurement method for interleaved acquisition of 1H and 31P STEAM localised spectra of exercising human calf muscle. 2 Materials and Methods A nonmagnetic exercise rig with a pneumatic piston and sensors for force and pedal angle was constructed to enable plantar flexion measured in the 3 Tesla MR scanner, which holds the dual tuned (1H,31P) surface coil used for signal transmission and reception. 3 Results 31P spectra acquired in interleaved mode benefit from higher SNR (factor of 1.34± 0.06 for PCr) compared to standard acquisition due to the Nuclear Overhauser effect (NOE) and substantial PCr/Pi changes during exercise can be observed in 31P spectra. 1H spectral quality is equal to that in single mode experiments and allows Cr2 changes to be monitored. 4 Conclusion The feasibility of dynamic interleaved localised 1H and 31P spectroscopy during plantar flexion exercise has been demonstrated using a custom-built pneumatic system for muscle activation. This opens the possibility of studying the dynamics of metabolism with multi nuclear MRS in a single run. PMID:16320091

  4. A restrained-torque-based motion instructor: forearm flexion/extension-driving exoskeleton

    NASA Astrophysics Data System (ADS)

    Nishimura, Takuya; Nomura, Yoshihiko; Sakamoto, Ryota

    2013-01-01

    When learning complicated movements by ourselves, we encounter such problems as a self-rightness. The self-rightness results in a lack of detail and objectivity, and it may cause to miss essences and even twist the essences. Thus, we sometimes fall into the habits of doing inappropriate motions. To solve these problems or to alleviate the problems as could as possible, we have been developed mechanical man-machine human interfaces to support us learning such motions as cultural gestures and sports form. One of the promising interfaces is a wearable exoskeleton mechanical system. As of the first try, we have made a prototype of a 2-link 1-DOF rotational elbow joint interface that is applied for teaching extension-flexion operations with forearms and have found its potential abilities for teaching the initiating and continuing flection motion of the elbow.

  5. Measurement of the end-to-end distances between the femoral and tibial insertion sites of the anterior cruciate ligament during knee flexion and with rotational torque.

    PubMed

    Wang, Joon Ho; Kato, Yuki; Ingham, Sheila J M; Maeyama, Akira; Linde-Rosen, Monica; Smolinski, Patrick; Fu, Freddie H

    2012-10-01

    The aim of this study was to determine the end-to-end distance changes in anterior cruciate ligament (ACL) fibers during flexion/extension and internal/external rotation of the knee. The positional relation between the femur and tibia of 10 knees was digitized on a robotic system during flexion/extension and with an internal/external rotational torque (5 Nm). The ACL insertion site data, acquired by 3-dimensional scanning, were superimposed on the positional data. The end-to-end distances of 5 representative points on the femoral and tibial insertion sites of the ACL were calculated. The end-to-end distances of all representative points except the most anterior points were longest at full extension and shortest at 90°. The distances of the anteromedial (AM) and posterolateral (PL) bundles were 37.2 ± 2.1 mm and 27.5 ± 2.8 mm, respectively, at full extension and 34.7 ± 2.4 mm and 20.7 ± 2.3 mm, respectively, at 90°. Only 4 knees had an isometric point, which was 1 of the 3 anterior points. Under an internal torque, both bundles became longer with statistical meaning at all flexion angles (P = .005). The end-to-end distances of all points became longest with internal torque at full extension and shortest with an external torque at 90°. Only 4 of 10 specimens had an isometric point at a variable anterior point. The end-to-end distances of the AM and PL bundles were longer in extension and shorter in flexion. The nonisometric tendency of the ACL and the end-to-end distance change during knee flexion/extension and internal/external rotation should be considered during ACL reconstruction to avoid overconstraint of the graft. Copyright © 2012 Arthroscopy Association of North America. Published by Elsevier Inc. All rights reserved.

  6. 3D strength surfaces for ankle plantar- and dorsi-flexion in healthy adults: an isometric and isokinetic dynamometry study.

    PubMed

    Hussain, Sara J; Frey-Law, Laura

    2016-01-01

    The ankle is an important component of the human kinetic chain, and deficits in ankle strength can negatively impact functional tasks such as balance and gait. While peak torque is influenced by joint angle and movement velocity, ankle strength is typically reported for a single angle or movement speed. To better identify deficits and track recovery of ankle strength after injury or surgical intervention, ankle strength across a range of movement velocities and joint angles in healthy adults is needed. Thus, the primary goals of this study were to generate a database of strength values and 3-dimensional strength surface models for plantarflexion (PF) and dorsiflexion (DF) ankle strength in healthy men and women. Secondary goals were to develop a means to estimate ankle strength percentiles as well as examine predictors of maximal ankle strength in healthy adults. Using an isokinetic dynamometer, we tested PF and DF peak torques at five joint angles (-10° [DF], 0° [neutral], 10° [PF], 20° [PF] and 30° [PF]) and six velocities (0°/s, 30°/s, 60°/s, 90°/s, 120°/s and 180°/s) in 53 healthy adults. These data were used to generate 3D plots, or "strength surfaces", for males and females for each direction; surfaces were fit using a logistic equation. We also tested predictors of ankle strength, including height, weight, sex, and self-reported physical activity levels. Torque-velocity and torque-angle relationships at the ankle interact, indicating that these relationships are interdependent and best modeled using 3D surfaces. Sex was the strongest predictor of ankle strength over height, weight, and self-reported physical activity levels. 79 to 97 % of the variance in mean peak torque was explained by joint angle and movement velocity using logistic equations, for men and women and PF and DF directions separately. The 3D strength data and surface models provide a more comprehensive dataset of ankle strength in healthy adults than previously reported. These

  7. Magnetic resonance and diffusion tensor imaging analyses indicate heterogeneous strains along human medial gastrocnemius fascicles caused by submaximal plantar-flexion activity.

    PubMed

    Karakuzu, Agah; Pamuk, Uluç; Ozturk, Cengizhan; Acar, Burak; Yucesoy, Can A

    2017-05-24

    Sarcomere length changes are central to force production and excursion of skeletal muscle. Previous modeling indicates non-uniformity of that if mechanical interaction of muscle with its surrounding muscular and connective tissues is taken into account. Hence, quantifying length changes along the fascicles of activated human muscle in vivo is crucial, but this is lacking due to technical complexities. Combining magnetic resonance imaging deformation analyses and diffusion tensor imaging tractography, the aim was to test the hypothesis that submaximal plantar flexion activity at 15% MVC causes heterogeneous length changes along the fascicles of human medial gastrocnemius (GM) muscle. A general fascicle strain distribution pattern shown for all subjects indicates that proximal track segments are shortened, whereas distal ones are lengthened (e.g., by 13% and 29%, respectively). Mean fiber direction strains of different tracts also shows heterogeneity (for up to 57.5% of the fascicles). Inter-subject variability of amplitude and distribution of fascicle strains is notable. These findings confirm the hypothesis and are solid indicators for the functionally dependent mechanics of human muscle, in vivo. Heterogeneity of fascicle strains can be explained by epimuscular myofascial force transmission. To the best of our knowledge, this is the first study, which quantified local deformations along human skeletal muscle fascicles caused by sustained submaximal activation. The present approach and indicated fascicle strain heterogeneity has numerous implications for muscle function in health and disease to estimate the muscle's contribution to the joint moment and excursion and to evaluate mechanisms of muscle injury and several treatment techniques. Copyright © 2017 Elsevier Ltd. All rights reserved.

  8. High-Intensity Running and Plantar-Flexor Fatigability and Plantar-Pressure Distribution in Adolescent Runners

    PubMed Central

    Fourchet, François; Kelly, Luke; Horobeanu, Cosmin; Loepelt, Heiko; Taiar, Redha; Millet, Grégoire

    2015-01-01

    Context: Fatigue-induced alterations in foot mechanics may lead to structural overload and injury. Objectives: To investigate how a high-intensity running exercise to exhaustion modifies ankle plantar-flexor and dorsiflexor strength and fatigability, as well as plantar-pressure distribution in adolescent runners. Design: Controlled laboratory study. Setting: Academy research laboratory. Patients or Other Participants: Eleven male adolescent distance runners (age = 16.9 ± 2.0 years, height = 170.6 ± 10.9 cm, mass = 54.6 ± 8.6 kg) were tested. Intervention(s): All participants performed an exhausting run on a treadmill. An isokinetic plantar-flexor and dorsiflexor maximal-strength test and a fatigue test were performed before and after the exhausting run. Plantar-pressure distribution was assessed at the beginning and end of the exhausting run. Main Outcome Measure(s): We recorded plantar-flexor and dorsiflexor peak torques and calculated the fatigue index. Plantar-pressure measurements were recorded 1 minute after the start of the run and before exhaustion. Plantar variables (ie, mean area, contact time, mean pressure, relative load) were determined for 9 selected regions. Results: Isokinetic peak torques were similar before and after the run in both muscle groups, whereas the fatigue index increased in plantar flexion (28.1%; P = .01) but not in dorsiflexion. For the whole foot, mean pressure decreased from 1 minute to the end (−3.4%; P = .003); however, mean area (9.5%; P = .005) and relative load (7.2%; P = .009) increased under the medial midfoot, and contact time increased under the central forefoot (8.3%; P = .01) and the lesser toes (8.9%; P = .008). Conclusions: Fatigue resistance in the plantar flexors declined after a high-intensity running bout performed by adolescent male distance runners. This phenomenon was associated with increased loading under the medial arch in the fatigued state but without any excessive pronation. PMID:25531143

  9. Tennis in hot and cool conditions decreases the rapid muscle torque production capacity of the knee extensors but not of the plantar flexors

    PubMed Central

    Girard, Olivier; Racinais, Sébastien; Périard, Julien D

    2014-01-01

    Objectives To assess the time course of changes in rapid muscle force/torque production capacity and neuromuscular activity of lower limb muscles in response to prolonged (∼2 h) match-play tennis under heat stress. Methods The rates of torque development (RTD) and electromyographic activity (EMG; ie, root mean square) rise were recorded from 0 to 30, –50, –100 and –200 ms during brief (3–5 s) explosive maximal isometric voluntary contractions (MVC) of the knee extensors (KE) and plantar flexors (PF), along with the peak RTD within the entirety of the torque-time curve. These values were recorded in 12 male tennis players before (prematch) and after (postmatch, 24 and 48 h) match-play in HOT (∼37°C) and COOL (∼22°C) conditions. Results The postmatch core temperature was greater in the HOT (∼39.4°C) vs COOL (∼38.7°C) condition (p<0.05). Reductions in KE RTD occurred within the 0–200 ms epoch after contraction onset postmatch and at 24 h, compared with prematch, independent of environmental conditions (p<0.05). A similar reduction in the KE peak RTD was also observed postmatch relative to prematch (p<0.05). No differences in KE RTD values were observed after normalisation to MVC torque. Furthermore, the rate of KE EMG activity rise remained unchanged. Conversely, the PF contractile RTD and rate of EMG activity rise were unaffected by the exercise or environmental conditions. Conclusions In the KE, a reduction in maximal torque production capacity following prolonged match-play tennis appears to account for the decrease in the rate of torque development, independent of environmental conditions, while remaining unchanged in the PF. PMID:24668381

  10. Healthy older adults have insufficient hip range of motion and plantar flexor strength to walk like healthy young adults.

    PubMed

    Anderson, Dennis E; Madigan, Michael L

    2014-03-21

    Limited plantar flexor strength and hip extension range of motion (ROM) in older adults are believed to underlie common age-related differences in gait. However, no studies of age-related differences in gait have quantified the percentage of strength and ROM used during gait. We examined peak hip angles, hip torques and plantar flexor torques, and corresponding estimates of functional capacity utilized (FCU), which we define as the percentage of available strength or joint ROM used, in 10 young and 10 older healthy adults walking under self-selected and controlled (slow and fast) conditions. Older adults walked with about 30% smaller hip extension angle, 28% larger hip flexion angle, 34% more hip extensor torque in the slow condition, and 12% less plantar flexor torque in the fast condition than young adults. Older adults had higher FCU than young adults for hip flexion angle (47% vs. 34%) and hip extensor torque (48% vs. 27%). FCUs for plantar flexor torque (both age groups) and hip extension angle (older adults in all conditions; young adults in self-selected gait) were not significantly <100%, and were higher than for other measures examined. Older adults lacked sufficient hip extension ROM to walk with a hip extension angle as large as that of young adults. Similarly, in the fast gait condition older adults lacked the strength to match the plantar flexor torque produced by young adults. This supports the hypothesis that hip extension ROM and plantar flexor strength are limiting factors in gait and contribute to age-related differences in gait. Copyright © 2014 Elsevier Ltd. All rights reserved.

  11. Influence of sex on performance fatigability of the plantar flexors following repeated maximal dynamic shortening contractions.

    PubMed

    Lanning, Amelia C; Power, Geoffrey A; Christie, Anita D; Dalton, Brian H

    2017-10-01

    The purpose was to determine sex differences in fatigability during maximal, unconstrained velocity, shortening plantar flexions. The role of time-dependent measures (i.e., rate of torque development, rate of velocity development, and rate of neuromuscular activation) in such sex-related differences was also examined. By task termination, females exhibited smaller reductions in power and similar changes in rate of neuromuscular activation than males, indicating females were less fatigable than males.

  12. Lack of age-specific influence on leg blood flow during incremental calf plantar-flexion exercise in men and women.

    PubMed

    Reilly, Heather; Lane, Louise M; Egaña, Mikel

    2018-05-01

    Age-related exercising leg blood flow (LBF) responses during dynamic knee-extension exercise and forearm blood flow responses during handgrip exercise are preserved in normally active men but attenuated in activity-matched women. We explored whether these age- and sex-specific effects are also apparent during isometric calf plantar-flexion incremental exercise. Normally active young men (YM, n = 15, 24 ± 2 years), young women (YW, n = 8, 22 ± 1 years), older men (OM, n = 13, 70 ± 7 years) and older women (OW, n = 10, 64 ± 7 years) were tested. LBF was measured between contractions using venous occlusion plethysmography. Peak force obtained was higher (P < 0.05) in men compared with women and in young compared with older individuals. However, peak LBF (YM; 971 ± 328 ml min -1 , OM; 985 ± 504 ml min -1 , YW; 844 ± 366 ml min -1 , OW; 960 ± 244 ml min -1 ) and peak leg vascular conductance [LVC = LBF/(MAP + hydrostatic pressure)] responses (YM; 6.0 ± 1.8 ml min -1  mmHg -1 , OM; 5.5 ± 2.8 ml min -1  mmHg -1 , YW; 5.3 ± 2.1 ml min -1  mmHg -1 , OW; 5.5 ± 1.6 ml min -1 mmHg -1 ) were similar among the four groups. Furthermore, the hyperaemic (YM; 8.8 ± 3.7 ml min -1  %F peak -1 OM; 8.3 ± 5.4 ml min -1  %F peak -1 , YW; 8.2 ± 3.5 ml min -1  %F peak -1 , OW; 9.6 ± 2.2 ml min -1  %F peak -1 ) and vasodilatory responses (YM; 0.053 ± 0.020 ml min -1  mmHg -1  %F peak -1 , OM; 0.048 ± 0.028 ml min -1  mmHg -1  %F peak -1 , YW; 0.051 ± 0.019 ml min -1  mmHg -1  %F peak -1 , OW; 0.055 ± 0.014 ml min -1  mmHg -1  %F peak -1 ) were not different among the four groups. These results were accompanied by similar resting LBF responses among groups and were not affected when data were normalised to estimated leg muscle mass. Our results demonstrate that exercising LBF responses during isometric incremental

  13. Torque and Muscle Activation Impairment Along With Insulin Resistance Are Associated With Falls in Women With Fibromyalgia.

    PubMed

    Góes, Suelen M; Stefanello, Joice M F; Homann, Diogo; Lodovico, Angélica; Hubley-Kozey, Cheryl L; Rodacki, André L F

    2016-11-01

    Góes, SM, Stefanello, JMF, Homann, D, Lodovico, A, Hubley-Kozey, CL, and Rodacki, ALF. Torque and muscle activation impairment along with insulin resistance are associated with falls in women with fibromyalgia. J Strength Cond Res 30(11): 3155-3164, 2016-Fibromyalgia (FM) is a chronic pain condition associated with reduced muscle strength, which can lead to functional incapacity and higher risk of falls. The purpose of the study was to compare maximal ankle joint torque, muscle activation, and metabolic changes between women with and without FM. In addition, the relationship between those aspects and retrospectively reported falls in women with FM was determined. Twenty-nine middle-aged women with FM and 30 controls were recruited. Fall history, pain intensity, and pain threshold were assessed. Plasma glucose levels and insulin resistance (IR) were determined. Peak torque and rate of torque development (RTD) were calculated, and muscle activation was assessed from maximum isometric voluntary ankle dorsiflexion and plantar flexion contractions. In addition, voluntary muscle activation failure of the anterior tibialis muscle during maximal dorsiflexion was calculated. When compared to controls, women with FM reported higher number of retrospectively reported falls, exhibited higher IR, showed reduced plantar flexion and dorsiflexion RTD, had lower plantar flexion peak torque, and demonstrated more antagonist coactivation and higher muscle activation failure (p ≤ 0.05). Higher muscle activation failure was explained by glucose level and pain intensity (adj R = 0.28; p ≤ 0.05). Reduced plantar flexion and dorsiflexion peak torque explained 80% of retrospectively reported falls variance; also, high antagonist coactivation (odds ratio [OR] = 1.6; p ≤ 0.05) and high IR (OR = 1.8; p ≤ 0.05) increased the chance of falls in the FM group. A combination of metabolic factors and muscle function increased the odds of retrospectively reporting a fall in FM. Both aspects

  14. Plantar fasciitis

    MedlinePlus

    ... Concepts and Clinical Practice . 8th ed. Philadelphia, PA: Elsevier Saunders; 2014:chap 58. Ferri FF. Plantar fasciitis. ... FF ed. Ferri's Clinical Advisor 2016 . Philadelphia, PA: Elsevier; 2016:970. Kadakia AR. Heel pain and plantar ...

  15. Resistance exercise prevents plantar flexor deconditioning during bed rest

    NASA Technical Reports Server (NTRS)

    Bamman, M. M.; Hunter, G. R.; Stevens, B. R.; Guilliams, M. E.; Greenisen, M. C.

    1997-01-01

    Because resistance exercise (REX) and unloading induce opposing neuromuscular adaptations, we tested the efficacy of REX against the effects of 14 d of bed rest unloading (BRU) on the plantar flexor muscle group. Sixteen men were randomly assigned to no exercise (NOE, N = 8) or REX (N = 8). REX performed 5 sets x 6-10 repetitions to failure of constant resistance concentric/eccentric plantar flexion every other day during BRU. One-repetition maximum (1RM) strength was tested on the training device. The angle-specific torque-velocity relationship across 5 velocities (0, 0.52, 1.05, 1.75, and 2.97 rad.s-1) and the full range-of-motion power-velocity relationship were assessed on a dynamometer. Torque-position analyses identified strength changes at shortened, neutral, and stretched muscle lengths. Concentric and eccentric contractile work were measured across ten repetitions at 1.05 rad.s-1. Maximal neural activation was measured by surface electromyography (EMG). 1RM decreased 9% in NOE and improved 11% in REX (P < 0.05). Concentric (0.52 and 1.05 rad.s-1), eccentric (0.52 and 2.97 rad.s-1), and isometric angle-specific torques decreased (P < 0.05) in NOE, averaging 18%, 17%, and 13%, respectively. Power dropped (P < 0.05) in NOE at three eccentric (21%) and two concentric (14%) velocities. REX protected angle-specific torque and average power at all velocities. Concentric and eccentric strength decreased at stretched (16%) and neutral (17%) muscle lengths (P < 0.05) in NOE while REX maintained or improved strength at all joint positions. Concentric (15%) and eccentric (11%) contractile work fell in NOE (P < 0.05) but not in REX. Maximal plantar flexor EMG did not change in either group. In summary, constant resistance concentric/eccentric REX completely prevented plantar flexor performance deconditioning induced by BRU. The reported benefits of REX should prove useful in prescribing exercise for astronauts in microgravity and for patients susceptible to functional

  16. Muscle activation and the isokinetic torque-velocity relationship of the human triceps surae.

    PubMed

    Harridge, S D; White, M J

    1993-01-01

    The influence of muscle activation and the time allowed for torque generation on the angle-specific torque-velocity relationship of the triceps surae was studied during plantar flexion using supramaximal electrical stimulation and a release technique on six male subjects [mean (SD) age 25 (4) years]. Torque-velocity data were obtained under different levels of constant muscle activation by varying the stimulus frequency and the time allowed for isometric torque generation prior to release and isokinetic shortening. To eliminate the effects of the frequency response on absolute torque the isokinetic data were normalized to the maximum isometric torque values at 0.44 rad. There were no significant differences in the normalized torques generated at any angular velocity using stimulus frequencies of 20, 50 or 80 Hz. When the muscle was stimulated at 50 Hz the torques obtained after a 400 ms and 1 s pre-release isometric contraction did not differ significantly. However, with no pre-release contraction significantly less torque was generated at all angular velocities beyond 1.05 rad.s-1 when compared with either the 200, 400 ms or 1 s condition. With a 200 ms pre-release contraction significantly less torque was generated at angular velocities beyond 1.05 rad.s-1 when compared with the 400 ms or 1 s conditions. It would seem that the major factor governing the shape of the torque-velocity curve at a constant level of muscle activation is the time allowed for torque generation.

  17. Plantar fasciitis.

    PubMed

    Cutts, S; Obi, N; Pasapula, C; Chan, W

    2012-11-01

    In this article we look at the aetiology of plantar fasciitis, the other common differentials for heel pain and the evidence available to support each of the major management options. We also review the literature and discuss the condition. A literature search was performed using PubMed and MEDLINE(®). The following keywords were used, singly or in combination: 'plantar fasciitis', 'plantar heel pain', 'heel spur'. To maximise the search, backward chaining of reference lists from retrieved papers was also undertaken. Plantar fasciitis is a common and often disabling condition. Because the natural history of plantar fasciitis is not understood, it is difficult to distinguish between those patients who recover spontaneously and those who respond to formal treatment. Surgical release of the plantar fascia is effective in the small proportion of patients who do not respond to conservative measures. New techniques such as endoscopic plantar release and extracorporeal shockwave therapy may have a role but the limited availability of equipment and skills means that most patients will continue to be treated by more traditional techniques.

  18. Plantar fasciitis

    PubMed Central

    Cutts, S; Obi, N; Pasapula, C; Chan, W

    2012-01-01

    INTRODUCTION In this article we look at the aetiology of plantar fasciitis, the other common differentials for heel pain and the evidence available to support each of the major management options. We also review the literature and discuss the condition. METHODS A literature search was performed using PubMed and MEDLINE®. The following keywords were used, singly or in combination: ‘plantar fasciitis’, ‘plantar heel pain’, ‘heel spur’. To maximise the search, backward chaining of reference lists from retrieved papers was also undertaken. FINDINGS Plantar fasciitis is a common and often disabling condition. Because the natural history of plantar fasciitis is not understood, it is difficult to distinguish between those patients who recover spontaneously and those who respond to formal treatment. Surgical release of the plantar fascia is effective in the small proportion of patients who do not respond to conservative measures. New techniques such as endoscopic plantar release and extracorporeal shockwave therapy may have a role but the limited availability of equipment and skills means that most patients will continue to be treated by more traditional techniques. PMID:23131221

  19. Maximum voluntary joint torque as a function of joint angle and angular velocity: model development and application to the lower limb.

    PubMed

    Anderson, Dennis E; Madigan, Michael L; Nussbaum, Maury A

    2007-01-01

    Measurements of human strength can be important during analyses of physical activities. Such measurements have often taken the form of the maximum voluntary torque at a single joint angle and angular velocity. However, the available strength varies substantially with joint position and velocity. When examining dynamic activities, strength measurements should account for these variations. A model is presented of maximum voluntary joint torque as a function of joint angle and angular velocity. The model is based on well-known physiological relationships between muscle force and length and between muscle force and velocity and was tested by fitting it to maximum voluntary joint torque data from six different exertions in the lower limb. Isometric, concentric and eccentric maximum voluntary contractions were collected during hip extension, hip flexion, knee extension, knee flexion, ankle plantar flexion and dorsiflexion. Model parameters are reported for each of these exertion directions by gender and age group. This model provides an efficient method by which strength variations with joint angle and angular velocity may be incorporated into comparisons between joint torques calculated by inverse dynamics and the maximum available joint torques.

  20. The effects of passive stretching plus vibration on strength and activation of the plantar flexors.

    PubMed

    Miller, Jonathan D; Herda, Trent J; Trevino, Michael A; Mosier, Eric M

    2016-09-01

    This study examined the effects of passive stretching only (PS+CON) and passive stretching with the addition of continuous vibration (VIB) during post-passive stretching tests (PS+VIB) on peak torque (PT), percent voluntary inactivation (%VI), single stimulus twitch torque (TTSINGLE), and doublet stimuli twitch torque (TTDOUBLET) of the plantar flexors at a short (20° plantar flexion (PF)) and long muscle length (15° dorsiflexion (DF)). Fourteen healthy men (age = 22 ± 3 years) performed isometric maximal voluntary contractions at PF and DF, and passive range of motion (PROM) assessments before and after 8 × 30-s passive stretches without (PS+CON) or with VIB (PS+VIB) administered continuously throughout post-passive stretching tests. The passive properties of the muscle tendon unit were assessed pre- and post-passive stretching via PROM, passive torque (PASSTQ), and musculotendinous stiffness (MTS) measurements. PT, TTSINGLE, and TTDOUBLET decreased, whereas, %VI increased following passive stretching at PF and DF (P < 0.05) with no significant differences between PS+CON and PS+VIB. PASSTQ and MTS decreased while PROM increased post-passive stretching during both trials (P < 0.05). The stretching-induced force/torque deficit and increases in %VI were evident following passive stretching at short and long muscle lengths. Although not statistically significant, effect size calculations suggested large and moderate differences in the absolute changes in PT (Cohen's d = 1.14) and %VI (Cohen's d = 0.54) from pre- to post-passive stretching between treatments, with PS+VIB having greater decreases of PT and higher %VI than PS+CON. The decrement in PT following passive stretching may be primarily neural in origin.

  1. Conservative management of pes valgus with plantar flexed talus, flexible.

    PubMed

    Bleck, E E; Berzins, U J

    1977-01-01

    The type of flat foot that we have called pes valgus with plantar flexed talus, flexible, was treated in children with the Helfet heel seat or the UCBL shoe insert. In follow-up examination of 71 cases for periods longer than one year, 79 per cent of the patients showed that the UCBL shoe insert and the Helfet heel seat improved the clinical and roentgenographic appearance of the foot. The Helfet heel seat is recommended in cases where the plantar flexion angle of the talus is 35 to 45 degrees and the UCBL shoe insert in those cases of plantar flexion of the talus greater than 45 degrees.

  2. Plantar fasciitis

    PubMed Central

    Tahririan, Mohammad Ali; Motififard, Mehdi; Tahmasebi, Mohammad Naghi; Siavashi, Babak

    2012-01-01

    Heel pain, mostly caused by plantar fasciitis (PF), is a common complaint of many patients who requiring professional orthopedic care and are mostly suffering from chronic pain beneath their heels. The present article reviews studies done by preeminent practitioners related to the anatomy of plantar fasciitis and their histo-pathological features, factors associated with PF, clinical features, imaging studies, differential diagnoses, and diverse treatment modalities for treatment of PF, with special emphasis on non-surgical treatment. Anti-inflammatory agents, plantar stretching, and orthosis proved to have highest priority; corticosteroid injection, night splints and extracorporeal shock wave therapy were of next priority, in patients with PF. In patients resistant to the mentioned treatments surgical intervention should be considered. PMID:23798950

  3. Intramuscular pressure and torque during isometric, concentric and eccentric muscular activity

    NASA Technical Reports Server (NTRS)

    Styf, J.; Ballard, R.; Aratow, M.; Crenshaw, A.; Watenpaugh, D.; Hargens, A. R.

    1995-01-01

    Intramuscular pressures, electromyography (EMG) and torque generation during isometric, concentric and eccentric maximal isokinetic muscle activity were recorded in 10 healthy volunteers. Pressure and EMG activity were continuously and simultaneously measured side by side in the tibialis anterior and soleus muscles. Ankle joint torque and position were monitored continuously by an isokinetic dynamometer during plantar flexion and dorsiflexion of the foot. The increased force generation during eccentric muscular activity, compared with other muscular activity, was not accompanied by higher intramuscular pressure. Thus, this study demonstrated that eccentric muscular activity generated higher torque values for each increment of intramuscular pressure. Intramuscular pressures during antagonistic co-activation were significantly higher in the tibilis anterior muscle (42-46% of maximal agonistic activity) compared with the soleus muscle (12-29% of maximal agonistic activity) and was largely due to active recruitment of muscle fibers. In summary, eccentric muscular activity creates higher torque values with no additional increase of the intramuscular pressure compared with concentric and isometric muscular activity.

  4. Restoration of Elbow Flexion.

    PubMed

    Loeffler, Bryan J; Lewis, Daniel R

    2016-08-01

    Active elbow flexion is required to position the hand in space, and loss of this function is debilitating. Nerve transfers or nerve grafts to restore elbow flexion may be options when the target muscle is viable, but in delayed reconstruction when the biceps and brachialis are atrophied or damaged, muscle transfer options should be considered. Muscle transfer options are discussed with attention to the advantages and disadvantages of each transfer option. Copyright © 2016 Elsevier Inc. All rights reserved.

  5. Reciprocal activation of gastrocnemius and soleus motor units is associated with fascicle length change during knee flexion.

    PubMed

    Lauber, Benedikt; Lichtwark, Glen A; Cresswell, Andrew G

    2014-06-01

    While medial gastrocnemius (MG) and soleus (SOL) are considered synergists, they are anatomically exclusive in that SOL crosses only the ankle, while MG crosses both the knee and ankle. Due to the force-length properties of both active and passive structures, activation of SOL and MG must be constantly regulated to provide the required joint torques for any planned movement. As such, the aim of this study was to investigate the neural regulation of MG and SOL when independently changing their length by changing only the knee joint angle, thus exclusively altering the length of MG fibers. MG and SOL motor units (MU) were recorded intramuscularly along with ultrasound imaging of MG and SOL fascicle lengths, while moving the knee through 60° of rotation and maintaining a low level of voluntary plantar flexor torque. The results showed a reciprocal activation of MG and SOL as the knee was moved into flexion and extension. A clear reduction in MG MU firing rates occurred as the knee was flexed (MG fascicles shortening), with de-recruitment of most MG MU occurring at close to full knee flexion. A concomitant increase in SOL MU activity was observed while no change in the length of its fascicles was found. The opposite effects were found when the knee was moved into extension. A strong correlation (ICC = 0.78) was found between the fascicle length at which MG MUs were de-recruited and subsequently re-recruited. This was stronger than the relationship of de-recruitment and re-recruitment with knee angle (ICC = 0.52), indicating that in this instance, muscle fascicle length rather than joint angle is more influential in regulating MG recruitment. Such a reciprocal arrangement like the one presented here for SOL and MG is essential for human voluntary movements such as walking or cycling. © 2014 The Authors. Physiological Reports published by Wiley Periodicals, Inc. on behalf of the American Physiological Society and The Physiological Society.

  6. Potential Relationship between Passive Plantar Flexor Stiffness and Running Performance.

    PubMed

    Ueno, Hiromasa; Suga, Tadashi; Takao, Kenji; Tanaka, Takahiro; Misaki, Jun; Miyake, Yuto; Nagano, Akinori; Isaka, Tadao

    2018-02-01

    The present study aimed to determine the relationship between passive stiffness of the plantar flexors and running performance in endurance runners. Forty-eight well-trained male endurance runners and 24 untrained male control subjects participated in this study. Plantar flexor stiffness during passive dorsiflexion was calculated from the slope of the linear portion of the torque-angle curve. Of the endurance runners included in the present study, running economy in 28 endurance runners was evaluated by measuring energy cost during three 4-min trials (14, 16, and 18 km/h) of submaximal treadmill running. Passive stiffness of the plantar flexors was significantly higher in endurance runners than in untrained subjects. Moreover, passive plantar flexor stiffness in endurance runners was significantly correlated with a personal best 5000-m race time. Furthermore, passive plantar flexor stiffness in endurance runners was significantly correlated with energy cost during submaximal running at 16 km/h and 18 km/h, and a trend towards such significance was observed at 14 km/h. The present findings suggest that stiffer plantar flexors may help achieve better running performance, with greater running economy, in endurance runners. Therefore, in the clinical setting, passive stiffness of the plantar flexors may be a potential parameter for assessing running performance. © Georg Thieme Verlag KG Stuttgart · New York.

  7. Spine lateral flexion strength development differences between exercises with pelvic stabilization and without pelvic stabilization

    NASA Astrophysics Data System (ADS)

    Straton, Alexandru; Gidu, Diana Victoria; Micu, Alexandru

    2015-02-01

    Poor lateral flexor muscle strength can be an important source of lumbar/thoracic back pain in women. The purpose of this study was to evaluate pelvic stabilization (PS) and no pelvic stabilization (NoPS) lateral flexion strength exercise training on the development of isolated right and left lateral flexion strength. Isometric torque of the isolated right and left lateral flexion muscles was measured at two positions (0° and 30° opposed angle range of motion) on 42 healthy women before and after 8 weeks of PS and NoPS lateral flexion strength exercise training. Subjects were assigned in three groups, the first (n=14) trained 3 times/week with PS lateral flexion strength exercise, the second (n=14) trained 3 times/week with NoPS lateral flexion strength exercise and the third (control, n=14) did not train. Post training isometric strength values describing PS and NoPS lateral flexion strength improved in greater extent for the PS lateral flexion strength exercise group and in lesser extent for the NoPS lateral flexion strength exercise group, in both angles (p<0.05) relative to controls. These data indicate that the most effective way of training the spine lateral flexion muscles is PS lateral flexion strength exercises; NoPS lateral flexion strength exercises can be an effective way of training for the spine lateral flexion muscles, if there is no access to PS lateral flexion strength training machines.

  8. Flexion in Abell 2744

    NASA Astrophysics Data System (ADS)

    Bird, J. P.; Goldberg, D. M.

    2018-05-01

    We present the first flexion-focused gravitational lensing analysis of the Hubble Frontier Field observations of Abell 2744 (z = 0.308). We apply a modified Analytic Image Model technique to measure source galaxy flexion and shear values at a final number density of 82 arcmin-2. By using flexion data alone, we are able to identify the primary mass structure aligned along the heart of the cluster in addition to two major substructure peaks, including an NE component that corresponds to previous lensing work and a new peak detection offset 1.43 arcmin from the cluster core towards the east. We generate two types of non-parametric reconstructions: flexion aperture mass maps, which identify central core, E, and NE substructure peaks with mass signal-to-noise contours peaking at 3.5σ, 2.7σ, and 2.3σ, respectively; and convergence maps derived directly from the smoothed flexion field. For the primary peak, we find a mass of (1.62 ± 0.12) × 1014 h-1 M⊙ within a 33 arcsec (105 h-1 kpc) aperture, a mass of (2.92 ± 0.26) × 1013 h-1 M⊙ within a 16 arcsec (50 h-1 kpc) aperture for the north-eastern substructure, and (8.81 ± 0.52) × 1013 h-1 M⊙ within a 25 arcsec (80 h-1 kpc) aperture for the novel eastern substructure.

  9. Comparison of joint torque evoked with monopolar and tripolar-cuff electrodes.

    PubMed

    Tarler, Matthew D; Mortimer, J Thomas

    2003-09-01

    Using a self-sizing spiral-cuff electrode placed on the sciatic nerve of the cat, the joint torque evoked with stimulation applied to contacts in a monopolar configuration was judged to be the same as the torque evoked by stimulation applied to contacts in a tripolar configuration. Experiments were carried out in six acute cat preparations. In each experiment, a 12-contact electrode was placed on the sciatic nerve and used to effect both the monopolar and tripolar electrode configurations. The ankle torque produced by electrically evoked isometric muscle contraction was measured in three dimensions: plantar flexion, internal rotation, and inversion. Based on the recorded ankle torque, qualitative and quantitative comparisons were performed to determine if any significant difference existed in the pattern or order in which motor nerve fibers were recruited. No significant difference was found at a 98% confidence interval in either the recruitment properties or the repeatability of the monopolar and tripolar configurations. Further, isolated activation of single fascicles within the sciatic nerve was observed. Once nerve fibers in a fascicle were activated, recruitment of that fascicle was modulated over the full range before "spill-over" excitation occurred in neighboring fascicles. These results indicate that a four contact, monopolar nerve-cuff electrode is a viable substitute for a 12 contact, tripolar nerve-cuff electrode. The results of this study are also consistent with the hypothesis that multicontact self-sizing spiral-cuff electrodes can be used in motor prostheses to provide selective control of many muscles. These findings should also apply to other neuroprostheses employing-cuff electrodes on nerve trunks.

  10. Gait-related strategies for the prevention of plantar ulcer development in the high risk foot.

    PubMed

    Bowling, Frank L; Reeves, Neil D; Boulton, Andrew J

    2011-05-01

    High plantar pressures lead to ulceration in the diabetic foot, particularly in the forefoot region around the metatarsal heads. High plantar pressures persist during gait due to factors such as peripheral neuropathy, foot deformities, limited ankle dorsi flexion range of motion and reduced plantar tissue thickness. Strategies impinging upon gait such as the use of appropriate therapeutic footwear, custom-moulded insoles and injectable silicone can help to reduce plantar pressures and attenuate the risk for ulceration. Shoes adapted with external rocker profiles facilitate plantar flexion and restrict sagittal plane motion of the metatarsophalangeal joint, reducing pressures in the region of the metatarsal heads. Insoles custom-moulded to patient's feet help to reduce plantar pressures and minimise the risk of ulceration in the forefoot region. The loss of subcutaneous fat tissue in the diabetic foot enhances bony prominences and predisposes the foot to high-pressure areas. Silicone is a biocompatible material that can be safely injected into plantar soft tissue to augment tissue thickness and prevent the development of ulceration. This enhancement to the subcutaneous layer is remarkably well retained and is a generally well-adopted procedure in the clinical setting.

  11. Endoscopic Plantar Fascia Debridement for Chronic Plantar Fasciitis.

    PubMed

    Cottom, James M; Baker, Joseph S

    2016-10-01

    When conservative therapy fails for chronic plantar fasciitis, surgical intervention may be an option. Surgical techniques that maintain the integrity of the plantar fascia will have less risk of destabilizing the foot and will retain foot function. Endoscopic debridement of the plantar fascia can be performed reproducibly to reduce pain and maintain function of the foot. Copyright © 2016 Elsevier Inc. All rights reserved.

  12. Plantar Fasciitis: A Concise Review

    PubMed Central

    Schwartz, Emily N; Su, John

    2014-01-01

    One challenge in the treatment of plantar fasciitis is that very few high-quality studies exist comparing different treatment modalities to guide evidence-based management. Current literature suggests a change to the way that plantar fasciitis is managed. This article reviews the most current literature on plantar fasciitis and showcases recommended treatment guidelines. This serves to assist physicians in diagnosing and treating heel pain with plantar fasciitis. PMID:24626080

  13. Plantar fasciitis: a concise review.

    PubMed

    Schwartz, Emily N; Su, John

    2014-01-01

    One challenge in the treatment of plantar fasciitis is that very few high-quality studies exist comparing different treatment modalities to guide evidence-based management. Current literature suggests a change to the way that plantar fasciitis is managed. This article reviews the most current literature on plantar fasciitis and showcases recommended treatment guidelines. This serves to assist physicians in diagnosing and treating heel pain with plantar fasciitis.

  14. Torque sensor

    NASA Astrophysics Data System (ADS)

    Fgeppert, E.

    1984-09-01

    Mechanical means for sensing turning torque generated by the load forces in a rotary drive system is described. The sensing means is designed to operate with minimal effect on normal operation of the drive system. The invention can be employed in various drive systems, e.g., automotive engine-transmission power plants, electric motor-operated tools, and metal cutting machines. In such drive systems, the torque-sensing feature may be useful for actuation of various control devices, such as electric switches, mechanical clutches, brake actuators, fluid control valves, or audible alarms. The torque-sensing function can be used for safety overload relief, motor de-energization, engine fuel control transmission clutch actuation, remote alarm signal, tool breakage signal, etc.

  15. Plantar Hyperhidrosis: An Overview.

    PubMed

    Vlahovic, Tracey C

    2016-07-01

    Plantar hyperhidrosis, excessive sweating on the soles of feet, can have a significant impact on patients' quality of life and emotional well-being. Hyperhidrosis is divided into primary and secondary categories, depending on the cause of the sweating, with plantar hyperhidrosis typically being primary and idiopathic. There is an overall increased risk of cutaneous infection in the presence of hyperhidrosis, including fungal, bacterial, and viral infections. This article discusses a range of treatment options including topical aluminum chloride, iontophoresis, injectable botulinum toxin A, glycopyrrolate, oxybutynin, laser, and endoscopic lumbar sympathectomy. Lifestyle changes regarding hygiene, shoe gear, insoles, and socks are also discussed. Copyright © 2016 Elsevier Inc. All rights reserved.

  16. Talalgia: plantar fasciitis☆

    PubMed Central

    Cardenuto Ferreira, Ricardo

    2014-01-01

    Plantar fasciitis is a very common painful syndrome, but its exact etiology still remains obscure. The diagnosis is essentially clinical, based on history-taking and physical examination. Complementary laboratory tests and imaging examinations may be useful for differential diagnoses. The treatment is essentially conservative, with a high success rate (around 90%). The essence of the conservative treatment is the home-based program of exercises to stretch the plantar fascia. Indications for surgical treatment are only made when the symptoms persist without significant improvement, after at least six months of conservative treatment supervised directly by the doctor. PMID:26229803

  17. Age-related reduction of trunk muscle torque and prevalence of trunk sarcopenia in community-dwelling elderly: Validity of a portable trunk muscle torque measurement instrument and its application to a large sample cohort study

    PubMed Central

    Sasaki, Shizuka; Chiba, Daisuke; Yamamoto, Yuji; Nawata, Atsushi; Tsuda, Eiichi; Nakaji, Shigeyuki; Ishibashi, Yasuyuki

    2018-01-01

    Trunk muscle weakness and imbalance are risk factors for postural instability, low back pain, and poor postoperative outcomes. The association between trunk muscle strength and aging is poorly understood, and establishing normal reference values is difficult. We aimed to establish the validity of a novel portable trunk muscle torque measurement instrument (PTMI). We then estimated reference data for healthy young adults and elucidated age-related weakness in trunk muscle strength. Twenty-four university students were enrolled to validate values for PTMI, and 816 volunteers from the general population who were recruited to the Iwaki Health Promotion Project were included to estimate reference data for trunk muscle strength. Trunk flexion and extension torque were measured with PTMI and KinCom, and interclass correlation coefficients (ICC) were estimated to evaluate the reliability of PTMI values. Furthermore, from the young adult reference, the age-related reduction in trunk muscle torque and the prevalence of sarcopenia among age-sex groups were estimated. The ICC in flexion and extension torque were 0.807 (p<0.001) and 0.789 (p<0.001), respectively. The prevalence of sarcopenia increased with age, and the prevalence due to flexion torque was double that of extension torque. Flexion torque decreased significantly after 60 years of age, and extension torque decreased after 70 years of age. In males over age 80, trunk muscle torque decreased to 49.1% in flexion and 63.5% in extension. In females over age 80, trunk muscle torque decreased to 60.7% in flexion and 68.4% in extension. The validity of PTMI was confirmed by correlation with KinCom. PTMI produced reference data for healthy young adults, and demonstrated age-related reduction in trunk muscle torque. Trunk sarcopenia progressed with aging, and the loss of flexion torque began earlier than extension torque. At age 80, trunk muscle torque had decreased 60% compared with healthy young adults. PMID:29471310

  18. Age-related reduction of trunk muscle torque and prevalence of trunk sarcopenia in community-dwelling elderly: Validity of a portable trunk muscle torque measurement instrument and its application to a large sample cohort study.

    PubMed

    Sasaki, Eiji; Sasaki, Shizuka; Chiba, Daisuke; Yamamoto, Yuji; Nawata, Atsushi; Tsuda, Eiichi; Nakaji, Shigeyuki; Ishibashi, Yasuyuki

    2018-01-01

    Trunk muscle weakness and imbalance are risk factors for postural instability, low back pain, and poor postoperative outcomes. The association between trunk muscle strength and aging is poorly understood, and establishing normal reference values is difficult. We aimed to establish the validity of a novel portable trunk muscle torque measurement instrument (PTMI). We then estimated reference data for healthy young adults and elucidated age-related weakness in trunk muscle strength. Twenty-four university students were enrolled to validate values for PTMI, and 816 volunteers from the general population who were recruited to the Iwaki Health Promotion Project were included to estimate reference data for trunk muscle strength. Trunk flexion and extension torque were measured with PTMI and KinCom, and interclass correlation coefficients (ICC) were estimated to evaluate the reliability of PTMI values. Furthermore, from the young adult reference, the age-related reduction in trunk muscle torque and the prevalence of sarcopenia among age-sex groups were estimated. The ICC in flexion and extension torque were 0.807 (p<0.001) and 0.789 (p<0.001), respectively. The prevalence of sarcopenia increased with age, and the prevalence due to flexion torque was double that of extension torque. Flexion torque decreased significantly after 60 years of age, and extension torque decreased after 70 years of age. In males over age 80, trunk muscle torque decreased to 49.1% in flexion and 63.5% in extension. In females over age 80, trunk muscle torque decreased to 60.7% in flexion and 68.4% in extension. The validity of PTMI was confirmed by correlation with KinCom. PTMI produced reference data for healthy young adults, and demonstrated age-related reduction in trunk muscle torque. Trunk sarcopenia progressed with aging, and the loss of flexion torque began earlier than extension torque. At age 80, trunk muscle torque had decreased 60% compared with healthy young adults.

  19. Effect of Achilles tendon loading on plantar fascia tension in the standing foot.

    PubMed

    Cheung, Jason Tak-Man; Zhang, Ming; An, Kai-Nan

    2006-02-01

    The plantar fascia, which is one of the major arch-supporting structures of the human foot, sustains high tensions during weight-bearing. A positive correlation between Achilles tendon loading and plantar fascia tension has been reported. Excessive stretching and tightness of the Achilles tendon are thought to be the risk factors of plantar fasciitis but their biomechanical effects on the plantar fascia have not been fully addressed. A three-dimensional finite element model of the human foot and ankle, incorporating geometrical and material nonlinearity, was employed to investigate the loading response of the plantar fascia in the standing foot with different magnitudes of Achilles tendon loading. With the total ground reaction forces of one foot maintained at 350 N to represent half body weight, an increase in Achilles tendon load from (0-700 N) resulted in a general increase in total force and peak plantar pressure at the forefoot of up to about 250%. There was a lateral and anterior shift of the centre of pressure and a reduction in the arch height with an increasing Achilles tendon load as a result of the plantar flexion moment on the calcaneus. From the finite element predictions of simulated balanced standing, Achilles tendon forces of 75% of the total weight on the foot (350 N) were found to provide the closest match of the measured centre of pressure of the subject during balanced standing. Both the weight on the foot and Achilles tendon loading resulted in an increase in tension of the plantar fascia with the latter showing a two-times larger straining effect. Increasing tension on the Achilles tendon is coupled with an increasing strain on the plantar fascia. Overstretching of the Achilles tendon resulting from intense muscle contraction and passive stretching of tight Achilles tendon are plausible mechanical factors for overstraining of the plantar fascia.

  20. Strength training for plantar fasciitis and the intrinsic foot musculature: A systematic review.

    PubMed

    Huffer, Dean; Hing, Wayne; Newton, Richard; Clair, Mike

    2017-03-01

    The aim was to critically evaluate the literature investigating strength training interventions in the treatment of plantar fasciitis and improving intrinsic foot musculature strength. A search of PubMed, CINHAL, Web of Science, SPORTSDiscus, EBSCO Academic Search Complete and PEDRO using the search terms plantar fasciitis, strength, strengthening, resistance training, intrinsic flexor foot, resistance training. Seven articles met the eligibility criteria. Methodological quality was assessed using the modified Downs and Black checklist. All articles showed moderate to high quality, however external validity was low. A comparison of the interventions highlights significant differences in strength training approaches to treating plantar fasciitis and improving intrinsic strength. It was not possible to identify the extent to which strengthening interventions for intrinsic musculature may benefit symptomatic or at risk populations to plantar fasciitis. There is limited external validity that foot exercises, toe flexion against resistance and minimalist running shoes may contribute to improved intrinsic foot musculature function. Despite no plantar fascia thickness changes being observed through high-load plantar fascia resistance training there are indications that it may aid in a reduction of pain and improvements in function. Further research should use standardised outcome measures to assess intrinsic foot musculature strength and plantar fasciitis symptoms. Copyright © 2016 Elsevier Ltd. All rights reserved.

  1. The effect of trunk flexion on lower-limb kinetics of able-bodied gait.

    PubMed

    Kluger, David; Major, Matthew J; Fatone, Stefania; Gard, Steven A

    2014-02-01

    Able-bodied individuals spontaneously adopt crouch gait when walking with induced anterior trunk flexion, but the effect of this adaptation on lower-limb kinetics is unknown. Sustained forward trunk displacement during walking can greatly alter body center-of-mass location and necessitate a motor control response to maintain upright balance. Understanding this response may provide insight into the biomechanical demands on the lower-limb joints of spinal pathology that alter trunk alignment (e.g., flatback). The purpose of this study was to determine the effect of sustained trunk flexion on lower-limb kinetics in able-bodied gait, facilitating understanding of the effects of spinal pathologies. Subjects walked with three postures: 0° (normal upright), 25±7°, and 50±7° trunk flexion. With increased trunk flexion, decreased peak ankle plantar flexor moments were observed with increased energy absorption during stance. Sustained knee flexion during mid- and terminal stance decreased knee flexor moments, but energy absorption/generation remained unchanged across postures. Increased trunk flexion placed significant demand on the hip extensors, thus increasing peak hip extensor moments and energy generation. The direct relationship between trunk flexion and energy absorption/generation at the ankle and hip, respectively, suggest increased muscular demand during gait. These findings on able-bodied subjects might shed light on muscular demands associated with individuals having pathology-induced positive sagittal spine balance. Copyright © 2013 Elsevier B.V. All rights reserved.

  2. Knee Extensor and Flexor Torque Development with Concentric and Eccentric Isokinetic Training

    ERIC Educational Resources Information Center

    Miller, Larry E.; Pierson, Lee M.; Nickols-Richardson, Sharon M.; Wootten, David F.; Selmon, Serah E.; Ramp, Warren K.; Herbert, William G.

    2006-01-01

    This study assessed muscular torque and rate of torque development following concentric (CON) or eccentric (ECC) isokinetic training. Thirty-eight women were randomly assigned to either CON or ECC training groups. Training consisted of knee extension and flexion of the nondominant leg three times per week for 20 weeks (SD = 1). Eccentric training…

  3. Primary Care Management of Plantar Fasciitis.

    PubMed

    Melvin, Thomas J; Tankersley, Zach J; Qazi, Zain N; Jasko, John J; Odono, Russell; Shuler, Franklin D

    2015-01-01

    Plantar fasciitis (PF) is present in 10% of the population and is the most common cause of plantar heel pain. PF is painful, can alter daily activities and presents as a sharp pain localized to the plantar foot and medial heel. The underlying etiology involves microtrauma to the plantar fascia, specifically at its insertion point on the calcaneus. Successful management of plantar fasciitis is typically achieved with the conservative therapy approaches discussed.

  4. Acute Medial Plantar Fascia Tear.

    PubMed

    Pascoe, Stephanie C; Mazzola, Timothy J

    2016-06-01

    A 32-year-old man who participated in competitive soccer came to physical therapy via direct access for a chief complaint of plantar foot pain. The clinical examination findings and mechanism of injury raised a concern for a plantar fascia tear, so the patient was referred to the physician and magnetic resonance imaging was obtained. The magnetic resonance image confirmed a high-grade, partial-thickness, proximal plantar fascia tear with localized edema at the location of the medial band. J Orthop Sports Phys Ther 2016;46(6):495. doi:10.2519/jospt.2016.0409.

  5. Treatment of Chronic Plantar Fasciitis With Percutaneous Latticed Plantar Fasciotomy.

    PubMed

    Yanbin, Xu; Haikun, Chu; Xiaofeng, Ji; Wanshan, Yang; Shuangping, Liu

    2015-01-01

    Plantar fasciitis, the most common cause of pain in the inferior heel, accounts for 11% to 15% of all foot symptoms requiring professional care among adults. The present study reports the results of a minimally invasive surgical treatment of chronic plantar fasciitis. All patients with plantar fasciitis who had undergone percutaneous latticed plantar fasciotomy at 3 clinical sites from March 2008 to March 2009 were included in the present study. The follow-up evaluations for this treatment were conducted using the Mayo clinical scoring system. We investigated 17 patients with recalcitrant chronic plantar fasciitis who had undergone this treatment within a follow-up period of ≥13 months. All procedures were performed in the clinic with the patient under local anesthesia. No wound infections or blood vessel or nerve damage occurred. At a mean follow-up period of 16.0 ± 2.29 (range 13 to 21) months, significant improvement was seen in the preoperative mean Mayo score (from 12.06 ± 2.54 to 89.76 ± 4.28, p < .001) and no patient had developed symptom recurrence. Also, none of the patients had developed complex regional pain syndrome. All patients were able to return to regular shoe wear by 3 weeks postoperatively. The technique of plantar fasciitis with percutaneous latticed plantar fasciotomy could be a promising treatment option for patients with recalcitrant chronic plantar fasciitis. Copyright © 2015 American College of Foot and Ankle Surgeons. Published by Elsevier Inc. All rights reserved.

  6. A flap based on the plantar digital artery arch branch to improve appearance of reconstructed fingers: Anatomical and clinical application.

    PubMed

    Tang, Lin-Feng; Ju, Ji-Hui; Liu, Yue-Fei; Lan, Bo; Hou, Rui-Xing

    2018-02-01

    To investigate blood supply features of the flap based on the plantar digital artery arch and arch branch artery, and the treatment of outcomes of reconstructed fingers by the plantar digital artery arch branch island flap. Eight fresh foot specimens were employed with red emulsion infusion and microdissection. The vascular organization was observed in the second toe, such as initiation site, the course, and the number of the plantar digital artery arch branch. There were 15 fingers of 13 patients (8 males and 5 females) with finger defects accompanied by toe transfer, using the plantar digital artery arch branch flap inserted in the neck of the second toe to correct the appearance defect caused by a narrow "neck" and a bulbous tip. The intact plantar digital arches were identified in all specimens. The plantar digital artery arch had 5 branches. The range of external diameter of the arch branch was 0.4-0.6 mm. All the plantar digital artery arch branch island flaps and the reconstructed fingers survived. These cases were conducted with a follow-up period for 3-18 months (average, 9 months). All the plantar digital artery arch branch island flaps and reconstructed fingers demonstrated a satisfactory appearance and favorable sense function. The reconstructed finger-tip characteristic was good, with no obvious scar hyperplasia. The range of flexion and extension of reconstructed fingers was favorable as well. The plantar digital artery arch and arch branch artery possess regular vasa vasorum and abundant vascularity. A flap based on the plantar digital artery arch branch is an ideal selection for plastic surgery of reconstructed fingers. Copyright © 2017 British Association of Plastic, Reconstructive and Aesthetic Surgeons. Published by Elsevier Ltd. All rights reserved.

  7. How joint torques affect hamstring injury risk in sprinting swing-stance transition.

    PubMed

    Sun, Yuliang; Wei, Shutao; Zhong, Yunjian; Fu, Weijie; Li, Li; Liu, Yu

    2015-02-01

    The potential mechanisms of hamstring strain injuries in athletes are not well understood. The study, therefore, was aimed at understanding hamstring mechanics by studying loading conditions during maximum-effort overground sprinting. Three-dimensional kinematics and ground reaction force data were collected from eight elite male sprinters sprinting at their maximum effort. Maximal isometric torques of the hip and knee were also collected. Data from the sprinting gait cycle were analyzed via an intersegmental dynamics approach, and the different joint torque components were calculated. During the initial stance phase, the ground reaction force passed anteriorly to the knee and hip, producing an extension torque at the knee and a flexion torque at the hip joint. Thus, the active muscle torque functioned to produce flexion torque at the knee and extension torque at the hip. The maximal muscle torque at the knee joint was 1.4 times the maximal isometric knee flexion torque. During the late swing phase, the muscle torque counterbalanced the motion-dependent torque and acted to flex the knee joint and extend the hip joint. The loading conditions on the hamstring muscles were similar to those of the initial stance phase. During both the initial stance and late swing phases, the large passive torques at both the knee and hip joints acted to lengthen the hamstring muscles. The active muscle torques generated mainly by the hamstrings functioned to counteract those passive effects. As a result, during sprinting or high-speed locomotion, the hamstring muscles may be more susceptible to high risk of strain injury during these two phases.

  8. How Joint Torques Affect Hamstring Injury Risk in Sprinting Swing–Stance Transition

    PubMed Central

    SUN, YULIANG; WEI, SHUTAO; ZHONG, YUNJIAN; FU, WEIJIE; LI, LI; LIU, YU

    2015-01-01

    ABSTRACT Purpose The potential mechanisms of hamstring strain injuries in athletes are not well understood. The study, therefore, was aimed at understanding hamstring mechanics by studying loading conditions during maximum-effort overground sprinting. Methods Three-dimensional kinematics and ground reaction force data were collected from eight elite male sprinters sprinting at their maximum effort. Maximal isometric torques of the hip and knee were also collected. Data from the sprinting gait cycle were analyzed via an intersegmental dynamics approach, and the different joint torque components were calculated. Results During the initial stance phase, the ground reaction force passed anteriorly to the knee and hip, producing an extension torque at the knee and a flexion torque at the hip joint. Thus, the active muscle torque functioned to produce flexion torque at the knee and extension torque at the hip. The maximal muscle torque at the knee joint was 1.4 times the maximal isometric knee flexion torque. During the late swing phase, the muscle torque counterbalanced the motion-dependent torque and acted to flex the knee joint and extend the hip joint. The loading conditions on the hamstring muscles were similar to those of the initial stance phase. Conclusions During both the initial stance and late swing phases, the large passive torques at both the knee and hip joints acted to lengthen the hamstring muscles. The active muscle torques generated mainly by the hamstrings functioned to counteract those passive effects. As a result, during sprinting or high-speed locomotion, the hamstring muscles may be more susceptible to high risk of strain injury during these two phases. PMID:24911288

  9. Botulinum toxin effects on gasatrocnemius strength and plantar pressure in diabetics with peripheral neuropathy and forefoot ulceration.

    PubMed

    Hastings, Mary K; Mueller, Michael J; Sinacore, David R; Strube, Michael J; Crowner, Beth E; Johnson, Jeffrey E; Racette, Brad R

    2012-05-01

    High forefoot plantar pressure is associated with plantar ulcers in people with diabetes and peripheral neuropathy. The purpose of this pilot study was to determine the safety and efficacy of botulinum toxin A injected into the gastrocnemius-soleus muscles to reduce muscle strength and plantar pressure. This double blind, randomized clinical trial studied 17 people with diabetes mellitus, peripheral neuropathy and a forefoot plantar ulcer. Subjects were randomized into one of three groups receiving gastrocnemius-soleus muscle injections on the involved side with; 1) Saline (n = 5, weight =99± 21 kg), 2) 200-units of Botox® (n = 7, weight = 101± 5 kg), or 3) 300-units of Botox® (n = 5, weight = 129± 22 kg). Botox® dose was converted to units/kg, the majority received between 1.9 and 2.4 units/kg (n = 11) and one 3.2 units/kg. Plantarflexor peak torque and forefoot peak plantar pressure were quantified prior and 2 weeks post-injection. There were no complications from the injections. Plantarflexor peak torque on the involved side increased in the placebo and 300 groups (3± 4 Nm and 6± 10 Nm, respectively) and decreased -8± 11 Nm in the 200 group. There was no relationship between units/kg of Botox® for each subject and change in plantarflexor peak torque. Forefoot peak plantar pressure did not change in the placebo and 300 groups (0± 11 and 0± 5 N/cm(2), respectively) and decreased -4± 16 N/cm2 (4%) for the 200 group. There were no adverse events associated with the Botox® injections. This study was unable to determine the dose to consistently reduce plantarflexor strength and forefoot plantar pressure. Additional research is needed to investigate diabetes mellitus specific physiological changes and their impact of BoNT-A effectiveness in order to guide appropriate dosing.

  10. Hip abductor, trunk extensor and ankle plantar flexor endurance in females with and without patellofemoral pain.

    PubMed

    Van Cant, Joachim; Pitance, Laurent; Feipel, Véronique

    2017-01-01

    Previous studies have reported strength deficit in hip abduction, extension and external rotation in females with patellofemoral pain (PFP) when compared with healthy control; however, there is conflicting evidence for a decrease in hip muscle endurance. Therefore, it seems important to evaluate hip muscle endurance in females with PFP. Moreover, trunk extensor and ankle plantar flexor endurance have not yet been evaluate in females with PFP. To compare hip abductor, trunk extensor and ankle plantar flexor endurance between females with and without PFP. Twenty females with PFP (mean age, 21.1 years) and 76 healthy females (mean age, 20.5 years) were recruited. Subject performed three endurance clinical tests: (1) The hip abductor isometric endurance test, (2) The Sorensen test and (3) The heel rise test. Group differences were assessed using an independent t tests, or Mann-Whitney U tests for non-normally distributed data. Subjects with PFP exhibited significantly lower hip abductor, trunk extensor and ankle plantar flexor endurance than healthy controls. On average, subjects with PFP had deficits of 16% in hip abduction, 14% in trunk extension and 26% in ankle plantar flexion. Females with PFP exhibited diminished hip abductor, trunk extensor and ankle plantar flexor endurance compared to healthy controls.

  11. Plantar fascia: imaging diagnosis and guided treatment.

    PubMed

    McNally, Eugene G; Shetty, Shilpa

    2010-09-01

    Plantar fasciopathy is a common cause of heel pain. This article covers the imaging anatomy of the hindfoot, the imaging findings on ultrasound and magnetic resonance imaging (MRI) of plantar fasciopathy, plantar fibromas, trauma, Achilles tendonopathy, neural compression, stress fractures of the os calcis and other heel pad lesions. Thickening of the plantar fascia insertion more than 5 mm either on ultrasound or MRI is suggestive of plantar fasciopathy. Ultrasound is superior to MRI for diagnosis of plantar fibroma as small low signal lesions on MRI are similar to the normal plantar fascia signal. Ultrasound demonstrates low echogenicity compared with the echogenic plantar fascia. Penetrating injuries can appear bizarre due to associated foreign body impaction and infection. Achilles tendonopathy can cause heel pain and should be considered as a possible diagnosis. Treatment options include physical therapy, ECSWT, corticosteroid injection, and dry needling. Percutaneous US guided treatment methods will be described. Thieme Medical Publishers.

  12. Factors Associated With Callus in Patients with Diabetes, Focused on Plantar Shear Stress During Gait.

    PubMed

    Hamatani, Masako; Mori, Taketoshi; Oe, Makoto; Noguchi, Hiroshi; Takehara, Kimie; Amemiya, Ayumi; Ohashi, Yumiko; Ueki, Kohjiro; Kadowaki, Takashi; Sanada, Hiromi

    2016-11-01

    The aim of this study is to identify whether plantar shear stress in neuropathic patients with diabetes with callus is increased compared with those without callus. The differences in foot deformity, limited joint mobility, repetitive stress of walking, and ill-fitting shoes between patients with callus and those without callus were also determined. Subjects were recruited from the Diabetic Foot Outpatient Clinic. A newly developed in-shoe measurement system, which has flexible and thin insoles, enabled measurement of both plantar pressure and shear stress simultaneously when subjects walked as usual on a 10 m walkway. It was found that plantar shear stress adjusted for weight during the push-off phase was increased by 1.32 times in patients with callus compared with those without callus (mean ± SD: 0.0500 ± 0.0160 vs 0.0380 ± 0.0144, P = .031). Moreover, hallux valgus deformity, reduction in dorsiflexion of the ankle joint and increase in plantar flexion were showed in feet with callus. Increased plantar shear stress may be caused by gait change that patients having callus push off with the metatarsal head instead of the toe as a result of foot deformity and limited joint mobility. It was found that plantar shear stress adjusted for weight during the push-off phase was increased in patients with callus compared with those without callus by using the newly developed measurement system. These results suggest that reduction of plantar shear stress during the push-off phase can prevent callus formation in neuropathic patients with diabetes. © 2016 Diabetes Technology Society.

  13. Selective plantar fascia release for nonhealing diabetic plantar ulcerations.

    PubMed

    Kim, J Young; Hwang, Seungkeun; Lee, Yoonjung

    2012-07-18

    Achilles tendon lengthening can decrease plantar pressures, leading to resolution of forefoot ulceration in patients with diabetes mellitus. However, this procedure has been reported to have a complication rate of 10% to 30% and can require a long period of postoperative immobilization. We have developed a new technique, selective plantar fascia release, as an alternative to Achilles tendon lengthening for managing these forefoot ulcers. We evaluated sixty patients with diabetes for a mean of 23.5 months after selective plantar fascia release for the treatment of nonhealing diabetic neuropathic ulcers in the forefoot. Preoperative and postoperative dorsiflexion range of motion of the affected metatarsophalangeal joint and wound-healing data were used to evaluate the effectiveness of the procedure and to determine the relationship between plantar fascia release and ulcer healing. Complications were recorded. Thirty-six (56%) of the ulcers healed within six weeks, including twenty-nine (60%) of the plantar toe ulcers and seven (44%) of the metatarsophalangeal joint ulcers. The mean range of motion of the affected metatarsophalangeal joint increased from 15.3° ± 7.8° to 30.6° ± 14.1° postoperatively (p < 0.05). All patients in whom the preoperative dorsiflexion of the affected metatarsophalangeal joint was between 5° and 30° and in whom the range of motion of that joint increased by ≥13° after the procedure experienced healing of the ulcer. No ulcer recurrence in the original location was identified during follow-up. No patients experienced any complications associated with the selective plantar fascia release. Our results suggest that selective plantar fascia release can lead to healing of neuropathic plantar forefoot ulcers in diabetic patients. Ulcers in patients in whom the preoperative dorsiflexion angle of the affected metatarsophalangeal joint is between 5° and 30° and in whom the increase in range of motion is ≥13° postoperatively have the

  14. Predicting plantar fasciitis in runners.

    PubMed

    Warren, B L; Jones, C J

    1987-02-01

    Ninety-one runners were studied to determine whether specific variables were indicative of runners who had suffered with plantar fasciitis either presently or formerly vs runners who had never suffered with plantar fasciitis. Each runner was asked to complete a running history, was subjected to several anatomical measurements, and was asked to run on a treadmill in both a barefoot and shoe condition at a speed of 3.35 mps (8 min mile pace). Factor coefficients were used in a discriminant function analysis which revealed that, when group membership was predicted, 63% of the runners could be correctly assigned to their group. Considering that 76% of the control group was correctly predicted, it was concluded that the predictor variables were able to correctly predict membership of the control group, but not able to correctly predict the presently or formerly injured sufferers of plantar fasciitis.

  15. Sonoelastography of the plantar fascia.

    PubMed

    Wu, Chueh-Hung; Chang, Ke-Vin; Mio, Sun; Chen, Wen-Shiang; Wang, Tyng-Guey

    2011-05-01

    To compare the stiffness of the plantar fascia by using sonoelastography in healthy subjects of different ages, as well as patients with plantar fasciitis. The study protocol was approved by the Research Ethics Committee of the hospital, and all of the subjects gave their informed consent. Bilateral feet of 40 healthy subjects and 13 subjects with plantar fasciitis (fasciitis group) were examined by using color-coded sonoelastography. Healthy subjects were divided into younger (18-50 years) and older (> 50 years) groups. The color scheme was red (hard), green (medium stiffness), and blue (soft). The color histogram was subsequently analyzed. Each pixel of the image was separated into red, green, and blue components (color intensity range, 0-255). The color histogram then computed the mean intensity of each color component of the pixels within a standardized area. Mixed model for repeated measurements was used for comparison of the plantar fascia thickness and the intensity of the color components on sonoelastogram. Quantitative analysis of the color histogram revealed a significantly greater intensity of blue in older healthy subjects than in younger (94.5 ± 5.6 [± standard deviation] vs 90.0 ± 4.6, P = .002) subjects. The intensity of red and green was the same between younger and older healthy subjects (P = .68 and 0.12). The intensity of red was significantly greater in older healthy subjects than in the fasciitis group (147.8 ± 10.3 vs 133.7 ± 13.4, P < .001). The intensity of green and blue was the same between older healthy subjects and those in the fasciitis group (P = .33 and .71). Sonoelastography revealed that the plantar fascia softens with age and in subjects with plantar fasciitis. RSNA, 2011

  16. Plantar fascia softening in plantar fasciitis with normal B-mode sonography.

    PubMed

    Wu, Chueh-Hung; Chen, Wen-Shiang; Wang, Tyng-Guey

    2015-11-01

    To investigate plantar fascia elasticity in patients with typical clinical manifestations of plantar fasciitis but normal plantar fascia morphology on B-mode sonography. Twenty patients with plantar fasciitis (10 unilateral and 10 bilateral) and 30 healthy volunteers, all with normal plantar fascia morphology on B-mode sonography, were included in the study. Plantar fascia elasticity was evaluated by sonoelastographic examination. All sonoelastograms were quantitatively analyzed, and less red pixel intensity was representative of softer tissue. Pixel intensity was compared among unilateral plantar fasciitis patients, bilateral plantar fasciitis patients, and healthy volunteers by one-way ANOVA. A post hoc Scheffé's test was used to identify where the differences occurred. Compared to healthy participants (red pixel intensity: 146.9 ± 9.1), there was significantly less red pixel intensity in the asymptomatic sides of unilateral plantar fasciitis (140.4 ± 7.3, p = 0.01), symptomatic sides of unilateral plantar fasciitis (127.1 ± 7.4, p < 0.001), and both sides of bilateral plantar fasciitis (129.4 ± 7.5, p < 0.001). There were no significant differences in plantar fascia thickness or green or blue pixel intensity among these groups. Sonoelastography revealed that the plantar fascia is softer in patients with typical clinical manifestations of plantar fasciitis, even if they exhibit no abnormalities on B-mode sonography.

  17. Plantar Fasciitis: Prescribing Effective Treatments.

    ERIC Educational Resources Information Center

    Shea, Michael; Fields, Karl B.

    2002-01-01

    Plantar fasciitis is an extremely common, painful injury seen among people in running and jumping sports. While prognosis for recovery with conservative care is excellent, prolonged duration of symptoms affects sports participation. Studies on treatment options show mixed results, so finding effective treatments can be challenging. A logical…

  18. Can maximal and rapid isometric torque characteristics predict playing level in division I American collegiate football players?

    PubMed

    Thompson, Brennan J; Ryan, Eric D; Sobolewski, Eric J; Smith, Doug B; Conchola, Eric C; Akehi, Kazuma; Buckminster, Tyler

    2013-03-01

    The purpose of this study was to determine if maximal and rapid isometric torque characteristics could discriminate starters from nonstarters in elite Division I American collegiate football players. Sixteen starters (mean ± SD: age = 20.81 ± 1.28 years; height = 184.53 ± 6.58 cm; and mass = 108.69 ± 22.16 kg) and 15 nonstarters (20.40 ± 1.68 years; 182.27 ± 10.52 cm; and 104.60 ± 22.44 kg) performed isometric maximal voluntary contractions (MVCs) of the leg flexor and extensor muscle groups. Peak torque (PT), rate of torque development (RTD), the time to peak RTD (TTRTDpeak), contractile impulse (IMPULSE), and absolute torque values (TORQUE) at specific time intervals were calculated from a torque-time curve. The results indicated significant and nonsignificant differences between starters and nonstarters for the early rapid leg flexion torque characteristics that included RTD, IMPULSE, and TORQUE at 30 and 50 milliseconds, and TTRTDpeak. These variables also demonstrated the largest effect sizes of all the variables examined (0.71-0.82). None of the leg extensor variables, leg flexion PT, or later leg flexion rapid torque variables (≥ 100 milliseconds) were significant discriminators of playing level. These findings suggest that the early rapid leg flexion torque variables may provide an effective and sensitive muscle performance measurement in the identification of collegiate football talent. Further, coaches and practitioners may use these findings when designing training programs for collegiate football players with the intent to maximize rapid leg flexion characteristics.

  19. Isokinetic profile of elbow flexion and extension strength in elite junior tennis players.

    PubMed

    Ellenbecker, Todd S; Roetert, E Paul

    2003-02-01

    Descriptive study. To determine whether bilateral differences exist in concentric elbow flexion and extension strength in elite junior tennis players. The repetitive nature of tennis frequently produces upper extremity overuse injuries. Prior research has identified tennis-specific strength adaptation in the dominant shoulder and distal upper extremity musculature of elite players. No previous study has addressed elbow flexion and extension strength. Thirty-eight elite junior tennis players were bilaterally tested for concentric elbow flexion and extension muscle performance on a Cybex 6000 isokinetic dynamometer at 90 degrees/s, 210 degrees/s, and 300 degrees/s. Repeated-measures ANOVAs were used to test for differences between extremities, muscle groups, and speed. Significantly greater (P<0.002) dominant-arm elbow extension peak torque values were measured at 90 degrees/s, 210 degrees/s, and 300 degrees/s for males. Significantly greater (P<0.002) dominant-arm single-repetition work values were also measured at 90 degrees/s and 210 degrees/s for males. No significant difference was measured between extremities in elbow flexion muscular performance in males and for elbow flexion or extension peak torque and single-repetition work values in females. No significant difference between extremities was measured in elbow flexion/extension strength ratios in females and significant differences between extremities in this ratio were only present at 210 degrees/s in males (P<0.002). These data indicate muscular adaptations around the dominant elbow in male elite junior tennis players but not females. These data have ramifications for clinicians rehabilitating upper extremity injuries in patients from this population.

  20. Reliability of doming and toe flexion testing to quantify foot muscle strength.

    PubMed

    Ridge, Sarah Trager; Myrer, J William; Olsen, Mark T; Jurgensmeier, Kevin; Johnson, A Wayne

    2017-01-01

    Quantifying the strength of the intrinsic foot muscles has been a challenge for clinicians and researchers. The reliable measurement of this strength is important in order to assess weakness, which may contribute to a variety of functional issues in the foot and lower leg, including plantar fasciitis and hallux valgus. This study reports 3 novel methods for measuring foot strength - doming (previously unmeasured), hallux flexion, and flexion of the lesser toes. Twenty-one healthy volunteers performed the strength tests during two testing sessions which occurred one to five days apart. Each participant performed each series of strength tests (doming, hallux flexion, and lesser toe flexion) four times during the first testing session (twice with each of two raters) and two times during the second testing session (once with each rater). Intra-class correlation coefficients were calculated to test for reliability for the following comparisons: between raters during the same testing session on the same day (inter-rater, intra-day, intra-session), between raters on different days (inter-rater, inter-day, inter-session), between days for the same rater (intra-rater, inter-day, inter-session), and between sessions on the same day by the same rater (intra-rater, intra-day, inter-session). ICCs showed good to excellent reliability for all tests between days, raters, and sessions. Average doming strength was 99.96 ± 47.04 N. Average hallux flexion strength was 65.66 ± 24.5 N. Average lateral toe flexion was 50.96 ± 22.54 N. These simple tests using relatively low cost equipment can be used for research or clinical purposes. If repeated testing will be conducted on the same participant, it is suggested that the same researcher or clinician perform the testing each time for optimal reliability.

  1. Design of a lightweight, tethered, torque-controlled knee exoskeleton.

    PubMed

    Witte, Kirby Ann; Fatschel, Andreas M; Collins, Steven H

    2017-07-01

    Lower-limb exoskeletons show promise for improving gait rehabilitation for those with chronic gait abnormalities due to injury, stroke or other illness. We designed and built a tethered knee exoskeleton with a strong lightweight frame and comfortable, four-point contact with the leg. The device is structurally compliant in select directions, instrumented to measure joint angle and applied torque, and is lightweight (0.76 kg). The exoskeleton is actuated by two off-board motors. Closed loop torque control is achieved using classical proportional feedback control with damping injection in conjunction with iterative learning. We tested torque measurement accuracy and found root mean squared (RMS) error of 0.8 Nm with a max load of 62.2 Nm. Bandwidth was measured to be phase limited at 45 Hz when tested on a rigid test stand and 23 Hz when tested on a person's leg. During bandwidth tests peak extension torques were measured up to 50 Nm. Torque tracking was tested during walking on a treadmill at 1.25 m/s with peak flexion torques of 30 Nm. RMS torque tracking error averaged over a hundred steps was 0.91 Nm. We intend to use this knee exoskeleton to investigate robotic assistance strategies to improve gait rehabilitation and enhance human athletic ability.

  2. Effect of eccentric training on the plantar flexor muscle-tendon tissue properties.

    PubMed

    Mahieu, Nele Nathalie; McNair, Peter; Cools, Ann; D'Haen, Caroline; Vandermeulen, Katrien; Witvrouw, Erik

    2008-01-01

    It has been shown that eccentric training can be effective in the rehabilitation of patients with Achilles tendonopathy. The mechanism behind these results is not clear. However, there is evidence that tendons are able to respond to repeated forces by altering their structure and composition, and, thus, their mechanical properties change. In this regard, the objective of the present study was to investigate whether eccentric training affects the mechanical properties of the plantar flexor's muscle-tendon tissue properties. Seventy-four healthy subjects were randomized into two groups: an eccentric training group and a control group. The eccentric training group performed a 6-wk eccentric training program for the calf muscles. Before and after this period, all subjects were evaluated for dorsiflexion range of motion using universal goniometry, passive resistive torque of the plantar flexors, and stiffness of the Achilles tendon. Passive resistive torque was measured during ankle dorsiflexion on an isokinetic dynamometer. Stiffness of the Achilles tendon was assessed using a dynamometer, in combination with ultrasonography. The results of the study reveal that the dorsiflexion range of motion was significantly increased only in the eccentric training group. The eccentric heel drop program also resulted in a significant decrease of the passive resistive torque of the plantar flexors (from 16.423 +/- 0.827 to 12.651 +/- 0.617 N.m). The stiffness of the Achilles tendon did not change significantly as a result of training. These findings provide evidence that an eccentric training program results in changes to some of the mechanical properties of the plantar flexor muscles. These changes were thought to be associated with modifications to structure rather than to stretch tolerance.

  3. Influence of Joint Angle on EMG-Torque Model During Constant-Posture, Torque-Varying Contractions.

    PubMed

    Liu, Pu; Liu, Lukai; Clancy, Edward A

    2015-11-01

    Relating the electromyogram (EMG) to joint torque is useful in various application areas, including prosthesis control, ergonomics and clinical biomechanics. Limited study has related EMG to torque across varied joint angles, particularly when subjects performed force-varying contractions or when optimized modeling methods were utilized. We related the biceps-triceps surface EMG of 22 subjects to elbow torque at six joint angles (spanning 60° to 135°) during constant-posture, torque-varying contractions. Three nonlinear EMG σ -torque models, advanced EMG amplitude (EMG σ ) estimation processors (i.e., whitened, multiple-channel) and the duration of data used to train models were investigated. When EMG-torque models were formed separately for each of the six distinct joint angles, a minimum "gold standard" error of 4.01±1.2% MVC(F90) resulted (i.e., error relative to maximum voluntary contraction at 90° flexion). This model structure, however, did not directly facilitate interpolation across angles. The best model which did so achieved a statistically equivalent error of 4.06±1.2% MVC(F90). Results demonstrated that advanced EMG σ processors lead to improved joint torque estimation as do longer model training durations.

  4. Mechanical and energetic consequences of reduced ankle plantar-flexion in human walking

    PubMed Central

    Huang, Tzu-wei P.; Shorter, Kenneth A.; Adamczyk, Peter G.; Kuo, Arthur D.

    2015-01-01

    ABSTRACT The human ankle produces a large burst of ‘push-off’ mechanical power late in the stance phase of walking, reduction of which leads to considerably poorer energy economy. It is, however, uncertain whether the energetic penalty results from poorer efficiency when the other leg joints substitute for the ankle's push-off work, or from a higher overall demand for work due to some fundamental feature of push-off. Here, we show that greater metabolic energy expenditure is indeed explained by a greater demand for work. This is predicted by a simple model of walking on pendulum-like legs, because proper push-off reduces collision losses from the leading leg. We tested this by experimentally restricting ankle push-off bilaterally in healthy adults (N=8) walking on a treadmill at 1.4 m s−1, using ankle–foot orthoses with steel cables limiting motion. These produced up to ∼50% reduction in ankle push-off power and work, resulting in up to ∼50% greater net metabolic power expenditure to walk at the same speed. For each 1 J reduction in ankle work, we observed 0.6 J more dissipative collision work by the other leg, 1.3 J more positive work from the leg joints overall, and 3.94 J more metabolic energy expended. Loss of ankle push-off required more positive work elsewhere to maintain walking speed; this additional work was performed by the knee, apparently at reasonably high efficiency. Ankle push-off may contribute to walking economy by reducing dissipative collision losses and thus overall work demand. PMID:26385330

  5. Mechanical and energetic consequences of reduced ankle plantar-flexion in human walking.

    PubMed

    Huang, Tzu-wei P; Shorter, Kenneth A; Adamczyk, Peter G; Kuo, Arthur D

    2015-11-01

    The human ankle produces a large burst of 'push-off' mechanical power late in the stance phase of walking, reduction of which leads to considerably poorer energy economy. It is, however, uncertain whether the energetic penalty results from poorer efficiency when the other leg joints substitute for the ankle's push-off work, or from a higher overall demand for work due to some fundamental feature of push-off. Here, we show that greater metabolic energy expenditure is indeed explained by a greater demand for work. This is predicted by a simple model of walking on pendulum-like legs, because proper push-off reduces collision losses from the leading leg. We tested this by experimentally restricting ankle push-off bilaterally in healthy adults (N=8) walking on a treadmill at 1.4 m s(-1), using ankle-foot orthoses with steel cables limiting motion. These produced up to ∼50% reduction in ankle push-off power and work, resulting in up to ∼50% greater net metabolic power expenditure to walk at the same speed. For each 1 J reduction in ankle work, we observed 0.6 J more dissipative collision work by the other leg, 1.3 J more positive work from the leg joints overall, and 3.94 J more metabolic energy expended. Loss of ankle push-off required more positive work elsewhere to maintain walking speed; this additional work was performed by the knee, apparently at reasonably high efficiency. Ankle push-off may contribute to walking economy by reducing dissipative collision losses and thus overall work demand. © 2015. Published by The Company of Biologists Ltd.

  6. Plantar Fascia Rupture: Ultrasound to Facilitate Recognition.

    PubMed

    Servey, Jessica T; Jonas, Christopher

    2018-01-01

    Plantar fascia rupture in the absence of previous diagnosis of plantar fasciitis, corticosteroid injection, or injury is a rare occurrence with only 7 case reports in the literature since 1978. This is a case of spontaneous plantar fascia rupture in a 38-year-old active-duty US military member with current considerations in musculoskeletal ultrasound, other radiologic imaging, treatment, and followup of this diagnosis. © Copyright 2018 by the American Board of Family Medicine.

  7. Getting to the heel of the problem: plantar fascia lesions.

    PubMed

    Jeswani, T; Morlese, J; McNally, E G

    2009-09-01

    Heel pain is a frequent disabling symptom. Clinical diagnosis is often difficult with a large range of possible diagnoses. Lesions of the plantar fascia form an important group. We present a review describing the common lesions of the plantar fascia, including plantar fasciitis, plantar fascia rupture, plantar fibromatosis, and plantar xanthoma, and illustrate them with appropriate magnetic resonance imaging (MRI) and ultrasound imaging. We also address foreign-body reactions, enthesopathy, and diabetic fascial disease.

  8. Angular Acceleration without Torque?

    ERIC Educational Resources Information Center

    Kaufman, Richard D.

    2012-01-01

    Hardly. Just as Robert Johns qualitatively describes angular acceleration by an internal force in his article "Acceleration Without Force?" here we will extend the discussion to consider angular acceleration by an internal torque. As we will see, this internal torque is due to an internal force acting at a distance from an instantaneous center.

  9. Spontaneous distal rupture of the plantar fascia.

    PubMed

    Gitto, Salvatore; Draghi, Ferdinando

    2018-07-01

    Spontaneous ruptures of the plantar fascia are uncommon injuries. They typically occur at its calcaneal insertion and usually represent a complication of plantar fasciitis and local treatment with steroid injections. In contrast, distal ruptures commonly result from traumatic injuries. We describe the case of a spontaneous distal rupture of the plantar fascia in a 48-year-old woman with a low level of physical activity and no history of direct injury to the foot, plantar fasciitis, or steroid injections. © 2017 Wiley Periodicals, Inc.

  10. van der Waals torque

    NASA Astrophysics Data System (ADS)

    Esquivel-Sirvent, Raul; Schatz, George

    2014-03-01

    The theory of generalized van der Waals forces by Lifshtz when applied to optically anisotropic media predicts the existence of a torque. In this work we present a theoretical calculation of the van der Waals torque for two systems. First we consider two isotropic parallel plates where the anisotropy is induced using an external magnetic field. The anisotropy will in turn induce a torque. As a case study we consider III-IV semiconductors such as InSb that can support magneto plasmons. The calculations of the torque are done in the Voigt configuration, that occurs when the magnetic field is parallel to the surface of the slabs. The change in the dielectric function as the magnetic field increases has the effect of decreasing the van der Waals force and increasing the torque. Thus, the external magnetic field is used to tune both the force and torque. The second example we present is the use of the torque in the non retarded regime to align arrays of nano particle slabs. The torque is calculated within Barash and Ginzburg formalism in the nonretarded limit, and is quantified by the introduction of a Hamaker torque constant. Calculations are conducted between anisotropic slabs of materials including BaTiO3 and arrays of Ag nano particles. Depending on the shape and arrangement of the Ag nano particles the effective dielectric function of the array can be tuned as to make it more or less anisotropic. We show how this torque can be used in self assembly of arrays of nano particles. ref. R. Esquivel-Sirvent, G. C. Schatz, Phys. Chem C, 117, 5492 (2013). partial support from DGAPA-UNAM.

  11. Multi-segment foot kinematics and ground reaction forces during gait of individuals with plantar fasciitis.

    PubMed

    Chang, Ryan; Rodrigues, Pedro A; Van Emmerik, Richard E A; Hamill, Joseph

    2014-08-22

    Clinically, plantar fasciitis (PF) is believed to be a result and/or prolonged by overpronation and excessive loading, but there is little biomechanical data to support this assertion. The purpose of this study was to determine the differences between healthy individuals and those with PF in (1) rearfoot motion, (2) medial forefoot motion, (3) first metatarsal phalangeal joint (FMPJ) motion, and (4) ground reaction forces (GRF). We recruited healthy (n=22) and chronic PF individuals (n=22, symptomatic over three months) of similar age, height, weight, and foot shape (p>0.05). Retro-reflective skin markers were fixed according to a multi-segment foot and shank model. Ground reaction forces and three dimensional kinematics of the shank, rearfoot, medial forefoot, and hallux segment were captured as individuals walked at 1.35 ms(-1). Despite similarities in foot anthropometrics, when compared to healthy individuals, individuals with PF exhibited significantly (p<0.05) (1) greater total rearfoot eversion, (2) greater forefoot plantar flexion at initial contact, (3) greater total sagittal plane forefoot motion, (4) greater maximum FMPJ dorsiflexion, and (5) decreased vertical GRF during propulsion. These data suggest that compared to healthy individuals, individuals with PF exhibit significant differences in foot kinematics and kinetics. Consistent with the theoretical injury mechanisms of PF, we found these individuals to have greater total rearfoot eversion and peak FMPJ dorsiflexion, which may put undue loads on the plantar fascia. Meanwhile, increased medial forefoot plantar flexion at initial contact and decreased propulsive GRF are suggestive of compensatory responses, perhaps to manage pain. Copyright © 2014 Elsevier Ltd. All rights reserved.

  12. Are repeated single-limb heel raises and manual muscle testing associated with peak plantar-flexor force in people with inclusion body myositis?

    PubMed

    Harris-Love, Michael O; Shrader, Joseph A; Davenport, Todd E; Joe, Galen; Rakocevic, Goran; McElroy, Beverly; Dalakas, Marinos

    2014-04-01

    Repeated heel raises have been proposed as a method of ankle plantar-flexor strength testing that circumvents the limitations of manual muscle testing (MMT). The study objective was to examine the relationships among ankle plantar-flexion isometric maximum voluntary contraction (MVC), repeated single-limb heel raises (SLHRs), and MMT in people with myositis. This was a cross-sectional study with a between-group design. The ability to complete 1 SLHR determined group assignment (SLHR group, n=24; no-SLHR group, n=19). Forty-three participants with myositis (13 women; median age=64.9 years) participated. Outcome measures included MVC, predicted MVC, Kendall MMT, and Daniels-Worthingham MMT. The Kendall MMT was unable to detect significant ankle plantar-flexor weakness established by quantitative methods and was unable to discriminate between participants who could and those who could not perform the SLHR task. Ankle plantar-flexion MVC was not associated with the number of heel-raise repetitions in the SLHR group (pseudo R(2)=.13). No significant relationship was observed between MVC values and MMT grades in the SLHR and no-SLHR groups. However, a moderate relationship between MVC values and MMT grades was evident in a combined-group analysis (ρ=.50-.67). The lower half of both MMT grading scales was not represented in the study despite the profound weakness of the participants. Both Kendall MMT and Daniels-Worthingham MMT had limited utility in the assessment of ankle plantar-flexor strength. Repeated SLHRs should not be used as a proxy measure of ankle plantar-flexion MVC in people with myositis.

  13. Head flexion angle while using a smartphone.

    PubMed

    Lee, Sojeong; Kang, Hwayeong; Shin, Gwanseob

    2015-01-01

    Repetitive or prolonged head flexion posture while using a smartphone is known as one of risk factors for pain symptoms in the neck. To quantitatively assess the amount and range of head flexion of smartphone users, head forward flexion angle was measured from 18 participants when they were conducing three common smartphone tasks (text messaging, web browsing, video watching) while sitting and standing in a laboratory setting. It was found that participants maintained head flexion of 33-45° (50th percentile angle) from vertical when using the smartphone. The head flexion angle was significantly larger (p < 0.05) for text messaging than for the other tasks, and significantly larger while sitting than while standing. Study results suggest that text messaging, which is one of the most frequently used app categories of smartphone, could be a main contributing factor to the occurrence of neck pain of heavy smartphone users. Practitioner Summary: In this laboratory study, the severity of head flexion of smartphone users was quantitatively evaluated when conducting text messaging, web browsing and video watching while sitting and standing. Study results indicate that text messaging while sitting caused the largest head flexion than that of other task conditions.

  14. Hidden flexion injury of the cervical spine.

    PubMed

    Webb, J K; Broughton, R B; McSweeney, T; Park, W M

    1976-08-01

    This paper describes seven patients who developed late vertebral deformity after flexion injuries of the cervical spine. In four the clinical and radiological features were subtle and because the patients walked into an emergency department the severity of the injury was not initially appreciated. Certain specific clinical and radiological features of flexion injury are described and emphasis is placed on the importance of correct management. A radiological tetrad is described which should alert the surgeon to the possibility of damage to the posterior interspinous complex of the cervical spine and so lead to further radiological investigations. Despite the frequency of flexion injuries the alarming complications described in this paper are rare.

  15. Post-traumatic unilateral plantar hyperhidrosis.

    PubMed

    Eren, Y; Yavasoglu, N G; Comoglu, S S

    2016-02-01

    Localized unilateral hyperhidrosis is rare and poorly understood, sometimes stemming from trauma. Feet, quite vulnerable to trauma are affected by disease-mediated plantar hyperhidrosis, usually bilaterally. This report describes partial hyperhidrosis developing post-traumatically on the left plantar region of a 52-year-old male.

  16. Diagnosis and management of plantar fasciitis.

    PubMed

    Thompson, John V; Saini, Sundeep S; Reb, Christopher W; Daniel, Joseph N

    2014-12-01

    Plantar fasciitis, a chronic degenerative process that causes medial plantar heel pain, is responsible for approximately 1 million physician visits each year. Individuals with plantar fasciitis experience pain that is most intense during their first few steps of the day or after prolonged standing. The authors provide an overview of the diagnosis and management of a common problem encountered in the primary care setting. Routine imaging is not initially recommended for the evaluation of plantar fasciitis but may be required to rule out other pathologic conditions. Overall, plantar fasciitis carries a good prognosis when patients use a combination of several conservative treatment modalities. Occasionally, referral to a specialist may be necessary. © 2014 The American Osteopathic Association.

  17. Targeting the Plantar Fascia for Corticosteroid Injection.

    PubMed

    Salvi, Andrea Emilio

    2015-01-01

    Plantar fasciitis is often a difficult condition to treat. It is related to repetitive strain of the fascia at its attachment to the heel bone. This condition quite often appears with the concomitant presence of a plantar calcaneal heel spur. Corticosteroid injection is a popular treatment choice for plantar fasciitis, and accurate localization of the injected medication is essential for successful resolution of symptoms after the injection. In the present brief technical communication, a method for targeting the attachment of the plantar fascia to the medial tubercle of the tuberosity of the calcaneus is described. The targeting method uses the lateral radiograph of the foot to aid in localization of the proximal attachment of the plantar fascia to the calcaneus. Copyright © 2015 American College of Foot and Ankle Surgeons. Published by Elsevier Inc. All rights reserved.

  18. Pelvic rotation torque during fast-pitch softball hitting under three ball height conditions.

    PubMed

    Iino, Yoichi; Fukushima, Atsushi; Kojima, Takeji

    2014-08-01

    The purpose of this study was to investigate the relevance of hip joint angles to the production of the pelvic rotation torque in fast-pitch softball hitting and to examine the effect of ball height on this production. Thirteen advanced female softball players hit stationary balls at three different heights: high, middle, and low. The pelvic rotation torque, defined as the torque acting on the pelvis through the hip joints about the pelvic superior-inferior axis, was determined from the kinematic and force plate data using inverse dynamics. Irrespective of the ball heights, the rear hip extension, rear hip external rotation, front hip adduction, and front hip flexion torques contributed to the production of pelvic rotation torque. Although the contributions of the adduction and external rotation torques at each hip joint were significantly different among the ball heights, the contributions of the front and rear hip joint torques were similar among the three ball heights owing to cancelation of the two torque components. The timings of the peaks of the hip joint torque components were significantly different, suggesting that softball hitters may need to adjust the timings of the torque exertions fairly precisely to rotate the upper body effectively.

  19. Torque Compensator for Mirror Mountings

    NASA Technical Reports Server (NTRS)

    Howe, S. D.

    1983-01-01

    Device nulls flexural distributions of pivotal torques. Magnetic compensator for flexing pivot torque consists of opposing fixed and movable magnet bars. Magnetic torque varies nonlinearly as function of angle of tilt of movable bar. Positions of fixed magnets changed to improve magnetic torque linearity.

  20. Turbine Windage Torque Tests.

    DTIC Science & Technology

    1981-01-01

    chamber, with a 0-60,000 RPM, 300 HP dynamometer, was selected as the test facility. A rotary transformer ( brushless ) torque sensor, using air /oil... brushless ) of 100 and 500 in-lb torque ranges were selected from Lebow Associates, Inc. of Troy, Michigan. Special air / oil mist lubrication for the...period August 1979 - October 1980 I Approved for public release; distribution unlimited. _ DTIC AERO PROPULSION LABORATORY AIR FORCE WRIGHT AERONAUTICAL

  1. Fabricated torque shaft

    DOEpatents

    Mashey, Thomas Charles

    2002-01-01

    A fabricated torque shaft is provided that features a bolt-together design to allow vane schedule revisions with minimal hardware cost. The bolt-together design further facilitates on-site vane schedule revisions with parts that are comparatively small. The fabricated torque shaft also accommodates stage schedules that are different one from another in non-linear inter-relationships as well as non-linear schedules for a particular stage of vanes.

  2. Biomechanics of the Flexion of Spine.

    ERIC Educational Resources Information Center

    Hobbs, Harry K.; Aurora, T. S.

    1991-01-01

    The forces and torques experienced by the spine are examined to understand, and possibly avoid, low back pain. The structure, degrees of freedom, forces and torques when lifting objects, an experimental study, and other factors affecting the back are discussed. (KR)

  3. Displaceable Gear Torque Controlled Driver

    NASA Technical Reports Server (NTRS)

    Cook, Joseph S., Jr. (Inventor)

    1997-01-01

    Methods and apparatus are provided for a torque driver including a displaceable gear to limit torque transfer to a fastener at a precisely controlled torque limit. A biasing assembly biases a first gear into engagement with a second gear for torque transfer between the first and second gear. The biasing assembly includes a pressurized cylinder controlled at a constant pressure that corresponds to a torque limit. A calibrated gage and valve is used to set the desired torque limit. One or more coiled output linkages connect the first gear with the fastener adaptor which may be a socket for a nut. A gear tooth profile provides a separation force that overcomes the bias to limit torque at the desired torque limit. Multiple fasteners may be rotated simultaneously to a desired torque limit if additional output spur gears are provided. The torque limit is adjustable and may be different for fasteners within the same fastener configuration.

  4. Musculoskeletal modelling deconstructs the paradoxical effects of elastic ankle exoskeletons on plantar-flexor mechanics and energetics during hopping

    PubMed Central

    Farris, Dominic James; Hicks, Jennifer L.; Delp, Scott L.; Sawicki, Gregory S.

    2014-01-01

    Experiments have shown that elastic ankle exoskeletons can be used to reduce ankle joint and plantar-flexor muscle loading when hopping in place and, in turn, reduce metabolic energy consumption. However, recent experimental work has shown that such exoskeletons cause less favourable soleus (SO) muscle–tendon mechanics than is observed during normal hopping, which might limit the capacity of the exoskeleton to reduce energy consumption. To directly link plantar-flexor mechanics and energy consumption when hopping in exoskeletons, we used a musculoskeletal model of the human leg and a model of muscle energetics in simulations of muscle–tendon dynamics during hopping with and without elastic ankle exoskeletons. Simulations were driven by experimental electromyograms, joint kinematics and exoskeleton torque taken from previously published data. The data were from seven males who hopped at 2.5 Hz with and without elastic ankle exoskeletons. The energetics model showed that the total rate of metabolic energy consumption by ankle muscles was not significantly reduced by an ankle exoskeleton. This was despite large reductions in plantar-flexor force production (40–50%). The lack of larger metabolic reductions with exoskeletons was attributed to increases in plantar-flexor muscle fibre velocities and a shift to less favourable muscle fibre lengths during active force production. This limited the capacity for plantar-flexors to reduce activation and energy consumption when hopping with exoskeleton assistance. PMID:25278469

  5. Manual therapy for plantar heel pain.

    PubMed

    Pollack, Yosefa; Shashua, Anat; Kalichman, Leonid

    2018-03-01

    Manual therapy employed in the treatment of plantar heel pain includes joint or soft tissue mobilizations. Efficacy of these methods is still under debate. To determine whether manual therapy, consisting of deep massage, myofascial release or joint mobilization is effective in treating plantar heel pain. A critical review of all available studies with an emphasis on randomized controlled trials (RCTs) was performed. PubMed, PEDro, and Google Scholar databases were searched for keywords relating to plantar heel pain, joint, and soft tissue mobilizations. There were no search limitations or language restrictions. The reference lists of all retrieved articles were searched. The PEDro score was used to assess the quality of the reviewed papers. A total of six relevant RCTs were found: two examined the effectiveness of joint mobilization on plantar heel pain and four the effectiveness of soft tissue techniques. Five studies showed a positive short-term effect after manual therapy treatment, mostly soft tissue mobilizations, with or without stretching exercises for patients with plantar heel pain, compared to other treatments. One study observed that adding joint mobilization to the treatment of plantar heel pain was not effective. The quality of all studies was moderate to high. According to reviewed moderate and high-quality RCTs, soft tissue mobilization is an effective modality for treating plantar heel pain. Outcomes of joint mobilizations are controversial. Further studies are needed to evaluate the short and long-term effect of different soft tissue mobilization techniques. Copyright © 2017 Elsevier Ltd. All rights reserved.

  6. Human torque velocity adaptations to sprint, endurance, or combined modes of training

    NASA Technical Reports Server (NTRS)

    Shealy, M. J.; Callister, R.; Dudley, G. A.; Fleck, S. J.

    1992-01-01

    We had groups of athletes perform sprint and endurance run training independently or concurrently for 8 weeks to examine the voluntary in vivo mechanical responses to each type of training. Pre- and posttraining angle-specific peak torque during knee extension and flexion were determined at 0, 0.84, 1.65, 2.51, 3.35, 4.19, and 5.03 radian.sec-1 and normalized for lean body mass. Knee extension torque in the sprint-trained group increased across all test velocities, the endurance-trained group increased at 2.51, 3.34, 4.19, and 5.03 radian.sec-1, and the group performing the combined training showed no change at any velocity. Knee flexion torque of the sprint and combined groups decreased at 0.84, 1.65, and 2.51 radian.sec-1. Knee flexion torque in the sprint-trained group also decreased at 0 radian.sec-1 and in the combined group at 3.34 radian.sec-1. Knee flexion torque in the endurance-trained group showed no change at any velocity of contraction. Mean knee flexion:extension ratios across the test velocities significantly decreased in the sprint-trained group. Knee extension endurance during 30 seconds of maximal contractions significantly increased in all groups. Only the sprint-trained group showed a significant increase in endurance of the knee flexors. These data suggest that changes in the voluntary in vivo mechanical characteristics of knee extensor and flexor skeletal muscles are specific to the type of run training performed.

  7. Effects of hamstring stretching on passive muscle stiffness vary between hip flexion and knee extension maneuvers.

    PubMed

    Miyamoto, N; Hirata, K; Kanehisa, H

    2017-01-01

    The purpose of this study was to examine whether the effects of hamstring stretching on the passive stiffness of each of the long head of the biceps femoris (BFl), semitendinosus (ST), and semimembranosus (SM) vary between passive knee extension and hip flexion stretching maneuvers. In 12 male subjects, before and after five sets of 90 s static stretching, passive lengthening measurements where knee or hip joint was passively rotated to the maximal range of motion (ROM) were performed. During the passive lengthening, shear modulus of each muscle was measured by ultrasound shear wave elastography. Both stretching maneuvers significantly increased maximal ROM and decreased passive torque at a given joint angle. Passive knee extension stretching maneuver significantly reduced shear modulus at a given knee joint angle in all of BFl, ST, and SM. In contrast, the stretching effect by passive hip flexion maneuver was significant only in ST and SM. The present findings indicate that the effects of hamstring stretching on individual passive muscles' stiffness vary between passive knee extension and hip flexion stretching maneuvers. In terms of reducing the muscle stiffness of BFl, stretching of the hamstring should be performed by passive knee extension rather than hip flexion. © 2015 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

  8. Timing of intermittent torque control with wire-driven gait training robot lifting toe trajectory for trip avoidance.

    PubMed

    Miyake, Tamon; Kobayashi, Yo; Fujie, Masakatsu G; Sugano, Shigeki

    2017-07-01

    Gait training robots are useful for changing gait patterns and decreasing risk of trip. Previous research has reported that decreasing duration of the assistance or guidance of the robot is beneficial for efficient gait training. Although robotic intermittent control method for assisting joint motion has been established, the effect of the robot intervention timing on change of toe clearance is unclear. In this paper, we tested different timings of applying torque to the knee, employing the intermittent control of a gait training robot to increase toe clearance throughout the swing phase. We focused on knee flexion motion and designed a gait training robot that can apply flexion torque to the knee with a wire-driven system. We used a method of timing detecting for the robot conducting torque control based on information from the hip, knee, and ankle angles to establish a non-time dependent parameter that can be used to adapt to gait change, such as gait speed. We carried out an experiment in which the conditions were four time points: starting the swing phase, lifting the foot, maintaining knee flexion, and finishing knee flexion. The results show that applying flexion torque to the knee at the time point when people start lifting their toe is effective for increasing toe clearance in the whole swing phase.

  9. Plantar flaps based on perforators of the plantar metatarsal/common digital arteries.

    PubMed

    Valentin, Georgescu Alexandru; Rodica, Matei Ileana; Manuel, Llusa

    2014-09-01

    Because of the unique characteristics of its integument, the affirmation "replacing like with like" becomes more than evident in the reconstruction of defects of the ultraspecialized plantar skin. But, the paucity of local resources, and especially in the forefoot, transforms this attempt in a very challenging problem. Many techniques, including skin grafts and various types of flaps were used in the management of defects in the forefoot. We present a new useful flap in the reconstruction of skin defects in the forefoot, based on small perforator vessels originating either from the plantar metatarsal arteries or plantar common digital arteries. Starting with June 2011, this flap was performed, as plantar transposition perforator flap, plantar propeller flap, or plantar propeller perforator plus flap, in seven patients with ulcers over the plantar forefoot. During a follow-up of 7 to 17 months (mean, 9.8 months), the local evolution regarding flap integration, pain, relapse, sensitive recovery, donor site, and footwear quality was analyzed. We registered a 100% survival rate of the flaps, with delayed healing in only one case. The gait resumption was possible after 6 weeks in all cases. This new flap, based on small perforator vessels from the plantar metatarsal or common digital arteries, and which provides a good, stable, and sensory recovery, seems to be a promising method in the reconstruction of plantar skin defects over the metatarsal heads. Thieme Medical Publishers 333 Seventh Avenue, New York, NY 10001, USA.

  10. The correlation between plantar fascia thickness and symptoms of plantar fasciitis.

    PubMed

    Mahowald, Sarah; Legge, Bradford S; Grady, John F

    2011-01-01

    The purpose of this study was to determine whether changes in plantar fascia thickness are a reliable gauge of efficacy of treatment protocols for plantar fasciitis. Thirty-nine feet (30 patients) with plantar fasciitis received an ultrasound examination to measure the thickness of the medial band of the plantar fascia. Each patient assessed his or her pain using the visual analogue scale. Following various treatments, a second ultrasound examination was performed and the thickness of the plantar fascia was again measured and subjective pain level assessed. Twenty-nine feet (74.4%) showed a decrease in plantar fascia thickness and a decrease in pain. One foot (2.6%) experienced an increase in fascia thickness and reported an increase in pain. Four feet (10.3%) had an increase in thickness of the plantar fascia and reported no change in pain level. Three feet had minor increases in fascia thickness but reported a decrease in pain (7.7%). One foot (2.6%) had no change in fascia thickness but a decrease in pain and one foot (2.6%) had a decrease in the plantar fascia but no change in pain level. The average reduction in fascia thickness was 0.82 mm ± 1.04 mm, correlating with an average improvement in pain of 3.64 ± 2.7 (P < 0.005). This study provides evidence that changing thickness of the plantar fascia is a valid objective measurement to assess effectiveness of new or existing treatment protocols.

  11. Ironless armature torque motor

    NASA Technical Reports Server (NTRS)

    Fisher, R. L.

    1972-01-01

    Four iron-less armature torque motors, four Hall device position sensor assemblies, and two test fixtures were fabricated. The design approach utilized samarium cobalt permanent magnets, a large airgap, and a three-phase winding in a stationary ironless armature. Hall devices were employed to sense rotor position. An ironless armature torque motor having an outer diameter of 4.25 inches was developed to produce a torque constant of 65 ounce-inches per ampere with a resistance of 20.5 ohms. The total weight, including structural elements, was 1.58 pounds. Test results indicated that all specifications were met except for generated voltage waveform. It is recommended that investigations be made concerning the generated voltage waveform to determine if it may be improved.

  12. Power tong torque control

    SciTech Connect

    Buck, D.A.; James, R.N.

    1987-10-20

    Torque controlled powered pipe tongs, are described the apparatus comprises: (a) a power tong powered by a fluid motor; (b) a fluid power source connected to the motor; (c) a force conducting element attached to the power tong, situated to oppose reaction torque from the tongs when torque is applied to pipe; (d) force sensing means operatively associated with the force conducting element situated to sense at least part of the force experienced by the force conducting element, arranged to produce a pressure signal proportional to force sensed; and (e) a fluid by-pass valve, adjustably biased toward a closed position,more » responsive to the signal to tend to move toward an open position, the by-pass valve connected between the fluid power source and the motor.« less

  13. Explosive sport training and torque kinetics in children.

    PubMed

    Dotan, Raffy; Mitchell, Cameron J; Cohen, Rotem; Gabriel, David; Klentrou, Panagiota; Falk, Bareket

    2013-07-01

    A high rate of force development (RFD) is often more important than maximal force in daily and sports activities. In children, resistance training has been shown to increase maximal force. It is unclear whether, or to what extent, can children improve RFD and force kinetics. For this study, we compared strength and force kinetics of boy gymnasts with those of untrained boys and untrained men. Eight boy gymnasts (age, 9.5 ± 1.2 y), 20 untrained boys (age, 10.1 ± 1.3 y), and 20 untrained men (age, 22.9 ± 4.4 y) performed maximal, explosive, isometric elbow flexions (EF) and knee flexions (KF). Peak torque (maximal voluntary contraction (MVC)), elapsed times to 10%-100% MVC, peak rate of torque development (RTDpk), and other kinetics parameters were determined. When gymnasts were compared with untrained boys, size-normalized EF MVC was 11%-20% higher, RTDpk was 32% higher, and times to 30% and 80% MVC were 16% and 55% shorter, respectively (p < 0.05). No corresponding differences were observed in KF. Furthermore, although the normalized EF MVC was 28% lower in gymnasts than in men (p < 0.001), their torque kinetics parameters were similar. These findings highlight the specificity of gymnastics training, which markedly elevated the torque kinetics of young, prepubertal boys to adult levels, but only moderately affected peak torque. It is suggested that neurologic adaptations, such as enhanced firing and activation rates or increased type II motor-unit recruitment, as well as changes in musculotendinous stiffness, could explain these findings.

  14. Foot Plantar Pressure Measurement System: A Review

    PubMed Central

    Razak, Abdul Hadi Abdul; Zayegh, Aladin; Begg, Rezaul K.; Wahab, Yufridin

    2012-01-01

    Foot plantar pressure is the pressure field that acts between the foot and the support surface during everyday locomotor activities. Information derived from such pressure measures is important in gait and posture research for diagnosing lower limb problems, footwear design, sport biomechanics, injury prevention and other applications. This paper reviews foot plantar sensors characteristics as reported in the literature in addition to foot plantar pressure measurement systems applied to a variety of research problems. Strengths and limitations of current systems are discussed and a wireless foot plantar pressure system is proposed suitable for measuring high pressure distributions under the foot with high accuracy and reliability. The novel system is based on highly linear pressure sensors with no hysteresis. PMID:23012576

  15. Active Flexion in Weight Bearing Better Correlates with Functional Outcomes of Total Knee Arthroplasty than Passive Flexion.

    PubMed

    Song, Young Dong; Jain, Nimash; Kang, Yeon Gwi; Kim, Tae Yune; Kim, Tae Kyun

    2016-06-01

    Correlations between maximum flexion and functional outcomes in total knee arthroplasty (TKA) patients are reportedly weak. We investigated whether there are differences between passive maximum flexion in nonweight bearing and other types of maximum flexion and whether the type of maximum flexion correlates with functional outcomes. A total of 210 patients (359 knees) underwent preoperative evaluation and postoperative follow-up evaluations (6, 12, and 24 months) for the assessment of clinical outcomes including maximum knee flexion. Maximum flexion was measured under five conditions: passive nonweight bearing, passive weight bearing, active nonweight bearing, and active weight bearing with or without arm support. Data were analyzed for relationships between passive maximum flexion in nonweight bearing by Pearson correlation analyses, and a variance comparison between measurement techniques via paired t test. We observed substantial differences between passive maximum flexion in nonweight bearing and the other four maximum flexion types. At all time points, passive maximum flexion in nonweight bearing correlated poorly with active maximum flexion in weight bearing with or without arm support. Active maximum flexion in weight bearing better correlated with functional outcomes than the other maximum flexion types. Our study suggests active maximum flexion in weight bearing should be reported together with passive maximum flexion in nonweight bearing in research on the knee motion arc after TKA.

  16. Active Flexion in Weight Bearing Better Correlates with Functional Outcomes of Total Knee Arthroplasty than Passive Flexion

    PubMed Central

    Song, Young Dong; Jain, Nimash; Kang, Yeon Gwi; Kim, Tae Yune

    2016-01-01

    Purpose Correlations between maximum flexion and functional outcomes in total knee arthroplasty (TKA) patients are reportedly weak. We investigated whether there are differences between passive maximum flexion in nonweight bearing and other types of maximum flexion and whether the type of maximum flexion correlates with functional outcomes. Materials and Methods A total of 210 patients (359 knees) underwent preoperative evaluation and postoperative follow-up evaluations (6, 12, and 24 months) for the assessment of clinical outcomes including maximum knee flexion. Maximum flexion was measured under five conditions: passive nonweight bearing, passive weight bearing, active nonweight bearing, and active weight bearing with or without arm support. Data were analyzed for relationships between passive maximum flexion in nonweight bearing by Pearson correlation analyses, and a variance comparison between measurement techniques via paired t test. Results We observed substantial differences between passive maximum flexion in nonweight bearing and the other four maximum flexion types. At all time points, passive maximum flexion in nonweight bearing correlated poorly with active maximum flexion in weight bearing with or without arm support. Active maximum flexion in weight bearing better correlated with functional outcomes than the other maximum flexion types. Conclusions Our study suggests active maximum flexion in weight bearing should be reported together with passive maximum flexion in nonweight bearing in research on the knee motion arc after TKA. PMID:27274468

  17. Metatarsophalangeal joint extension changes ultrasound measurements for plantar fascia thickness.

    PubMed

    Granado, Michael J; Lohman, Everett B; Gordon, Keith E; Daher, Noha S

    2018-01-01

    Ultrasound is an inexpensive method for quantifying plantar fascia thickness, especially in those with plantar fasciitis. Ultrasound has also been used to assess the effectiveness of various treatments for plantar fasciitis by comparing plantar fascia thickness before and after an intervention period. While a plantar fascia thickness over 4 mm via ultrasound has been proposed to be consistent with plantar fasciitis, some researchers believe the 4 mm plantar fascia thickness level to be a dubious guideline for diagnosing plantar fasciitis due to the lack of standardization of the measurement process for plantar fascia thickness. In particular, no universal guidelines exist on the positioning of the metatarsophalangeal (MTP) joints during the procedure and the literature also has inconsistent protocols. The purpose of this study is to investigate and compare the influence of MTP joint extension on plantar fascia thickness in healthy participants and those with unilateral plantar fasciitis. The plantar fascia thickness of forty participants (20 with unilateral plantar fasciitis and 20 control) was measured via ultrasound three times at three different MTP joint positions: 1) at rest, 2) 30° of extension from the plantar surface, and 3) maximal extension possible. The plantar fascia became significantly thinner as MTP joint extension increased in both the plantar fasciitis group ( p  < 0.001) and the control group ( p  < 0.001). In the plantar fasciitis group, the involved plantar fascia was 1.2 to 1.3 mm thicker (p < 0.001) than the uninvolved side depending on the MTP joint position. In the control group, the difference in plantar fascia thickness between the two sides was less than 0.1 mm ( p  < 0.92) at any MTP joint position. MTP joint position can influence the ultrasound measurement of plantar fascia thickness. It is recommended that plantar fascia thickness measurements be performed with the toes at rest. If MTP joints must be extended

  18. Torque, Cognitive Ability, and Schooling.

    ERIC Educational Resources Information Center

    Csapo, Marg

    1985-01-01

    West African Hausan Children (N=110) aged 5-6 were administered a torque test and relationshps between the torque task and visual spatial tasks were analyzed. Findings supported the assumption that educational experience related to circling accounts for decrease in torque, or that the educational experiences have potential influence on cortical…

  19. Measuring Gravitational Flexion in ACS Clusters

    NASA Astrophysics Data System (ADS)

    Goldberg, David

    2005-07-01

    We propose measurement of the gravitational "Flexion" signal in ACS cluster images. The flexion, or "arciness" of a lensed background galaxy arises from variations in the lensing field. As a result, it is extremely sensitive to small scale perturbations in the field, and thus, to substructure in clusters. Moreover, because flexion represents gravitationally induced asymmetries in the lensed image, it is completely separable from traditional measurements of shear, which focus on the induced ellipticity of the image, and thus, the two signals may be extracted simultaneously. Since typical galaxies are roughly symmetric upon 180 degree rotation, even a small induced flexion can potentially produce a noticeable effect {Goldberg & Bacon, 2005}. We propose the measurement of substructure within approximately 4 clusters with high-quality ACS data, and will further apply a test of a new tomographic technique whereby comparisons of lensed arcs at different redshifts may be used to estimate the background cosmology, and thus place constraints on the equation of state of dark energy.

  20. Voluntary muscle activation and evoked volitional-wave responses as a function of torque.

    PubMed

    Hight, Robert E; Quarshie, Alwyn T; Black, Christopher D

    2018-08-01

    This study employed a unique stimulation paradigm which allowed for the simultaneous assessment of voluntary activation levels (VA) via twitch-interpolation, and the evoked V-wave responses of the plantar flexors during submaximal and maximal contractions. Test-retest reliability was also examined. Fourteen participants repeated a stimulation protocol over four visits to assess VA and evoked V-wave amplitude across torque levels ranging from 20% to 100% MVC. MVC torque and EMG amplitude were also measured. VA increased nonlinearly with torque production and plateaued by 80% MVC. V-wave amplitude increased linearly from 20% to 100% MVC. There were no differences in any dependent variable across visits (p > 0.05). VA demonstrated moderate to substantial reliability across all torque levels (ICC = 0.76-0.91) while V-wave amplitude exhibited fair to moderate reliability from 40% to 100% (ICC = 0.48-0.74). We were able to reliably collect VA and the V-wave simultaneously in the plantar flexors. Collection of VA and V-wave during the same contraction provides distinct information regarding the contribution of motor-unit recruitment and descending cortico-spinal drive/excitability to force production. Copyright © 2018 Elsevier Ltd. All rights reserved.

  1. Relationship and Classification of Plantar Heel Spurs in Patients With Plantar Fasciitis.

    PubMed

    Ahmad, Jamal; Karim, Ammar; Daniel, Joseph N

    2016-09-01

    This study classified plantar heel spurs and their relationship to plantar fasciitis. Patients included those with plantar fasciitis who were treated from 2012 through 2013. Plantar heel spur shape and size were assessed radiographically and correlated to function and pain before and after treatment. Function and pain were scored with the Foot and Ankle Ability Measures and a visual analog scale, respectively. This study included 109 patients with plantar fasciitis. The plantar heel spur shape was classified as 0/absent in 26 patients, 1/horizontal in 66 patients, 2/vertical in 4 patients, and 3/hooked in 13 patients. The plantar heel spur size was less than 5 mm in 75 patients, 5-10 mm in 28 patients, and greater than 10 mm in 6 patients. Initially, patients with any shape or size to their spur had no difference in function and pain. With treatment, patients with horizontal and hooked spurs had the greatest improvement in function and pain (P < .05). With treatment, patients with larger spurs had the greatest improvement in function and pain (P < .05). Plantar heel spurs can be classified by shape and size in patients with plantar fasciitis. Before treatment, neither the spur shape nor size significantly correlated with symptoms. After treatment, patients with larger horizontal or hooked spurs had the greatest improvement in function and pain. These findings may be important when educating patients about the role of heel spurs with plantar fasciitis and the effect of nonsurgical treatment with certain spurs. Level III, comparative series. © The Author(s) 2016.

  2. Relation between peak knee flexion angle and knee ankle kinetics in single-leg jump landing from running: a pilot study on male handball players to prevent ACL injury.

    PubMed

    Ameer, Mariam A; Muaidi, Qassim I

    2017-09-01

    The relationship between knee kinematics and knee-ankle kinetics during the landing phase of single leg jumping has been widely studied to identify proper strategies for preventing non-contact ACL injury. However, there is a lack of study on knee-ankle kinetics at peak knee flexion angle during jumping from running. Hence, the purpose of this study is to establish the relationship between peak knee flexion angle, knee extension moment, ankle plantar flexion moment and ground reaction force in handball players in order to protect ACL from excessive stress during single leg jumping. In addition, the study also clarifies the role of calf muscles in relieving part of ACL stresses with different knee flexion angles during landing. Fifteen active male elite handball players of Saudi Arabia have participated in this study (Age = 22.6 ± 3.5years, Height = 182 ± 3.7 cm, Weight = 87.5 ± 10.2 kg). The players performed three successful landings of single-leg jump following running a fixed distance of about 450cm. The data were collected using a 3D motion capture and analysis system (VICON). Pearson product moment correlation coefficients showed that greater peak knee flexion angle is related significantly to both lesser knee extension moment (r = -.623, P = .013) and vertical component of ground reaction force (VGRF) (r = -.688, P = .005) in landing phase. Moreover, increasing the peak knee flexion angle in landing phase tends to increase the ankle plantar flexion moment significantly (r = .832, P = .000). With an increase of the peak knee flexion angle during single leg jump landing from running, there would be less knee extension moment, low impact force and more plantar flexion moment. As such, the clinical implication of this study is that there may be a possible protective mechanism by increasing the knee flexion angle during landing phase, which tends to protect the ACL from vigorous strain and injuries.

  3. Hex ball torque test

    NASA Technical Reports Server (NTRS)

    Robinson, B. A.; Foster, C. L.

    1986-01-01

    A series of torque tests were performed on four flight-type hex ball universal joints in order to characterize and determine the actual load-carrying capability of this device. The universal joint is a part of manual actuation rods for scientific instruments within the Hubble Space Telescope. It was found that the hex ball will bind slightly during the initial load application. This binding did not affect the function of the universal joint, and the units would wear-in after a few additional loading cycles. The torsional yield load was approximately 50 ft-lb, and was consistent among the four test specimens. Also, the torque required to cause complete failure exceeded 80 ft-lb. It is concluded that the hex ball universal joint is suitable for its intended applications.

  4. Accuracy of dental torque wrenches.

    PubMed

    Wood, James S; Marlow, Nicole M; Cayouette, Monica J

    2015-01-01

    The aim of this in vitro study was to compare the actual torque of 2 manual wrench systems to their stated (target) torque. New spring- (Nobel Biocare USA, LLC) and friction-style (Zimmer Dental, Inc.) manual dental torque wrenches, as well as spring torque wrenches that had undergone sterilization and clinical use, were tested. A calibrated torque gauge was used to compare actual torque to target torque values of 15 and 35 N/cm. Data were statistically analyzed via mixed-effects regression model with Bonferroni correction. At a target torque of 15 N/cm, the mean torque of new spring wrenches (13.97 N/cm; SE, 0.07 N/cm) was significantly different from that of used spring wrenches (14.94 N/cm; SE, 0.06 N/cm; P < 0.0001). However, the mean torques of new spring and new friction wrenches (14.10 N/cm; SE, 0.07 N/cm; P = 0.21) were not significantly different. For torque measurements calibrated at 35 N/cm, the mean torque of new spring wrenches (35.29 N/cm; SE, 0.10 N/cm) was significantly different (P < 0.0001) from the means of new friction wrenches (36.20 N/cm; SE, 0.08 N/cm) and used spring wrenches (36.45 N/cm; SE, 0.08 N/cm). Discrepancies in torque could impact the clinical success of screw-retained dental implants. It is recommended that torque wrenches be checked regularly to ensure that they are performing to target values.

  5. Platelet-rich plasma and plantar fasciitis.

    PubMed

    Monto, Raymond R

    2013-12-01

    Plantar fasciitis is the most common cause of heel pain and can prove difficult to treat in its most chronic and severe forms. Advanced cases of plantar fasciitis are often associated with ankle stiffness, heel spurs, and other conditions and can lead to extensive physical disability and financial loss. Most available traditional treatments, including orthoses, nonsteroidal anti-inflammatory drugs, and steroid injections have a paucity of supportive clinical evidence. More invasive treatments, ranging from corticosteroid and botulinum-A toxin injections to shockwave therapy and plantar fasciotomy, have demonstrated varying clinical success in severe cases but carry the potential for serious complication and permanent disability. Platelet-rich plasma has recently been demonstrated to be helpful in managing chronic severe tendinopathies when other techniques have failed. This review examines the pathophysiology, diagnostic options, nonoperative treatment modalities, and surgical options currently used for plantar fasciitis. It also focuses on the clinical rationale and available evidence for using autologous platelet-rich plasma to treat severe refractory chronic plantar fasciitis.

  6. Surgery for Patients With Recalcitrant Plantar Fasciitis

    PubMed Central

    Wheeler, Patrick; Boyd, Kevin; Shipton, Mary

    2014-01-01

    Background: Plantar fasciitis is a common cause of foot pain, and although many episodes are self-limiting with short duration, 10% leave chronic symptoms. Recalcitrant cases can be managed surgically, with studies demonstrating good results in the short term but uncertainties over longer term outcomes. Purpose: To assess the outcome following surgical intervention for patients with plantar fasciitis. Study Design: Case series; Level of evidence, 4. Methods: Seventy-nine patients were identified from operative diaries undergoing plantar fasciotomy surgery between 1993 and 2009. They were contacted to investigate long-term results using self-reported outcome measures. Results: Sixty-eight responses were received (86% response rate), with an average of 7 years (range, 1-15 years) of follow-up. Patients reported an average reduction in pain by visual analog scale of 79%, and 84% of patients were happy with the surgical results. Greater success was achieved in patients with shorter duration of symptoms preoperatively. No deterioration in success was seen over time. Conclusion: Plantar fasciotomy surgery for plantar fasciitis remains controversial, with biomechanical arguments against surgery; however, this article reports good success following surgery over a long follow-up period. The results of current operative techniques need to be fully investigated for longer term success, as do the outcomes of newer nonoperative management strategies. PMID:26535314

  7. Knee extension torque variability after exercise in ACL reconstructed knees.

    PubMed

    Goetschius, John; Kuenze, Christopher M; Hart, Joseph M

    2015-08-01

    The purpose of this study was to compare knee extension torque variability in patients with ACL reconstructed knees before and after exercise. Thirty two patients with an ACL reconstructed knee (ACL-R group) and 32 healthy controls (control group) completed measures of maximal isometric knee extension torque (90° flexion) at baseline and following a 30-min exercise protocol (post-exercise). Exercise included 30-min of repeated cycles of inclined treadmill walking and hopping tasks. Dependent variables were the coefficient of variation (CV) and raw-change in CV (ΔCV): CV = (torque standard deviation/torque mean x 100), ΔCV = (post-exercise - baseline). There was a group-by-time interaction (p = 0.03) on CV. The ACL-R group demonstrated greater CV than the control group at baseline (ACL-R = 1.07 ± 0.55, control = 0.79 ± 0.42, p = 0.03) and post-exercise (ACL-R = 1.60 ± 0.91, control = 0.94 ± 0.41, p = 0.001). ΔCV was greater (p = 0.03) in the ACL-R group (0.52 ± 0.82) than control group (0.15 ± 0.46). CV significantly increased from baseline to post-exercise (p = 0.001) in the ACL-R group, while the control group did not (p = 0.06). The ACL-R group demonstrated greater knee extension torque variability than the control group. Exercise increased torque variability more in the ACL-R group than control group. © 2015 Orthopaedic Research Society. Published by Wiley Periodicals, Inc.

  8. Lateral plantar nerve release with or without calcaneal drilling for resistant plantar fasciitis.

    PubMed

    Sadek, Ahmed Fathy; Fouly, Ezzat Hassan; Elian, Mostafa Mohammed

    2015-08-01

    To compare the outcome following lateral plantar nerve release with or without calcaneal drilling for resistant plantar fasciitis. 30 women and 3 men aged 30 to 60 (mean, 45) years with resistant plantar fasciitis were randomised to undergo release of the first branch of the lateral plantar nerve with (group 1, n=18) or without (group 2, n=15) calcaneal drilling. Patients were followed up for a mean of 27 months. According to the modified Mayo scoring system for plantar fasciotomy, group 1 was superior to group 2 in terms of score (93.9±6.97 vs. 83±8.2, p<0.001) and grading (15 excellent, 2 good, and one fair vs. 6 excellent, 4 good, and 5 fair; p=0.031). Three patients in group one and one patient in group 2 (16.7% vs. 6.6%, p=0.381) developed complications of heel numbness, foot oedema, and 2 cases of superficial wound infection, respectively. Adding calcaneal drilling to release of the first branch of the lateral plantar nerve achieves better outcome than release alone in patients with resistant plantar fasciitis.

  9. Endoscopic Plantar Fasciotomy Through Two Medial Portals for the Treatment of Recalcitrant Plantar Fasciopathy.

    PubMed

    Al-Ashhab, Mohamed Ebrahim; Elbegawy, Hossam El-Dein A; Hasan, Hala Ali Abed

    Plantar fasciopathy is a common cause of heel pain. Endoscopic plantar fasciotomy has the advantage of less surgical trauma and rapid recovery. The aim of the present prospective study was to delineate the results of endoscopic plantar fascia release through 2 medial portals. The present study included 2 groups. The first group included 27 feet in 25 patients that had undergone endoscopic plantar fascia release followed up for 19.7 (range 12 to 33) months. The second group, the control group, included 20 feet in 16 patients treated conservatively and followed up for 16.4 (range 12 to 24) months. The results of endoscopic plantar fascia release were superior to the conservative methods. The surgically treated group experienced significantly less pain, activity limitations, and gait abnormality. The presence of a calcaneal spur had no effect on the final postoperative score. In conclusion, endoscopic plantar fascia release through 2 medial portals is an effective procedure for treatment of resistant plantar fasciopathy that fails to respond to conservative management options. Copyright © 2017 The American College of Foot and Ankle Surgeons. Published by Elsevier Inc. All rights reserved.

  10. Does the thickening of Achilles tendon and plantar fascia contribute to the alteration of diabetic foot loading?

    PubMed

    Giacomozzi, C; D'Ambrogi, E; Uccioli, L; Macellari, V

    2005-06-01

    The diabetic foot often undergoes abnormal plantar pressures, changing in walking strategy, ulcerative processes. The present study focuses on the effects that diabetes-induced alterations of Achilles tendon, plantar fascia and first metatarso-phalangeal joint-both anatomical and functional-may have on foot loading. Sixty-one diabetic patients, with or without neuropathy, and 21 healthy volunteers were recruited. Thickness of Achilles tendon and plantar fascia was measured by ultrasound. Flexion-extension of the first metatarso-phalangeal joint was measured passively. Main biomechanic parameters of foot-floor interaction during gait were acquired and related to the above measurements. Plantar fascia and Achilles tendon were significantly (P<0.05) thicker in diabetics than in controls; mean values (SD) for controls, diabetics without and with neuropathy were 2.0 mm (0.5), 2.9 mm (1.2) and 3.0 mm (0.8) for plantar fascia, respectively, and 4.0 mm (0.5), 4.6 mm (1.0) and 4.9 mm (1.7) for Achilles tendon, respectively. Flexion-extension of the first metatarso-phalangeal joint was significantly (P<0.05) smaller in diabetics than in controls; mean values (SD) for controls, diabetics without and with neuropathy were 100.0 degrees (10.0), 54.0 degrees (29.4) and 54.9 degrees (17.2), respectively. The increase in the vertical force under the metatarsals was strongly related (R=0.83, explained variance=70.1%) to the changes in the three above parameters. Thickening of plantar fascia and Achilles tendon in diabetics, more evident in the presence of neuropathy, concurs to develop a rigid foot, which poorly absorbs shock during landing (performs the physiological impact force absorption during landing). More generally, an overall alteration of the foot-ankle complex motion likely occurs throughout the whole gait cycle, which partly explains the abnormal loading under the forefoot.

  11. Lumbopelvic motion during seated hip flexion in subjects with low-back pain accompanying limited hip flexion.

    PubMed

    Kim, Si-hyun; Kwon, Oh-yun; Yi, Chung-hwi; Cynn, Heon-seock; Ha, Sung-min; Park, Kyue-nam

    2014-01-01

    Limited hip flexion may lead to a poor lumbopelvic motion during seated active hip flexion in people with low-back pain (LBP). The purpose of this study was to compare lumbopelvic motion during seated hip flexion between subjects with and without LBP accompanying limited hip flexion. Fifteen patients with LBP accompanying limited hip flexion and 16 healthy subjects were recruited. The subjects performed seated hip flexion with the dominant leg three times. A three-dimensional motion-analysis system was used to measure lumbopelvic motion during seated hip flexion. During seated active hip flexion, the angle of hip flexion was significantly lower in patients with LBP accompanying limited hip flexion (17.4 ± 4.4 in the LBP group, 20.8 ± 2.6 in the healthy group; t = 2.63, p = 0.014). The angle of the lumbar flexion (4.8 ± 2.2 in the LBP group, 2.6 ± 2.0 in the healthy group; t = -2.96, p = 0.006) and posterior pelvic tilting (5.0 ± 2.6 in the LBP group, 2.9 ± 2.0 in the healthy group; t = 2.48 p = 0.019), however, were significantly greater in patients with this condition. The results of this study suggest that limited hip flexion in LBP can contribute to excessive lumbar flexion and posterior pelvic tilting during hip flexion in the sitting position. Further studies are required to confirm whether improving the hip flexion range of motion can reduce excessive lumbar flexion in patients with LBP accompanying limited hip flexion.

  12. Biomechanical consequences of adding plantar fascia release to metatarsal osteotomies: Changes in forefoot plantar pressures.

    PubMed

    Aydogan, Umur; Roush, Evan P; Moore, Blake E; Andrews, Seth H; Lewis, Gregory S

    2017-04-01

    Destruction of the normal metatarsal arch by a long metatarsal is often a cause for metatarsalgia. When surgery is warranted, distal oblique, or proximal dorsiflexion osteotomies of the long metatarsal bones are commonly used. The plantar fascia has anatomical connection to all metatarsal heads. There is controversial scientific evidence on the effect of plantar fascia release on forefoot biomechanics. In this cadaveric biomechanical study, we hypothesized that plantar fascia release would augment the plantar metatarsal pressure decreasing effects of two common second metatarsal osteotomy techniques. Six matched pairs of foot and ankle specimens were mounted on a pressure mat loading platform. Two randomly assigned surgery groups, which had received either distal oblique, or proximal dorsiflexion osteotomy of the second metatarsal, were evaluated before and after plantar fasciectomy. Specimens were loaded up to a ground reaction force of 400 N at varying Achilles tendon forces. Average pressures, peak pressures, and contact areas were analyzed. Supporting our hypothesis, average pressures under the second metatarsal during 600 N Achilles load were decreased by plantar fascia release following proximal osteotomy (p < 0.05). However contrary to our hypothesis, peak pressures under the second metatarsal were significantly increased by plantar fascia release following modified distal osteotomy, under multiple Achilles loading conditions (p < 0.05). Plantar fasciotomy should not be added to distal metatarsal osteotomy in the treatment of metatarsalgia. If proximal dorsiflexion osteotomy would be preferred, plantar fasciotomy should be approached cautiously not to disturb the forefoot biomechanics. © 2016 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 35:800-804, 2017. © 2016 Orthopaedic Research Society. Published by Wiley Periodicals, Inc.

  13. The deep plantar arch in humans: constitution and topography.

    PubMed

    Gabrielli, C; Olave, E; Mandiola, E; Rodrigues, C F; Prates, J C

    2001-01-01

    The integrity of the various structures within the feet depends on their blood supply. Lesions of the feet often require revascularization, which if successful avoids the need for amputation. To provide greater anatomical detail to aid vascular surgery and imaging, the anatomy and constitution of the deep plantar arch was studied in 50 adult cadaveric feet. The arteries of the foot were injected with red neoprene latex and dissected under magnification. The deep plantar arch, present in all feet, was the result of anastomosis between the deep plantar artery and the deep branch of the lateral plantar artery. The deep plantar artery was predominant in 72% of specimens (Type I arches) and the lateral plantar artery in 22% (Type II), with the contribution being equal in 6% (Type III). The medial plantar artery contributed to the medial segment of the deep plantar arch by its deep branch in 12% of specimens. The distance between the deep plantar arch and each interdigital commissure was generally constant, averaging 29% of total foot length. The deep plantar arch was located in the middle third of the foot in all specimens, being in the distal part of this third in 90%. The deep plantar arch is, therefore formed mainly by the deep plantar artery, a branch of the dorsal artery of foot; its location can be estimated if foot length is known.

  14. The bending stiffness of shoes is beneficial to running energetics if it does not disturb the natural MTP joint flexion.

    PubMed

    Oh, Keonyoung; Park, Sukyung

    2017-02-28

    A local minimum for running energetics has been reported for a specific bending stiffness, implying that shoe stiffness assists in running propulsion. However, the determinant of the metabolic optimum remains unknown. Highly stiff shoes significantly increase the moment arm of the ground reaction force (GRF) and reduce the leverage effect of joint torque at ground push-off. Inspired by previous findings, we hypothesized that the restriction of the natural metatarsophalangeal (MTP) flexion caused by stiffened shoes and the corresponding joint torque changes may reduce the benefit of shoe bending stiffness to running energetics. We proposed the critical stiffness, k cr , which is defined as the ratio of the MTP joint (MTPJ) torque to the maximal MTPJ flexion angle, as a possible threshold of the elastic benefit of shoe stiffness. 19 subjects participated in a running test while wearing insoles with five different bending stiffness levels. Joint angles, GRFs, and metabolic costs were measured and analyzed as functions of the shoe stiffness. No significant changes were found in the take-off velocity of the center of mass (CoM), but the horizontal ground push-offs were significantly reduced at different shoe stiffness levels, indicating that complementary changes in the lower-limb joint torques were introduced to maintain steady running. Slight increases in the ankle, knee, and hip joint angular impulses were observed at stiffness levels exceeding the critical stiffness, whereas the angular impulse at the MTPJ was significantly reduced. These results indicate that the shoe bending stiffness is beneficial to running energetics if it does not disturb the natural MTPJ flexion. Copyright © 2017 Elsevier Ltd. All rights reserved.

  15. Effect of immobilization and retraining on torque-velocity relationship of human knee flexor and extensor muscles.

    PubMed

    Labarque, V L; Eijnde, B Op 't; Van Leemputte, M

    2002-01-01

    The effect of 2 weeks immobilization of the uninjured right knee and 10 weeks of retraining on muscle torque-velocity characteristics was investigated in nine young subjects. Left and right knee extension and flexion maximal voluntary isometric torque (Tmax) and dynamic torque at 60 degrees s(-1) (T60) and 180 degrees x s(-1) (T180) were measured before (PRE) and after immobilization (POST) and after 3 (R3) and 10 (R10) weeks of dynamic retraining. The torque-velocity relationship was quantified by expressing T60 and T180 relative to Tmax (NT60 and NT180, respectively). For the right extensor muscles, percutaneous biopsy samples were obtained from the vastus lateralis muscle and fibre type distribution was measured. POST extension and flexion torque (mean of Tmax, T60 and T180) decreased by 27% and 11%, respectively. During the course of the experiment, the changes in NT60 and NT180 were similar. POST extensor muscle NTV (mean of NT60 and NT180) was decreased significantly (12%, P<0.05), but no significant change was found for flexor muscle NTV (+ 3%). At R3 Tmax, dynamic torque and NTV were restored to normal. Unlike isometric torque, NTV did not change from R3 to R10. No changes in fibre type distribution were found. The adaptation of muscle length is suggested as the mechanism to explain the change in NTV.

  16. The effects of joint aspiration and intra-articular corticosteroid injection on flexion reflex excitability, quadriceps strength and pain in individuals with knee synovitis: a prospective observational study.

    PubMed

    Rice, David Andrew; McNair, Peter John; Lewis, Gwyn Nancy; Dalbeth, Nicola

    2015-07-28

    Substantial weakness of the quadriceps muscles is typically observed in patients with arthritis. This is partly due to ongoing neural inhibition that prevents the quadriceps from being fully activated. Evidence from animal studies suggests enhanced flexion reflex excitability may contribute to this weakness. This prospective observational study examined the effects of joint aspiration and intra-articular corticosteroid injection on flexion reflex excitability, quadriceps muscle strength and knee pain in individuals with knee synovitis. Sixteen patients with chronic arthritis and clinically active synovitis of the knee participated in this study. Knee pain flexion reflex threshold, and quadriceps peak torque were measured at baseline, immediately after knee joint aspiration alone and 5 ± 2 and 15 ± 2 days after knee joint aspiration and the injection of 40 mg of methylprednisolone acetate. Compared to baseline, knee pain was significantly reduced 5 (p = 0.001) and 15 days (p = 0.009) post intervention. Flexion reflex threshold increased immediately after joint aspiration (p = 0.009) and 5 (p = 0.01) and 15 days (p = 0.002) post intervention. Quadriceps peak torque increased immediately after joint aspiration (p = 0.004) and 5 (p = 0.001) and 15 days (p <0.001) post intervention. The findings from this study suggest that altered sensory output from an inflamed joint may increase flexion reflex excitability in humans, as has previously been shown in animals. Joint aspiration and corticosteroid injection may be a clinically useful intervention to reverse quadriceps muscle weakness in individuals with knee synovitis.

  17. Plantar hyperhidrosis: A review of current management.

    PubMed

    Singh, Sanjay; Kaur, Simranjit; Wilson, Paul

    2016-11-01

    To critically appraise current literature regarding the management of plantar hyperhidrosis in the form of a structured review. A literature search was conducted using various databases and search criteria. The literature reports the use of conservative, medical and surgical treatment modalities for the management of plantar hyperhidrosis. However, long-term follow-up data are rare and some treatment modalities currently available are not fully understood. There is a considerable dearth in the literature on the management of plantar hyperhidrosis. Further study in larger populations with longer follow-up times is critical to access the long-term effects of treatment. Nonetheless, iontophoresis, botulinum toxin injection and lumbar sympathectomy are promising treatment modalities for this disorder.

  18. Plantar flexor muscle weakness and fatigue in spastic cerebral palsy patients.

    PubMed

    Neyroud, Daria; Armand, Stéphane; De Coulon, Geraldo; Sarah R Dias Da Silva; Maffiuletti, Nicola A; Kayser, Bengt; Place, Nicolas

    2017-02-01

    Patients with cerebral palsy develop an important muscle weakness which might affect the aetiology and extent of exercise-induced neuromuscular fatigue. This study evaluated the aetiology and extent of plantar flexor neuromuscular fatigue in patients with cerebral palsy. Ten patients with cerebral palsy and 10 age- and sex-matched healthy individuals (∼20 years old, 6 females) performed four 30-s maximal isometric plantar flexions interspaced by a resting period of 2-3s to elicit a resting twitch. Maximal voluntary contraction force, voluntary activation level and peak twitch were quantified before and immediately after the fatiguing task. Before fatigue, patients with cerebral palsy were weaker than healthy individuals (341±134N vs. 858±151N, p<0.05) and presented lower voluntary activation (73±19% vs. 90±9%, p<0.05) and peak twitch (100±28N vs. 199±33N, p<0.05). Maximal voluntary contraction force was not significantly reduced in patients with cerebral palsy following the fatiguing task (-10±23%, p>0.05), whereas it decreased by 30±12% (p<0.05) in healthy individuals. Plantar flexor muscles of patients with cerebral palsy were weaker than their healthy peers but showed greater fatigue resistance. Cerebral palsy is a widely defined pathology that is known to result in muscle weakness. The extent and origin of muscle weakness were the topic of several previous investigations; however some discrepant results were reported in the literature regarding how it might affect the development of exercise-induced neuromuscular fatigue. Importantly, most of the studies interested in the assessment of fatigue in patients with cerebral palsy did so with general questionnaires and reported increased levels of fatigue. Yet, exercise-induced neuromuscular fatigue was quantified in just a few studies and it was found that young patients with cerebral palsy might be more fatigue resistant that their peers. Thus, it appears that (i) conflicting results exist regarding

  19. [The use of papain in plantar ulcers].

    PubMed

    Otuka, E S; Pedrazzani, E S; Pioto, M P

    1996-01-01

    This work has as a goal to contribute to decrease the inability in leprosy and continuous recurrence of plantar ulcers, through the use of a treatment method using papaine and actions of health education. This work has been done in a health centre with patients that presented plantar ulcers and agreed to participate in the proposed treatment. Analysing and comparing the obtained data before and after treatment, a greater adhesion of patients to this treatment, a quicker healing in relation to other methods used before and a greater interaction with the patient has been observed.

  20. Interdependence of torque, joint angle, angular velocity and muscle action during human multi-joint leg extension.

    PubMed

    Hahn, Daniel; Herzog, Walter; Schwirtz, Ansgar

    2014-08-01

    Force and torque production of human muscles depends upon their lengths and contraction velocity. However, these factors are widely assumed to be independent of each other and the few studies that dealt with interactions of torque, angle and angular velocity are based on isolated single-joint movements. Thus, the purpose of this study was to determine force/torque-angle and force/torque-angular velocity properties for multi-joint leg extensions. Human leg extension was investigated (n = 18) on a motor-driven leg press dynamometer while measuring external reaction forces at the feet. Extensor torque in the knee joint was calculated using inverse dynamics. Isometric contractions were performed at eight joint angle configurations of the lower limb corresponding to increments of 10° at the knee from 30 to 100° of knee flexion. Concentric and eccentric contractions were performed over the same range of motion at mean angular velocities of the knee from 30 to 240° s(-1). For contractions of increasing velocity, optimum knee angle shifted from 52 ± 7 to 64 ± 4° knee flexion. Furthermore, the curvature of the concentric force/torque-angular velocity relations varied with joint angles and maximum angular velocities increased from 866 ± 79 to 1,238 ± 132° s(-1) for 90-50° knee flexion. Normalised eccentric forces/torques ranged from 0.85 ± 0.12 to 1.32 ± 0.16 of their isometric reference, only showing significant increases above isometric and an effect of angular velocity for joint angles greater than optimum knee angle. The findings reveal that force/torque production during multi-joint leg extension depends on the combined effects of angle and angular velocity. This finding should be accounted for in modelling and optimisation of human movement.

  1. Percutaneous release of the plantar fascia. New surgical procedure.

    PubMed

    Oliva, Francesco; Piccirilli, Eleonora; Tarantino, Umberto; Maffulli, Nicola

    2017-01-01

    Plantar fasciopathy presents with pain at the plantar and medial aspect of the heel. If chronic, it can negatively impact on quality of life. Plantar fasciopathy is not always self-limiting, and can be debilitating. Surgical management involves different procedures. We describe a percutaneous plantar fascia release. A minimally invasive access to the plantar tuberosity of the calcaneus is performed, and a small scalpel blade is used to release the fascia. With this procedure, skin healing problems, nerve injuries, infection and prolonged recovery time are minimised, allowing early return to normal activities. V.

  2. Percutaneous release of the plantar fascia. New surgical procedure

    PubMed Central

    Oliva, Francesco; Piccirilli, Eleonora; Tarantino, Umberto; Maffulli, Nicola

    2017-01-01

    Summary Background Plantar fasciopathy presents with pain at the plantar and medial aspect of the heel. If chronic, it can negatively impact on quality of life. Plantar fasciopathy is not always self-limiting, and can be debilitating. Methods Surgical management involves different procedures. We describe a percutaneous plantar fascia release. A minimally invasive access to the plantar tuberosity of the calcaneus is performed, and a small scalpel blade is used to release the fascia. Conclusion With this procedure, skin healing problems, nerve injuries, infection and prolonged recovery time are minimised, allowing early return to normal activities. Level of Evidence V. PMID:29264346

  3. Child–adult differences in the kinetics of torque development

    PubMed Central

    DOTAN, RAFFY; MITCHELL, CAMERON; COHEN, ROTEM; GABRIEL, DAVID; KLENTROU, PANAGIOTA; FALK, BAREKET

    2013-01-01

    Children have lower size-normalised maximal voluntary force, speed, and power than adults. It has been hypothesised that these and other age-related performance differences are due to lesser type-II motor-unit utilisation in children. This should be manifested as slower force kinetics in explosive muscle contractions. The purpose of this study was to investigate the nature of child–adult force-kinetics differences and whether the latter could support that hypothesis. Untrained boys (n = 20) and men (n = 20) (10.1 ± 1.3 and 22.9 ± 4.4 years, respectively), performed maximal, explosive, isometric elbow flexions and knee extensions on a Biodex dynamometer. Peak torque (MVC), times to 10–100% MVC, and other kinetics parameters were determined. The boys’ body-mass-normalised knee extension MVC, peak rate of torque development, and %MVC at 100 ms were 26, 17 and 23% lower compared with the men and their times to 30% and 80% MVC were 24 and 48% longer, respectively. Elbow flexion kinetics showed similar or greater differences. The findings illuminate boys’ inherent disadvantage in tasks requiring speed or explosive force. It is demonstrated that the extent of the boys–men kinetics disparity cannot be explained by muscle-composition and/or musculo-tendinous-stiffness differences. We suggest therefore that the findings indirectly support children’s lower utilisation of type-II motor units. PMID:23320937

  4. Twin-enhanced magnetic torque

    NASA Astrophysics Data System (ADS)

    Hobza, Anthony; García-Cervera, Carlos J.; Müllner, Peter

    2018-07-01

    Magnetic shape memory alloys experience magnetic-field-induced torque due to magnetocrystalline anisotropy and shape anisotropy. In a homogeneous magnetic field, torque results in bending of long samples. This study investigates the torque on a single crystal of Ni-Mn-Ga magnetic shape memory alloy constrained with respect to bending in an external magnetic field. The dependence of the torque on external magnetic field magnitude, strain, and twin boundary structure was studied experimentally and with computer simulations. With increasing magnetic field, the torque increased until it reached a maximum near 700 mT. Above 200 mT, the torque was not symmetric about the equilibrium orientation for a sample with one twin boundary. The torque on two specimen with equal strain but different twin boundary structures varied systematically with the spatial arrangement of crystallographic twins. Numerical simulations show that twin boundaries suppress the formation of 180° domains if the direction of easy magnetization between two twin boundaries is parallel to a free surface and the magnetic field is perpendicular to that surface. For a particular twin microstructure, the torque decreases with increasing strain by a factor of six due to the mutual compensation of magnetocrystalline and shape anisotropy. When free rotation is suppressed such as in transducers of magneto-mechanical actuators, magnetic-field-induced torque creates strong bending forces, which may cause friction and failure under cyclic loading.

  5. Risk factors affecting chronic rupture of the plantar fascia.

    PubMed

    Lee, Ho Seong; Choi, Young Rak; Kim, Sang Woo; Lee, Jin Yong; Seo, Jeong Ho; Jeong, Jae Jung

    2014-03-01

    Prior to 1994, plantar fascia ruptures were considered as an acute injury that occurred primarily in athletes. However, plantar fascia ruptures have recently been reported in the setting of preexisting plantar fasciitis. We analyzed risk factors causing plantar fascia rupture in the presence of preexisting plantar fasciitis. We retrospectively reviewed 286 patients with plantar fasciitis who were referred from private clinics between March 2004 and February 2008. Patients were divided into those with or without a plantar fascia rupture. There were 35 patients in the rupture group and 251 in the nonrupture group. The clinical characteristics and risk factors for plantar fascia rupture were compared between the 2 groups. We compared age, gender, the affected site, visual analog scale pain score, previous treatment regimen, body mass index, degree of ankle dorsiflexion, the use of steroid injections, the extent of activity, calcaneal pitch angle, the presence of a calcaneal spur, and heel alignment between the 2 groups. Of the assessed risk factors, only steroid injection was associated with the occurrence of a plantar fascia rupture. Among the 35 patients with a rupture, 33 had received steroid injections. The odds ratio of steroid injection was 33. Steroid injections for plantar fasciitis should be cautiously administered because of the higher risk for plantar fascia rupture. Level III, retrospective comparative study.

  6. Plantar fasciitis: what is the diagnosis and treatment?

    PubMed

    Johnson, Rachel E; Haas, Kim; Lindow, Kyle; Shields, Robert

    2014-01-01

    Foot pain, specifically plantar heel pain, is a common complaint among patients in a podiatric or orthopaedic office setting but may be seen in primary care offices, urgent care centers, or emergency departments as well. There are numerous causes for heel pain, but plantar fasciitis is the most frequent cause. The diagnosis of plantar fasciitis is generally made clinically, but there are many diagnostic modalities that may be used to confirm the diagnosis. Treatment of plantar fasciitis ranges from conservative measures to surgical interventions, but most cases of plantar fasciitis can be managed conservatively. There is no definitive treatment proven to be the best option for plantar fasciitis. Treatment is patient dependent and commonly requires a combination of different modalities to successfully alleviate the symptoms. In this article, plantar fasciitis from defining the disorder, diagnosis, and treatment are discussed.

  7. Incidence of plantar fascia ruptures following corticosteroid injection.

    PubMed

    Kim, Chul; Cashdollar, Michael R; Mendicino, Robert W; Catanzariti, Alan R; Fuge, LaDonna

    2010-12-01

    Plantar fasciitis is commonly treated with corticosteroid injections to decrease pain and inflammation. Therapeutic benefits often vary in terms of efficacy and duration. Rupture of the plantar fascia has been reported as a possible complication following corticosteroid injection. A retrospective chart review of 120 patients who received corticosteroid injection for plantar fasciitis was performed at the authors' institution to determine the incidence of plantar fascia rupture. The plantar fascia rupture was diagnosed clinically and confirmed with magnetic resonance imaging. Various factors were analyzed, including the number of injections, interval between injections, body mass index (BMI), and activity level. Four patients (2.4%) consequently experienced plantar fascia rupture following an average of 2.67 injections. The average BMI of these patients was 38.6 kg/m². The authors conclude that corticosteroid injection therapy appears to be a safe and effective form of nonoperative treatment with minimal complications and a relatively low incident of plantar fascia rupture.

  8. Optimal sagittal motion axis for trunk extension and flexion tests in chronic low back trouble.

    PubMed

    Rantanen, P; Nykvist, F

    2000-11-01

    To find the optimal height for sagittal motion axis for trunk strength test in chronic low back trouble. Cross-sectional study. The strength of trunk muscles of low back pain patients is decreased. The measured strength depends on the height of the sagittal motion axis but the differences between patients and controls are not known. 114 (67 female) patients with chronic low back trouble are classified according to Quebec Task Force, 50 (31 female) patients with rheumatic disorder, but without low back trouble, and 33 (22 female) healthy controls, no appreciable physical differences but clear differences in Oswestry score. Isometric trunk extension-flexion test with different heights for the pelvic fulcrum. Force decreased in extension, increased in flexion, and torque increased both in flexion and extension in every group (P<0.001) as the fulcrum was moved caudally. The male controls were stronger than patients with low back trouble (P<0.01). The female controls were stronger only if the fulcrum was set at the hip joint level (P<0.05). There were no differences between patients with rheumatic disorder and low back trouble, except in extension if the fulcrum was at the hip joint level (P<0.02). The rotation axis in trunk extension-flexion strength test should be set at the level of the hip joint. Trunk muscle weakness is a common sign of different rheumatic disorders. Proper setting of sagittal motion axis and concomitant measurement of trunk and hip extensor or flexor muscles increases the specificity of the strength test for low back trouble.

  9. Plantar fascia coronal length: a new parameter for plantar fascia assessment.

    PubMed

    Sari, Ahmet Sinan; Demircay, Emre; Cakmak, Gokhan; Sahin, M Sukru; Tuncay, I Cengiz; Altun, Suleyman

    2015-01-01

    The effects of gender and various anthropometric variables were previously reported as significant predictors of plantar fascia thickness. Although a strong correlation between either the body weight or body mass index (BMI) and plantar fascia thickness were not demonstrated, a moderate relation was stated. We retrospectively investigated the role of gender, height, weight, and body mass index on plantar fascia thickness at the calcaneal origin (PFCO) and 1 cm distal from the calcaneal origin (PF1cm) and the coronal length of the plantar fascia at the calcaneal origin (CLPF) in healthy subjects. The PFCO, PF1cm, and CLPF were retrospectively measured from magnetic resonance images of 100 healthy subjects. The gender, height, weight, and body mass index of the participants were also noted. Gender was a predictive factor for the length of the CLPF. The subjects with a BMI >25 kg/m(2) had a significantly greater PFCO, PF1cm, and CLPF. Height was mildly and BMI and weight were moderately related to the PFCO. However the CLPF showed a better correlation with height, BMI, and weight than that of plantar fascia thickness. CLPF better reflected the role of weight, BMI, and height than its thickness. It is a new parameter that could be valuable in the evaluation of plantar fascia disorders. Copyright © 2015 American College of Foot and Ankle Surgeons. Published by Elsevier Inc. All rights reserved.

  10. Manual Torque Data Study

    SciTech Connect

    Mundt, Mark Osroe; Martinez, Matthew Ronald; Varela, Jeanette Judith

    At the Pantex Plant in Amarillo, TX, Production Technicians (PTs) build and disassemble nuclear weapon systems. The weapons are held in an integrated work stand for stability and to increase the safety environment for the workers and for the materials being processed. There are many occasions in which a knob must be turned to tighten an assembly part. This can help to secure or manipulate pieces of the system. As there are so many knobs to turn, the instructions given to the PTs are to twist the knob to a hand-tight setting, without the aid of a torque wrench. Theremore » are inherent risks in this procedure as the knobs can be tightened too loosely such that the apparatus falls apart or too tightly such that the force can crush or pinch components in the system that contain energetic materials. We want to study these operations at Pantex. Our goal is to collect torque data to assess the safety and reliability of humantooling interfaces.« less

  11. Treatment of Plantar Fasciitis With Botulinum Toxin.

    PubMed

    Ahmad, Jamal; Ahmad, Stacy H; Jones, Kennis

    2017-01-01

    This study examined the effect of botulinum toxin upon plantar fasciitis through a randomized, controlled, and blinded trial. Between 2012 and 2015, 50 patients presented with plantar fasciitis. Twenty-five patients each randomly received an IncobotulinumtoxinA (IBTA) or saline injection of their affected foot. Pre- and postinjection function and pain were graded with the Foot and Ankle Ability Measures (FAAM) and visual analog scale (VAS), respectively. All 50 study patients who randomly received either placebo or IBTA presented at 6 and 12 months after injection. At 6 months, the mean FAAM increased from 35.9 to 40.9 of 100, and the mean pain score decreased from 8.4 to 7.9 of 10 within the placebo group. At 6 months, the mean FAAM increased from 36.3 to 73.8 of 100, and mean pain score decreased from 7.2 to 3.6 of 10 within the IBTA group. These postinjection scores were significantly better than the placebo group ( P = .01). At 12 months after injection, the IBTA group maintained significantly better function and pain than the placebo group ( P < .05). By that time, 0 (0%) and 3 (12%) patients who received IBTA and saline, respectively, underwent surgery for recalcitrant plantar fasciitis ( P < .005). Compared with placebo saline injection, using IBTA to treat plantar fasciitis resulted in significantly better improvement in foot function and pain. IBTA also lessened the need for operative treatment of plantar fasciitis. I, Randomized, double-blinded, placebo-controlled study.

  12. Joint torques and joint reaction forces during squatting with a forward or backward inclined Smith machine.

    PubMed

    Biscarini, Andrea; Botti, Fabio M; Pettorossi, Vito E

    2013-02-01

    We developed a biomechanical model to determine the joint torques and loadings during squatting with a backward/forward-inclined Smith machine. The Smith squat allows a large variety of body positioning (trunk tilt, foot placement, combinations of joint angles) and easy control of weight distribution between forefoot and heel. These distinctive aspects of the exercise can be managed concurrently with the equipment inclination selected to unload specific joint structures while activating specific muscle groups. A backward (forward) equipment inclination decreases (increases) knee torque, and compressive tibiofemoral and patellofemoral forces, while enhances (depresses) hip and lumbosacral torques. For small knee flexion angles, the strain-force on the posterior cruciate ligament increases (decreases) with a backward (forward) equipment inclination, whereas for large knee flexion angles, this behavior is reversed. In the 0 to 60 degree range of knee flexion angles, loads on both cruciate ligaments may be simultaneously suppressed by a 30 degree backward equipment inclination and selecting, for each value of the knee angle, specific pairs of ankle and hip angles. The anterior cruciate ligament is safely maintained unloaded by squatting with backward equipment inclination and uniform/forward foot weight distribution. The conditions for the development of anterior cruciate ligament strain forces are clearly explained.

  13. Comparison of knee flexion isokinetic deficits between seated and prone positions after ACL reconstruction with hamstrings graft: Implications for rehabilitation and return to sports decisions.

    PubMed

    Koutras, Georgios; Bernard, Manfred; Terzidis, Ioannis P; Papadopoulos, Pericles; Georgoulis, Anastasios; Pappas, Evangelos

    2016-07-01

    Hamstrings grafts are commonly used in ACL reconstruction, however, the effect of graft harvesting on knee flexion strength has not been longitudinally evaluated in functional positions. We hypothesized that greater deficits in knee flexion strength exist in the prone compared to the seated position and these deficits remain as rehabilitation progresses. Case series. Forty-two consecutive patients who underwent ACL reconstruction with a hamstrings graft were followed prospectively for 9 months. Isokinetic knee flexion strength at a slow and a fast speed were collected at 3, 4, 6, and 9 months in two different positions: conventional (seated) and functional (0° of hip flexion). Peak torque knee flexion deficits were higher in the prone position compared to the seated position by an average of 6.5% at 60°/s and 9.1% at 180°/s (p<0.001). Measuring knee flexion strength in prone demonstrates higher deficits than in the conventional seated position. Most athletes would not be cleared to return to sports even at 9 months after surgery with this method. Copyright © 2015 Sports Medicine Australia. Published by Elsevier Ltd. All rights reserved.

  14. Torque control for electric motors

    NASA Technical Reports Server (NTRS)

    Bernard, C. A.

    1980-01-01

    Method for adjusting electric-motor torque output to accomodate various loads utilizes phase-lock loop to control relay connected to starting circuit. As load is imposed, motor slows down, and phase lock is lost. Phase-lock signal triggers relay to power starting coil and generate additional torque. Once phase lock is recoverd, relay restores starting circuit to its normal operating mode.

  15. Do peak torque angles of muscles change following anterior cruciate ligament reconstruction using hamstring or patellar tendon graft?

    PubMed

    Yosmaoğlu, Hayri Baran; Baltacı, Gül; Sönmezer, Emel; Özer, Hamza; Doğan, Deha

    2017-12-01

    This study aims to compare the effects of anterior cruciate ligament (ACL) reconstruction using autogenous hamstring or patellar tendon graft on the peak torque angle. The study included 132 patients (103 males, 29 females; mean age 29±9 year) who were performed ACL reconstruction with autogenous hamstring or patellar tendon graft. The peak torque angles in the quadriceps and hamstring muscles were recorded using an isokinetic dynamometer. Angle of peak knee flexion torque occurred significantly earlier within the range of motion on the operated side than nonoperated side at 180°/second in the hamstring tendon group. Angle of peak knee extension torque occurred significantly earlier within the range of motion on the operated side than nonoperated side at 180°/second in the patellar tendon group. There were no statistically significant differences in the flexion and extension peak torque angles between the operated and nonoperated knees at 60°/second in both groups. The angle of peak torque at relatively high angular velocities is affected after ACL reconstruction in patients with hamstring or patellar tendon grafts. The graft donor site directly influences this parameter. This finding may be important for clinicians in terms of preventing re-injury.

  16. Provocative mechanical tests of the peripheral nervous system affect the joint torque-angle during passive knee motion.

    PubMed

    Andrade, R J; Freitas, S R; Vaz, J R; Bruno, P M; Pezarat-Correia, P

    2015-06-01

    This study aimed to determine the influence of the head, upper trunk, and foot position on the passive knee extension (PKE) torque-angle response. PKE tests were performed in 10 healthy subjects using an isokinetic dynamometer at 2°/s. Subjects lay in the supine position with their hips flexed to 90°. The knee angle, passive torque, surface electromyography (EMG) of the semitendinosus and quadriceps vastus medialis, and stretch discomfort were recorded in six body positions during PKE. The different maximal active positions of the cervical spine (neutral; flexion; extension), thoracic spine (neutral; flexion), and ankle (neutral; dorsiflexion) were passively combined for the tests. Visual analog scale scores and EMG were unaffected by body segment positioning. An effect of the ankle joint was verified on the peak torque and knee maximum angle when the ankle was in the dorsiflexion position (P < 0.05). Upper trunk positioning had an effect on the knee submaximal torque (P < 0.05), observed as an increase in the knee passive submaximal torque when the cervical and thoracic spines were flexed (P < 0.05). In conclusion, other apparently mechanical unrelated body segments influence torque-angle response since different positions of head, upper trunk, and foot induce dissimilar knee mechanical responses during passive extension. © 2014 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

  17. Influence of different safety shoes on gait and plantar pressure: a standardized examination of workers in the automotive industry.

    PubMed

    Ochsmann, Elke; Noll, Ulrike; Ellegast, Rolf; Hermanns, Ingo; Kraus, Thomas

    2016-09-30

    Working conditions, such as walking and standing on hard surfaces, can increase the development of musculoskeletal complaints. At the interface between flooring and musculoskeletal system, safety shoes may play an important role in the well-being of employees. The aim of this study was to evaluate the effects of different safety shoes on gait and plantar pressure distributions on industrial flooring. Twenty automotive workers were individually fitted out with three different pairs of safety shoes ( "normal" shoes, cushioned shoes, and midfoot bearing shoes). They walked at a given speed of 1.5 m/s. The CUELA measuring system and shoe insoles were used for gait analysis and plantar pressure measurements, respectively. Statistical analysis was conducted by ANOVA analysis for repeated measures. Walking with cushioned safety shoes or a midfoot bearing safety shoe led to a significant decrease of the average trunk inclination (p<0.005). Furthermore, the average hip flexion angle decreased for cushioned shoes as well as midfoot bearing shoes (p<0.002). The range of motion of the knee joint increased for cushioned shoes. As expected, plantar pressure distributions varied significantly between cushioned or midfoot bearing shoes and shoes without ergonomic components. The overall function of safety shoes is the avoidance of injury in case of an industrial accident, but in addition, safety shoes could be a long-term preventive instrument for maintaining health of the employees' musculoskeletal system, as they are able to affect gait parameters. Further research needs to focus on safety shoes in working situations.

  18. Isokinetic Identification of Knee Joint Torques before and after Anterior Cruciate Ligament Reconstruction

    PubMed Central

    Czaplicki, Adam; Jarocka, Marta; Walawski, Jacek

    2015-01-01

    The aim of this study was to evaluate the serial change of isokinetic muscle strength of the knees before and after anterior cruciate ligament reconstruction (ACLR) in physically active males and to estimate the time of return to full physical fitness. Extension and flexion torques were measured for the injured and healthy limbs at two angular velocities approximately 1.5 months before the surgery and 3, 6, and 12 months after ACLR. Significant differences (p ≤ 0.05) in peak knee extension and flexion torques, hamstring/quadriceps (H/Q) strength ratios, uninvolved/involved limb peak torque ratios, and the normalized work of these muscles between the four stages of rehabilitation were identified. Significant differences between extension peak torques for the injured and healthy limbs were also detected at all stages. The obtained results showed that 12 months of rehabilitation were insufficient for the involved knee joint to recover its strength to the level of strength of the uninvolved knee joint. The results helped to evaluate the progress of the rehabilitation and to implement necessary modifications optimizing the rehabilitation training program. The results of the study may also be used as referential data for physically active males of similar age. PMID:26646385

  19. Management of plantar fasciitis in the outpatient setting

    PubMed Central

    Lim, Ang Tee; How, Choon How; Tan, Benedict

    2016-01-01

    Plantar fasciitis is a very common cause of inferior heel pain that can be triggered and aggravated by prolonged standing, walking, running and obesity, among other factors. Treatments are largely noninvasive and efficacious. Supportive treatments, including the plantar fascia-specific stretch, calf stretching, appropriate orthotics and night dorsiflexion splinting, can alleviate plantar fascia pain. While local injections of corticosteroids can help with pain relief, the effects are short-lived and must be weighed against the risk of fat pad atrophy and plantar fascia rupture. Ultrasonography-guided focal extracorporeal shock wave therapy is useful for patients with chronic plantar fasciitis and referrals for this treatment can be made in recalcitrant cases. Activity modification to decrease cyclical repetitive loading of the plantar fascia should be advised during the treatment phase regardless of the chosen treatment modality. PMID:27075037

  20. Management of plantar fasciitis in the outpatient setting.

    PubMed

    Lim, Ang Tee; How, Choon How; Tan, Benedict

    2016-04-01

    Plantar fasciitis is a very common cause of inferior heel pain that can be triggered and aggravated by prolonged standing, walking, running and obesity, among other factors. Treatments are largely noninvasive and efficacious. Supportive treatments, including the plantar fascia-specific stretch, calf stretching, appropriate orthotics and night dorsiflexion splinting, can alleviate plantar fascia pain. While local injections of corticosteroids can help with pain relief, the effects are short-lived and must be weighed against the risk of fat pad atrophy and plantar fascia rupture. Ultrasonography-guided focal extracorporeal shock wave therapy is useful for patients with chronic plantar fasciitis and referrals for this treatment can be made in recalcitrant cases. Activity modification to decrease cyclical repetitive loading of the plantar fascia should be advised during the treatment phase regardless of the chosen treatment modality. Copyright: © Singapore Medical Association.

  1. Mechanical Information of Plantar Fascia during Normal Gait

    NASA Astrophysics Data System (ADS)

    Gu, Yaodong; Li, Zhiyong

    The plantar fascia is an important foot tissue in stabilizing the longitudinal arch of human foot. Direct measurement to monitor the mechanical situation of plantar fascia at human locomotion is difficult. The purpose of this study was to construct a three-dimensional finite element model of the foot to calculate the internal stress/strain value of plantar fascia during different stage of gait. The simulated stress distribution of plantar fascia was the lowest at heel-strike, which concentrated on the medial side of calcaneal tubercle. The peak stress of plantar fascia was appeared at push-off, and the value is more than 5 times of the heel-strike position. Current FE model was able to explore the plantar fascia tension trend at the main sub-phases of foot. More detailed fascia model and intrinsic muscle forces could be developed in the further study.

  2. Screening Method Based on Walking Plantar Impulse for Detecting Musculoskeletal Senescence and Injury

    PubMed Central

    Fan, Yifang; Fan, Yubo; Li, Zhiyu; Newman, Tony; Lv, Changsheng; Zhou, Yi

    2013-01-01

    No consensus has been reached on how musculoskeletal system injuries or aging can be explained by a walking plantar impulse. We standardize the plantar impulse by defining a principal axis of plantar impulse. Based upon this standardized plantar impulse, two indexes are presented: plantar pressure record time series and plantar-impulse distribution along the principal axis of plantar impulse. These indexes are applied to analyze the plantar impulse collected by plantar pressure plates from three sources: Achilles tendon ruptures; elderly people (ages 62–71); and young people (ages 19–23). Our findings reveal that plantar impulse distribution curves for Achilles tendon ruptures change irregularly with subjects’ walking speed changes. When comparing distribution curves of the young, we see a significant difference in the elderly subjects’ phalanges plantar pressure record time series. This verifies our hypothesis that a plantar impulse can function as a means to assess and evaluate musculoskeletal system injuries and aging. PMID:24386288

  3. Screening method based on walking plantar impulse for detecting musculoskeletal senescence and injury.

    PubMed

    Fan, Yifang; Fan, Yubo; Li, Zhiyu; Newman, Tony; Lv, Changsheng; Zhou, Yi

    2013-01-01

    No consensus has been reached on how musculoskeletal system injuries or aging can be explained by a walking plantar impulse. We standardize the plantar impulse by defining a principal axis of plantar impulse. Based upon this standardized plantar impulse, two indexes are presented: plantar pressure record time series and plantar-impulse distribution along the principal axis of plantar impulse. These indexes are applied to analyze the plantar impulse collected by plantar pressure plates from three sources: Achilles tendon ruptures; elderly people (ages 62-71); and young people (ages 19-23). Our findings reveal that plantar impulse distribution curves for Achilles tendon ruptures change irregularly with subjects' walking speed changes. When comparing distribution curves of the young, we see a significant difference in the elderly subjects' phalanges plantar pressure record time series. This verifies our hypothesis that a plantar impulse can function as a means to assess and evaluate musculoskeletal system injuries and aging.

  4. The epidemiology and clinical manifestations of hamstring muscle and plantar foot flexor shortening.

    PubMed

    Joźwiak, M; Pietrzak, S; Tobjasz, F

    1997-07-01

    A population of 920 healthy children was studied with the aim of assessing the incidence of hamstring muscle and plantar foot flexor tightness, and to correlate such symptoms with gait, posture, and low back discomfort or pain. Special attention was paid to the popliteal angle and dorsal foot flexion. The borderline values for the popliteal angle in the following age groups were, boys: 3 to 5 years, 40 degrees; 6 to 15 years, 50 degrees; and 16 to 19 years, 40 degrees; girls: 3 to 5 years, 30 degrees; 6 to 14 years, 45 degrees; 15 to 19 years, 30 degrees. The borderline values for dorsal foot flexion in the following age groups were 3 to 4 years, 7 degrees; 5 to 13 years, 10 degrees; and 14 to 19 years, 5 degrees. The results obtained indicate a natural increase in hamstring tightness, particularly shortly before the pubertal growth spurt. This seems to be linked with the natural evolution of lumbar lordosis and pelvic tilt. When hamstring tightness surpassed borderline values, dorsiflexion and lumbar lordosis decreased leading to postural deformities, bending-forward deficit, discomfort when sitting, and a shambling gait.

  5. Effect of Transcutaneous Electrical Nerve Stimulation on Plantar Flexor Muscle Spasticity and Walking Speed in Stroke Patients.

    PubMed

    Laddha, Darshan; Ganesh, G Shankar; Pattnaik, Monalisa; Mohanty, Patitapaban; Mishra, Chittaranjan

    2016-12-01

    Spasticity is a major disabling symptom in patients post stroke. Although studies have demonstrated that transcutaneous electrical nerve stimulation (TENS) can reduce spasticity, the duration of single session TENS is a subject of debate. The purpose of this study was to determine the sustainability of the effects of TENS applied over common peroneal nerve in the reduction of ankle plantar-flexor spasticity and improving gait speed in patients post stroke. Thirty patients (11 women and 19 men) (mean age of 46.46 years) were randomly assigned to group 1 (task oriented exercises), group 2 (TENS for 30 min and task oriented exercises) and group 3 (TENS for 60 min and task oriented exercises) for a period of five sessions per week for 6 weeks. All patients were assessed for ankle plantar-flexor spasticity, passive ankle dorsi-flexion range of motion, clonus and timed up and go test at the time of recruitment to study, at 3 and 6 weeks of therapeutic intervention. The overall results of the study suggest that there was a decrease in ankle plantar flexor spasticity, ankle clonus and timed up and go score in all the groups. A greater reduction of spasticity was seen in TENS groups (groups 2 and 3) when compared to control. No significant improvement was found in timed up and go test (TUG) scores between groups. Both 30 min and 60 min of application of TENS are effective in reducing spasticity of ankle plantar flexors, improving walking ability and increase the effectiveness of task related training. Based on the effect size, we would recommend a longer duration application for the reduction of spasticity. Copyright © 2015 John Wiley & Sons, Ltd. Copyright © 2015 John Wiley & Sons, Ltd.

  6. Histologic anatomy of the lesser metatarsophalangeal joint plantar plate.

    PubMed

    Gregg, J; Marks, P; Silberstein, M; Schneider, T; Kerr, J

    2007-03-01

    The plantar plate is the fibrocartilaginous structure that supports the ball of the foot, withstanding considerable compressive and tensile forces. This study describes the morphology of the plantar plate in order to understand its function and the pathologic disorders associated with it. Eight lesser metatarsophalangeal joint plantar plates from three soft-embalmed cadavers (74-92 years, two males, one female), and eight lesser metatarsophalangeal joint plantar plates from a fresh cadaver (19-year-old male) were obtained for histology assessment. Paraffin sections (10 microm) in the longitudinal and transverse planes were analyzed with bright-field and polarized light microscopy. The central plantar plate collagen bundles run in the longitudinal plane with varying degrees of undulation. The plantar plate borders run transversely and merge with collateral ligaments and the deep transverse intermetatarsal ligament. Bright-field microscopic evaluation shows the plantar aspect of the plantar plate becomes ligament-like the further distally it tapers, containing fewer chondrocytes, and a greater abundance of fibroblasts. The enthesis reveals longitudinal and interwoven collagen bundles entering the proximal phalanx with multiple interdigitations. Longer interdigitations centrally compared to the dorsal and plantar aspects suggest that the central fibers experience the greatest loads.

  7. Ultrasound elastography in the early diagnosis of plantar fasciitis.

    PubMed

    Lee, So-Yeon; Park, Hee Jin; Kwag, Hyon Joo; Hong, Hyun-Pyo; Park, Hae-Won; Lee, Yong-Rae; Yoon, Kyung Jae; Lee, Yong-Taek

    2014-01-01

    The purpose of this study was to investigate whether ultrasound (US) elastography is useful for the early diagnosis of plantar fasciitis. We retrospectively reviewed US elastography findings of 18 feet with a clinical history and physical examination highly suggestive of plantar fasciitis but with normal findings on conventional US imaging as well as 18 asymptomatic feet. Softening of the plantar fascia was significantly greater in the patient than in the control group [Reviewers 1 and 2: 89% (16/18) vs. 50% (9/18), P=.027, respectively]. US elastography is useful for the early diagnosis of plantar fasciitis. Copyright © 2014 Elsevier Inc. All rights reserved.

  8. ACL Fibers Near the Lateral Intercondylar Ridge Are the Most Load Bearing During Stability Examinations and Isometric Through Passive Flexion.

    PubMed

    Nawabi, Danyal H; Tucker, Scott; Schafer, Kevin A; Zuiderbaan, Hendrik Aernout; Nguyen, Joseph T; Wickiewicz, Thomas L; Imhauser, Carl W; Pearle, Andrew D

    2016-10-01

    The femoral insertion of the anterior cruciate ligament (ACL) has direct and indirect fiber types located within the respective high (anterior) and low (posterior) regions of the femoral footprint. The fibers in the high region of the ACL footprint carry more force and are more isometric than the fibers in the low region of the ACL footprint. Controlled laboratory study. Ten fresh-frozen cadaveric knees were mounted to a robotic manipulator. A 134-N anterior force at 30° and 90° of flexion and combined valgus (8 N·m) and internal (4 N·m) rotation torques at 15° of flexion were applied simulating tests of anterior and rotatory stability. The ACL was sectioned at the femoral footprint by detaching either the higher band of fibers neighboring the lateral intercondylar ridge in the region of the direct insertion or the posterior, crescent-shaped fibers in the region of the indirect insertion, followed by the remainder of the ACL. The kinematics of the ACL-intact knee was replayed, and the reduction in force due to each sectioned portion of insertion fibers was measured. Isometry was assessed at anteromedial, center, and posterolateral locations within the high and low regions of the femoral footprint. With an anterior tibial force at 30° of flexion, the high fibers carried 83.9% of the total anterior ACL load compared with 16.1% in the low fibers (P < .001). The high fibers also carried more anterior force than the low fibers at 90° of flexion (95.2% vs 4.8%; P < .001). Under combined torques at 15° of flexion, the high fibers carried 84.2% of the anterior ACL force compared with 15.8% in the low fibers (P < .001). Virtual ACL fibers placed at the anteromedial portion of the high region of the femoral footprint were the most isometric, with a maximum length change of 3.9 ± 1.5 mm. ACL fibers located high within the femoral footprint bear more force during stability testing and are more isometric during flexion than low fibers. It may be advantageous to create

  9. Instantaneous centers of rotation in dorsi/plantar flexion movements of posterior-type plastic ankle-foot orthoses.

    PubMed

    Sumiya, T; Suzuki, Y; Kasahara, T; Ogata, H

    1997-07-01

    Hingeless plastic ankle-foot orthoses (PAFOs) achieve ankle motion by flexing about the ankle joint. Instantaneous centers of rotation (ICRs) in dorsi- and plantarflexion movements, used as a measure of PAFO axes of movement, were measured to evaluate their fit to ankle motion. Thirty different PAFOs were fabricated and their stiffness modified in three stages. They were dorsi- and plantarflexed 16 degrees at 2 degrees-intervals using an original device. Displacement of two marks on the lateral calf-cuff were traced photographically, and ICRs were determined by plotting intersections of vertical bisectors for each displacement. The ICRs converged on the junction between the calf shell and the shoe insert. They deviated posteriorly from the anatomical ankle axis and caused the calf-cuff to move up-down during dorsi- and plantarflexion movements. However, this poor fit of the PAFO to ankle motion can be sufficiently compensated for by fastening straps more loosely.

  10. Recruitment and rate coding organisation for soleus motor units across entire range of voluntary isometric plantar flexions.

    PubMed

    Oya, Tomomichi; Riek, Stephan; Cresswell, Andrew G

    2009-10-01

    Unlike upper limb muscles, it remains undocumented as to how motor units in the soleus muscle are organised in terms of recruitment range and discharge rates with respect to their recruitment and de-recruitment thresholds. The possible influence of neuromodulation, such as persistent inward currents (PICs) on lower limb motor unit recruitment and discharge rates has also yet to be reported. To address these issues, electromyographic (EMG) activities from the soleus muscle were recorded using selective branched-wire intramuscular electrodes during ramp-and-hold contractions with intensities up to maximal voluntary contraction (MVC). The multiple single motor unit activities were then derived using a decomposition technique. The onset-offset hysteresis of motor unit discharge, i.e. a difference between recruitment and de-recruitment thresholds, as well as PIC magnitude calculated by a paired motor unit analysis were used to examine the neuromodulatory effects on discharge behaviours, such as minimum firing rate, peak firing rate and degree of increase in firing rate. Forty-two clearly identified motor units from five subjects revealed that soleus motor units are recruited progressively from rest to contraction strengths close to 95% of MVC, with low-threshold motor units discharging action potentials slower at their recruitment and with a lower peak rate than later recruited high-threshold units. This observation is in contrast to the 'onion skin phenomenon' often reported for the upper limb muscles. Based on positive correlations of the peak discharge rates, initial rates and recruitment order of the units with the magnitude of the onset-offset hysteresis and not PIC contribution, we conclude that discharge behaviours among motor units appear to be related to a variation in an intrinsic property other than PICs.

  11. Endoscopic Plantar Fasciotomy vs Open Radiofrequency Microtenotomy for Recalcitrant Plantar Fasciitis.

    PubMed

    Wang, Weining; Rikhraj, Inderjeet Singh; Chou, Andrew Chia Chen; Chong, Hwei Chi; Koo, Kevin Oon Thien

    2018-01-01

    Although usually self-limiting, around 10% of patients develop recalcitrant plantar fasciitis despite conservative treatment. In such cases, operative intervention can be offered. Traditionally, plantar fasciotomy has been the treatment of choice, but recently, there has been a push for more minimally invasive approaches. Radiofrequency microtenotomy has also been increasingly used as a treatment option. In this study, we compare the outcomes of endoscopic plantar fasciotomy and open radiofrequency microtenotomy. Patients treated in our institution with either procedure between 2007 and 2015 were included and interviewed at baseline and 3 months, 6 months, and 12 months postoperatively using the American Orthopaedic Foot & Ankle Society (AOFAS) and 36-item Medical Outcomes Short Form (SF-36) questionnaires. They were asked questions to evaluate their expectation and satisfaction postoperatively. Demographic and clinicopathological data were prospectively collected from clinical charts and electronic records. There was no difference in either treatment arms preoperatively and an overall improvement in all functional outcomes postoperatively. However, patients who had endoscopic plantar fasciotomy fared better at 3 months compared to patients who underwent open microtenotomy with the visual analog score component of the AOFAS hindfoot score (HINDVAS) and the social functioning and role-functioning-emotional reaching statistical significance ( P = .027, P = .03, and P = .03, respectively). There was no difference in functional outcomes at 6 or 12 months postoperatively. Endoscopic plantar fasciotomy was associated with an earlier improvement in functional outcome in our study. However, both treatments had equivalent outcomes at 1-year follow-up, suggesting that either method is reasonable in the treatment of chronic plantar fasciitis. Level III, comparative study.

  12. Test-retest reliability of cardinal plane isokinetic hip torque and EMG.

    PubMed

    Claiborne, Tina L; Timmons, Mark K; Pincivero, Danny M

    2009-10-01

    The objective of the present study was to establish test-retest reliability of isokinetic hip torque and prime mover electromyogram (EMG) through the three cardinal planes of motion. Thirteen healthy young adults participated in two experimental sessions, separated by approximately one week. During each session, isokinetic hip torque was evaluated on the Biodex Isokinetic Dynamometer at a velocity of 60 deg/s. Subjects performed three maximal-effort concentric and eccentric contractions, separately, for right and left hip abduction/adduction, flexion/extension, and internal/external rotation. Surface EMGs were sampled from the gluteus maximus, gluteus medius, adductor, medial and lateral hamstring, and rectus femoris muscles during all contractions. Intraclass correlation coefficients (ICC - 2,1) and standard errors of measurement (SEM) were calculated for peak torque for each movement direction and contraction mode, while ICCs were only computed for the EMG data. Motions that demonstrated high torque reliability included concentric hip abduction (right and left), flexion (right and left), extension (right) and internal rotation (right and left), and eccentric hip abduction (left), adduction (left), flexion (right), and extension (right and left) (ICC range=0.81-0.91). Motions with moderate torque reliability included concentric hip adduction (right), extension (left), internal rotation (left), and external rotation (right), and eccentric hip abduction and adduction (right), flexion (left), internal rotation (right and left), and external rotation (right and left) (ICC range=0.49-0.79). The majority of the EMG sampled muscles (n=12 and n=11 for concentric and eccentric contractions, respectively) demonstrated high reliability (ICC=0.81-0.95). Instances of low, or unacceptable, EMG reliability values occurred for the medial hamstring muscle of the left leg (both contraction modes) and the adductor muscle of the right leg during eccentric internal rotation. The major

  13. Deformable micro torque swimmer

    NASA Astrophysics Data System (ADS)

    Ishikawa, Takuji; Tanaka, Tomoyuki; Omori, Toshihiro; Imai, Yohsuke

    2015-11-01

    We investigated the deformation of a ciliate swimming freely in a fluid otherwise at rest. The cell body was modeled as a capsule with a hyper elastic membrane enclosing Newtonian fluid. Thrust forces due to the ciliary beat were modeled as torques distributed above the cell body. Effects of the membrane elasticity, the aspect ratio of cell's reference shape and the density difference between the cell and the surrounding fluid were investigated. The results showed that the cell deformed like heart shape when Capillary number (Ca) was sufficiently large, and the swimming velocity decreased as Ca was increased. The gravity effect on the membrane tension suggested that the upwards and downwards swimming velocities of Paramecium might be reglated by the calcium ion channels distributed locally around the anterior end. Moreover, the gravity induced deformation made a cell directed vertically downwards, which resulted in a positive geotaxis like behavior with physical origin. These results are important to understand physiology of ciliate's biological responses to mechanical stimuli.

  14. Quick torque coupling

    DOEpatents

    Luft, Peter A [El Cerrito, CA

    2009-05-12

    A coupling for mechanically connecting modular tubular struts of a positioning apparatus or space frame, comprising a pair of toothed rings (10, 12) attached to separate strut members (16), the teeth (18, 20) of the primary rings (10, 12) mechanically interlocking in both an axial and circumferential manner, and a third part comprising a sliding, toothed collar (14) the teeth (22) of which interlock the teeth (18, 20) of the primary rings (10, 12), preventing them from disengaging, and completely locking the assembly together. A secondary mechanism provides a nesting force for the collar, and/or retains it. The coupling is self-contained and requires no external tools for installation, and can be assembled with gloved hands in demanding environments. No gauging or measured torque is required for assembly. The assembly can easily be visually inspected to determine a "go" or "no-go" status. The coupling is compact and relatively light-weight. Because of it's triply interlocking teeth, the connection is rigid. The connection does not primarily rely on clamps, springs or friction based fasteners, and is therefore reliable in fail-safe applications.

  15. Effect of Ankle Positioning During Hamstring Stretches for Improving Straight Leg Hip Flexion Motion.

    PubMed

    Laudner, Kevin G; Benjamin, Peter J; Selkow, Noelle M

    2016-03-01

    To compare the effects of stretching the hamstrings with the ankle in either a plantar-flexed (PF) or dorsiflexed (DF) position for improving straight leg hip flexion range of motion (ROM) over a 4-week period. Randomized, single-blinded, pretest, posttest design. Athletic training facility. Each limb of 34 asymptomatic individuals (15 males, 19 females) was randomly assigned to one of the 3 groups. Twenty-four limbs received hamstring stretches with the ankle in DF, 24 limbs received hamstring stretches with the ankle in PF, and 20 limbs received no stretch (control). Ankle position (PF, DF) during hamstring stretching. We measured pretest and posttest passive straight leg hip flexion ROM with the test ankle in a neutral position. For the intervention groups, the test limb was passively stretched with the ankle held in end range DF or PF for their respective group. Each stretch was held for 30 seconds for a total of 3 applications. Two treatment sessions were completed per week for a total of 4 weeks. The control limbs received no stretching during the 4-week period. We conducted 1-way analyses of covariance to determine significant changes in ROM between groups (P < 0.05). There was no significant difference between treatment groups (P = 0.90), but a significant difference was found for both the PF (P = 0.04) and DF (P = 0.01) groups when compared with the control group. Our findings indicate that both stretching the hamstrings in either PF or DF improve straight leg hip ROM compared with a control group. The results of this study should be considered by clinicians when determining the optimal stretching techniques aimed at increasing hamstring length.

  16. Plantar-to-dorsal compared to dorsal-to-plantar screw fixation for proximal chevron osteotomy: a biomechanical analysis.

    PubMed

    Sharma, Krishn M; Parks, Brent G; Nguyen, Augustine; Schon, Lew C

    2005-10-01

    A change in screw orientation in fixing the chevron proximal first metatarsal osteotomy was noted anecdotally to improve fixation strength. The authors hypothesized that plantar-to-dorsal screw orientation would be more stable than the conventional dorsal-to-plantar screw orientation for fixation of the chevron osteotomy. The purpose of this study was to determine if the load-to-failure and stiffness of the chevron type proximal first metatarsal osteotomy stabilized using plantar-to-dorsal screw fixation were greater than with the more conventional dorsal-to-plantar screw fixation method. One foot from each of eight matched cadaver pairs was randomly assigned to one of two groups: 1) fixation with a dorsal-to-plantar lag screw or 2) fixation with a plantar-to-dorsal lag screw. A proximal chevron osteotomy was then created using standard technique and the metatarsal was fixed according to previously established method. The bone was potted in polyester resin, and the construct was fitted into a materials testing system machine in which load was applied to the plantar aspect of the metatarsal until failure. The two groups were compared using a two-tailed Student t test. The average load-to-failure and stiffness of the chevron osteotomy fixed with the plantar-to-dorsal lag screw were significantly greater (p < 0.05) than the group fixed with more conventional dorsal-to-plantar lag screws. Plantar-to-dorsal screw orientation was more stable than the conventional dorsal-to-plantar screw orientation for fixation of the proximal chevron osteotomy. Plantar-to-dorsal screw orientation should be considered when using the chevron proximal first metatarsal osteotomy.

  17. Zero torque gear head wrench

    NASA Technical Reports Server (NTRS)

    Mcdougal, A. R.; Norman, R. M. (Inventor)

    1976-01-01

    A gear head wrench particularly suited for use in applying torque to bolts without transferring torsional stress to bolt-receiving structures is introduced. The wrench is characterized by a coupling including a socket, for connecting a bolt head with a torque multiplying gear train, provided within a housing having an annulus concentrically related to the socket and adapted to be coupled with a spacer interposed between the bolt head and the juxtaposed surface of the bolt-receiving structure for applying a balancing counter-torque to the spacer as torque is applied to the bolt head whereby the bolt-receiving structure is substantially isolated from torsional stress. As a result of the foregoing, the operator of the wrench is substantially isolated from any forces which may be imposed.

  18. Thermomagnetic torques in polyatomic gases

    NASA Technical Reports Server (NTRS)

    Hildebrandt, A. F.; Wood, C. T.

    1972-01-01

    The application of the Scott effect to the dynamics of galactic and stellar rotation is investigated. Efforts were also made to improve the sensitivity and stability of torque measurements and understand the microscopic mechanism that causes the Scott effect.

  19. Association between plantar fascia vascularity and morphology and foot dysfunction in individuals with chronic plantar fasciitis.

    PubMed

    Chen, Hongying; Ho, Hok-Ming; Ying, Michael; Fu, Siu Ngor

    2013-10-01

    Single-cohort laboratory-based study. To identify whether plantar fascia vascularity and thickness are associated with foot pain and dysfunction in individuals with chronic plantar fasciitis. Background Altered plantar fascia vascularity and thickening of the fascia have been identified in individuals with chronic plantar fasciitis. Thirty-eight patients with chronic unilateral plantar fasciitis and 21 controls participated in this study. Proximal plantar fascia vascularization and thickness were assessed using ultrasound imaging, and pain and foot dysfunction were quantified with a visual analog scale and the Chinese version of the Foot Function Index, respectively. Paired t tests were used to assess the side-to-side differences in fascia thickness and vascularity index (VI) in the control and patient groups, and an unpaired t test was used to make comparisons with the patient group. Multiple regression analysis was performed to identify whether the VI and fascia thickness were associated with pain and foot dysfunction. There were significantly higher VI (mean ± SD, 2.4% ± 1.4%) and fascia thickness (5.0 ± 1.3 mm) values in the affected feet when compared with the unaffected feet in the patient group (VI, 1.4% ± 0.5%; fascia thickness, 3.3 ± 0.7 mm) and with the dominant side of the controls (VI, 1.6% ± 0.4%; fascia thickness, 2.9 ± 0.6 mm). After accounting for age, gender, body mass index, and duration of symptoms, the VI explained 13% and 33% of the variance in pain scores measured with a visual analog scale and the pain subscale of the Foot Function Index, respectively; the VI and fascia thickness explained 42% of the variance in the Foot Function Index. Individuals with unilateral chronic plantar fasciitis demonstrated significantly greater vascularity and thickened fascia on the affected side compared to the unaffected side and also to healthy controls. Fascia vascularity was associated independently with self-perceived pain, and both fascia

  20. 14 CFR 27.361 - Engine torque.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 14 Aeronautics and Space 1 2014-01-01 2014-01-01 false Engine torque. 27.361 Section 27.361... STANDARDS: NORMAL CATEGORY ROTORCRAFT Strength Requirements Flight Loads § 27.361 Engine torque. (a) For turbine engines, the limit torque may not be less than the highest of— (1) The mean torque for maximum...

  1. 14 CFR 27.361 - Engine torque.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 14 Aeronautics and Space 1 2013-01-01 2013-01-01 false Engine torque. 27.361 Section 27.361... STANDARDS: NORMAL CATEGORY ROTORCRAFT Strength Requirements Flight Loads § 27.361 Engine torque. (a) For turbine engines, the limit torque may not be less than the highest of— (1) The mean torque for maximum...

  2. 14 CFR 27.361 - Engine torque.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 14 Aeronautics and Space 1 2011-01-01 2011-01-01 false Engine torque. 27.361 Section 27.361... STANDARDS: NORMAL CATEGORY ROTORCRAFT Strength Requirements Flight Loads § 27.361 Engine torque. (a) For turbine engines, the limit torque may not be less than the highest of— (1) The mean torque for maximum...

  3. 14 CFR 27.361 - Engine torque.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 14 Aeronautics and Space 1 2012-01-01 2012-01-01 false Engine torque. 27.361 Section 27.361... STANDARDS: NORMAL CATEGORY ROTORCRAFT Strength Requirements Flight Loads § 27.361 Engine torque. (a) For turbine engines, the limit torque may not be less than the highest of— (1) The mean torque for maximum...

  4. 14 CFR 27.361 - Engine torque.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 14 Aeronautics and Space 1 2010-01-01 2010-01-01 false Engine torque. 27.361 Section 27.361... STANDARDS: NORMAL CATEGORY ROTORCRAFT Strength Requirements Flight Loads § 27.361 Engine torque. (a) For turbine engines, the limit torque may not be less than the highest of— (1) The mean torque for maximum...

  5. Torque-Summing Brushless Motor

    NASA Technical Reports Server (NTRS)

    Vaidya, J. G.

    1986-01-01

    Torque channels function cooperatively but electrically independent for reliability. Brushless, electronically-commutated dc motor sums electromagnetic torques on four channels and applies them to single shaft. Motor operates with any combination of channels and continues if one or more of channels fail electrically. Motor employs single stator and rotor and mechanically simple; however, each of channels electrically isolated from other so that failure of one does not adversely affect others.

  6. Relationship of Plantar Fascia Thickness and Preoperative Pain, Function, and Quality of Life in Recalcitrant Plantar Fasciitis.

    PubMed

    Gamba, Carlo; Sala-Pujals, Aleix; Perez-Prieto, Daniel; Ares-Vidal, Jesus; Solano-Lopez, Alberto; Gonzalez-Lucena, Gemma; Ginés-Caspedosa, Alberto

    2018-04-01

    The measurement of plantar fascia thickness has been advocated as a diagnostic and prognostic instrument in patients with plantar fasciitis, but there are no data relative to it in recalcitrant plantar fasciitis. The aim of the study is to evaluate the correlation between plantar fascia thickness and pain, functional score, and health perception in patients with this condition. Thirty-eight feet were studied with ultrasound and magnetic resonance imaging to measure plantar fascia thickness. The visual analogue scale (VAS), American Orthopaedic Foot & Ankle Hindfoot Score (AOFAS), and SF-36 were then recorded for each patient. The relationship between the fascia and these scores was analyzed to evaluate the correlation of thickness with pain, functional level, and health perception of patients. In patients with recalcitrant plantar fasciitis, plantar fascia thickness did not correlate with pain (VAS), AOFAS, or any item of the SF-36. The thickness of the plantar fascia in patients with recalcitrant plantar fasciitis did not correlate with its clinical impact, and thus, we believe it should not be used in treatment planning. Level IV, case series.

  7. Plantar fasciitis (fasciosis) treatment outcome study: plantar fascia thickness measured by ultrasound and correlated with patient self-reported improvement.

    PubMed

    Fabrikant, Jerry M; Park, Tae Soon

    2011-06-01

    Ultrasound, well recognized as an effective diagnostic tool, reveals a thickening of the plantar fascia in patients with plantar fasciitis/fasciosis disease. The authors hypothesized that ultrasound would also reveal a decrease in the plantar fascia thickness for patients undergoing treatment for the disease, a hypothesis that, heretofore, had been only tested on a limited number of subjects. They conducted a more statistically significant study that found that clinical treatment with injection and biomechanical correction does indeed diminish plantar fascia thickness as shown on ultrasound. The study also revealed that patients experience the most heightened plantar fascia tenderness toward the end of the day, and improvement in their symptomatic complaints were associated with a reduction in plantar fascia thickness. As a result, the authors conclude that office-based ultrasound can help diagnose and confirm plantar fasciitis/fasciosis through the measurement of the plantar fascia thickness. Because of the advantages of ultrasound--that it is non-invasive with greater patient acceptance, cost effective and radiation-free--the imaging tool should be considered and implemented early in the diagnosis and treatment of plantar fasciitis/fasciosis. Copyright © 2011 Elsevier Ltd. All rights reserved.

  8. Moment arms of the human neck muscles in flexion, bending and rotation.

    PubMed

    Ackland, David C; Merritt, Jonathan S; Pandy, Marcus G

    2011-02-03

    There is a paucity of data available for the moment arms of the muscles of the human neck. The objective of the present study was to measure the moment arms of the major cervical spine muscles in vitro. Experiments were performed on five fresh-frozen human head-neck specimens using a custom-designed robotic spine testing apparatus. The testing apparatus replicated flexion-extension, lateral bending and axial rotation of each individual intervertebral joint in the cervical spine while all other joints were kept immobile. The tendon excursion method was used to measure the moment arms of 30 muscle sub-regions involving 13 major muscles of the neck about all three axes of rotation of each joint for the neutral position of the cervical spine. Significant differences in the moment arm were observed across sub-regions of individual muscles and across the intervertebral joints spanned by each muscle (p<0.05). Overall, muscle moment arms were larger in flexion-extension and lateral bending than in axial rotation, and most muscles had prominent moment arms in at least 2 out of the 3 joint motions investigated. This study emphasizes the importance of detailed representation of a muscle's architecture in prediction of its torque capacity about the individual joints of the cervical spine. The dataset produced may be useful in developing and validating computational models of the human neck. Copyright © 2010 Elsevier Ltd. All rights reserved.

  9. Information theoretic analysis of proprioceptive encoding during finger flexion in the monkey sensorimotor system.

    PubMed

    Witham, Claire L; Baker, Stuart N

    2015-01-01

    There is considerable debate over whether the brain codes information using neural firing rate or the fine-grained structure of spike timing. We investigated this issue in spike discharge recorded from single units in the sensorimotor cortex, deep cerebellar nuclei, and dorsal root ganglia in macaque monkeys trained to perform a finger flexion task. The task required flexion to four different displacements against two opposing torques; the eight possible conditions were randomly interleaved. We used information theory to assess coding of task condition in spike rate, discharge irregularity, and spectral power in the 15- to 25-Hz band during the period of steady holding. All three measures coded task information in all areas tested. Information coding was most often independent between irregularity and 15-25 Hz power (60% of units), moderately redundant between spike rate and irregularity (56% of units redundant), and highly redundant between spike rate and power (93%). Most simultaneously recorded unit pairs coded using the same measure independently (86%). Knowledge of two measures often provided extra information about task, compared with knowledge of only one alone. We conclude that sensorimotor systems use both rate and temporal codes to represent information about a finger movement task. As well as offering insights into neural coding, this work suggests that incorporating spike irregularity into algorithms used for brain-machine interfaces could improve decoding accuracy. Copyright © 2015 the American Physiological Society.

  10. Pressurized fluid torque driver control and method

    NASA Technical Reports Server (NTRS)

    Cook, Joseph S., Jr. (Inventor)

    1994-01-01

    Methods and apparatus are provided for a torque driver including a displaceable gear to limit torque transfer to a fastener at a precisely controlled torque limit. A biasing assembly biases a first gear into engagement with a second gear for torque transfer between the first and second gear. The biasing assembly includes a pressurized cylinder controlled at a constant pressure that corresponds to a torque limit. A calibrated gage and valve is used to set the desired torque limit. One or more coiled output linkages connect the first gear with the fastener adaptor which may be a socket for a nut. A gear tooth profile provides a separation force that overcomes the bias to limit torque at the desired torque limit. Multiple fasteners may be rotated simultaneously to a desired torque limit if additional output spur gears are provided. The torque limit is adjustable and may be different for fasteners within the same fastener configuration.

  11. Effect of surgical closing in total knee arthroplasty at flexion or extension: a prospective, randomized study.

    PubMed

    Kömürcü, Erkam; Yüksel, Halil Yalçın; Ersöz, Murat; Aktekin, Cem Nuri; Hapa, Onur; Çelebi, Levent; Akbal, Ayla; Biçimoğlu, Ali

    2014-12-01

    The aim of this study was to evaluate the effect of knee position during wound closure (flexed vs. extended) in total knee arthroplasty on knee strength and function, as determined by knee society scores and isokinetic testing of extensor and flexor muscle groups. In a prospective, randomized, double-blind trial, 29 patients were divided in two groups: for Group 1 patients, surgical closing was performed with the knee extended, and for Group 2 patients, the knee flexed at 90°. All the patients were treated with the same anaesthesia method, surgical team, surgical technique, prosthesis type, and rehabilitation process. American Knee Society Score values and knee flexion degrees were recorded. Isokinetic muscle strength measurements of both knees in flexion and extension were taken using 60° and 180°/s angular velocity. The peak torque and total work values, isokinetic muscle strength differences, and total work difference values were calculated for surgically repaired and healthy knees. No significant difference in the mean American Knee Society Score values and knee flexion degrees was observed between the two groups. However, using isokinetic evaluation, a significant difference was found in the isokinetic muscle strength differences and total work difference of the flexor muscle between the two groups when patients were tested at 180°/s. Less loss of strength was detected in the isokinetic muscle strength differences of the flexor muscle in Group 2 (-4.2%) than in Group 1 (-23.1%). For patients undergoing total knee arthroplasty, post-operative flexor muscle strength is improved if the knee is flexed during wound closure. II.

  12. America’s Cup Sailing: Effect of Standing Arm-Cranking (“Grinding”) Direction on Muscle Activity, Kinematics, and Torque Application

    PubMed Central

    Pearson, Simon N.; Hume, Patria A.; Cronin, John; Slyfield, David

    2016-01-01

    Grinding is a key physical element in America’s Cup sailing. This study aimed to describe kinematics and muscle activation patterns in relation to torque applied in forward and backward grinding. Ten male America’s Cup sailors (33.6 ± 5.7 years, 97.9 ± 13.4 kg, 186.6 ± 7.4 cm) completed forward and backward grinding on a customised grinding ergometer. In forward grinding peak torque (77 Nm) occurred at 95° (0° = crank vertically up) on the downward section of the rotation at the end of shoulder flexion and elbow extension. Backward grinding torque peaked at 35° (69 Nm) following the pull action (shoulder extension, elbow flexion) across the top of the rotation. During forward grinding, relatively high levels of torque (>50 Nm) were maintained through the majority (72%) of the cycle, compared to 47% for backward grinding, with sections of low torque corresponding with low numbers of active muscles. Variation in torque was negatively associated with forward grinding performance (r = −0.60; 90% CI −0.88 to −0.02), but positively associated with backward performance (r = 0.48; CI = −0.15 to 0.83). Magnitude and distribution of torque generation differed according to grinding direction and presents an argument for divergent training methods to improve forward and backward grinding performance.

  13. Femoral neck radiography: effect of flexion on visualization.

    PubMed

    Garry, Steven C; Jhangri, Gian S; Lambert, Robert G W

    2005-06-01

    To determine whether flexion improves radiographic visualization of the femoral neck when the femur is externally rotated. Five human femora, with varying neck-shaft and anteversion angles, were measured and immobilized. Degree of flexion required to bring the femoral neck horizontal was measured, varying the rotation. Next, one bone was radiographed in 16 positions, varying rotation in 15 degrees and flexion in 10 degrees increments. Radiographs were presented in randomized blinded fashion to 15 staff radiologists for scoring of femoral neck visualization. Following this, all 5 bones were radiographed in 4 positions of rotation and at 0 degree and 20 degrees flexion, and blinded randomized review of radiographs was repeated. Comparisons between angles and rotations were made using the Mann-Whitney test. The flexion angle required to bring the long axis of the femoral neck horizontal correlated directly with the degree of external rotation (p < 0.05). Visualization of the femoral neck in the extended position progressively deteriorated from 15 degrees internal rotation to 30 degrees external rotation (p < 0.01). However, when 20 degrees flexion was applied to bones in external rotation, visualization significantly improved at 15 degrees (p < 0.05) and 30 degrees (p < 0.01). Flexion of the externally rotated femur can bring the femoral neck into horizontal alignment, and a relatively small amount (20 degrees) of flexion can significantly improve radiographic visualization. This manoeuvre could be useful for radiography of the femoral neck when initial radiographs are inadequate because of external rotation of the leg.

  14. Flexion Reflex Can Interrupt and Reset the Swimming Rhythm.

    PubMed

    Elson, Matthew S; Berkowitz, Ari

    2016-03-02

    The spinal cord can generate the hip flexor nerve activity underlying leg withdrawal (flexion reflex) and the rhythmic, alternating hip flexor and extensor activities underlying locomotion and scratching, even in the absence of brain inputs and movement-related sensory feedback. It has been hypothesized that a common set of spinal interneurons mediates flexion reflex and the flexion components of locomotion and scratching. Leg cutaneous stimuli that evoke flexion reflex can alter the timing of (i.e., reset) cat walking and turtle scratching rhythms; in addition, reflex responses to leg cutaneous stimuli can be modified during cat and human walking and turtle scratching. Both of these effects depend on the phase (flexion or extension) of the rhythm in which the stimuli occur. However, similar interactions between leg flexion reflex and swimming have not been reported. We show here that a tap to the foot interrupted and reset the rhythm of forward swimming in spinal, immobilized turtles if the tap occurred during the swim hip extensor phase. In addition, the hip flexor nerve response to an electrical foot stimulus was reduced or eliminated during the swim hip extensor phase. These two phase-dependent effects of flexion reflex on the swim rhythm and vice versa together demonstrate that the flexion reflex spinal circuit shares key components with or has strong interactions with the swimming spinal network, as has been shown previously for cat walking and turtle scratching. Therefore, leg flexion reflex circuits likely share key spinal interneurons with locomotion and scratching networks across limbed vertebrates generally. The spinal cord can generate leg withdrawal (flexion reflex), locomotion, and scratching in limbed vertebrates. It has been hypothesized that there is a common set of spinal cord neurons that produce hip flexion during flexion reflex, locomotion, and scratching based on evidence from studies of cat and human walking and turtle scratching. We show

  15. Eccentric Torque-Producing Capacity is Influenced by Muscle Length in Older Healthy Adults.

    PubMed

    Melo, Ruth C; Takahashi, Anielle C M; Quitério, Robison J; Salvini, Tânia F; Catai, Aparecida M

    2016-01-01

    Considering the importance of muscle strength to functional capacity in the elderly, the study investigated the effects of age on isokinetic performance and torque production as a function of muscle length. Eleven younger (24.2 ± 2.9 years) and 16 older men (62.7 ± 2.5 years) were subjected to concentric and eccentric isokinetic knee extension/flexion at 60 and 120° · s(-1) through a functional range of motion. The older group presented lower peak torque (in newton-meters) than the young group for both isokinetic contraction types (age effect, p < 0.001). Peak torque deficits in the older group were near 30 and 29% for concentric and eccentric contraction, respectively. Concentric peak torque was lower at 120° · s(-1) than at 60° · s(-1) for both groups (angular velocity effect, p < 0.001). Eccentric knee extension torque was the only exercise tested that showed an interaction effect between age and muscle length (p < 0.001), which suggested different torque responses to the muscle length between groups. Compared with the young group, the eccentric knee extension torque was 22-56% lower in the older group, with the deficits being lower in the shortened muscle length (22-27%) and higher (33-56%) in the stretched muscle length. In older men, the production of eccentric knee strength seems to be dependent on the muscle length. At more stretched positions, older subjects lose the capacity to generate eccentric knee extension torque. More studies are needed to assess the mechanisms involved in eccentric strength preservation with aging and its relationship with muscle length.

  16. Plantar fascia calcification a sequelae of corticosteroid injection in the treatment of recalcitrant plantar fasciitis.

    PubMed

    Fox, Thomas Peter; Oliver, Govind; Wek, Caesar; Hester, Thomas

    2013-08-16

    We report the case of a 72-year-old woman suffering with severe plantar fasciitis who received a therapeutic corticosteroid injection. Two-and-a-half years after the injection she developed a small calcified lump under the skin which subsequently caused ulceration and infection. She went on to develop a diabetic foot infection requiring an extended course of intravenous antibiotics.

  17. [Assessment of plantar fasciitis using shear wave elastography].

    PubMed

    Zhang, Lining; Wan, Wenbo; Zhang, Lihai; Xiao, Hongyu; Luo, Yukun; Fei, Xiang; Zheng, Zhixin; Tang, Peifu

    2014-02-01

    To assess the stiffness and thickness of the plantar fascia using shear wave elastography (SWE) in healthy volunteers of different ages and in patients with plantar fasciitis. The bilateral feet of 30 healthy volunteers and 23 patients with plantar fasciitis were examined with SWE. The plantar fascia thickness and elasticity modulus value were measured at the insertion of the calcaneus and at 1 cm from the insertion. The elderly volunteers had a significantly greater plantar fascia thickness measured using conventional ultrasound (P=0.005) and a significantly lower elasticity modulus value than the young volunteers (P=0.000). The patients with fasciitis had a significantly greater plantar fascia thickness (P=0.001) and a lower elasticity modulus value than the elderly volunteers (P=0.000). The elasticity modulus value was significantly lower at the calcaneus insertion than at 1 cm from the insertion in patients with fasciitis (P=0.000) but showed no significantly difference between the two points in the elderly or young volunteers (P=0.172, P=0.126). SWE allows quantitative assessment of the stiffness of the plantar fascia, which decreases with aging and in patients with plantar fasciitis.

  18. Influence of shoes increasing dorsiflexion and decreasing metatarsus flexion on lower limb muscular activity during fitness exercises, walking, and running.

    PubMed

    Bourgit, David; Millet, Guillaume Y; Fuchslocher, Jörg

    2008-05-01

    The aim of the present study was to compare electromyographic activity during fitness exercises, walking, and running among 3 different dorsiflexion shoes (+2 degrees , +4 degrees , and +10 degrees ) and standard shoes (-4 degrees ). The 3 different dorsiflexion shoes tested in this study have a curvature placed in the middle of the sole. This design was specially projected to decrease the metatarsus flexion. Electromyographic activity of 9 lower limb muscles was measured on 12 healthy female subjects during 5 fitness exercises (unload squat, side and front step, submaximal ballistic plantar flexion, and lunge exercise), and during running (10 km x h(-1)) and walking (4.5 km x h(-1)) on a treadmill. EMG signal was analyzed with the root mean square (RMS) and integrated EMG. All RMS data measured during these exercises were expressed as percentages of maximum voluntary isometric contraction. The results show that dorsiflexion affects muscle recruitment and reorganizes the motor pattern. The general tendency was that the tibialis anterior activity increased with dorsiflexion. However, an optimal dorsiflexion existed for various exercises. It is concluded that shoes with moderate dorsiflexion can activate lower limb muscles differently compared with both standard shoes and shoes with large dorsiflexion during submaximal exercises and locomotion.

  19. The Mysterious Southern Torque

    NASA Astrophysics Data System (ADS)

    McDowell, M. S.

    2004-05-01

    Something weird happened to twist the southern hemisphere out of alignment with the northern, as evidenced by the positions of the mountain ranges of North and South America, the Atlantic MAR, and the closure of West Africa to North America - all smooth were the torque reversed. What happened, and when, and why? We identify a number of global "cracks" of almost exactly the same length and direction, with some, even more peculiarly, turning the same angle, and proceeding an equal distance in the new direction. The Emperor-Hawaiian chain, the Louisville chain and the west coast of North America, as examples, are essentially parallel. Their northerly legs follow the angle of the axis of orbital ellipse. But then they all make equal 45 degree easterly bends, to 17.5 NW, and continue on, still parallel, for very similar distances. It is the same at the north coast of South America, and the mid-section of the MAR from 46W to 12W. It is the distance from the Cameroons to Kenya, from the south end of the Red Sea to the SE Indian Ridge at the Nema Fracture zone, from west to east of the Nazca plate.What is all this? Coincidence? Seeing things? Researchers have attributed plate motion or hot spot motion or both or absolutely none, to all of the above. Geophysicists have dated the surfaces from Archean to Pleistocene by all possible scientific means, certainly no possible correlation can be made. Yet we postulate the physical reality can be demonstrated. It is so global a phenomenon that it is well beyond what a hot spot or a plate could do. Even a really tremendous impact would have trouble making such precise geometric arrangements. So what is it - perhaps the angle of rotation, or the inertia of northern hemisphere mass above the geoid? And if so, then, what changed it? It would seem that some huge imbalance occurred. Suppose the whole bottom blew out of the southern hemisphere, and the center of mass drastically altered. Suppose some unknown universal force changed our

  20. Plantar fasciitis and its relationship with hallux limitus.

    PubMed

    Aranda, Yolanda; Munuera, Pedro V

    2014-05-01

    We sought to determine whether patients with plantar fasciitis have limited dorsiflexion in the first metatarsophalangeal joint and which type of foot, pronated or supinated, is most frequently associated with plantar fasciitis. The 100 study participants (34 men and 66 women) were divided into two groups: patients with plantar fasciitis and controls. The Foot Posture Index and dorsiflexion of the first metatarsophalangeal joint were compared between the two groups, and a correlation analysis was conducted to study their relationship. In the plantar fasciitis group there was a slight limitation of dorsiflexion of the hallux that was not present in the control group (P < .001). Hallux dorsiflexion and the Foot Posture Index were inversely correlated (Spearman correlation coefficient, -0.441; P < .01). Participants with plantar fasciitis presented less hallux dorsiflexion than those in the control group, and their most common foot type was the pronated foot.

  1. Ultrasound-assisted endoscopic partial plantar fascia release.

    PubMed

    Ohuchi, Hiroshi; Ichikawa, Ken; Shinga, Kotaro; Hattori, Soichi; Yamada, Shin; Takahashi, Kazuhisa

    2013-01-01

    Various surgical treatment procedures for plantar fasciitis, such as open surgery, percutaneous release, and endoscopic surgery, exist. Skin trouble, nerve disturbance, infection, and persistent pain associated with prolonged recovery time are complications of open surgery. Endoscopic partial plantar fascia release offers the surgeon clear visualization of the anatomy at the surgical site. However, the primary medial portal and portal tract used for this technique have been shown to be in close proximity to the posterior tibial nerves and their branches, and there is always the risk of nerve damage by introducing the endoscope deep to the plantar fascia. By performing endoscopic partial plantar fascia release under ultrasound assistance, we could dynamically visualize the direction of the endoscope and instrument introduction, thus preventing nerve damage from inadvertent insertion deep to the fascia. Full-thickness release of the plantar fascia at the ideal position could also be confirmed under ultrasound imaging. We discuss the technique for this new procedure.

  2. Ultrasound-Assisted Endoscopic Partial Plantar Fascia Release

    PubMed Central

    Ohuchi, Hiroshi; Ichikawa, Ken; Shinga, Kotaro; Hattori, Soichi; Yamada, Shin; Takahashi, Kazuhisa

    2013-01-01

    Various surgical treatment procedures for plantar fasciitis, such as open surgery, percutaneous release, and endoscopic surgery, exist. Skin trouble, nerve disturbance, infection, and persistent pain associated with prolonged recovery time are complications of open surgery. Endoscopic partial plantar fascia release offers the surgeon clear visualization of the anatomy at the surgical site. However, the primary medial portal and portal tract used for this technique have been shown to be in close proximity to the posterior tibial nerves and their branches, and there is always the risk of nerve damage by introducing the endoscope deep to the plantar fascia. By performing endoscopic partial plantar fascia release under ultrasound assistance, we could dynamically visualize the direction of the endoscope and instrument introduction, thus preventing nerve damage from inadvertent insertion deep to the fascia. Full-thickness release of the plantar fascia at the ideal position could also be confirmed under ultrasound imaging. We discuss the technique for this new procedure. PMID:24265989

  3. Brief followup report: Does high-flexion total knee arthroplasty allow deep flexion safely in Asian patients?

    PubMed

    Han, Hyuk-Soo; Kang, Seung-Baik

    2013-05-01

    The long-term survivorship of TKA in Asian countries is comparable to that in Western countries. High-flexion TKA designs were introduced to improve flexion after TKA. However, several studies suggest high-flexion designs are at greater risk of femoral component loosening compared with conventional TKA designs. We previously reported a revision rate of 21% at 11 to 45 months; this report is intended as a followup to that study. Do implant survival and function decrease with time and do high-flexion activities increase the risk of premature failure? We prospectively followed 72 Nexgen LPS-flex fixed TKAs in 47 patients implanted by a single surgeon between March 2003 and September 2004. We determined the probability of survival using revision as an end point and compared survival between those who could and those who could not perform high-flexion activities. Minimum followup was 0.9 years (median, 6.5 years; range, 0.9-8.6 years). Twenty-five patients (33 knees) underwent revision for aseptic loosening of the femoral component at a mean of 4 years (range, 1-8 years). The probability of revision-free survival for aseptic loosening was 67% and 52% at 5 and 8 years, respectively. Eight-year cumulative survivorship was lower in patients capable of squatting, kneeling, or sitting crosslegged (31% compared with 78%). There were no differences in the pre- and postoperative mean Hospital for Special Surgery scores and maximum knee flexion degrees whether or not high-flexion activities could be achieved. Overall midterm high-flexion TKA survival in our Asian cohort was lower than that of conventional and other high-flexion designs. This unusually high rate of femoral component loosening was associated with postoperative high-flexion activities.

  4. Joint torques in a freely walking insect reveal distinct functions of leg joints in propulsion and posture control

    PubMed Central

    2016-01-01

    Determining the mechanical output of limb joints is critical for understanding the control of complex motor behaviours such as walking. In the case of insect walking, the neural infrastructure for single-joint control is well described. However, a detailed description of the motor output in form of time-varying joint torques is lacking. Here, we determine joint torques in the stick insect to identify leg joint function in the control of body height and propulsion. Torques were determined by measuring whole-body kinematics and ground reaction forces in freely walking animals. We demonstrate that despite strong differences in morphology and posture, stick insects show a functional division of joints similar to other insect model systems. Propulsion was generated by strong depression torques about the coxa–trochanter joint, not by retraction or flexion/extension torques. Torques about the respective thorax–coxa and femur–tibia joints were often directed opposite to fore–aft forces and joint movements. This suggests a posture-dependent mechanism that counteracts collapse of the leg under body load and directs the resultant force vector such that strong depression torques can control both body height and propulsion. Our findings parallel propulsive mechanisms described in other walking, jumping and flying insects, and challenge current control models of insect walking. PMID:26791608

  5. Iontophoresis for palmar and plantar hyperhidrosis.

    PubMed

    Pariser, David M; Ballard, Angela

    2014-10-01

    Iontophoresis is a safe, efficacious, and cost-effective primary treatment of palmar and plantar hyperhidrosis. Decades of clinical experience and research show significant reduction in palmoplantar excessive sweating with minimal side effects. To get the best results from iontophoresis, health care professionals need to provide education on the mechanism of action and benefits, evidence of its use, and creation of a future patient-specific plan of care for continued treatments at home or in the physician's office. Iontophoresis may be combined with other hyperhidrosis treatments, such as topical antiperspirants and botulinum toxin injections. Copyright © 2014 Elsevier Inc. All rights reserved.

  6. Plantar pressure cartography reconstruction from 3 sensors.

    PubMed

    Abou Ghaida, Hussein; Mottet, Serge; Goujon, Jean-Marc

    2014-01-01

    Foot problem diagnosis is often made by using pressure mapping systems, unfortunately located and used in the laboratories. In the context of e-health and telemedicine for home monitoring of patients having foot problems, our focus is to present an acceptable system for daily use. We developed an ambulatory instrumented insole using 3 pressures sensors to visualize plantar pressure cartographies. We show that a standard insole with fixed sensor position could be used for different foot sizes. The results show an average error measured at each pixel of 0.01 daN, with a standard deviation of 0.005 daN.

  7. Spin Transfer torques in Antiferromagnets

    NASA Astrophysics Data System (ADS)

    Saidaoui, Hamed; Waintal, Xavier; Manchon, Aurelien; Spsms, Cea, Grenoble France Collaboration

    2013-03-01

    Spin Transfer Torque (STT) has attracted tremendously growing interest in the past two decades. Consisting on the transfer of spin angular momentum of a spin polarized current to local magnetic moments, the STT gives rise to a complex dynamics of the magnetization. Depending on the the structure, the STT shows a dominated In plane component for spin valves, whereas both components coexist for magnetic tunneling junctions (MTJ). For latter case the symmetry of the structure is considered to be decisive in identifying the nature and behavior of the torque. In the present study we are interested in magnetic structures where we substitute either one or both of the magnetic layers by antiferromagnets (AF). We use Non-equilibrium Green's function formalism applied on a tight-binding model to investigate the nature of the spin torque. We notice the presence of two types of torque exerted on (AF), a torque which tends to rotate the order parameter and another one that competes with the exchange interaction. We conclude by comparison with previous works.

  8. Split torque transmission load sharing

    NASA Technical Reports Server (NTRS)

    Krantz, T. L.; Rashidi, M.; Kish, J. G.

    1992-01-01

    Split torque transmissions are attractive alternatives to conventional planetary designs for helicopter transmissions. The split torque designs can offer lighter weight and fewer parts but have not been used extensively for lack of experience, especially with obtaining proper load sharing. Two split torque designs that use different load sharing methods have been studied. Precise indexing and alignment of the geartrain to produce acceptable load sharing has been demonstrated. An elastomeric torque splitter that has large torsional compliance and damping produces even better load sharing while reducing dynamic transmission error and noise. However, the elastomeric torque splitter as now configured is not capable over the full range of operating conditions of a fielded system. A thrust balancing load sharing device was evaluated. Friction forces that oppose the motion of the balance mechanism are significant. A static analysis suggests increasing the helix angle of the input pinion of the thrust balancing design. Also, dynamic analysis of this design predicts good load sharing and significant torsional response to accumulative pitch errors of the gears.

  9. Hyperemia in plantar fasciitis determined by power Doppler ultrasound.

    PubMed

    McMillan, Andrew M; Landorf, Karl B; Gregg, Julie M; De Luca, Jason; Cotchett, Matthew P; Menz, Hylton B

    2013-12-01

    Cross-sectional observational study. To investigate the presence of soft tissue hyperemia in plantar fasciitis with power Doppler ultrasound. Localized hyperemia is an established feature of tendinopathy, suggesting that neurovascular in-growth may contribute to tendon-associated pain in some patients. The presence of abnormal soft tissue vascularity can be assessed with Doppler ultrasound, and a positive finding can assist with targeted treatment plans. However, very little is known regarding the presence of hyperemia in plantar fasciitis and the ability of routine Doppler ultrasound to identify vascular in-growth in the plantar fascia near its proximal insertion. This observational study included 30 participants with plantar fasciitis unrelated to systemic disease and 30 age- and sex-matched controls. Ultrasound examination was performed with a 13- to 5-MHz linear transducer, and power Doppler images were assessed by 2 blinded investigators. Hyperemia of the plantar fascia was present in 8 of 30 participants with plantar fasciitis and in 2 of 30 controls. The between-group difference for hyperemia, using a 4-point scale, was statistically significant, with participants with plantar fasciitis showing increased Doppler ultrasound signal compared to controls (Mann-Whitney U, P = .03). However, the majority of participants with plantar fasciitis with evidence of hyperemia demonstrated very mild color changes, and only 3 were found to have moderate or marked hyperemia. Mild hyperemia can occur with plantar fasciitis, but most individuals will not exhibit greater soft tissue vascularity when assessed with routine Doppler ultrasound. Clinicians treating plantar fasciitis should not consider a positive Doppler signal as essential for diagnosis of the condition but, rather, as a feature that may help to refine the treatment plan for an individual patient.

  10. Diffusion of torqued active particles

    NASA Astrophysics Data System (ADS)

    Sandoval, Mario; Lauga, Eric

    2012-11-01

    Motivated by swimming microorganisms whose trajectories are affected by the presence of an external torque, we calculate the diffusivity of an active particle subject to an external torque and in a fluctuating environment. The analytical results are compared with Brownian dynamics simulations showing excellent agreement between theory and numerical experiments. This work was funded in part by the Consejo Nacional de Ciencia y Tecnologia of Mexico (Conacyt postdoctoral fellowship to M. S.) and the US National Science Foundation (Grant CBET-0746285 to E.L.).

  11. Effect of axial tibial torque direction on ACL relative strain and strain rate in an in vitro simulated pivot landing.

    PubMed

    Oh, Youkeun K; Kreinbrink, Jennifer L; Wojtys, Edward M; Ashton-Miller, James A

    2012-04-01

    Anterior cruciate ligament (ACL) injuries most frequently occur under the large loads associated with a unipedal jump landing involving a cutting or pivoting maneuver. We tested the hypotheses that internal tibial torque would increase the anteromedial (AM) bundle ACL relative strain and strain rate more than would the corresponding external tibial torque under the large impulsive loads associated with such landing maneuvers. Twelve cadaveric female knees [mean (SD) age: 65.0 (10.5) years] were tested. Pretensioned quadriceps, hamstring, and gastrocnemius muscle-tendon unit forces maintained an initial knee flexion angle of 15°. A compound impulsive test load (compression, flexion moment, and internal or external tibial torque) was applied to the distal tibia while recording the 3D knee loads and tibofemoral kinematics. AM-ACL relative strain was measured using a 3 mm DVRT. In this repeated measures experiment, the Wilcoxon signed-rank test was used to test the null hypotheses with p < 0.05 considered significant. The mean (±SD) peak AM-ACL relative strains were 5.4 ± 3.7% and 3.1 ± 2.8% under internal and external tibial torque, respectively. The corresponding mean (± SD) peak AM-ACL strain rates reached 254.4 ± 160.1%/s and 179.4 ± 109.9%/s, respectively. The hypotheses were supported in that the normalized mean peak AM-ACL relative strain and strain rate were 70 and 42% greater under internal than under external tibial torque, respectively (p = 0.023, p = 0.041). We conclude that internal tibial torque is a potent stressor of the ACL because it induces a considerably (70%) larger peak strain in the AM-ACL than does a corresponding external tibial torque. Copyright © 2011 Orthopaedic Research Society.

  12. EFFECT OF AXIAL TIBIAL TORQUE DIRECTION ON ACL RELATIVE STRAIN AND STRAIN RATE IN AN IN VITRO SIMULATED PIVOT LANDING

    PubMed Central

    Oh, Youkeun K.; Kreinbrink, Jennifer L.; Wojtys, Edward M.; Ashton-Miller, James A.

    2011-01-01

    Anterior cruciate ligament (ACL) injuries most frequently occur under the large loads associated with a unipedal jump landing involving a cutting or pivoting maneuver. We tested the hypotheses that internal tibial torque would increase the anteromedial (AM) bundle ACL relative strain and strain rate more than would the corresponding external tibial torque under the large impulsive loads associated with such landing maneuvers. Twelve cadaveric female knees [mean (SD) age: 65.0 (10.5) years] were tested. Pretensioned quadriceps, hamstring and gastrocnemius muscle-tendon unit forces maintained an initial knee flexion angle of 15°. A compound impulsive test load (compression, flexion moment and internal or external tibial torque) was applied to the distal tibia while recording the 3-D knee loads and tibofemoral kinematics. AM-ACL relative strain was measured using a 3mm DVRT. In this repeated measures experiment, the Wilcoxon Signed-Rank test was used to test the null hypotheses with p<0.05 considered significant. The mean (± SD) peak AM-ACL relative strains were 5.4±3.7 % and 3.1±2.8 % under internal and external tibial torque, respectively. The corresponding mean (± SD) peak AM-ACL strain rates reached 254.4±160.1 %/sec and 179.4±109.9 %/sec, respectively. The hypotheses were supported in that the normalized mean peak AM-ACL relative strain and strain rate were 70% and 42% greater under internal than external tibial torque, respectively (p=0.023, p=0.041). We conclude that internal tibial torque is a potent stressor of the ACL because it induces a considerably (70%) larger peak strain in the AM-ACL than does a corresponding external tibial torque. PMID:22025178

  13. [Plantar fibromatosis and Dupuytren's contracture in an adolescent].

    PubMed

    Nikolić, Jelena; Janjić, Zlata; Momcilović, Dragan; Ninković, Srdjan; Harhai, Vladimir

    2011-10-01

    Fibromatosis represents a wide group of benign, locally proliferative disorders of fibroblasts. Dupuytren's disease is a benign proliferative disease of palmar aponeurosis which usually affects adults between 40 and 60 years of age. Ledderhose's disease or plantar fibromatosis is plantar equivalent of Dupuyten's disease most often affecting middle-aged and older men, usually bilateral, represented with painless nodule in the medial division of plantar fascia. We presented a 19-year old adolescent that turned to a plastic surgeon complaining to his small finger contracture. He noticed palmar thickening with nodule over the metacarpophalangeal joint of small finger of his right hand when he was 16 years old. A year later a finger started to band. During physical checkup we noticed plantar nodule that also had his father and grandmother. Magnetic resonance and tumor biopsy confirmed a suspicion on plantar fibromatosis - Ledderhose's disease. Clinical exam of the hand clearly led to a conclusion that the patient had Dupuytren's contracture with pretendinous cord over the small finger flexor tendons and lack of extension of proximal interphalangeal (PIP) joint. On the extensor side of the PIP joints there were Garrod's nodes. The patient refused surgical treatment of plantar tumor, but agreed to surgical correction of finger contracture. Despite the fact that Dupuytren's disease and plantar fibromatosis are diseases of adults, the possibility of conjoint appearance of these forms of fibromatosis in adolescent period of life should be kept in mind especially in patients with strong genetic predisposition.

  14. Can foot anthropometric measurements predict dynamic plantar surface contact area?

    PubMed

    McPoil, Thomas G; Vicenzino, Bill; Cornwall, Mark W; Collins, Natalie

    2009-10-28

    Previous studies have suggested that increased plantar surface area, associated with pes planus, is a risk factor for the development of lower extremity overuse injuries. The intent of this study was to determine if a single or combination of foot anthropometric measures could be used to predict plantar surface area. Six foot measurements were collected on 155 subjects (97 females, 58 males, mean age 24.5 +/- 3.5 years). The measurements as well as one ratio were entered into a stepwise regression analysis to determine the optimal set of measurements associated with total plantar contact area either including or excluding the toe region. The predicted values were used to calculate plantar surface area and were compared to the actual values obtained dynamically using a pressure sensor platform. A three variable model was found to describe the relationship between the foot measures/ratio and total plantar contact area (R2 = 0.77, p < 0.0001)). A three variable model was also found to describe the relationship between the foot measures/ratio and plantar contact area minus the toe region (R2 = 0.76, p < 0.0001). The results of this study indicate that the clinician can use a combination of simple, reliable, and time efficient foot anthropometric measurements to explain over 75% of the plantar surface contact area, either including or excluding the toe region.

  15. Can foot anthropometric measurements predict dynamic plantar surface contact area?

    PubMed Central

    2009-01-01

    Background Previous studies have suggested that increased plantar surface area, associated with pes planus, is a risk factor for the development of lower extremity overuse injuries. The intent of this study was to determine if a single or combination of foot anthropometric measures could be used to predict plantar surface area. Methods Six foot measurements were collected on 155 subjects (97 females, 58 males, mean age 24.5 ± 3.5 years). The measurements as well as one ratio were entered into a stepwise regression analysis to determine the optimal set of measurements associated with total plantar contact area either including or excluding the toe region. The predicted values were used to calculate plantar surface area and were compared to the actual values obtained dynamically using a pressure sensor platform. Results A three variable model was found to describe the relationship between the foot measures/ratio and total plantar contact area (R2 = 0.77, p < 0.0001)). A three variable model was also found to describe the relationship between the foot measures/ratio and plantar contact area minus the toe region (R2 = 0.76, p < 0.0001). Conclusion The results of this study indicate that the clinician can use a combination of simple, reliable, and time efficient foot anthropometric measurements to explain over 75% of the plantar surface contact area, either including or excluding the toe region. PMID:19863799

  16. Association Between Plantar Fasciitis and Isolated Gastrocnemius Tightness.

    PubMed

    Nakale, Ngenomeulu T; Strydom, Andrew; Saragas, Nick P; Ferrao, Paulo N F

    2018-03-01

    An association between plantar fasciitis and isolated gastrocnemius tightness (IGT) has been postulated in the literature; however, there have been few studies to prove this relationship. This prospective cross-sectional cohort study was aimed at determining the association between plantar fasciitis and IGT. Three groups comprising 45 patients with plantar fasciitis (group 1), 117 patients with foot and ankle pathology other than plantar fasciitis (group 2), and 61 patients without foot and ankle pathology (group 3) were examined for the presence of IGT using the Silfverskiöld test. Statistical tests included chi-square test, Student t test, and analysis of variance. Of the patients, 101 (45.3%) had IGT: 36 (80%) in group 1, 53 (45.3%) in group 2, and 12 (19.7%) in group 3. The difference in IGT prevalence between the groups was statistically significant at P < .001. The prevalence of IGT was similar between acute and chronic plantar fasciitis at 78.9% and 80.6%, respectively. There was a very strong association between plantar fasciitis and IGT using group 3 as a reference. This study suggests that IGT should be actively sought out and managed in patients with plantar fasciitis. Level II, cross-sectional cohort prospective study.

  17. Ultrasound evaluation of a spontaneous plantar fascia rupture.

    PubMed

    Louwers, Michael J; Sabb, Brian; Pangilinan, Percival H

    2010-11-01

    Plantar fascia rupture is an occasional complication in patients with chronic plantar fasciitis or in patients with plantar fasciitis treated with steroid injection. Very few cases of spontaneous plantar fascia rupture have been reported in the literature (Herrick and Herrick, Am J Sports Med 1983;11:95; Lun et al, Clin J Sports Med 1999;9:48-9; Rolf et al, J Foot Ankle Surg 1997;36:112-4; Saxena and Fullem, Am J Sports Med 2004;32:662-5). Spontaneous medial plantar fascia rupture in a 37-yr-old man with no preceding symptoms or steroid injections was confirmed with diagnostic ultrasound, which revealed severe fasciitis at the calcaneal insertion with partial tearing. After conservative treatment, the patient returned to full activities. We discuss the anatomy, risk factors, examination findings, and treatment for this condition, as well as the unique benefits that ultrasound offers over magnetic resonance imaging. It is important to consider plantar fascia rupture in patients with hindfoot pain and medioplantar ecchymosis, particularly if an injury occurred during acceleration maneuvers. Ultrasound in these cases can be used to diagnose a plantar fascia tear quickly, accurately, and cost-effectively.

  18. Subcalcaneal Bursitis With Plantar Fasciitis Treated by Arthroscopy

    PubMed Central

    Yamakado, Kotaro

    2013-01-01

    We report the successful arthroscopic treatment of a case of subcalcaneal bursitis with plantar fasciitis. To our knowledge, this is the first report on arthroscopic excision of a subcalcaneal bursa. Right heel pain developed in a 50-year-old woman, without any obvious cause. She reported that the heel pain occurred immediately after waking and that the heel ached when she walked. Magnetic resonance imaging showed an extra-articular, homogeneous, high-intensity lesion in the fat pad adjacent to the calcaneal tubercle on T2-weighted sagittal and coronal images and thickening of the plantar fascia on T2-weighted sagittal images. A diagnosis of a recalcitrant subcalcaneal bursitis with plantar fasciitis was made, and surgery was performed. The arthroscope was placed between the calcaneus and the plantar fascia. With the surgeon viewing from the lateral portal and working from the medial portal, the dorsal surface of the degenerative plantar fascia was debrided and the medial half of the plantar fascia was released, followed by debridement of the subcalcaneal bursal cavity through the incised plantar fascia. Full weight bearing and gait were allowed immediately after the operation. At the latest follow-up, the patient had achieved complete resolution of heel pain without a recurrence of the mass, confirmed by magnetic resonance imaging. PMID:23875139

  19. Determinants of footwear difficulties in people with plantar heel pain.

    PubMed

    Sullivan, Justin; Pappas, Evangelos; Adams, Roger; Crosbie, Jack; Burns, Joshua

    2015-01-01

    Plantar heel pain is a common foot disorder aggravated by weight-bearing activity. Despite considerable focus on therapeutic interventions such as orthoses, there has been limited investigation of footwear-related issues in people with plantar heel pain. The aim of this study was to investigate whether people with plantar heel pain experience footwear-related difficulties compared to asymptomatic individuals, as well as identifying factors associated with footwear comfort, fit and choice. The footwear domain of the Foot Health Status Questionnaire (FHSQ) was assessed in 192 people with plantar heel pain and 69 asymptomatic controls. The plantar heel pain group was also assessed on a variety of measures including: foot posture, foot strength and flexibility, pedobarography and pain level. A univariate analysis of covariance, with age as the covariate, was used to compare the heel pain and control groups on the FHSQ footwear domain score. A multiple regression model was then constructed to investigate factors associated with footwear scores among participants with plantar heel pain. When compared to asymptomatic participants, people with plantar heel pain reported lower FHSQ footwear domain scores (mean difference -24.4; p < 0.001; 95 % CI: -32.0 to -17.0). In the participants with heel pain, footwear scores were associated with maximum force beneath the postero-lateral heel during barefoot walking, toe flexor strength and gender. People with plantar heel pain experience difficulty with footwear comfort, fit and choice. Reduced heel loading during barefoot walking, toe flexor weakness and female gender are all independently associated with reports of footwear difficulties in people with heel pain. Increased focus, in both clinical and research settings, is needed to address footwear-related issues in people with plantar heel pain.

  20. Classification of Calcaneal Spurs and Their Relationship With Plantar Fasciitis.

    PubMed

    Zhou, Binghua; Zhou, You; Tao, Xu; Yuan, Chengsong; Tang, Kanglai

    2015-01-01

    Calcaneal spurs, as a cause of plantar fasciitis, are currently debatable. A prospective study was performed to classify calcaneal spurs according to the findings from an investigation of the relationship between calcaneal spurs and plantar fasciitis. Thirty patients with calcaneal spurs and plantar heel pain underwent calcaneal spur removal and endoscopic plantar fasciotomy. The relationship between the classification of calcaneal spurs and plantar fasciitis was evaluated by endoscopic findings, clinical symptoms, radiographic images, and biopsy findings. The visual analog scale for pain and the American Orthopedic Foot and Ankle Society ankle-hindfoot scores for functional evaluation were used preoperatively and postoperatively, respectively. The mean follow-up period was 24 months. Two separate types of calcaneal spurs were recognized. Type A calcaneal spurs were located superior to the plantar fascia insertion, and type B calcaneal spurs were located within the plantar fascia. Magnetic resonance imaging results showed a more severe plantar fasciitis grade in type B calcaneal spurs preoperatively. Histologic examination showed that the numbers of granulocytes per image in type B spurs were significantly increased compared with those in type A spurs. Statistically significant improvements were found in the mean visual analog scale and American Orthopedic Foot and Ankle Society scores and magnetic resonance imaging results in both groups. The amount of change in the visual analog scale score and American Orthopedic Foot and Ankle Society score, the number of granulocytes per image, and calcaneal spur length showed a high association with the classification of the calcaneal spurs. Calcaneal spurs were completely removed and did not recur in any of the patients on radiographic assessment during the follow-up period. Calcaneal spurs can be classified into 2 distinct types that are indicative of the severity of plantar fasciitis. Copyright © 2015 American College of

  1. Installation Torque Tables for Noncritical Applications

    NASA Technical Reports Server (NTRS)

    Rivera-Rosario, Hazel T.; Powell, Joseph S.

    2017-01-01

    The objective of this project is to define torque values for bolts and screws when loading is not a concern. Fasteners require a certain torque to fulfill its function and prevent failure. NASA Glenn Research Center did not have a set of fastener torque tables for non-critical applications without loads, usually referring to hand-tight or wrench-tight torqueing. The project is based on two formulas, torque and pullout load. Torque values are calculated giving way to preliminary data tables. Testing is done to various bolts and metal plates, torqueing them until the point of failure. Around 640 torque tables were developed for UNC, UNF, and M fasteners. Different lengths of thread engagement were analyzed for the 5 most common materials used at GRC. The tables were put together in an Excel spreadsheet and then formatted into a Word document. The plan is to later convert this to an official technical publication or memorandum.

  2. Preload Torque Limiting Shaft Coupling

    NASA Technical Reports Server (NTRS)

    Harmening, W. A. (Inventor)

    1975-01-01

    A torque limiting spring for a rotating shaft system which acts bidirectionally and is preloaded is examined. The spring is a split circular ring compressed into cavities on facing surfaces of matching shafts. The spring is preloaded by varying the width of a tang in the shaft cavity relative to the split in the spring.

  3. Hereditary determinants of manual torque.

    PubMed

    Matheny, A P

    1979-12-01

    Data from a longitudinal study of twin children and siblings, 155 girls and 134 boys (aged 4 to 9 yr.), on a torque test confirmed that during this age period manually produced circling patterns change from clockwise to counterclockwise orientation. A genetic influence is suggested.

  4. Aerodynamics of dynamic wing flexion in translating wings

    NASA Astrophysics Data System (ADS)

    Liu, Yun; Cheng, Bo; Sane, Sanjay P.; Deng, Xinyan

    2015-06-01

    We conducted a systematic experimental study to investigate the aerodynamic effects of active trailing-edge flexion on a high-aspect-ratio wing translating from rest at a high angle of attack. We varied the timing and speed of the trailing-edge flexion and measured the resulting aerodynamic effects using a combination of direct force measurements and two-dimensional PIV flow measurements. The results indicated that the force and flow characteristics depend strongly on the timing of flexion, but relatively weakly on its speed. This is because the force and vortical flow structure are more sensitive to the timing of flexion relative to the shedding of starting vortex and leading-edge vortex. When the trailing-edge flexion occurred slightly before the starting vortex was shed, the lift production was greatly improved with the instantaneous peak lift increased by 54 % and averaged lift increased by 21 % compared with the pre-flexed case where the trailing-edge flexed before wing translation. However, when the trailing-edge flexed during or slightly after the leading-edge vortex shedding, the lift was significantly reduced by the disturbed development of leading-edge vortex. The force measurement results also imply that the trailing-edge flexion prior to wing translation does not augment lift but increases drag, thus resulting in a lower lift-drag ratio as compared to the case of flat wing.

  5. The effect of the gastrocnemius on the plantar fascia.

    PubMed

    Pascual Huerta, Javier

    2014-12-01

    Although anatomic and functional relationship has been established between the gastrocnemius muscle, via the Achilles tendon, and the plantar fascia, the exact role of gastrocnemius tightness in foot and plantar fascia problems is not completely understood. This article summarizes past and current literature linking these 2 structures and gives a mechanical explanation based on functional models of the relationship between gastrocnemius tightness and plantar fascia. The effect of gastrocnemius tightness on the sagittal behavior of the foot is also discussed. Copyright © 2014 Elsevier Inc. All rights reserved.

  6. Endoscopic plantar fascia release via a suprafascial approach is effective for intractable plantar fasciitis.

    PubMed

    Miyamoto, Wataru; Yasui, Youichi; Miki, Shinya; Kawano, Hirotaka; Takao, Masato

    2017-10-14

    To evaluate the medium-term clinical results of endoscopic plantar fascia release (EPFR) using a suprafascial approach for recalcitrant plantar fasciitis. Twenty-four feet of twenty-three patients who underwent EPFR using a suprafascial approach were followed up for more than 2 years using the American Orthopedic Foot and Ankle Society (AOFAS) score. The AOFAS score at final follow-up was compared between patients who participated in athletic activity (group A) and those who were sedentary (group S) and between those with and those without calcaneal spur (group with CS and group without CS, respectively). The ability of patients to return to athletic activity, and if so, the time interval between surgery and return to athletic activity, were investigated in group A. Complications were recorded. The median follow-up duration was 48 months. The mean AOFAS score in all patients increased significantly between before surgery and final follow-up (P < 0.001). The mean score in group A at final follow-up was significantly higher than that in group S (P < 0.05). However, there was no significant difference in the mean score at final follow-up between the groups with and without CS. In group A, all patients could return to athletic activity after a median 8 weeks. Injury to the first branch of the lateral plantar nerve occurred in three feet. EPFR using a suprafascial approach was effective for recalcitrant plantar fasciitis. However, the prognosis of sedentary patients was inferior to that of patients engaged in athletic activity. IV.

  7. Postactivation Potentiation of the Plantar Flexors Does Not Directly Translate to Jump Performance in Female Elite Young Soccer Players.

    PubMed

    Prieske, Olaf; Maffiuletti, Nicola A; Granacher, Urs

    2018-01-01

    High-intensity muscle actions have the potential to temporarily improve muscle contractile properties (i.e., postactivation potentiation, PAP) thereby inducing acute performance enhancements. There is evidence that balance training can improve performance during strength exercises. Taking these findings together, the purpose of this study was to examine the acute effects of a combined balance and strength (B+S) exercise vs. a strength only (S) exercise on twitch contractile properties, maximum voluntary strength, and jump performance in young athletes. Female elite young soccer players ( N = 12) aged 14-15 years conducted three experimental conditions in randomized order: S included 3 sets of 8-10 dynamic leg extensions at 80% of the 1-repetition maximum, B+S consisted of 3 sets of 40 s double-leg stances on a balance board prior to leg extensions (same as S), and a resting control period. Before and 7 min after exercise, participants were tested for their electrically-evoked isometric twitches (i.e., twitch peak torque, twitch rate of torque development) and maximal voluntary contraction (MVC) torque of the plantar flexor muscles. Additionally, countermovement (CMJ) and drop jump (DJ) performances (i.e., CMJ/DJ height, DJ ground contact time) were assessed. Significant effects of condition on twitch contractile properties ( p < 0.05, d = 1.1) and jump performance outputs ( p < 0.05, 1.1 ≤ d ≤ 1.2) were found. Post-hoc tests revealed that S compared to control produced larger PAP for twitch peak torques by trend ( p = 0.07, d = 1.8, 33 vs. 21%) and significantly larger PAP for twitch rate of torque development ( p < 0.05, d = 2.4, 55 vs. 43%). Following B+S compared to control, significant improvements in CMJ height ( p < 0.01, d = 1.9, 3%) and DJ contact time were found ( p < 0.01, d = 2.0, 10%). This study revealed protocol-specific acute performance improvements. While S resulted in significant increases in twitch contractile properties, B+S produced

  8. Postactivation Potentiation of the Plantar Flexors Does Not Directly Translate to Jump Performance in Female Elite Young Soccer Players

    PubMed Central

    Prieske, Olaf; Maffiuletti, Nicola A.; Granacher, Urs

    2018-01-01

    High-intensity muscle actions have the potential to temporarily improve muscle contractile properties (i.e., postactivation potentiation, PAP) thereby inducing acute performance enhancements. There is evidence that balance training can improve performance during strength exercises. Taking these findings together, the purpose of this study was to examine the acute effects of a combined balance and strength (B+S) exercise vs. a strength only (S) exercise on twitch contractile properties, maximum voluntary strength, and jump performance in young athletes. Female elite young soccer players (N = 12) aged 14–15 years conducted three experimental conditions in randomized order: S included 3 sets of 8–10 dynamic leg extensions at 80% of the 1-repetition maximum, B+S consisted of 3 sets of 40 s double-leg stances on a balance board prior to leg extensions (same as S), and a resting control period. Before and 7 min after exercise, participants were tested for their electrically-evoked isometric twitches (i.e., twitch peak torque, twitch rate of torque development) and maximal voluntary contraction (MVC) torque of the plantar flexor muscles. Additionally, countermovement (CMJ) and drop jump (DJ) performances (i.e., CMJ/DJ height, DJ ground contact time) were assessed. Significant effects of condition on twitch contractile properties (p < 0.05, d = 1.1) and jump performance outputs (p < 0.05, 1.1 ≤ d ≤ 1.2) were found. Post-hoc tests revealed that S compared to control produced larger PAP for twitch peak torques by trend (p = 0.07, d = 1.8, 33 vs. 21%) and significantly larger PAP for twitch rate of torque development (p < 0.05, d = 2.4, 55 vs. 43%). Following B+S compared to control, significant improvements in CMJ height (p < 0.01, d = 1.9, 3%) and DJ contact time were found (p < 0.01, d = 2.0, 10%). This study revealed protocol-specific acute performance improvements. While S resulted in significant increases in twitch contractile properties, B+S produced

  9. Radiofrequency microtenotomy is as effective as plantar fasciotomy in the treatment of recalcitrant plantar fasciitis.

    PubMed

    Chou, Andrew Chia Chen; Ng, Sean Yung Chuan; Su, David Hsien Ching; Singh, Inderjeet Rikhraj; Koo, Kevin

    2016-12-01

    Radiofrequency microtenotomy (RM) is effective for treating plantar fasciitis. No studies have compared it to the plantar fasciotomy (PF). We hypothesized that RM is equally effective and provides no additional benefit when performed with PF. Between 2007 and 2014, all patients who underwent either or both procedures concurrently at our institution were analyzed. Data collected included demographics, SF-36 Health Survey, AOFAS Ankle-Hindfoot Scale, and two questions regarding satisfaction and expectations, all of which were assessed pre-operatively and post-operatively at 6-months and 1-year. ANOVA with Bonferroni correction was used to compare scores at each interval. Logistic regression was used to identify pre-operative factors that predicted for satisfaction and expectations. There were no differences in patient outcomes. No pre-operative factors predicted for satisfaction and expectations. RM is as effective as PF in the treatment of plantar fasciitis. Patients who underwent both procedures experienced no benefit and a higher rate of complications. Copyright © 2015 European Foot and Ankle Society. Published by Elsevier Ltd. All rights reserved.

  10. Computerized Torque Control for Large dc Motors

    NASA Technical Reports Server (NTRS)

    Willett, Richard M.; Carroll, Michael J.; Geiger, Ronald V.

    1987-01-01

    Speed and torque ranges in generator mode extended. System of shunt resistors, electronic switches, and pulse-width modulation controls torque exerted by large, three-phase, electronically commutated dc motor. Particularly useful for motor operating in generator mode because it extends operating range to low torque and high speed.

  11. 14 CFR 29.361 - Engine torque.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 14 Aeronautics and Space 1 2012-01-01 2012-01-01 false Engine torque. 29.361 Section 29.361... STANDARDS: TRANSPORT CATEGORY ROTORCRAFT Strength Requirements Flight Loads § 29.361 Engine torque. The limit engine torque may not be less than the following: (a) For turbine engines, the highest of— (1) The...

  12. 14 CFR 29.361 - Engine torque.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 14 Aeronautics and Space 1 2014-01-01 2014-01-01 false Engine torque. 29.361 Section 29.361... STANDARDS: TRANSPORT CATEGORY ROTORCRAFT Strength Requirements Flight Loads § 29.361 Engine torque. The limit engine torque may not be less than the following: (a) For turbine engines, the highest of— (1) The...

  13. 14 CFR 29.361 - Engine torque.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 14 Aeronautics and Space 1 2011-01-01 2011-01-01 false Engine torque. 29.361 Section 29.361... STANDARDS: TRANSPORT CATEGORY ROTORCRAFT Strength Requirements Flight Loads § 29.361 Engine torque. The limit engine torque may not be less than the following: (a) For turbine engines, the highest of— (1) The...

  14. 14 CFR 29.361 - Engine torque.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 14 Aeronautics and Space 1 2013-01-01 2013-01-01 false Engine torque. 29.361 Section 29.361... STANDARDS: TRANSPORT CATEGORY ROTORCRAFT Strength Requirements Flight Loads § 29.361 Engine torque. The limit engine torque may not be less than the following: (a) For turbine engines, the highest of— (1) The...

  15. 14 CFR 29.361 - Engine torque.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 14 Aeronautics and Space 1 2010-01-01 2010-01-01 false Engine torque. 29.361 Section 29.361... STANDARDS: TRANSPORT CATEGORY ROTORCRAFT Strength Requirements Flight Loads § 29.361 Engine torque. The limit engine torque may not be less than the following: (a) For turbine engines, the highest of— (1) The...

  16. Improved Force-And-Torque Sensor Assembly

    NASA Technical Reports Server (NTRS)

    Bamford, Robert M.

    1991-01-01

    Improved sensor assembly measures forces and torques of interaction between supporting and supported object. Measures all three components of force and all three components of torque. Force measurements uncoupled from torque measurements. Price for improved measurement capability, complexity and flexibility, excessive in some applications.

  17. Influence of different safety shoes on gait and plantar pressure: a standardized examination of workers in the automotive industry

    PubMed Central

    Ochsmann, Elke; Noll, Ulrike; Ellegast, Rolf; Hermanns, Ingo; Kraus, Thomas

    2016-01-01

    Objective: Working conditions, such as walking and standing on hard surfaces, can increase the development of musculoskeletal complaints. At the interface between flooring and musculoskeletal system, safety shoes may play an important role in the well-being of employees. The aim of this study was to evaluate the effects of different safety shoes on gait and plantar pressure distributions on industrial flooring. Methods: Twenty automotive workers were individually fitted out with three different pairs of safety shoes ( "normal" shoes, cushioned shoes, and midfoot bearing shoes). They walked at a given speed of 1.5 m/s. The CUELA measuring system and shoe insoles were used for gait analysis and plantar pressure measurements, respectively. Statistical analysis was conducted by ANOVA analysis for repeated measures. Results: Walking with cushioned safety shoes or a midfoot bearing safety shoe led to a significant decrease of the average trunk inclination (p<0.005). Furthermore, the average hip flexion angle decreased for cushioned shoes as well as midfoot bearing shoes (p<0.002). The range of motion of the knee joint increased for cushioned shoes. As expected, plantar pressure distributions varied significantly between cushioned or midfoot bearing shoes and shoes without ergonomic components. Conclusion: The overall function of safety shoes is the avoidance of injury in case of an industrial accident, but in addition, safety shoes could be a long-term preventive instrument for maintaining health of the employees' musculoskeletal system, as they are able to affect gait parameters. Further research needs to focus on safety shoes in working situations. PMID:27488038

  18. Effect of selected exercises on in-shoe plantar pressures in people with diabetes and peripheral neuropathy

    PubMed Central

    Shah, Kshamata M.; Mueller, Michael J.

    2012-01-01

    BACKGROUND In people with diabetes and peripheral neuropathy (DM+PN), injury risk is not clearly known for weight bearing (WB) vs. non-weight bearing (NWB) exercise. In-shoe peak plantar pressures (PPP) often are used as a surrogate indicator of injury to the insensitive foot. OBJECTIVE Compare PPPs in people with DM+PN during selected WB and NWB exercises. METHODS 15 subjects with DM+PN participated. PPPs were recorded for the forefoot, midfoot, and heel during level walking and compared to; WB exercises - treadmill walking, heel and toe raises, sit to stands, stair climbing, single leg standing; and NWB exercises - stationary bicycling, balance ball exercise and plantar flexion exercise. RESULTS Compared to level walking; mean forefoot PPP during treadmill walking was 13% higher, but this difference was eliminated when walking speed was used as a covariate. Mean PPPs were similar or substantially lower for other exercises, except for higher forefoot PPP with heel raise exercises. CONCLUSIONS Slow progression and regular monitoring of insensitive feet are recommended for all exercises, but especially for heel raises, and increases in walking speed. The remaining WB and NWB exercises pose no greater risk to the insensitive foot due to increases in PPP compared to level walking. PMID:22677098

  19. [Multiple post-chemotherapy plantar nevi].

    PubMed

    Hueso, Luis; Requena, Celia; Serra-Guillén, Carlos; Alfaro, Alberto; Nagore, Eduardo; Llombart, Beatriz; Botella-Estrada, Rafael; Sanmartín, Onofre; Guillén, Carlos

    2006-06-01

    The induction of multiple melanocytic nevi in children after chemotherapy has been documented in the literature. This situation apparently has more to do with the state of immunosuppression that is produced than with any specific agent used. We present the case of a 12-year-old girl who presented with multiple plantar melanocytic nevi after multidrug chemotherapy for acute lymphocytic leukemia. None of the lesions showed any alarming clinical signs. Although the degeneration of post-chemotherapy melanocytic nevi to melanoma has not been documented in any of the cases described, the presence of a high number of melanocytic nevi is an accepted risk factor for melanoma; thus, close clinical follow-up of these patients seems advisable.

  20. Fiber optic plantar pressure/shear sensor

    NASA Astrophysics Data System (ADS)

    Soetanto, William; Nguyen, Ngoc T.; Wang, Wei-Chih

    2011-04-01

    A full-scale foot pressure/shear sensor that has been developed to help diagnose the cause of ulcer formation in diabetic patients is presented. The design involves a tactile sensor array using intersecting optical fibers embedded in soft elastomer. The basic configuration incorporates a mesh that is comprised of two sets of parallel optical fiber plane; the planes are configured so the parallel rows of fiber of the top and bottom planes are perpendicular to each other. Threedimensional information is determined by measuring the loss of light from each of the waveguide to map the overall pressure distribution and the shifting of the layers relative to each other. In this paper we will present the latest development on the fiber optic plantar pressure/shear sensor which can measure normal force up from 19.09 kPa to 1000 kPa.

  1. Mountaineering-induced bilateral plantar paresthesia.

    PubMed

    Henderson, Kyle K; Parker, Justine; Heinking, Kurt P

    2014-07-01

    Flat feet (pes planus) have been implicated in multiple musculoskeletal complaints, which are often exacerbated by lack of appropriate arch support or intense exercise. To investigate the efficacy of osteopathic manipulative treatment (OMT) on a patient (K.K.H.) with mountaineering-induced bilateral plantar paresthesia and to assess the association of pes planus with paresthesia in members of the mountaineering expedition party that accompanied the patient. A patient history and physical examination of the musculoskeletal system were performed. The hindfoot, midfoot, forefoot, big toe, and distal toes were evaluated for neurologic function, specifically pin, vibration, 10-g weight sensitivity, and 2-point discrimination during the 4-month treatment period. To determine if OMT could augment recovery, the patient volunteered to use the contralateral leg as a control, with no OMT performed on the sacrum or lower back. To determine if pes planus was associated with mountaineering-induced paresthesia, a sit-to-stand navicular drop test was performed on members of the expedition party. Osteopathic manipulative treatment improved fibular head motion and muscular flexibility and released fascial restrictions of the soleus, hamstring, popliteus, and gastrocnemius. The patient's perception of stiffness, pain, and overall well-being improved with OMT. However, OMT did not shorten the duration of paresthesia. Of the 9 expedition members, 2 experienced paresthesia. Average navicular drop on standing was 5.1 mm for participants with no paresthesia vs 8.9 mm for participants with paresthesia (t test, P<.01; Mann-Whitney rank sum test, P=.06). These preliminary findings suggest that weakened arches may contribute to mountaineering-induced plantar paresthesia. Early diagnosis of pes planus and treatment with orthotics (which may prevent neuropathies)--or, less ideally, OMT after extreme exercise--should be sought to relieve tension and discomfort. © 2014 The American Osteopathic

  2. Plantar pressures determinants in mild Hallux Valgus.

    PubMed

    Martínez-Nova, Alfonso; Sánchez-Rodríguez, Raquel; Pérez-Soriano, Pedro; Llana-Belloch, Salvador; Leal-Muro, Alejo; Pedrera-Zamorano, Juan Diego

    2010-07-01

    While podobarometric techniques have been applied to the study of pressures in Hallux Valgus (HV), little is known about its clinical and radiological determinants. So, the aim of the present study was to determine the plantar pressure pattern in participants with mild HV, comparing to a control group, and their clinical and anthropometric determinants. Biofoot/IBV(®) in-shoe system was used to evaluate 79 participants with mild HV. Computerized measurements of the 1st intermetatarsal angle (IMA) and the hallux abductus angle (HAA) were made on antero-posterior radiographs. The clinical outcome was assessed using the AOFAS score. The dependent baropodometric variables and the independent clinical and anthropometric variables were subjected to a multiple regression analysis. In both groups, the highest average pressure was in the 2nd metatarsal head (MTH). The mean pressure under the Hallux was significantly higher in HV group (controls, 146.5±92.5kPa; HV, 328.5±113.2kPa; p<0.001). An 18.6% of average pressure under the 1st MTH was accounted for pain, first ray alignment and total AOFAS score. Variations of the HAA explained 26.8% of the mean Hallux pressure. Women with mild HV present with pathologically increased pressure under the Hallux, which is caused by the altered alignment of the first ray. Pain and clinical result were associated with the pressure under the 1st MTH and the remaining variables were only moderate predictors of dynamic plantar pressures. Copyright © 2010 Elsevier B.V. All rights reserved.

  3. Foot Modeling and Smart Plantar Pressure Reconstruction from Three Sensors

    PubMed Central

    Ghaida, Hussein Abou; Mottet, Serge; Goujon, Jean-Marc

    2014-01-01

    In order to monitor pressure under feet, this study presents a biomechanical model of the human foot. The main elements of the foot that induce the plantar pressure distribution are described. Then the link between the forces applied at the ankle and the distribution of the plantar pressure is established. Assumptions are made by defining the concepts of a 3D internal foot shape, which can be extracted from the plantar pressure measurements, and a uniform elastic medium, which describes the soft tissues behaviour. In a second part, we show that just 3 discrete pressure sensors per foot are enough to generate real time plantar pressure cartographies in the standing position or during walking. Finally, the generated cartographies are compared with pressure cartographies issued from the F-SCAN system. The results show 0.01 daN (2% of full scale) average error, in the standing position. PMID:25400713

  4. Foot modeling and smart plantar pressure reconstruction from three sensors.

    PubMed

    Ghaida, Hussein Abou; Mottet, Serge; Goujon, Jean-Marc

    2014-01-01

    In order to monitor pressure under feet, this study presents a biomechanical model of the human foot. The main elements of the foot that induce the plantar pressure distribution are described. Then the link between the forces applied at the ankle and the distribution of the plantar pressure is established. Assumptions are made by defining the concepts of a 3D internal foot shape, which can be extracted from the plantar pressure measurements, and a uniform elastic medium, which describes the soft tissues behaviour. In a second part, we show that just 3 discrete pressure sensors per foot are enough to generate real time plantar pressure cartographies in the standing position or during walking. Finally, the generated cartographies are compared with pressure cartographies issued from the F-SCAN system. The results show 0.01 daN (2% of full scale) average error, in the standing position.

  5. Relationship between magnitude of applied torque in pre-swing phase and gait change for prevention of trip in elderly people.

    PubMed

    Miyake, Tamon; Tsukune, Mariko; Kobayashi, Yo; Sugano, Shigeki; Fujie, Masakatsu G

    2016-08-01

    Elderly people are at risk of tripping because of their narrow range of articular motion. To avoid tripping, gait training that improves their range of articular motion would be beneficial. In this study we propose a gait-training robot that applies a torque during the pre-swing phase to achieve this goal. We investigated the relationship between magnitude of applied torque and change in the range of knee-articular motion while walking before and after the application of this torque. We developed a wearable robot and carried out an experiment on human participants in which a motor pulls a string embedded on the robotic frame, applying torque in the pre-swing phase for a period of 20 [s]. Before and after applying torque the participant walked normally for 15 [s] without interference from the robot. We found that knee flexion angle increased after applying the torque if the torque was within the range of approximately 6-8 [Nm]. Therefore, we were able to verify that a new range of knee articular motion can be learned through application of torque.

  6. Torque-angle-velocity Relationships and Muscle Performance of Professional and Youth Soccer Players.

    PubMed

    Mazuquin, B F; Dela Bela, L F; Pelegrinelli, A R M; Dias, J M; Carregaro, R L; Moura, F A; Selfe, J; Richards, J; Brown, L E; Cardoso, J R

    2016-11-01

    Soccer matches consist of a variety of different activities, including repeated sprints. Time to attain velocity (TTAV), load range (LR) and the torque-angle-velocity relationship (TAV 3D ) represent an important measurement of muscle performance, however there are few related studies. The aim of this study was to compare these outcomes between soccer players of different age category. 17 professional (PRO) and 17 under-17 (U17) soccer players were assessed for concentric knee flexion/extension at 60, 120 and 300°/s. For the extensor muscles, differences were found in favor of the U17 group for TTAV and LR outcomes at 120°/s, however, the PRO group maintained higher torques in both movement directions in comparison to the U17 in TAV 3D evaluation. These results suggest that muscle performance of the PRO group is more efficient than the U17 group. © Georg Thieme Verlag KG Stuttgart · New York.

  7. Palmar and plantar pustulosis elicited by Candida antigen.

    PubMed

    Uehara, M

    1978-05-01

    Intracutaneous injection of Candida albicans was done on the forearm of 30 patients with palmar and plantar pustulosis. This induced an aggravation of pustular eruptions on the palms and soles in 11 (37%) of the 30 patients. The aggravation occurred only in those patients who had a positive delayed skin reaction to the Candida antigen. It is suggested that a delayed hypersensitivity inflammatory reaction somewhere in the body is attended with an aggravation of palmar plantar pustulosis.

  8. Variation of plantar pressure in Chinese diabetes mellitus.

    PubMed

    Yang, Chuan; Xiao, Huisheng; Wang, Chuan; Mai, LiFang; Liu, Dan; Qi, Yiqing; Ren, Meng; Yan, Li

    2015-01-01

    To investigate dynamic changes in plantar pressure in Chinese diabetes mellitus patients and to provide a basis for further preventing diabetic foot. This is a cross-sectional investigation including 649 Chinese diabetes mellitus patients (diabetes group) and 808 "normal" Chinese persons (nondiabetes group) with normal blood glucose levels. All the subjects provided a complete medical history and underwent a physical examination and a 75-g oral glucose tolerance test. All subjects walked barefoot with their usual gait, and their dynamic plantar forces were measured using the one-step method with a plantar pressure measurement instrument; 5 measurements were performed for each foot. No significant differences were found in age, height, body weight, or body mass index between the two groups. The fasting blood glucose levels, plantar contact time, maximum force, pressure-time integrals and force-time integrals in the diabetes group were significantly higher than those in the nondiabetes group (p < 0.05). However, the maximum pressure was significantly higher in the nondiabetes group than in the diabetes group (p < 0.05). No difference was found in the contact areas between the two groups (p > 0.05). The maximum plantar force distributions were essentially the same, with the highest force found for the medial heel, followed by the medial forefoot and the first toe. The peak plantar pressure was located at the medial forefoot for the nondiabetes group and at the hallucis for the diabetes group. In the diabetes group, the momentum in each plantar region was higher than that in the nondiabetes group; this difference was especially apparent in the heel, the lateral forefoot and the hallucis. The dynamic plantar pressures in diabetic patients differ from those in nondiabetic people with increased maximum force and pressure, a different distribution pattern and significantly increased momentum, which may lead to the formation of foot ulcers. © 2015 by the Wound

  9. Knee-Extension Torque Variability and Subjective Knee Function in Patients with a History of Anterior Cruciate Ligament Reconstruction.

    PubMed

    Goetschius, John; Hart, Joseph M

    2016-01-01

    When returning to physical activity, patients with a history of anterior cruciate ligament reconstruction (ACL-R) often experience limitations in knee-joint function that may be due to chronic impairments in quadriceps motor control. Assessment of knee-extension torque variability may demonstrate underlying impairments in quadriceps motor control in patients with a history of ACL-R. To identify differences in maximal isometric knee-extension torque variability between knees that have undergone ACL-R and healthy knees and to determine the relationship between knee-extension torque variability and self-reported knee function in patients with a history of ACL-R. Descriptive laboratory study. Laboratory. A total of 53 individuals with primary, unilateral ACL-R (age = 23.4 ± 4.9 years, height = 1.7 ± 0.1 m, mass = 74.6 ± 14.8 kg) and 50 individuals with no history of substantial lower extremity injury or surgery who served as controls (age = 23.3 ± 4.4 years, height = 1.7 ± 0.1 m, mass = 67.4 ± 13.2 kg). Torque variability, strength, and central activation ratio (CAR) were calculated from 3-second maximal knee-extension contraction trials (90° of flexion) with a superimposed electrical stimulus. All participants completed the International Knee Documentation Committee (IKDC) Subjective Knee Evaluation Form, and we determined the number of months after surgery. Group differences were assessed using independent-samples t tests. Correlation coefficients were calculated among torque variability, strength, CAR, months after surgery, and IKDC scores. Torque variability, strength, CAR, and months after surgery were regressed on IKDC scores using stepwise, multiple linear regression. Torque variability was greater and strength, CAR, and IKDC scores were lower in the ACL-R group than in the control group (P < .05). Torque variability and strength were correlated with IKDC scores (P < .05). Torque variability, strength, and CAR were correlated with each other (P < .05

  10. EMG-Torque Relation in Chronic Stroke: A Novel EMG Complexity Representation With a Linear Electrode Array.

    PubMed

    Zhang, Xu; Wang, Dongqing; Yu, Zaiyang; Chen, Xiang; Li, Sheng; Zhou, Ping

    2017-11-01

    This study examines the electromyogram (EMG)-torque relation for chronic stroke survivors using a novel EMG complexity representation. Ten stroke subjects performed a series of submaximal isometric elbow flexion tasks using their affected and contralateral arms, respectively, while a 20-channel linear electrode array was used to record surface EMG from the biceps brachii muscles. The sample entropy (SampEn) of surface EMG signals was calculated with both global and local tolerance schemes. A regression analysis was performed between SampEn of each channel's surface EMG and elbow flexion torque. It was found that a linear regression can be used to well describe the relation between surface EMG SampEn and the torque. Each channel's root mean square (RMS) amplitude of surface EMG signal in the different torque level was computed to determine the channel with the highest EMG amplitude. The slope of the regression (observed from the channel with the highest EMG amplitude) was smaller on the impaired side than on the nonimpaired side in 8 of the 10 subjects, regardless of the tolerance scheme (global or local) and the range of torques (full or matched range) used for comparison. The surface EMG signals from the channels above the estimated muscle innervation zones demonstrated significantly lower levels of complexity compared with other channels between innervation zones and muscle tendons. The study provides a novel point of view of the EMG-torque relation in the complexity domain, and reveals its alterations post stroke, which are associated with complex neural and muscular changes post stroke. The slope difference between channels with regard to innervation zones also confirms the relevance of electrode position in surface EMG analysis.

  11. Can static foot posture measurements predict regional plantar surface area?

    PubMed

    McPoil, Thomas G; Haager, Mathew; Hilt, John; Klapheke, John; Martinez, Ray; VanSteenwyk, Cory; Weber, Nicholas; Cornwall, Mark W; Bade, Michael

    2014-12-01

    The intent of this study was to determine if the use of a single or combination of static foot posture measurements can be used to predict rearfoot, midfoot, and forefoot plantar surface area in individuals with pronated or normal foot types. Twelve foot measurements were collected on 52 individuals (mean age 25.8 years) with the change in midfoot width used to place subjects in a pronated or normal foot mobility group. Dynamic plantar contact area was collected during walking with a pressure sensor platform. The 12 measures were entered into a stepwise regression analysis to determine the optimal set of measures associated with regional plantar surface area. A two variable model was found to describe the relationship between the foot measurements and forefoot plantar contact area (r(2)=0.79, p<0.0001). A four variable model was found to describe the relationship between the foot measurements and midfoot plantar contact area (r(2)=0.85, p<0.0001) in those individuals with a 1.26cm or greater change in midfoot width. The results indicate that clinicians can use a combination of simple, reliable and time efficient foot measures to explain 79% and 85% of the plantar surface area in the forefoot and midfoot, respectively. Copyright © 2014 Elsevier Ltd. All rights reserved.

  12. Whole plantar nerve conduction study with disposable strip electrodes.

    PubMed

    Hemmi, Shoji; Kurokawa, Katsumi; Nagai, Taiji; Okamoto, Toshio; Murakami, Tatsufumi; Sunada, Yoshihide

    2016-02-01

    A new method to evaluate whole plantar nerve conduction with disposable strip electrodes (DSEs) is described. Whole plantar compound nerve action potentials (CNAPs) were recorded at the ankle. DSEs were attached to the sole for simultaneous stimulation of medial and lateral plantar nerves. We also conducted medial plantar nerve conduction studies using an established method and compared the findings. Whole plantar CNAPs were recorded bilaterally from 32 healthy volunteers. Mean baseline to peak amplitude for CNAPs was 26.9 ± 11.8 μV, and mean maximum conduction velocity was 65.8 ± 8.3 m/s. The mean amplitude of CNAPs obtained by our method was 58.2% higher than that of CNAPs obtained by the Saeed method (26.9 μV vs. 17.0 μV; P < 0.0001). The higher mean amplitude of whole plantar CNAPs obtained by our method suggests that it enables CNAPs to be obtained easily, even in elderly people. © 2015 Wiley Periodicals, Inc.

  13. Is There a Role for MRI in Plantar Heel Pain.

    PubMed

    Fazal, Muhammad Ali; Tsekes, Demetris; Baloch, Irshad

    2018-06-01

    There is an increasing trend to investigate plantar heel pain with magnetic resonance imaging (MRI) scan though plantar fasciitis is the most common cause. The purpose of our study was to evaluate the role of MRI in patients presenting with plantar heel pain. Case notes and MRI scans of 141 patients with a clinical diagnosis of plantar fasciitis were reviewed retrospectively. There were 98 females and 43 males patients. Fourteen patients had bilateral symptoms. Average age for male patients was 51 years (range = 26-78 years), and for female patients the average age was 52 years (range = 29-76 years). A total of 121 feet had MRI features suggestive of plantar fasciitis. MRI was normal in 32 feet. There was one case of stress fracture of calcaneus and another of a heel fibroma diagnosed on MRI scan. In our study, MRI scan was normal in 20.7% of the cases; 1.3% had a diagnosis other than plantar fasciitis but no sinister pathology. We therefore conclude that MRI scan is not routinely indicated and key is careful clinical assessment. Therapeutic, Level IV: Retrospective, Case series.

  14. Discrete sensors distribution for accurate plantar pressure analyses.

    PubMed

    Claverie, Laetitia; Ille, Anne; Moretto, Pierre

    2016-12-01

    The aim of this study was to determine the distribution of discrete sensors under the footprint for accurate plantar pressure analyses. For this purpose, two different sensor layouts have been tested and compared, to determine which was the most accurate to monitor plantar pressure with wireless devices in research and/or clinical practice. Ten healthy volunteers participated in the study (age range: 23-58 years). The barycenter of pressures (BoP) determined from the plantar pressure system (W-inshoe®) was compared to the center of pressures (CoP) determined from a force platform (AMTI) in the medial-lateral (ML) and anterior-posterior (AP) directions. Then, the vertical ground reaction force (vGRF) obtained from both W-inshoe® and force platform was compared for both layouts for each subject. The BoP and vGRF determined from the plantar pressure system data showed good correlation (SCC) with those determined from the force platform data, notably for the second sensor organization (ML SCC= 0.95; AP SCC=0.99; vGRF SCC=0.91). The study demonstrates that an adjusted placement of removable sensors is key to accurate plantar pressure analyses. These results are promising for a plantar pressure recording outside clinical or laboratory settings, for long time monitoring, real time feedback or for whatever activity requiring a low-cost system. Copyright © 2016 IPEM. Published by Elsevier Ltd. All rights reserved.

  15. In-shoe plantar tri-axial stress profiles during maximum-effort cutting maneuvers.

    PubMed

    Cong, Yan; Lam, Wing Kai; Cheung, Jason Tak-Man; Zhang, Ming

    2014-12-18

    Soft tissue injuries, such as anterior cruciate ligament rupture, ankle sprain and foot skin problems, frequently occur during cutting maneuvers. These injuries are often regarded as associated with abnormal joint torque and interfacial friction caused by excessive external and in-shoe shear forces. This study simultaneously investigated the dynamic in-shoe localized plantar pressure and shear stress during lateral shuffling and 45° sidestep cutting maneuvers. Tri-axial force transducers were affixed at the first and second metatarsal heads, lateral forefoot, and heel regions in the midsole of a basketball shoe. Seventeen basketball players executed both cutting maneuvers with maximum efforts. Lateral shuffling cutting had a larger mediolateral braking force than 45° sidestep cutting. This large braking force was concentrated at the first metatarsal head, as indicated by its maximum medial shear stress (312.2 ± 157.0 kPa). During propulsion phase, peak shear stress occurred at the second metatarsal head (271.3 ± 124.3 kPa). Compared with lateral shuffling cutting, 45° sidestep cutting produced larger peak propulsion shear stress (463.0 ± 272.6 kPa) but smaller peak braking shear stress (184.8 ± 181.7 kPa), of which both were found at the first metatarsal head. During both cutting maneuvers, maximum medial and posterior shear stress occurred at the first metatarsal head, whereas maximum pressure occurred at the second metatarsal head. The first and second metatarsal heads sustained relatively high pressure and shear stress and were expected to be susceptible to plantar tissue discomfort or injury. Due to different stress distribution, distinct pressure and shear cushioning mechanisms in basketball footwear might be considered over different foot regions. Copyright © 2014 Elsevier Ltd. All rights reserved.

  16. Low-Torque Seal Development

    NASA Technical Reports Server (NTRS)

    Lattime, Scott B.; Borowski, Richard

    2009-01-01

    The EcoTurn Class K production prototypes have passed all AAR qualification tests and received conditional approval. The accelerated life test on the second set of seals is in progress. Due to the performance of the first set, no problems are expected.The seal has demonstrated superior performance over the HDL seal in the test lab with virtually zero torque and excellent contamination exclusion and grease retention.

  17. Extrinsic versus intrinsic hand muscle dominance in finger flexion.

    PubMed

    Al-Sukaini, A; Singh, H P; Dias, J J

    2016-05-01

    This study aims to identify the patterns of dominance of extrinsic or intrinsic muscles in finger flexion during initiation of finger curl and mid-finger flexion. We recorded 82 hands of healthy individuals (18-74 years) while flexing their fingers and tracked the finger joint angles of the little finger using video motion tracking. A total of 57 hands (69.5%) were classified as extrinsic dominant, where the finger flexion was initiated and maintained at proximal interphalangeal and distal interphalangeal joints. A total of 25 (30.5%) were classified as intrinsic dominant, where the finger flexion was initiated and maintained at the metacarpophalangeal joint. The distribution of age, sex, dominance, handedness and body mass index was similar in the two groups. This knowledge may allow clinicians to develop more efficient rehabilitation regimes, since intrinsic dominant individuals would not initiate extrinsic muscle contraction till later in finger flexion, and might therefore be allowed limited early active motion. For extrinsic dominant individuals, by contrast, initial contraction of extrinsic muscles would place increased stress on the tendon repair site if early motion were permitted. © The Author(s) 2016.

  18. Eliminating impingement optimizes patellar biomechanics in high knee flexion.

    PubMed

    Tang, Qi-heng; Zhou, Yi-xin; Tang, Jing; Shao, Hong-yi; Wang, Guang-zhi

    2010-08-01

    We investigated the impact of eliminating the impingement between extensor mechanism and tibial insert on patellar tracking and patellar ligament tension in high knee flexion. Six cadaveric specimens were tested on an Oxford-type testing rig. The Genesis II knee system was implanted into each specimen knee with the traditional tibial insert and high-flex insert successively. Compared to traditional insert, the high-flex insert was characterized with a chambered anterior post and a chambered anterior lip which eliminates patella-post and patellar ligament-anterior lip impingements. The patella was tracked with an NDI Optotrak Certus system. The patellar ligament tension was measured using a NKB S-type tension transducer. There was a decrease of resultant patellar translation relative to the femur with statistically significant (P<0.05) at 90 degrees to 150 degrees of knee flexion and a decrease of patellar ligament tension with statistical significance (P<0.05) at 100 degrees, 120 degrees, 130 degrees, and 140 degrees of flexion using high-flex insert compared to traditional insert. Eliminating the impingement between extensor mechanism and implant in high knee flexion altered patellar tracking and reduced patellar ligament tension, which would facilitate high knee flexion.

  19. Use of MRI for volume estimation of tibialis posterior and plantar intrinsic foot muscles in healthy and chronic plantar fasciitis limbs.

    PubMed

    Chang, Ryan; Kent-Braun, Jane A; Hamill, Joseph

    2012-06-01

    Due to complexity of the plantar intrinsic foot muscles, little is known about their muscle architecture in vivo. Chronic plantar fasciitis may be accompanied by muscle atrophy of plantar intrinsic foot muscles and tibialis posterior compromising the dynamic support of the foot prolonging the injury. Magnetic resonance images of the foot may be digitized to quantify muscle architecture. The first purpose of this study was to estimate in vivo the volume and distribution of healthy plantar intrinsic foot muscles. The second purpose was to determine whether chronic plantar fasciitis is accompanied by atrophy of plantar intrinsic foot muscles and tibialis posterior. Magnetic resonance images were taken bilaterally in eight subjects with unilateral plantar fasciitis. Muscle perimeters were digitally outlined and muscle signal intensity thresholds were determined for each image for volume computation. The mean volume of contractile tissue in healthy plantar intrinsic foot muscles was 113.3 cm(3). Forefoot volumes of plantar fasciitis plantar intrinsic foot muscles were 5.2% smaller than healthy feet (P=0.03, ES=0.26), but rearfoot (P=0.26, ES=0.08) and total foot volumes (P=0.07) were similar. No differences were observed in tibialis posterior size. While the total volume of plantar intrinsic foot muscles was similar in healthy and plantar fasciitis feet, atrophy of the forefoot plantar intrinsic foot muscles may contribute to plantar fasciitis by destabilizing the medial longitudinal arch. These results suggest that magnetic resonance imaging measures may be useful in understanding the etiology and rehabilitation of chronic plantar fasciitis. Copyright © 2011 Elsevier Ltd. All rights reserved.

  20. Spin Transfer Torque in Graphene

    NASA Astrophysics Data System (ADS)

    Lin, Chia-Ching; Chen, Zhihong

    2014-03-01

    Graphene is an idea channel material for spin transport due to its long spin diffusion length. To develop graphene based spin logic, it is important to demonstrate spin transfer torque in graphene. Here, we report the experimental measurement of spin transfer torque in graphene nonlocal spin valve devices. Assisted by a small external in-plane magnetic field, the magnetization reversal of the receiving magnet is induced by pure spin diffusion currents from the injector magnet. The magnetization switching is reversible between parallel and antiparallel configurations by controlling the polarity of the applied charged currents. Current induced heating and Oersted field from the nonlocal charge flow have also been excluded in this study. Next, we further enhance the spin angular momentum absorption at the interface of the receiving magnet and graphene channel by removing the tunneling barrier in the receiving magnet. The device with a tunneling barrier only at the injector magnet shows a comparable nonlocal spin valve signal but lower electrical noise. Moreover, in the same preset condition, the critical charge current density for spin torque in the single tunneling barrier device shows a substantial reduction if compared to the double tunneling barrier device.

  1. Space Suit Joint Torque Testing

    NASA Technical Reports Server (NTRS)

    Valish, Dana J.

    2011-01-01

    In 2009 and early 2010, a test was performed to quantify the torque required to manipulate joints in several existing operational and prototype space suits in an effort to develop joint torque requirements appropriate for a new Constellation Program space suit system. The same test method was levied on the Constellation space suit contractors to verify that their suit design meets the requirements. However, because the original test was set up and conducted by a single test operator there was some question as to whether this method was repeatable enough to be considered a standard verification method for Constellation or other future space suits. In order to validate the method itself, a representative subset of the previous test was repeated, using the same information that would be available to space suit contractors, but set up and conducted by someone not familiar with the previous test. The resultant data was compared using graphical and statistical analysis and a variance in torque values for some of the tested joints was apparent. Potential variables that could have affected the data were identified and re-testing was conducted in an attempt to eliminate these variables. The results of the retest will be used to determine if further testing and modification is necessary before the method can be validated.

  2. Shall We Inject Superficial or Deep to the Plantar Fascia? An Ultrasound Study of the Treatment of Chronic Plantar Fasciitis.

    PubMed

    Gurcay, Eda; Kara, Murat; Karaahmet, Ozgur Zeliha; Ata, Ayşe Merve; Onat, Şule Şahin; Özçakar, Levent

    We compared the effectiveness of ultrasound (US)-guided corticosteroid, injected superficial or deep to the fascia, in patients with plantar fasciitis. Thirty patients (24 females [75%] and 6 males [25%]) with unilateral chronic plantar fasciitis were divided into 2 groups according to the corticosteroid injection site: superficial (n = 15) or deep (n = 15) to the plantar fascia. Patient heel pain was measured using a Likert pain scale and the Foot Ankle Outcome Scale (FAOS) for foot disability, evaluated at baseline and repeated in the first and sixth weeks. The plantar fascia and heel pad thicknesses were assessed on US scans at baseline and the sixth week. The groups were similar in age, gender, and body mass index (p > .05 for all). Compared with the baseline values, the Likert pain scale (p < .001 for all) and FAOS subscale (p < .01 for all) scores had improved at the first and sixth week follow-up visits in both groups. Although the plantar fascia thickness had decreased significantly in both groups at the sixth week (p < .001 for both), the heel pad thickness remained unchanged (p > .05 for both). The difference in the FAOS subscales (pain, p = .002; activities of daily living, p = .003; sports/recreational activities, p = .008; quality of life, p = .009) and plantar fascia thickness (p = .049) showed better improvement in the deep than in the superficial injection group. US-guided corticosteroid injections are safe and effective in the short-term therapeutic outcome of chronic plantar fasciitis. Additionally, injection of corticosteroid deep to the fascia might result in greater reduction in plantar fascia thickness, pain, and disability and improved foot-related quality of life. Copyright © 2017 American College of Foot and Ankle Surgeons. Published by Elsevier Inc. All rights reserved.

  3. An Electromyographic-driven Musculoskeletal Torque Model using Neuro-Fuzzy System Identification: A Case Study

    PubMed Central

    Jafari, Zohreh; Edrisi, Mehdi; Marateb, Hamid Reza

    2014-01-01

    The purpose of this study was to estimate the torque from high-density surface electromyography signals of biceps brachii, brachioradialis, and the medial and lateral heads of triceps brachii muscles during moderate-to-high isometric elbow flexion-extension. The elbow torque was estimated in two following steps: First, surface electromyography (EMG) amplitudes were estimated using principal component analysis, and then a fuzzy model was proposed to illustrate the relationship between the EMG amplitudes and the measured torque signal. A neuro-fuzzy method, with which the optimum number of rules could be estimated, was used to identify the model with suitable complexity. Utilizing the proposed neuro-fuzzy model, the clinical interpretability was introduced; contrary to the previous linear and nonlinear black-box system identification models. It also reduced the estimation error compared with that of the most recent and accurate nonlinear dynamic model introduced in the literature. The optimum number of the rules for all trials was 4 ± 1, that might be related to motor control strategies and the % variance accounted for criterion was 96.40 ± 3.38 which in fact showed considerable improvement compared with the previous methods. The proposed method is thus a promising new tool for EMG-Torque modeling in clinical applications. PMID:25426427

  4. Within- and between-session reliability of the maximal voluntary knee extension torque and activation.

    PubMed

    Park, Jihong; Hopkins, J Ty

    2013-01-01

    A ratio between the torque generated by maximal voluntary isometric contraction (MVIC) and exogenous electrical stimulus, central activation ratio (CAR), has been widely used to assess quadriceps function. To date, no data exist regarding between-session reliability of this measurement. Thirteen neurologically sound volunteers underwent three testing sessions (three trials per session) with 48 hours between-session. Subjects performed MVICs of the quadriceps with the knee locked at 90° flexion and the hip at 85°. Once the MVIC reached a plateau, an electrical stimulation from superimposed burst technique (SIB: 125 V with peak output current 450 mA) was manually delivered and transmitted directly to the quadriceps via stimulating electrodes. CAR was calculated by using the following equation: CAR = MVIC torque/MVIC + SIB torque. Intraclass correlation coefficients (ICC) were calculated within- (ICC((2,1))) and between-session (ICC((2,k))) for MVIC torques and CAR values. Our data show that quadriceps MVIC and CAR are very reliable both within- (ICC((2,1)) = 0.99 for MVIC; 0.94 for CAR) and between-measurement sessions (ICC((2,k)) = 0.92 for MVIC; 0.86 for CAR) in healthy young adults. For clinical research, more data of the patients with pathological conditions are required to ensure reproducibility of calculation of CAR.

  5. Torque of the shank rotating muscles in patients with knee joint injuries.

    PubMed

    Hrycyna, Mariusz; Zieliński, Jacek

    2011-01-01

    The aim of the study was to evaluate the torque of the shank rotating muscles in patients with reconstructed anterior cruciate ligament (ACL) and rehabilitation accomplished in comparison with a control group. The study was carried out on the group of 187 males. For the purpose of the study a prototype testing device for the shank rotating muscles' torque under static conditions was used. The study was based on the measurement of maximal torque at selected angles (-30°, 0°, 45°) of the shank rotation as well as on the angle (30°, 60°, 90°) of flexion of the knee joint. The results obtained in the group with reconstructed anterior cruciate ligament (ACL) and rehabilitation accomplished were comparable to those the control group and mostly of no statistical significance. Lack of significant differences between the values of shank rotating muscles' torque achieved in an injured limb compared to an uninjured one may testify to an effective rehabilitation process. The results of the research can serve as a diagnostic tool for the rehabilitation process development.

  6. Plantar skin in type II diabetes: an investigation of protein glycation and biomechanical properties of plantar epidermis.

    PubMed

    Hashmi, Farina; Malone-Lee, James; Hounsell, Elizabeth

    2006-01-01

    The generation of thickened plantar stratum corneum (SC) in response to elevated pressures, places individuals with diabetes at risk of ulceration. Such a response may culminate from altered biochemical and physical states of the epidermis as a result of non-enzymatic glycation (NEG). The objective of this study was to quantify specific glycation products generated in plantar epidermal proteins in individuals with Type 2 Diabetes Mellitus (T2DM) and age-matched controls (n = 103 and n = 87, respectively) and to compare these data with the viscoelastic properties (in vivo) of the epidermis. Plantar SC and venous blood samples were collected from all participants for the quantification of furosine and pentosidine using high performance liquid chromatography (HPLC). The viscoelastic properties of plantar epidermis were measured by the application of negative pressure on the surface of the skin. Plantar epidermal thickness was measured using high frequency (20 MHz) ultrasonography. There was a significantly greater concentration of pentosidine in the SC samples from people with T2DM (p = 0.001). There was no correlation between the concentration of glycated proteins in the epidermal proteins and serum proteins (furosine r = - 0.115, pentosidine r = - 0.023). The plasticity of the epidermis was significantly lower in the T2DM group than the control group (p = 0.007). The results suggest that alterations in the glycation of plantar epidermal proteins may constitute additional aggravators of ulceration in people with T2DM.

  7. Associations of maximal voluntary isometric hip extension torque with muscle size of hamstring and gluteus maximus and intra-abdominal pressure.

    PubMed

    Tayashiki, Kota; Hirata, Kosuke; Ishida, Kiraku; Kanehisa, Hiroaki; Miyamoto, Naokazu

    2017-06-01

    Muscle size of the hamstring and gluteus maximus (GM) as well as intra-abdominal pressure (IAP) are considered as factors affecting the torque development during hip extension. This study examined the associations of torque development during maximal voluntary isometric hip extension with IAP and muscle size of the hamstring and GM. Anatomical cross-sectional area (ACSA) of the hamstring and thickness of GM were determined in 20 healthy young males using an ultrasonography apparatus (Experiment 1). Torque and IAP were simultaneously measured while subjects performed maximal voluntary isometric hip extension. The IAP was measured using a pressure transducer placed in the rectum and determined at the time at which the developed torque reached to the maximal. In Experiment 2, torque and IAP were measured during maximal voluntary isometric hip flexion in 18 healthy young males. The maximal hip extension torque was significantly correlated with the IAP (r = 0.504, P = 0.024), not with the ACSA of the hamstring (r = 0.307, P = 0.188) or the thickness of GM (r = 0.405, P = 0.076). The relationship was still significant even when the ACSA of the hamstring and the thickness of GM were adjusted statistically (r = 0.486, P = 0.041). The maximal hip flexion torque was not significantly correlated with the IAP (r = -0.118, P = 0.642). The current results suggest that IAP can contribute independently of the muscle size of the agonists to maximal voluntary hip extension torque.

  8. Validation of Plantar Pressure Measurements for a Novel In-Shoe Plantar Sensory Replacement Unit

    PubMed Central

    Ferber, Reed; Webber, Talia; Kin, B; Everett, Breanne; Groenland, Marcel

    2013-01-01

    Background Research concerning prevention of diabetic foot complications is critical. A novel in-shoe plantar sensory replacement unit (PSRU) has been developed that provides alert-based feedback derived from analyzing plantar pressure threshold measurements in real time. The purpose of this study was to compare the PSRU device to a gold standard pressure-sensing device (GS-PSD) to determine the correlation between concurrent measures of plantar pressure during walking. Methods The PSRU had an array of eight sensors with a range of 10–75 mm Hg and collected data at 4 Hz, whereas the GS-PSD had 99 sensors with a range of 1–112 mm Hg and collected data at 100 Hz. Based on an a priori power analysis, data were collected from 10 participants (3 female, 7 male) while walking over ground in both devices. The primary variable of interest was the number of data points recorded that were greater than 32 mm Hg (capillary arterial pressure—the minimum pressure reported to cause pressure ulcers) for each of the eight PSRU sensors and corresponding average recordings from the GS-PSD sensor clusters. Intraclass correlation coefficient (2,1) was used to compare data between the two devices. Results Compared with the GS-PSD, we found good-to-very-good correlations (r-value range 0.67–0.86; p-value range 0.01–0.05) for six of the PSRU’s eight sensors and poor correlation for only two sensors (r = 0.41, p = .15; r = 0.38, p = .18) when measuring the number of data points recorded that were greater than 32 mm Hg. Conclusions Based on the results of the present study, we conclude the PSRU provides analogous data when compared with a GS-PSD. PMID:24124942

  9. Endoscopic plantar fasciotomy versus extracorporeal shock wave therapy for treatment of chronic plantar fasciitis

    PubMed Central

    Ragab, Ehab Mohamed

    2009-01-01

    Background Planter fasciitis is a common cause of heel pain in adults. Many treatment options exist. Most of patients resolve with conservative management. Approximately 10% of patients develop persistent and often disabling symptoms. Patients and methods This prospective study includes 37 patients with an established diagnosis of chronic plantar fasciitis, aiming to compare two different techniques of treatment. First group includes 17 patients with a mean age of 42 years treated by endoscopic plantar fasciotomy (EPF); the mean follow-up was 11 months. Second group includes 20 patients with a mean age of 45 years treated by extracorporeal shock Wave Therapy (ESWT); the mean follow-up was 7.6 months. Results In the first group (EPF), using the visual analog scale the average post-operative pain was improved from 9.1 to 1.6. Post-operatively, 58.8% had no limitation of functional activities, 35.3% had minimal limitation of activities and 5.9% had moderate limitation of activities. Concerning patient satisfaction, 82.3% of patients were completely satisfied, 11.8% of patients were satisfied with reservation and 5.9% of patients were unsatisfied. For the second group (ESWT), using the visual analog scale the average post-operative pain was improved from 9 to 2.1. Post-operatively, 50% had no functional limitation of activities, 35% had minimal limitation of activities, 10% had moderate limitation of activities, and 5% had severe limitation of activities. Concerning patient satisfaction, 75% of patients were completely satisfied and 25% were satisfied with reservation or unsatisfied. Conclusion Because of better results with endoscopic release versus the benefits of no complications, no immobilization, and early resumption of full activities with ESWT, we conclude that ESWT is a reasonable earlier line of treatment of chronic plantar fasciitis before EPF. PMID:20033696

  10. Continuous passive motion with accelerated flexion after total knee arthroplasty.

    PubMed

    Yashar, A A; Venn-Watson, E; Welsh, T; Colwell, C W; Lotke, P

    1997-12-01

    The use of continuous passive motion after total knee arthroplasty remains controversial. A new approach, starting continuous passive motion at 70 degrees to 100 degrees flexion in the recovery room (Group I) was evaluated. A randomized, prospective study of 210 consecutive total knee arthroplasties was performed at two institutions. The control population (Group II) started continuous passive motion at 0 degree to 30 degrees, and progressed toward 100 degrees flexion. Flexion at postoperative Day 3 (Group I = 82.5 degrees, Group II = 72.8 degrees), and at discharge (Group I = 89.1 degrees, Group II = 84.3 degrees) were significantly different. There was no significant difference between the groups at 4 weeks (Group I = 5.0 degrees-104.1 degrees, Group II = 5.6 degrees-102.0 degrees), 6 weeks (Group I = 2.3 degrees-104.8 degrees, Group II = 2.7 degrees-103.6 degrees), 12 weeks (Group I = 1.7 degrees-107.7 degrees, Group II = 4.7 degrees-108.2 degrees), or at 1 year (Group I = 0.5 degree-113.2 degrees, Group II = 1.8 degrees-110.5 degrees). In Group I, wound necrosis developed in one patient that required a gastrocnemius flap. This major complication was caused by a tight dressing, and not necessarily to the accelerated flexion continuous passive motion. This investigation shows that continuous passive motion using accelerated flexion allows increased flexion during the hospital stay without increased risk of complications, pain, or blood loss. This has significant implications for achieving safe, early discharge. However, no difference was found at followup of 4 weeks or greater, and this did not add significantly to the final outcome.

  11. The Artificial Gravity Bed Rest Pilot Project: Effects on Knee Extensor and Plantar Flexor Muscle Groups

    NASA Technical Reports Server (NTRS)

    Caiozzo, V. J.; Haddad, F.; Lee, S.; Baker, M.; Baldwin, K. M.

    2007-01-01

    The goal of this project was to examine the effects of artificial gravity (2.5 g) on skeletal muscle strength and key anabolic/catabolic markers known to regulate muscle mass. Two groups of subjects were selected for study: 1) a 21 day-bed rest (BR) control (C) group (N=7); and 2) an AG group (N=8), which was exposed to 21 days of bed-rest plus daily 1 hr exposures to AG (2.5 g). This particular experiment was part of an integrated AG Pilot Project sponsored by NASA/Johnson Space Center. The in vivo torque-velocity relationships of the knee extensors and plantar flexors of the ankle were determined pre and post treatment. Also, pre- and post treatment biopsy samples were obtained from both the vastus lateralis and soleus muscles and were used, in part, for a series of analyses on gene expression (mRNA abundance) of key factors implicated in the anabolic versus catabolic state of the muscle. Post/Pre toque-velocity determinations revealed greater decrements in knee extensor performance in the C versus AG group (P less than 0.04). The plantar flexor muscle group of the AG subjects actually demonstrated a net gain in torque-velocity relationship; whereas, in the C group the overall post/pre responses declined (AG vs C; P less than 0.001). Measurements of muscle fiber cross-sectional area (for both muscles) demonstrated a loss of approx. 20% in the C group while no losses were evident in the AG group. RT-PCR analyses of muscle biopsy specimens demonstrated that markers of growth and cytoskeletal integrity (IGF-1, IGF-1 BP4, mechano growth factor, total RNA, and pro-collagen 3a) were higher in the AG group, whereas catabolic markers (myostatin and atrogen) were elevated in the C group. Importantly, these patterns were seen in both muscles. Based on these observations we conclude that paradigms of AG have the potential to maintain the functional, biochemical, and structural homeostasis of skeletal muscle in the face of chronic unloading states. These findings also

  12. Evaluation of Vertical Integrated Nanogenerator Performances in Flexion

    NASA Astrophysics Data System (ADS)

    Tao, R.; Hinchet, R.; Ardila, G.; Mouis, M.

    2013-12-01

    Piezoelectric nanowires have attracted great interest as new building blocks of mechanical energy harvesting systems. This paper presents the design improvements of mechanical energy harvesters integrating vertical ZnO piezoelectric nanowires onto a Silicon or plastic membrane. We have calculated the energy generation and conversion performance of ZnO nanowires based vertical integrated nanogenerators in flexion mode. We show that in flexion mode ZnO nanowires are superior to bulk ZnO layer. Both mechanical and electrical effects of matrix materials on the potential generation and energy conversion are discussed, in the aim of guiding further improvement of nanogenerator performance.

  13. Neuromuscular adjustments of the knee extensors and plantar flexors following match-play tennis in the heat

    PubMed Central

    Périard, Julien D; Girard, Olivier; Racinais, Sébastien

    2014-01-01

    Objectives This study tested the hypothesis that impairments in lower limb maximal strength and voluntary activation (VA) are exacerbated following match-play tennis in hot compared with cool conditions. Methods Torque and VA were evaluated during brief (5 s) and sustained (20 s) maximal voluntary isometric contractions of the knee extensors (KE) and plantar flexors (PF) in 12 male tennis players before (pre) and after (post, 24 h and 48 h) ∼115 min of play in hot (∼37°C) and cool (∼22°C) conditions. Results Rectal temperature was higher following play in hot than in cool (∼39.2 vs ∼38.5°C; p<0.05). Torque production decreased from prematch to postmatch during the brief and sustained contractions in hot (KE: ∼22%; PF: ∼13%) and cool (KE: ∼9%, PF: ∼7%) (p<0.05). KE strength losses in hot were greater than in cool (p<0.05) and persisted for 24 h (p<0.05). Postmatch brief and sustained KE VA was lower in hot than in cool (p<0.05), in which VA was maintained. PF VA was maintained throughout the protocol. Peak twitch torque and maximum rates of torque development and relaxation in the KE and PF were equally reduced postmatch relative to prematch in hot and cool conditions (p<0.05), and were restored near baseline within 24 h. Conclusions Neuromuscular system integrity of the lower limbs is compromised immediately following match-play tennis in hot and cool conditions due to the development of peripheral fatigue. The larger and persistent KE strength losses observed under heat stress are associated with greater levels of central fatigue especially during sustained contractions. PMID:24668379

  14. Increasing preferred step rate during running reduces plantar pressures.

    PubMed

    Gerrard, James M; Bonanno, Daniel R

    2018-01-01

    Increasing preferred step rate during running is a commonly used strategy in the management of running-related injuries. This study investigated the effect of different step rates on plantar pressures during running. Thirty-two healthy runners ran at a comfortable speed on a treadmill at five step rates (preferred, ±5%, and ±10%). For each step rate, plantar pressure data were collected using the pedar-X in-shoe system. Compared to running with a preferred step rate, a 10% increase in step rate significantly reduced peak pressure (144.5±46.5 vs 129.3±51 kPa; P=.033) and maximum force (382.3±157.6 vs 334.0±159.8 N; P=.021) at the rearfoot, and reduced maximum force (426.4±130.4 vs 400.0±116.6 N; P=.001) at the midfoot. In contrast, a 10% decrease in step rate significantly increased peak pressure (144.5±46.5 vs 161.5±49.3 kPa; P=.011) and maximum force (382.3±157.6 vs 425.4±155.3 N; P=.032) at the rearfoot. Changing step rate by 5% provided no effect on plantar pressures, and no differences in plantar pressures were observed at the medial forefoot, lateral forefoot or hallux between the step rates. This study's findings indicate that increasing preferred step rate by 10% during running will reduce plantar pressures at the rearfoot and midfoot, while decreasing step rate by 10% will increase plantar pressures at the rearfoot. However, changing preferred step rate by 5% will provide no effect on plantar pressures, and forefoot pressures are unaffected by changes in step rate. © 2017 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

  15. Plantar keloids: diagnostic and therapeutic issues in six patients.

    PubMed

    Vanhaecke, C; Hickman, G; Cavelier-Balloy, B; Masson, V; Duron, J-B; Gorj, M; May, P; Schneider, P; Vilmer, C; Bagot, M; Battistella, M; Petit, A

    2015-07-01

    Keloids are benign fibro-proliferative skin lesions that very rarely occur on the soles. Because of their rarity, the diagnosis of plantar keloids can be difficult. We describe the clinical and histopathological characteristics of eight plantar keloids. All patients presenting with plantar keloids between 2005 and 2012 in our Dermatology unit were retrospectively included. Diagnosis was definitely established by re-reading of pathological slides in all cases. Clinical characteristics, histopathological features, treatments given and their results were collected. Six patients were included. Five patients had a single plantar keloid and one had three lesions. They all were of African descent. Only one patient remembered of a previous injury at the site of the keloid. Three patients presented with associated extra-plantar keloids. In four patients, the diagnosis of keloid was not initially suspected clinically or histologically. Re-reading of the clinical photographs showed that the eight plantar keloids shared common morphological features, leading to a distinctive clinical picture, defined by a hardened lesion of rounded or polycyclic shape, with a pink surface crossed by keratotic furrows and the presence of a hyperkeratotic rim. Concerning pathological features, typical hyalinized collagen can be missing and deep fibrosis should not rule out the diagnosis of keloid. Intralesional injection of triamcinolone acetonide and orthopaedic shoes were useful. All patients who had surgical excision presented recurrence. The knowledge of the clinical features of plantar keloids is helpful to the diagnosis. There is no well-established treatment, but supportive measures are important. © 2014 European Academy of Dermatology and Venereology.

  16. Prognostic Value of Diagnostic Sonography in Patients With Plantar Fasciitis.

    PubMed

    Fleischer, Adam E; Albright, Rachel H; Crews, Ryan T; Kelil, Tatiana; Wrobel, James S

    2015-10-01

    The primary objective of this study was to determine whether the sonographic appearance of the plantar fascia is predictive of the treatment (ie, pain) response in patients receiving supportive therapy for proximal plantar fasciitis. This study was a secondary analysis of data obtained from a randomized controlled trial of ambulatory adults, which examined the efficacy of 3 different foot supports for plantar fasciitis. Participants underwent diagnostic sonographic examinations of their heel at baseline and again at 3 months by a single experienced foot and ankle surgeon. Quantitative (eg, thickness) and qualitative (eg, biconvexity) characteristics of the fascia were recorded according to a standard protocol. Logistic regression models were used to identify predictors of the pain response. Seventy patients completed a baseline evaluation, and 63 patients completed a 3-month follow-up assessment. The pain response was not associated with the type of foot support (P> .05). The only significant indicator of an unfavorable response in the univariate and multivariate analyses was biconvexity of the plantar fascia on sonography at presentation (multivariate odds ratio, 4.76 [95% confidence interval, 1.16-19.5; P= .030). Furthermore, changes in self-reported pain over the 3-month study period were not accompanied by alterations in plantar fascia thickness over this time (r = .056; P = .671). We conclude that patients who present with biconvexity of the plantar fascia may be less responsive to tier 1 treatment regimens that center around mechanical support of the plantar fascia. Furthermore, follow-up measurements of the fascia in this population should not weigh heavily in decisions such as return to play. © 2015 by the American Institute of Ultrasound in Medicine.

  17. Reproducibility of the time to peak torque and the joint angle at peak torque on knee of young sportsmen on the isokinetic dynamometer.

    PubMed

    Bernard, P-L; Amato, M; Degache, F; Edouard, P; Ramdani, S; Blain, H; Calmels, P; Codine, P

    2012-05-01

    Although peak torque has shown acceptable reproducibility, this may not be the case with two other often used parameters: time to peak torque (TPT) and the angle of peak torque (APT). Those two parameters should be used for the characterization of muscular adaptations in athletes. The isokinetic performance of the knee extensors and flexors in both limbs was measured in 29 male athletes. The experimental protocol consisted of three consecutive identical paradigms separated by 45 min breaks. Each test consisted of four maximal concentric efforts performed at 60 and 180°/s. Reproducibility was quantified by the standard error measurement (SEM), the coefficient of variation (CV) and by means of intra-class correlation coefficients (ICCs) with the calculation of 6 forms of ICCs. Using ICC as the indicator of reproducibility, the correlations for TPT of both limbs showed a range of 0.51-0.65 in extension and 0.50-0.63 in flexion. For APT, the values were 0.46-0.60 and 0.51-0.81, respectively. In addition, the calculated standard error of measurement (SEM) and CV scores confirmed the low level of absolute reproducibility. Due to their low reproducibility, neither TPT nor APT can serve as independent isokinetic parameters of knee flexor and extensor performance. So, given its reproducibility level, TPT and APT should not be used for the characterization of muscular adaptations in athletes. Copyright © 2012 Elsevier Masson SAS. All rights reserved.

  18. Investigation of Motorcycle Steering Torque Components

    NASA Astrophysics Data System (ADS)

    Cossalter, V.; Lot, R.; Massaro, M.; Peretto, M.

    2011-10-01

    When driving along a circular path, the rider controls a motorcycle mainly by the steering torque. This work addresses an in-depth analysis of the steady state cornering and in particular the decomposition of the motorcycle steering torque in its main components, such as road-tyre forces, gyroscopic torques, centrifugal and gravity effects. A detailed and experimentally validated multibody model of the motorcycle is used herein to analyze the steering torque components at different speeds and lateral accelerations. First the road tests are compared with the numerical results for three different vehicles and then a numerical investigation is carried out to decompose the steering torque. Finally, the effect of longitudinal acceleration and deceleration on steering torque components is presented.

  19. Development of a Portable Torque Wrench Tester

    NASA Astrophysics Data System (ADS)

    Wang, Y.; Zhang, Q.; Gou, C.; Su, D.

    2018-03-01

    A portable torque wrench tester (PTWT) with calibration range from 0.5 Nm to 60 Nm has been developed and evaluated for periodic or on-site calibration of setting type torque wrenches, indicating type torque wrenches and hand torque screwdrivers. The PTWT is easy to carry with weight about 10 kg, simple and efficient operation and energy saving with an automatic loading and calibrating system. The relative expanded uncertainty of torque realized by the PTWT was estimated to be 0.8%, with the coverage factor k=2. A comparison experiment has been done between the PTWT and a reference torque standard at our laboratory. The consistency between these two devices under the claimed uncertainties was verified.

  20. Contact sensitivities in palmar plantar pustulosis (acropustulosis).

    PubMed

    Yiannias, J A; Winkelmann, R K; Connolly, S M

    1998-09-01

    Acropustulosis, or chronic palmar plantar pustulosis (PPP), is a phenomenon of recurrent sterile pustules, erythema, and scaling affecting the palms and soles. Its pathogenesis is unclear, and it is difficult to treat. The purpose of this study was to elucidate further the factors involved in causing PPP, thereby enhancing the ability to manage this disease. All cases of PPP seen at Mayo Clinic Scottsdale from 1987 to 1993 were reviewed. 21 patients with PPP were identified, 15 of whom had been patch tested. 9 of the 15 patients (60%) showed positive patch test results. Fragrance was the most common sensitivity, but nickel, formaldehyde, para-phenylenediamine, thiuram, neomycin, mercury, balsam of Peru, and cinnamic aldehyde sensitivities were demonstrated. Less important factors included atopy, fungal and bacterial infections, and irritation. Although the mechanism of this sterile pustulosis response does not depend solely on delayed hypersensitivity mechanisms, we believe that we have demonstrated such a large number of positive patch tests in this chronic pustular dermatosis that patch testing should be considered in the routine work-up of these patients.

  1. Heat-driven spin torques in antiferromagnets

    NASA Astrophysics Data System (ADS)

    Białek, Marcin; Bréchet, Sylvain; Ansermet, Jean-Philippe

    2018-04-01

    Heat-driven magnetization damping, which is a linear function of a temperature gradient, is predicted in antiferromagnets by considering the sublattice dynamics subjected to a heat-driven spin torque. This points to the possibility of achieving spin torque oscillator behavior. The model is based on the magnetic Seebeck effect acting on sublattices which are exchange coupled. The heat-driven spin torque is estimated and the feasibility of detecting this effect is discussed.

  2. Passive and active floating torque during swimming.

    PubMed

    Kjendlie, Per-Ludvik; Stallman, Robert Keig; Stray-Gundersen, James

    2004-10-01

    The purpose of this study was to examine the effect of passive underwater torque on active body angle with the horizontal during front crawl swimming and to assess the effect of body size on passive torque and active body angle. Additionally, the effects of passive torque, body angle and hydrostatic lift on maximal sprinting performance were addressed. Ten boys [aged 11.7 (0.8) years] and 12 male adult [aged 21.4 (3.7) years] swimmers volunteered to participate. Their body angle with the horizontal was measured at maximal velocity, and at two submaximal velocities using an underwater video camera system. Passive torque and hydrostatic lift were measured during an underwater weighing procedure, and the center of mass and center of volume were determined. The results showed that passive torque correlated significantly with the body angle at a velocity 63% of v(max) ( alpha(63) r=-0.57), and that size-normalized passive torque correlated significantly with the alpha(63) and alpha(77) (77% of v(max)) with r=-0.59 and r=-0.54 respectively. Hydrostatic lift correlated with alpha(63) with r=-0.45. The negative correlation coefficients are suggested to be due to the adults having learned to overcome passive torque when swimming at submaximal velocities by correcting their body angle. It is concluded that at higher velocities the passive torque and hydrostatic lift do not influence body angle during swimming. At a velocity of 63% of v(max), hydrostatic lift and passive torque influences body angle. Passive torque and size-normalized passive torque increases with body size. When corrected for body size, hydrostatic lift and passive torque did not influence the maximal sprinting velocity.

  3. Viscous Torques on a Levitating Body

    NASA Technical Reports Server (NTRS)

    Busse, F.; Wang, T.

    1982-01-01

    New analytical expressions for viscous torque generated by orthogonal sound waves agree well with experiment. It is possible to calculate torque on an object levitated in a fluid. Levitation has applications in containerless materials processing, coating, and fabrication of small precision parts. Sound waves cause fluid particles to move in elliptical paths and induce azimuthal circulation in boundary layer, giving rise to time-averaged torque.

  4. Zero-torque spanner wrench

    NASA Technical Reports Server (NTRS)

    Friedell, M. V.

    1980-01-01

    Wrench converts gripping action of hand to rotary motion without imparting reactive moments or forces on part being turned or on operator. Wrench should be useful in undersea operations and other delicate work where reactive forces and torques have to be controlled. In design for valve tightening, tool resembles cross between conventional spanner wrench and pilers. One handle engages valve body; second handle has ratchet pawl that engages toothed coupling ring on perimeter of valve handle. When operator squeezes wrench handles, valve handle rotates with respect to valve body.

  5. Effectiveness of the Simultaneous Stretching of the Achilles Tendon and Plantar Fascia in Individuals With Plantar Fasciitis.

    PubMed

    Engkananuwat, Phoomchai; Kanlayanaphotporn, Rotsalai; Purepong, Nithima

    2018-01-01

    Since the plantar fascia and the Achilles tendon are anatomically connected, it is plausible that stretching of both structures simultaneously will result in a better outcome for plantar fasciitis. Fifty participants aged 40 to 60 years with a history of plantar fasciitis greater than 1 month were recruited. They were prospectively randomized into 2 groups. Group 1 was instructed to stretch the Achilles tendon while group 2 simultaneously stretched the Achilles tendon and plantar fascia. After 4 weeks of both stretching protocols, participants in group 2 demonstrated a significantly greater pressure pain threshold than participants in group 1 ( P = .040) with post hoc analysis. No significant differences between groups were demonstrated in other variables ( P > .05). Concerning within-group comparisons, both interventions resulted in significant reductions in pain at first step in the morning and average pain at the medial plantar calcaneal region over the past 24 hours, while there were increases in the pressure pain threshold, visual analog scale-foot and ankle score, and range of motion in ankle dorsiflexion ( P < .001). More participants in group 2 described their symptoms as being much improved to being completely improved than those in group 1. The simultaneous stretching of the Achilles tendon and plantar fascia for 4 weeks was a more effective intervention for plantar fasciitis. Patients who reported complete relief from symptoms at the end of the 4-week intervention in the simultaneous stretching group (n = 14; 56%) were double that of the stretching of the Achilles tendon-only group (n = 7; 28%). II, lesser quality RCT or prospective comparative study.

  6. Torque limited drive for manual valves

    DOEpatents

    Elliott, Philip G.; Underwood, Daniel E.

    1989-06-06

    The present invention is directed to a torque-limiting handwheel device for preventing manual valves from being damaged due to the application of excessive torque during the opening or closing operation of the valves. Torque can only be applied when ridges in the handwheel assembly engage in channels machined in the face of the baseplate. The amount of torque required for disengagement of the ridges from the channels is determined by the force exerted by various Bellville springs and the inclination of the side faces of the channels.

  7. Torque limited drive for manual valves

    DOEpatents

    Elliott, Philip G.; Underwood, Daniel E.

    1989-01-01

    The present invention is directed to a torque-limiting handwheel device for preventing manual valves from being damaged due to the application of excessive torque during the opening or closing operation of the valves. Torque can only be applied when ridges in the handwheel assembly engage in channels machined in the face of the baseplate. The amount of torque required for disengagement of the ridges from the channels is determined by the force exerted by various Bellville springs and the inclination of the side faces of the channels.

  8. A comparative study of proximal hindlimb flexion in horses: 5 versus 60 seconds.

    PubMed

    Armentrout, A R; Beard, W L; White, B J; Lillich, J D

    2012-07-01

    The flexion test is routinely used in lameness and prepurchase examinations. There is no accepted standard for duration of flexion or evidence that interpretation of results would differ with different durations of flexion. There will be no difference in interpretation of proximal hindlimb flexion for 5 or 60 s. Video recordings of lameness examinations of 34 client-owned horses were performed that included: baseline lameness, proximal hindlimb flexion for 60 s, and flexion of the same limb for 5 s. Videos were edited to blind reviewers to the hypothesis being tested. The baseline lameness video from each horse was paired with each flexion to make 2 pairs of videos for each case. Twenty video pairs were repeated to assess intraobserver repeatability. Fifteen experienced equine clinicians were asked to review the baseline lameness video followed by the flexion test and grade the response to flexion as either positive or negative. Potential associations between the duration of flexion and the likelihood of a positive flexion test were evaluated using generalised linear mixed models. A kappa value was calculated to assess the degree of intraobserver agreement on the repeated videos. Significance level was set at P<0.05. Proximal hindlimb flexion of 60 s was more likely to be called positive than flexion of 5 s (P<0.0001), with the likelihood of the same interpretation 74% of the time. The first flexion performed was more likely to be called positive than subsequent flexions (P = 0.029). Intra-assessor agreement averaged 75% with κ= 0.49. Proximal hindlimb flexion of a limb for 5 s does not yield the same result as flexing a limb for 60 s. Shorter durations of flexion may be useful for clinicians that have good agreement with flexions of 5 and 60 s. © 2011 EVJ Ltd.

  9. Semimembranosus Release for Medial Soft Tissue Balancing Does Not Weaken Knee Flexion Strength in Patients Undergoing Varus Total Knee Arthroplasty.

    PubMed

    Jang, Sung Won; Koh, In Jun; Kim, Man Soo; Kim, Ju Yeong; In, Yong

    2016-11-01

    The sequential medial release technique including semimembranosus (semiM) release is effective and safe during varus total knee arthroplasty (TKA). However, there are concerns about weakening of knee flexion strength after semiM release. We determined whether semiM release to balance the medial soft tissue decreased knee flexion strength after TKA. Fifty-nine consecutive varus knees undergoing TKA were prospectively enrolled. A 3-step sequential release protocol which consisted of release of (1) the deep medial collateral ligament (dMCL), (2) the semiM, and (3) the superficial medial collateral ligament based on medial tightness. Gap balancing was obtained after dMCL release in 31 knees. However, 28 knees required semiM release or more after dMCL release. Isometric muscle strength of the knee was compared 6 months postoperatively between the semiM release and semiM nonrelease groups. Knee stability and clinical outcomes were also compared. No differences in knee flexor or extensor peak torque were observed between the groups 6 months postoperatively (P = .322 and P = .383, respectively). No group difference was observed in medial joint opening angle on valgus stress radiographs (P = .327). No differences in the Knee Society or Western Ontario and McMaster Universities Osteoarthritis Index scores were detected between the groups (P = .840 and P = .682, respectively). These results demonstrate that semiM release as a sequential step to balance medial soft tissue in varus knees did not affect knee flexion strength after TKA. Copyright © 2016 Elsevier Inc. All rights reserved.

  10. Resonance at the wrist demonstrated by the use of a torque motor: an instrumental analysis of muscle tone in man.

    PubMed Central

    Lakie, M; Walsh, E G; Wright, G W

    1984-01-01

    The resonance of the relaxed wrist for flexion-extension movements in the horizontal plane has been investigated by using rhythmic torques generated by a printed motor. In the normal subject the resonant frequency of the wrist is ca. 2 Hz unless the torque is reduced below a certain critical value when the system is no longer linear and the resonant frequency rises. This critical torque level, and the damping are both less in women than men. The resonant frequency is uninfluenced by surgical anaesthesia. With added bias the increase of resonant frequency at low torques still occurs although the hand is now oscillating about a displaced mean position. It follows that the stiffening implied by this elevation of resonant frequency for small movements is neither the result of pre-stressing of the muscles nor of reflex activity. With velocity feed-back of appropriate polarity the system will oscillate spontaneously at its resonant frequency. If the peak driving torque is progressively reduced the resonant frequency increases abruptly, indicating that the system has stiffened. Perturbations delivered to the wrist may reduce its stiffness. The postural system is thixotropic with a 'memory time' of 1-2 s. The resonant frequency is elevated in voluntary stiffening. PMID:6481624

  11. Effects of 1 week of unilateral ankle immobilization on plantar-flexor strength, balance, and walking speed: a pilot study in asymptomatic volunteers.

    PubMed

    Caplan, Nick; Forbes, Andrew; Radha, Sarkhell; Stewart, Su; Ewen, Alistair; St Clair Gibson, Alan; Kader, Deiary

    2015-05-01

    Ankle immobilization is often used after ankle injury. To determine the influence of 1 week's unilateral ankle immobilization on plantar-flexor strength, balance, and walking gait in asymptomatic volunteers. Repeated-measures laboratory study. University laboratory. 6 physically active male participants with no recent history of lower-limb injury. Participants completed a 1-wk period of ankle immobilization achieved through wearing a below-knee ankle cast. Before the cast was applied, as well as immediately, 24 h, and 48 h after cast removal, their plantar-flexor strength was assessed isokinetically, and they completed a single-leg balance task as a measure of proprioceptive function. An analysis of their walking gait was also completed Main Outcome Measures: Peak plantar-flexor torque and balance were used to determine any effect on muscle strength and proprioception after cast removal. Ranges of motion (3D) of the ankle, knee, and hip, as well as walking speed, were used to assess any influence on walking gait. After cast removal, plantar-flexor strength was reduced for the majority of participants (P = .063, CI = -33.98 to 1.31) and balance performance was reduced in the immobilized limb (P < .05, CI = 0.84-5.16). Both strength and balance were not significantly different from baseline levels by 48 h. Walking speed was not significantly different immediately after cast removal but increased progressively above baseline walking speed over the following 48 h. Joint ranges of motion were not significantly different at any time point. The reduction in strength and balance after such a short period of immobilization suggested compromised central and peripheral neural mechanisms. This suggestion appeared consistent with the delayed increase in walking speed that could occur as a result of the excitability of the neural pathways increasing toward baseline levels.

  12. Adult Hip Flexion Contracture due to Neurological Disease: A New Treatment Protocol—Surgical Treatment of Neurological Hip Flexion Contracture

    PubMed Central

    Nicodemo, Alberto; Arrigoni, Chiara; Bersano, Andrea; Massè, Alessandro

    2014-01-01

    Congenital, traumatic, or extrinsic causes can lead people to paraplegia; some of these are potentially; reversible and others are not. Paraplegia can couse hip flexion contracture and, consequently, pressure sores, scoliosis, and hyperlordosis; lumbar and groin pain are strictly correlated. Scientific literature contains many studies about children hip flexion related to neurological diseases, mainly caused by cerebral palsy; only few papers focus on this complication in adults. In this study we report our experience on surgical treatment of adult hip flexion contracture due to neurological diseases; we have tried to outline an algorithm to choose the best treatment avoiding useless or too aggressive therapies. We present 5 cases of adult hips flexion due to neurological conditions treated following our algorithm. At 1-year-follow-up all patients had a good clinical outcome in terms of hip range of motion, pain and recovery of walking if possible. In conclusion we think that this algorithm could be a good guideline to treat these complex cases even if we need to treat more patients to confirm this theory. We believe also that postoperation physiotherapy it is useful in hip motility preservation, improvement of muscular function, and walking ability recovery when possible. PMID:24707293

  13. Adult Hip Flexion Contracture due to Neurological Disease: A New Treatment Protocol-Surgical Treatment of Neurological Hip Flexion Contracture.

    PubMed

    Nicodemo, Alberto; Arrigoni, Chiara; Bersano, Andrea; Massè, Alessandro

    2014-01-01

    Congenital, traumatic, or extrinsic causes can lead people to paraplegia; some of these are potentially; reversible and others are not. Paraplegia can couse hip flexion contracture and, consequently, pressure sores, scoliosis, and hyperlordosis; lumbar and groin pain are strictly correlated. Scientific literature contains many studies about children hip flexion related to neurological diseases, mainly caused by cerebral palsy; only few papers focus on this complication in adults. In this study we report our experience on surgical treatment of adult hip flexion contracture due to neurological diseases; we have tried to outline an algorithm to choose the best treatment avoiding useless or too aggressive therapies. We present 5 cases of adult hips flexion due to neurological conditions treated following our algorithm. At 1-year-follow-up all patients had a good clinical outcome in terms of hip range of motion, pain and recovery of walking if possible. In conclusion we think that this algorithm could be a good guideline to treat these complex cases even if we need to treat more patients to confirm this theory. We believe also that postoperation physiotherapy it is useful in hip motility preservation, improvement of muscular function, and walking ability recovery when possible.

  14. Extracorporeal shock wave treatment for chronic plantar fasciitis (heel pain).

    PubMed

    Ho, C

    2007-01-01

    (1) Electrohydraulic, electromagnetic, or piezoelectric devices are used to translate energy into acoustic waves during extracorporeal shock wave treatment (ESWT) for chronic plantar fasciitis (or heel pain). These waves may help to accelerate the healing process via an unknown mechanism. (2) ESWT, which is performed as an outpatient procedure, is intended to alleviate the pain due to chronic plantar fasciitis. (3) Results from randomized controlled trials have been conflicting. Six trials reported data that favour ESWT over placebo or conservative treatment for efficacy outcomes, while three trials showed no significant difference between the ESWT group and the placebo group. (4) The lack of convergent findings from randomized trials of ESWT for chronic plantar fasciitis suggests uncertainty about its effectiveness. The evidence reviewed in this bulletin does not support the use of this technology for this condition.

  15. Plantar Fasciitis: Will Physical Therapy Help My Foot Pain?

    PubMed

    2017-02-01

    One out of 10 people in the United States experience persistent pain along the bottom of the foot, a condition known as plantar fasciitis. In 2014, the Orthopaedic Section of the American Physical Therapy Association published updated clinical practice guidelines on the best treatments for patients with plantar fasciitis. The guidelines present evidence that strongly suggests a combination of manual therapy and rehabilitative exercises to help patients with this foot condition. In a more recent study published in the February 2017 issue of JOSPT, researchers reviewed the records of people with plantar fasciitis who were sent to physical therapy. The results of this study support prior studies that show faster recovery time for those who receive evidence-based physical therapy for their foot pain. J Orthop Sports Phys Ther 2017;47(2):56. doi:10.2519/jospt.2017.0501.

  16. Enthesopathy of the lateral cord of the plantar fascia.

    PubMed

    Hoffman, Douglas F; Nazarian, Levon N; Smith, Jay

    2014-09-01

    The objective of this study was to raise awareness of the diagnosis of enthesopathy of the lateral cord of the plantar fascia (LCPF) and describe its sonographic findings. We conducted a retrospective case series of 13 sonographic examinations with the diagnosis of LCPF enthesopathy. Two cadaver dissections of the plantar foot were performed for anatomic correlation. Sonographic findings of LCPF enthesopathy included generalized or focal hypoechoic thickening, loss of the normal fibrillar echo texture, cortical irregularity of the fifth metatarsal tuberosity, and vascularity on color Doppler imaging. Anatomic dissections of the plantar foot detailed the course of the LCPF and served as a guide for optimal sonographic imaging. Enthesopathy of the LCPF is an important etiology of nontraumatic pain at the base of the fifth metatarsal. Sonographic evaluation can readily show the characteristic findings of LCPF enthesopathy. © 2014 by the American Institute of Ultrasound in Medicine.

  17. Insertion torque, resonance frequency, and removal torque analysis of microimplants.

    PubMed

    Tseng, Yu-Chuan; Ting, Chun-Chan; Du, Je-Kang; Chen, Chun-Ming; Wu, Ju-Hui; Chen, Hong-Sen

    2016-09-01

    This study aimed to compare the insertion torque (IT), resonance frequency (RF), and removal torque (RT) among three microimplant brands. Thirty microimplants of the three brands were used as follows: Type A (titanium alloy, 1.5-mm × 8-mm), Type B (stainless steel, 1.5-mm × 8-mm), and Type C (titanium alloy, 1.5-mm × 9-mm). A synthetic bone with a 2-mm cortical bone and bone marrow was used. Each microimplant was inserted into the synthetic bone, without predrilling, to a 7 mm depth. The IT, RF, and RT were measured in both vertical and horizontal directions. One-way analysis of variance and Spearman's rank correlation coefficient tests were used for intergroup and intragroup comparisons, respectively. In the vertical test, the ITs of Type C (7.8 Ncm) and Type B (7.5 Ncm) were significantly higher than that of Type A (4.4 Ncm). The RFs of Type C (11.5 kHz) and Type A (10.2 kHz) were significantly higher than that of Type B (7.5 kHz). Type C (7.4 Ncm) and Type B (7.3 Ncm) had significantly higher RTs than did Type A (4.1 Ncm). In the horizontal test, both the ITs and RTs were significantly higher for Type C, compared with Type A. No significant differences were found among the groups, and the study hypothesis was accepted. Type A had the lowest inner/outer diameter ratio and widest apical facing angle, engendering the lowest IT and highest RF values. However, no significant correlations in the IT, RF, and RT were observed among the three groups. Copyright © 2016. Published by Elsevier Taiwan.

  18. Abnormal attachments between a plantar aponeurosis and calcaneus

    PubMed Central

    KALNIEV, MANOL ANASTASOV; KRASTEV, DIMO; KRASTEV, NIKOLAY; VIDINOV, KALIN; VELTCHEV, LUDMIL; MILEVA, MILKA

    2013-01-01

    Background and aims The plantar aponeurosis or fascia is a thick fascial seal located on the lower surface of the sole. It consists of three parts central, lateral, and medial. The central portion is the thickest. It is narrow behind and wider in front. The central portion has two strong vertical intermuscular septa which are directed upward into the foot. The lateral and medial portions are thinner. The medial portion is thinnest. The lateral portion is thin in front and thick behind. The main function of the plantar fascia is to support the longitudinal arch of the foot. In May 2013 during a routine dissection in the section hall of the Department of Anatomy and Histology in Medical University – Sofia, Bulgaria we came across a very interesting variation of the plantar aponeurosis. Materials and methods For the present morphological study tissues from a human corpse material were used. This unusual anatomical variation was photographed using a Nikon Coolpix 995 camera with a 3.34 Megapixels. Results We found some fibrous strands which started from the proximal portion of the plantar aponeurosis on the left foot. The fibrous strands resembled the tentacles of an octopus and started from the proximal portion of the aponeurosis. Two of fibrous strands were directed laterally to adipose tissue and one was directed medially and backward. The first lateral fibrous strand was divided into several fascicles. We found very few data in literature about the varieties of the plantar fascia. Conclusion It is very important to consider the occurrence of above mentioned variations in the plantar aponeurosis when surgical procedures are performed on the sole. PMID:26527947

  19. Effect of knee angle on neuromuscular assessment of plantar flexor muscles: A reliability study

    PubMed Central

    Cornu, Christophe; Jubeau, Marc

    2018-01-01

    Introduction This study aimed to determine the intra- and inter-session reliability of neuromuscular assessment of plantar flexor (PF) muscles at three knee angles. Methods Twelve young adults were tested for three knee angles (90°, 30° and 0°) and at three time points separated by 1 hour (intra-session) and 7 days (inter-session). Electrical (H reflex, M wave) and mechanical (evoked and maximal voluntary torque, activation level) parameters were measured on the PF muscles. Intraclass correlation coefficients (ICC) and coefficients of variation were calculated to determine intra- and inter-session reliability. Results The mechanical measurements presented excellent (ICC>0.75) intra- and inter-session reliabilities regardless of the knee angle considered. The reliability of electrical measurements was better for the 90° knee angle compared to the 0° and 30° angles. Conclusions Changes in the knee angle may influence the reliability of neuromuscular assessments, which indicates the importance of considering the knee angle to collect consistent outcomes on the PF muscles. PMID:29596480

  20. Foot mobility and plantar fascia elasticity in patients with plantar fasciitis.

    PubMed

    Sahin, Namık; Oztürk, Alpaslan; Atıcı, Teoman

    2010-01-01

    In this study, we investigated the radiologic changes of feet in sagittal plane under weightbearing either with or without plantar fasciitis. The study includes 64 feet of the 42 subjects with heel pain (Group 1: 32 women, 10 men, mean age 48 years, range 33-57 years) and 80 feet of the 40 patients (Group 2: 30 women, 10 men, mean age 47.2 years, range 35-56 years) without heel pain. Calcaneal inclination angle (CIA), calcaneal-first metatarsal angle (CMA), and plantar fascia length (PFL) were measured in the lateral radiographs of the weightbearing and non-weightbearing foot. The values of Group 1 and Group 2 were compared. The mean CIA was 26° (range 18-35°), CMA was 121° (range 115-133°), and PFL was 131 mm (range 110-158 mm) in non-weightbearing position for Group 1. The mean CIA was 27° (range 17-38°), CMA was 122° (range 110-135°), and PFL was 136 mm (range 120-155 mm) in non-weightbearing position for Group 2. The mean CIA was 13.6° (range 5-25°), CMA was 138° (range 130-153°), and PFU was 143.8 mm (range 118-158 mm) in weightbearing position for Group 1. The mean CIA was 9.9° (range 4-25°), CMA was 145° (range 130-155°), and PFU was 151.4 mm (range 137-167 mm) in weightbearing position for Group 2. The difference between CIA, CMA, and PFL values were -13°, 17°, and 12 mm under condition of weightbearing and nonweightbearing position values for Group 1; and -17°, 23°, and 15 mm for Group 2. The differences were significant between weightbearing and non-weightbearing position values (p<0.05). The reduced CIA, CMA, and PFL changes during weight bearing might show reduced foot mobility and plantar fascia elasticity, which may lead to posterior heel pain syndrome.

  1. Full Range of Motion Induces Greater Muscle Damage Than Partial Range of Motion in Elbow Flexion Exercise With Free Weights.

    PubMed

    Baroni, Bruno M; Pompermayer, Marcelo G; Cini, Anelize; Peruzzolo, Amanda S; Radaelli, Régis; Brusco, Clarissa M; Pinto, Ronei S

    2017-08-01

    Baroni, BM, Pompermayer, MG, Cini, A, Peruzzolo, AS, Radaelli, R, Brusco, CM, and Pinto, RS. Full range of motion induces greater muscle damage than partial range of motion in elbow flexion exercise with free weights. J Strength Cond Res 31(8): 2223-2230, 2017-Load and range of motion (ROM) applied in resistance training (RT) affect the muscle damage magnitude and the recovery time-course. Because exercises performed with partial ROM allow a higher load compared with those with full ROM, this study investigated the acute effect of a traditional RT exercise using full ROM or partial ROM on muscle damage markers. Fourteen healthy men performed 4 sets of 10 concentric-eccentric repetitions of unilateral elbow flexion on the Scott bench. Arms were randomly assigned to partial-ROM (50-100°) and full-ROM (0-130°) conditions, and load was determined as 80% of 1 repetition maximum (1RM) in the full- and partial-ROM tests. Muscle damage markers were assessed preexercise, immediately, and 24, 48, and 72 hours after exercise. Primary outcomes were peak torque, muscle soreness during palpation and elbow extension, arm circumference, and joint ROM. The load lifted in the partial-ROM condition (1RM = 19.1 ± 3.0 kg) was 40 ± 18% higher compared with the full-ROM condition (1RM = 13.7 ± 2.2 kg). Seventy-two hours after exercise, the full-ROM condition led to significant higher soreness sensation during elbow extension (1.3-4.1 cm vs. 1.0-1.9 cm) and smaller ROM values (97.5-106.1° vs. 103.6-115.7°). Peak torque, soreness from palpation, and arm circumference were statistically similar between conditions, although mean values in all time points of these outcomes have suggested more expressive muscle damage for the full-ROM condition. In conclusion, elbow flexion exercise with full ROM seems to induce greater muscle damage than partial-ROM exercises, even though higher absolute load was achieved with partial ROM.

  2. Management of Plantar Hyperhidrosis with Endoscopic Lumbar Sympathectomy.

    PubMed

    Rieger, Roman

    2016-11-01

    Primary plantar hyperhidrosis is defined as excessive secretion of the sweat glands of the feet and may lead to significant limitations in private and professional lifestyle and reduction of health-related quality of life. Conservative therapy measures usually fail to provide sufficient relieve of symptoms and do not allow long-lasting elimination of hyperhidrosis. Endoscopic lumbar sympathectomy appears to be a safe and effective procedure for eliminating excessive sweating of the feet and improves quality of life of patients with severe plantar hyperhidrosis. Copyright © 2016 Elsevier Inc. All rights reserved.

  3. 14 CFR 23.361 - Engine torque.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... Engine torque. (a) Each engine mount and its supporting structure must be designed for the effects of— (1... rational analysis, a factor of 1.6 must be used. (b) For turbine engine installations, the engine mounts... 14 Aeronautics and Space 1 2011-01-01 2011-01-01 false Engine torque. 23.361 Section 23.361...

  4. 14 CFR 25.361 - Engine torque.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... engine mount and its supporting structure must be designed for the effects of— (1) A limit engine torque.... (b) For turbine engine installations, the engine mounts and supporting structure must be designed to... 14 Aeronautics and Space 1 2010-01-01 2010-01-01 false Engine torque. 25.361 Section 25.361...

  5. 14 CFR 23.361 - Engine torque.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... Engine torque. (a) Each engine mount and its supporting structure must be designed for the effects of— (1... rational analysis, a factor of 1.6 must be used. (b) For turbine engine installations, the engine mounts... 14 Aeronautics and Space 1 2014-01-01 2014-01-01 false Engine torque. 23.361 Section 23.361...

  6. 14 CFR 23.361 - Engine torque.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... Engine torque. (a) Each engine mount and its supporting structure must be designed for the effects of— (1... rational analysis, a factor of 1.6 must be used. (b) For turbine engine installations, the engine mounts... 14 Aeronautics and Space 1 2013-01-01 2013-01-01 false Engine torque. 23.361 Section 23.361...

  7. 14 CFR 25.361 - Engine torque.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... engine mount and its supporting structure must be designed for the effects of— (1) A limit engine torque.... (b) For turbine engine installations, the engine mounts and supporting structure must be designed to... 14 Aeronautics and Space 1 2012-01-01 2012-01-01 false Engine torque. 25.361 Section 25.361...

  8. 14 CFR 25.361 - Engine torque.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... engine mount and its supporting structure must be designed for the effects of— (1) A limit engine torque.... (b) For turbine engine installations, the engine mounts and supporting structure must be designed to... 14 Aeronautics and Space 1 2014-01-01 2014-01-01 false Engine torque. 25.361 Section 25.361...

  9. 14 CFR 23.361 - Engine torque.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... Engine torque. (a) Each engine mount and its supporting structure must be designed for the effects of— (1... rational analysis, a factor of 1.6 must be used. (b) For turbine engine installations, the engine mounts... 14 Aeronautics and Space 1 2012-01-01 2012-01-01 false Engine torque. 23.361 Section 23.361...

  10. 14 CFR 23.361 - Engine torque.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... Engine torque. (a) Each engine mount and its supporting structure must be designed for the effects of— (1... rational analysis, a factor of 1.6 must be used. (b) For turbine engine installations, the engine mounts... 14 Aeronautics and Space 1 2010-01-01 2010-01-01 false Engine torque. 23.361 Section 23.361...

  11. 14 CFR 25.361 - Engine torque.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... engine mount and its supporting structure must be designed for the effects of— (1) A limit engine torque.... (b) For turbine engine installations, the engine mounts and supporting structure must be designed to... 14 Aeronautics and Space 1 2011-01-01 2011-01-01 false Engine torque. 25.361 Section 25.361...

  12. 14 CFR 25.361 - Engine torque.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... engine mount and its supporting structure must be designed for the effects of— (1) A limit engine torque.... (b) For turbine engine installations, the engine mounts and supporting structure must be designed to... 14 Aeronautics and Space 1 2013-01-01 2013-01-01 false Engine torque. 25.361 Section 25.361...

  13. Radiation Forces and Torques without Stress (Tensors)

    ERIC Educational Resources Information Center

    Bohren, Craig F.

    2011-01-01

    To understand radiation forces and torques or to calculate them does not require invoking photon or electromagnetic field momentum transfer or stress tensors. According to continuum electromagnetic theory, forces and torques exerted by radiation are a consequence of electric and magnetic fields acting on charges and currents that the fields induce…

  14. Displaying Force and Torque of A Manipulator

    NASA Technical Reports Server (NTRS)

    Bejczy, A. K.; Dotson, R. S.; Primus, H. C.

    1984-01-01

    Display combines bar charts, vector diagrams, and numerical values to inform operator of forces and torques exerted by end effector of manipulator. On voice or keyboard command, eight-channel strip-chart recorder traces force and torque components and claw position of raw measurements from eight strain gage sensors in end effector. Especially helpful when operator's view of end effector is obscured.

  15. Active motion assisted by correlated stochastic torques.

    PubMed

    Weber, Christian; Radtke, Paul K; Schimansky-Geier, Lutz; Hänggi, Peter

    2011-07-01

    The stochastic dynamics of an active particle undergoing a constant speed and additionally driven by an overall fluctuating torque is investigated. The random torque forces are expressed by a stochastic differential equation for the angular dynamics of the particle determining the orientation of motion. In addition to a constant torque, the particle is supplemented by random torques, which are modeled as an Ornstein-Uhlenbeck process with given correlation time τ(c). These nonvanishing correlations cause a persistence of the particles' trajectories and a change of the effective spatial diffusion coefficient. We discuss the mean square displacement as a function of the correlation time and the noise intensity and detect a nonmonotonic dependence of the effective diffusion coefficient with respect to both correlation time and noise strength. A maximal diffusion behavior is obtained if the correlated angular noise straightens the curved trajectories, interrupted by small pirouettes, whereby the correlated noise amplifies a straightening of the curved trajectories caused by the constant torque.

  16. Torque Measurement at the Single Molecule Level

    PubMed Central

    Forth, Scott; Sheinin, Maxim Y.; Inman, James; Wang, Michelle D.

    2017-01-01

    Methods for exerting and measuring forces on single molecules have revolutionized the study of the physics of biology. However, it is often the case that biological processes involve rotation or torque generation, and these parameters have been more difficult to access experimentally. Recent advances in the single molecule field have led to the development of techniques which add the capability of torque measurement. By combining force, displacement, torque, and rotational data, a more comprehensive description of the mechanics of a biomolecule can be achieved. In this review, we highlight a number of biological processes for which torque plays a key mechanical role. We describe the various techniques that have been developed to directly probe the torque experienced by a single molecule, and detail a variety of measurements made to date using these new technologies. We conclude by discussing a number of open questions and propose systems of study which would be well suited for analysis with torsional measurement techniques. PMID:23541162

  17. Calibration of the optical torque wrench.

    PubMed

    Pedaci, Francesco; Huang, Zhuangxiong; van Oene, Maarten; Dekker, Nynke H

    2012-02-13

    The optical torque wrench is a laser trapping technique that expands the capability of standard optical tweezers to torque manipulation and measurement, using the laser linear polarization to orient tailored microscopic birefringent particles. The ability to measure torque of the order of kBT (∼4 pN nm) is especially important in the study of biophysical systems at the molecular and cellular level. Quantitative torque measurements rely on an accurate calibration of the instrument. Here we describe and implement a set of calibration approaches for the optical torque wrench, including methods that have direct analogs in linear optical tweezers as well as introducing others that are specifically developed for the angular variables. We compare the different methods, analyze their differences, and make recommendations regarding their implementations.

  18. Estimating Torque Imparted on Spacecraft Using Telemetry

    NASA Technical Reports Server (NTRS)

    Lee, Allan Y.; Wang, Eric K.; Macala, Glenn A.

    2013-01-01

    There have been a number of missions with spacecraft flying by planetary moons with atmospheres; there will be future missions with similar flybys. When a spacecraft such as Cassini flies by a moon with an atmosphere, the spacecraft will experience an atmospheric torque. This torque could be used to determine the density of the atmosphere. This is because the relation between the atmospheric torque vector and the atmosphere density could be established analytically using the mass properties of the spacecraft, known drag coefficient of objects in free-molecular flow, and the spacecraft velocity relative to the moon. The density estimated in this way could be used to check results measured by science instruments. Since the proposed methodology could estimate disturbance torque as small as 0.02 N-m, it could also be used to estimate disturbance torque imparted on the spacecraft during high-altitude flybys.

  19. In-line rotating capacitive torque sensor

    DOEpatents

    Kronberg, J.W.

    1991-09-10

    Disclosed are a method and apparatus for measuring torques developed along a rotating mechanical assembly comprising a rotating inner portion and a stationary outer portion. The rotating portion has an electrically-conductive flexing section fitted between two coaxial shafts in a configuration which varies radially in accordance with applied torque. The stationary portion comprises a plurality of conductive plates forming a surface concentric with and having a diameter slightly larger than the diameter of the rotating portion. The capacitance between the outer, nonrotating and inner, rotating portion varies with changes in the radial configuration of the rotating portion. Signal output varies approximately linearly with torque for small torques, nonlinearly for larger torques. The sensor is preferably surrounded by a conductive shell to minimize electrical interference from external sources. 18 figures.

  20. In-line rotating capacitive torque sensor

    DOEpatents

    Kronberg, James W.

    1991-01-01

    A method and apparatus for measuring torques developed along a rotating mechanical assembly comprising a rotating inner portion and a stationary outer portion. The rotating portion has an electrically-conductive flexing section fitted between two coaxial shafts in a configuration which varies radially in accordance with applied torque. The stationary portion comprises a plurality of conductive plates forming a surface concentric with and having a diameter slightly larger than the diameter of the rotating portion. The capacitance between the outer, nonrotating and inner, rotating portion varies with changes in the radial configuration of the rotating portion. Signal output varies approximately linearly with torque for small torques, nonlinearly for larger torques. The sensor is preferably surrounded by a conductive shell to minimize electrical interference from external sources.

  1. Electromagnetic torque tweezers: a versatile approach for measurement of single-molecule twist and torque.

    PubMed

    Janssen, Xander J A; Lipfert, Jan; Jager, Tessa; Daudey, Renier; Beekman, Jaap; Dekker, Nynke H

    2012-07-11

    The well-established single-molecule force-spectroscopy techniques have recently been complemented by methods that can measure torque and twist directly, notably magnetic torque tweezers and the optical torque wrench. A limitation of the current torque measurement schemes is the intrinsic coupling between the force and torque degrees of freedom. Here we present electromagnetic torque tweezers (eMTT) that combine permanent and electromagnets to enable independent control of the force and torsional trap stiffness for sensitive measurements of single molecule torque and twist. Using the eMTT, we demonstrate sensitive torque measurements on tethered DNA molecules from simple tracking of the beads' (x,y)-position, obviating the need for any angular tracking algorithms or markers. Employing the eMTT for high-resolution torque measurements, we experimentally confirm the theoretically predicted torque overshoot at the DNA buckling transition in high salt conditions. We envision that the flexibility and control afforded by the eMTT will enable a range of new torque and twist measurement schemes from single-molecules to living cells.

  2. A magneto-rheological fluid-based torque sensor for smart torque wrench application

    NASA Astrophysics Data System (ADS)

    Ahmadkhanlou, Farzad; Washington, Gregory N.

    2013-04-01

    In this paper, the authors have developed a new application where MR fluid is being used as a sensor. An MR-fluid based torque wrench has been developed with a rotary MR fluid-based damper. The desired set torque ranges from 1 to 6 N.m. Having continuously controllable yield strength, the MR fluid-based torque wrench presents a great advantage over the regular available torque wrenches in the market. This design is capable of providing continuous set toque from the lower limit to the upper limit while regular torque wrenches provide discrete set torques only at some limited points. This feature will be especially important in high fidelity systems where tightening torque is very critical and the tolerances are low.

  3. Plantar fascia-specific stretching versus radial shock-wave therapy as initial treatment of plantar fasciopathy.

    PubMed

    Rompe, Jan D; Cacchio, Angelo; Weil, Lowell; Furia, John P; Haist, Joachim; Reiners, Volker; Schmitz, Christoph; Maffulli, Nicola

    2010-11-03

    Whether plantar fascia-specific stretching or shock-wave therapy is effective as an initial treatment for proximal plantar fasciopathy remains unclear. The aim of this study was to test the null hypothesis of no difference in the effectiveness of these two forms of treatment for patients who had unilateral plantar fasciopathy for a maximum duration of six weeks and which had not been treated previously. One hundred and two patients with acute plantar fasciopathy were randomly assigned to perform an eight-week plantar fascia-specific stretching program (Group I, n = 54) or to receive repetitive low-energy radial shock-wave therapy without local anesthesia, administered weekly for three weeks (Group II, n = 48). All patients completed the seven-item pain subscale of the validated Foot Function Index and a patient-relevant outcome questionnaire. Patients were evaluated at baseline and at two, four, and fifteen months after baseline. The primary outcome measures were a mean change in the Foot Function Index sum score at two months after baseline, a mean change in item 2 (pain during the first few steps of walking in the morning) on this index, and satisfaction with treatment. No difference in mean age, sex, weight, or duration of symptoms was found between the groups at baseline. At two months after baseline, the Foot Function Index sum score showed significantly greater changes for the patients managed with plantar fascia-specific stretching than for those managed with shock-wave therapy (p < 0.001), as well as individually for item 2 (p = 0.002). Thirty-five patients (65%) in Group I versus fourteen patients (29%) in Group II were satisfied with the treatment (p < 0.001). These findings persisted at four months. At fifteen months after baseline, no significant between-group difference was measured. A program of manual stretching exercises specific to the plantar fascia is superior to repetitive low-energy radial shock-wave therapy for the treatment of acute symptoms

  4. Do changes in neuromuscular activation contribute to the knee extensor angle-torque relationship?

    PubMed

    Lanza, Marcel B; Balshaw, Thomas G; Folland, Jonathan P

    2017-08-01

    What is the central question of the study? Do changes in neuromuscular activation contribute to the knee extensor angle-torque relationship? What is the main finding and its importance? Both agonist (quadriceps) and antagonist coactivation (hamstrings) differed with knee joint angle during maximal isometric knee extensions and thus both are likely to contribute to the angle-torque relationship. Specifically, two independent measurement techniques showed quadriceps activation to be lower at more extended positions. These effects might influence the capacity for neural changes in response to training and rehabilitation at different knee joint angles. The influence of joint angle on knee extensor neuromuscular activation is unclear, owing in part to the diversity of surface electromyography (sEMG) and/or interpolated twitch technique (ITT) methods used. The aim of the study was to compare neuromuscular activation, using rigorous contemporary sEMG and ITT procedures, during isometric maximal voluntary contractions (iMVCs) of the quadriceps femoris at different knee joint angles and examine whether activation contributes to the angle-torque relationship. Sixteen healthy active men completed two familiarization sessions and two experimental sessions of isometric knee extension and knee flexion contractions. The experimental sessions included the following at each of four joint angles (25, 50, 80 and 106 deg): iMVCs (with and without superimposed evoked doublets); submaximal contractions with superimposed doublets; and evoked twitch and doublet contractions whilst voluntarily passive, and knee flexion iMVC at the same knee joint positions. The absolute quadriceps femoris EMG was normalized to the peak-to-peak amplitude of an evoked maximal M-wave, and the doublet-voluntary torque relationship was used to calculate activation with the ITT. Agonist activation, assessed with both normalized EMG and the ITT, was reduced at the more extended compared with the more flexed

  5. Retroperitoneoscopic lumbar sympathectomy for plantar hyperhidrosis.

    PubMed

    Lima, Sonia O; de Santana, Vanessa R; Valido, Daisy P; de Andrade, Renata L B; Fontes, Leticia M; Leite, Victor Hugo O; Neto, José M; Santos, Jéssica M; Varjão, Lucas L; Reis, Francisco P

    2017-12-01

    The objective of this study was to assess the reduction in quality of life (QoL) caused by the persistence of primary plantar hyperhidrosis (PPH) symptoms and the level of satisfaction in PPH patients after retroperitoneoscopic lumbar sympathectomy (RLS). The efficacy, safety, and procedure of bilateral RLS in both sexes are also described in this study. This is a longitudinal study of consecutive patients who sought specific treatment from a private practitioner for severe PPH as classified on the Hyperhidrosis Disease Severity Scale (HDSS) from October 2005 to October 2014. The patients were asked to report the symptoms of PPH experienced in the immediate preoperative period and to complete a standardized QoL questionnaire developed by de Campos at least 12 months after RLS. Disease outcomes, recurrence of symptoms, and any adverse effects of surgery were evaluated after 30 days and at least 12 months after RLS. Lumbar sympathectomy was performed 116 times in 58 patients; 30 days after surgery, PPH was resolved in all patients. Three patients (5.2%) reported transient thigh neuralgia, and 19 (32.7%) reported transient paresthesia in the lower limbs. There were no reports of retrograde ejaculation. At a minimum of 12 months after RLS, 49 of the 58 patients had fully and correctly answered the follow-up questionnaire and noted a mild (HDSS 2) to moderate (HDSS 3) increase in pre-existing compensatory sweating. One patient had a PPH relapse within 6 months. Improvement in QoL due to the resolution of PPH was reported in 98% of the 49 patients. None of the operations necessitated a change in the laparotomy approach, and none of the patients died. RLS is safe and effective for the treatment of severe PPH in both sexes. There were no reports of retrograde ejaculation after resection of L3 and L4 ganglia. There was a mild to moderate increase in compensatory sweating in about half of the patients, but without any regret or dissatisfaction for having undergone the

  6. Relationship Between Force Production During Isometric Squats and Knee Flexion Angles During Landing.

    PubMed

    Fisher, Harry; Stephenson, Mitchell L; Graves, Kyle K; Hinshaw, Taylour J; Smith, Derek T; Zhu, Qin; Wilson, Margaret A; Dai, Boyi

    2016-06-01

    Decreased knee flexion angles during landing are associated with increased anterior cruciate ligament loading. The underlying mechanisms associated with decreased self-selected knee flexion angles during landing are still unclear. The purpose of this study was to establish the relationship between the peak force production at various knee flexion angles (35, 55, 70, and 90°) during isometric squats and the actual knee flexion angles that occur during landing in both men and women. A total of 18 men and 18 women recreational/collegiate athletes performed 4 isometric squats at various knee flexion angles while vertical ground reaction forces were recorded. Participants also performed a jump-landing-jump task while lower extremity kinematics were collected. For women, significant correlations were found between the peak force production at 55 and 70° of knee flexion during isometric squats and the knee flexion angle at initial contact of landing. There were also significant correlations between the peak force production at 55, 70, and 90° of knee flexion during isometric squats and the peak knee flexion angle during landing. These correlations tended to be stronger during isometric squats at greater knee flexion compared with smaller knee flexion. No significant correlations were found for men. Posture-specific strength may play an important role in determining self-selected knee flexion angles during landing for women.

  7. Lumbopelvic flexibility modulates neuromuscular responses during trunk flexion-extension.

    PubMed

    Sánchez-Zuriaga, Daniel; Artacho-Pérez, Carla; Biviá-Roig, Gemma

    2016-06-01

    Various stimuli such as the flexibility of lumbopelvic structures influence the neuromuscular responses of the trunk musculature, leading to different load sharing strategies and reflex muscle responses from the afferents of lumbopelvic mechanoreceptors. This link between flexibility and neuromuscular response has been poorly studied. The aim of this study was to investigate the relationship between lumbopelvic flexibility and neuromuscular responses of the erector spinae, hamstring and abdominal muscles during trunk flexion-extension. Lumbopelvic movement patterns were measured in 29 healthy women, who were separated into two groups according to their flexibility during trunk flexion-extension. The electromyographic responses of erector spinae, rectus abdominis and biceps femoris were also recorded. Subjects with greater lumbar flexibility had significantly less pelvic flexibility and vice versa. Subjects with greater pelvic flexibility had a higher rate of relaxation and lower levels of hamstring activation during maximal trunk flexion. The neuromuscular response patterns of the hamstrings seem partially modulated by pelvic flexibility. Not so with the lumbar erector spinae and lumbar flexibility, despite the assertions of some previous studies. The results of this study improve our knowledge of the relationships between trunk joint flexibility and neuromuscular responses, a relationship which may play a role in low back pain. Copyright © 2016 Elsevier Ltd. All rights reserved.

  8. Patellofemoral joint contact forces during activities with high knee flexion.

    PubMed

    Trepczynski, Adam; Kutzner, Ines; Kornaropoulos, Evgenios; Taylor, William R; Duda, Georg N; Bergmann, Georg; Heller, Markus O

    2012-03-01

    The patellofemoral (PF) joint plays an essential role in knee function, but little is known about the in vivo loading conditions at the joint. We hypothesized that the forces at the PF joint exceed the tibiofemoral (TF) forces during activities with high knee flexion. Motion analysis was performed in two patients with telemetric knee implants during walking, stair climbing, sit-to-stand, and squat. TF and PF forces were calculated using a musculoskeletal model, which was validated against the simultaneously measured in vivo TF forces, with mean errors of 10% and 21% for the two subjects. The in vivo peak TF forces of 2.9-3.4 bodyweight (BW) varied little across activities, while the peak PF forces showed significant variability, ranging from less than 1 BW during walking to more than 3 BW during high flexion activities, exceeding the TF forces. Together with previous in vivo measurements at the hip and knee, the PF forces determined here provide evidence that peak forces across these joints reach values of around 3 BW during high flexion activities, also suggesting that the in vivo loading conditions at the knee can only be fully understood if the forces at the TF and the PF joints are considered together. Copyright © 2011 Orthopaedic Research Society.

  9. In-vivo spinal cord deformation in flexion

    NASA Astrophysics Data System (ADS)

    Yuan, Qing; Dougherty, Lawrence; Margulies, Susan S.

    1997-05-01

    Traumatic mechanical loading of the head-neck complex results cervical spinal cord injury when the distortion of the cord is sufficient to produce functional or structural failure of the cord's neural and/or vascular components. Characterizing cervical spinal cord deformation during physiological loading conditions is an important step to defining a comprehensive injury threshold associated with acute spinal cord injury. In this study, in vivo quasi- static deformation of the cervical spinal cord during flexion of the neck in human volunteers was measured using magnetic resonance (MR) imaging of motion with spatial modulation of magnetization (SPAMM). A custom-designed device was built to guide the motion of the neck and enhance more reproducibility. the SPAMM pulse sequence labeled the tissue with a series of parallel tagging lines. A single- shot gradient-recalled-echo sequence was used to acquire the mid-sagittal image of the cervical spine. A comparison of the tagged line pattern in each MR reference and deformed image pair revealed the distortion of the spinal cord. The results showed the cervical spinal cord elongates during head flexion. The elongation experienced by the spinal cord varies linearly with head flexion, with the posterior surface of the cord stretching more than the anterior surface. The maximal elongation of the cord is about 12 percent of its original length.

  10. Early experience with endoscopic lumbar sympathectomy for plantar hyperhidrosis.

    PubMed

    Singh, Sanjay; Kaur, Simranjit; Wilson, Paul

    2016-05-01

    We describe our endoscopic lumbar sympathectomy technique and our early experience using it to treat plantar hyperhidrosis. We reviewed 20 lumbar sympathectomies performed in our vascular unit for plantar hyperhidrosis in 10 patients from 2011 and 2014. Demographics and outcomes were analyzed and a review of the literature conducted. All procedures were carried out endoscopically with no intraoperative or postoperative morbidity. Plantar anhidrosis was achieved in all the patients, although two patients (20%) suffered a relapse. Unwanted side-effects occurred in the form of compensatory sweating in three patients (30%) and post-sympathectomy neuralgia in two patients (20%). None of the patients experienced sexual dysfunction. Management of plantar hyperhidrosis may be based upon a therapeutic ladder starting with conservative measures and working up to surgery depending on the severity of the disease. Minimally invasive (endoscopic) sympathectomy for the thoracic chain is well established, but minimally invasive sympathectomy for the lumbar chain is a relatively new technique. Endoscopic lumbar sympathectomy provides an effective, minimally invasive method of surgical management, but long-term data are lacking. © 2016 Japan Society for Endoscopic Surgery, Asia Endosurgery Task Force and John Wiley & Sons Australia, Ltd.

  11. POFBG-Embedded Cork Insole for Plantar Pressure Monitoring

    PubMed Central

    Vilarinho, Débora; Theodosiou, Antreas; Domingues, Maria de Fátima; André, Paulo; Marques, Carlos

    2017-01-01

    We propose a novel polymer optical fiber (POF) sensing system based on fiber Bragg gratings (FBGs) to measure foot plantar pressure. The plantar pressure signals are detected by five FBGs, in the same piece of cyclic transparent optical polymer (CYTOP) fiber, which are embedded in a cork insole for the dynamic monitoring of gait. The calibration and measurements performed with the suggested system are presented, and the results obtained demonstrate the accuracy and reliability of the sensing platform to monitor the foot plantar pressure distribution during gait motion and the application of pressure. This architecture does not compromise the patient’s mobility nor interfere in their daily activities. The results using the CYTOP fiber showed a very good response when compared with solutions using silica optical fibers, resulting in a sensitivity almost twice as high, with excellent repeatability and ease of handling. The advantages of POF (e.g., high flexibility and robustness) proved that this is a viable solution for this type of application, since POF’s high fracture toughness enables its application in monitoring patients with higher body mass compared with similar systems based on silica fiber. This study has demonstrated the viability of the proposed system based on POF technology as a useful alternative for plantar pressure detection systems. PMID:29258166

  12. POFBG-Embedded Cork Insole for Plantar Pressure Monitoring.

    PubMed

    Vilarinho, Débora; Theodosiou, Antreas; Leitão, Cátia; Leal-Junior, Arnaldo G; Domingues, Maria de Fátima; Kalli, Kyriacos; André, Paulo; Antunes, Paulo; Marques, Carlos

    2017-12-16

    We propose a novel polymer optical fiber (POF) sensing system based on fiber Bragg gratings (FBGs) to measure foot plantar pressure. The plantar pressure signals are detected by five FBGs, in the same piece of cyclic transparent optical polymer (CYTOP) fiber, which are embedded in a cork insole for the dynamic monitoring of gait. The calibration and measurements performed with the suggested system are presented, and the results obtained demonstrate the accuracy and reliability of the sensing platform to monitor the foot plantar pressure distribution during gait motion and the application of pressure. This architecture does not compromise the patient's mobility nor interfere in their daily activities. The results using the CYTOP fiber showed a very good response when compared with solutions using silica optical fibers, resulting in a sensitivity almost twice as high, with excellent repeatability and ease of handling. The advantages of POF (e.g., high flexibility and robustness) proved that this is a viable solution for this type of application, since POF's high fracture toughness enables its application in monitoring patients with higher body mass compared with similar systems based on silica fiber. This study has demonstrated the viability of the proposed system based on POF technology as a useful alternative for plantar pressure detection systems.

  13. [Analysis of plantar pressure patterns among obese population].

    PubMed

    Leidecker, Eleonóra; Kellermann, Péter; Galambosné Tiszberger, Mónika; Molics, Bálint; Bohner-Beke, Aliz; Nyárády, József; Kránicz, János

    2016-11-01

    Although the role of body weight on foot health and load has been widely documented in research, the effect of the extra load due to body weight on plantar pressure characteristics is not well known. The aim of this study was to evaluate the impact of obesity on plantar pressure patterns among the working-age population. 180 participants were involved. Two groups were evaluated according to body mass index categories regarding eight regions of the plantar area, focusing on the following parameters: contact area, maximum pressure and peak pressure. Compared with non-obese subjects, the peak pressure was the highest on the midfoot (p<0.001) and the forefoot (p<0.001). Regarding the maximum force, significant statistical difference was detected on the toes (p<0.001), with a value lower among the obese group. The contact area on the total foot and the midfoot was lower among the non-obese subjects (p<0.001). Loading is greatly increasing on the whole plantar area, especially at the midfoot and the forefoot region. Orv. Hetil., 2016, 157(48), 1919-1925.

  14. Nordic Walking Practice Might Improve Plantar Pressure Distribution

    ERIC Educational Resources Information Center

    Perez-Soriano, Pedro; Llana-Belloch, Salvador; Martinez-Nova, Alfonso; Morey-Klapsing, G.; Encarnacion-Martinez, Alberto

    2011-01-01

    Nordic walking (NW), characterized by the use of two walking poles, is becoming increasingly popular (Morgulec-Adamowicz, Marszalek, & Jagustyn, 2011). We studied walking pressure patterns of 20 experienced and 30 beginner Nordic walkers. Plantar pressures from nine foot zones were measured during trials performed at two walking speeds (preferred…

  15. How We Manage Plantar Fasciitis (With Memory Jogger).

    ERIC Educational Resources Information Center

    Tanner, Suzanne M.; Harvey, Jack S.

    1988-01-01

    Common among runners and athletes who participate in jumping sports, plantar fasciitis is an overuse injury that is potentially incapacitating, causes heel and arch pain, and usually occurs after sudden increases in running mileage, frequency, or speed. Therapy is described. (Author/CB)

  16. Sonographic evaluation of the plantar fascia in asymptomatic subjects.

    PubMed

    Gadalla, N; Kichouh, M; Boulet, C; Machiels, F; De Mey, J; De Maeseneer, M

    2014-01-01

    To evaluate the appearance of the plantar fascia in asymptomatic subjects. Thirty-one asymptomatic subjects were examined by 2 musculoskeletal radiologists. The plantar fascia was evaluated for thickness, echogenicity, vascularity on power Doppler, rupture, fluid adjacent to the fascia, andcalcifications. The study included 14 men and 17 women (age, 17-79 years; mean, 45 years). The mean thickness of the plantar fascia in men was 3.7 mm (range 2.5-7 mm), and in women 3.5 mm (range, 1.7-5.1 mm). The thickness was greater than 4 mm in 4 men (bilateral in 2). The mean thickness of fascias thicker than 4 mm in men was 5.4 mm (range, 4.3-7 mm). The thickness was greater than 4 mm in 5 women ( bilateral in 4). The mean thickness of fascias thicker than 4 mm in women was 4.7 mm (range, 4.2-5.1 mm). There was no statistically significant difference between men and women and between both heels. Hypoechogenicity was observed in 3 men (bilateral in 2), and in 5 women (bilateral in 6). Hypervascularity, rupture, fluid adjacent to the fascia, and calcifications were not observed. A thickness greater than 4 mm and hypoechogenicity, are common in the plantar fascia of asymptomatic subjects. Findings that were not seen in asymptomatic subjects include a thickness greater than 7 mm, hypervascularity on power Doppler, rupture, fluid adjacent to the fascia, and calcifications.

  17. Modified uniportal endoscopic plantar fasciotomy: a technical report.

    PubMed

    Angthong, Chayanin; Charoenthamruksa, Chatchavan; Chumchuen, Sukanis; Kanitnate, Supakit; Khadsongkram, Anuwat; Angthong, Wirana

    2012-10-01

    Several authors have reported the benefits of the recent procedure of the dual portal endoscopic plantar fasciotomy (EPF). However, very little is known concerning its potential capability via the single portal EPF without special cutting device. The present study aimed to demonstrate the effectiveness of uniportal EPF in a patient with severe intractable plantar fasciitis following a failure of several conservative treatments. The recent technique; uniportal EPF under modified method, without a special cutting device, was reviewed in an effort to improve its capability for plantar release and to provide information for the avoidance of this procedure's complications. A patient, with the recalcitrant conditions and the progression of the severe plantar fasciitis of bilateral feet after a failure of the conservative treatments for 13-month period, was included in this report. All data of the preoperative and each successive postoperative period (1, 6 months and last follow-up) were prospectively collected including American Orthopedic Foot and Ankle Society (AOFAS) score, Visual Analogue Scale-Foot and Ankle (VAS-FA) score and any related complications. The operations were carried out by a single surgeon with the modified uniportal EPF via a simple hooked soft-tissue blade, without a special cutting device, on both feet simultaneously. All feet had uniportal EPF with transection of the medial 50% of the plantar fascia. Postoperatively, a patient was instructed to have partial-weight bearing for the first 2 weeks with wearing of full-length silicone insoles. Then, she is allowed to start to fully weightbear with the insoles. She is advised to cautiously return to daily activities and works at 2nd week after the operation. In regard to the EPF in two feet, there were clearly improvements in the comparison between preoperative and last follow-up period in terms of the increasing AOFAS scores, and VAS-FA scores. There were no significant iatrogenic-related complications

  18. Does high knee flexion cause separation of meniscal repairs?

    PubMed

    Lin, David L; Ruh, Sarah S; Jones, Hugh L; Karim, Azim; Noble, Philip C; McCulloch, Patrick C

    2013-09-01

    Previous clinical studies comparing nonrestrictive and restrictive protocols after meniscal repair have shown no difference in outcomes; however, some surgeons still limit range of motion out of concern that it will place undue stress on the repair. Large acute medial meniscal tears will gap during simulated open chain exercises at high flexion angles, and a repaired construct with vertical mattress sutures will not gap. Controlled laboratory study. Tantalum beads were implanted in the medial menisci of 6 fresh-frozen cadaveric knees via an open posteromedial approach. Each knee underwent 10 simulated open chain flexion cycles with loading of the quadriceps and hamstrings. Testing was performed on 3 different states of the meniscus: intact, torn, and repaired. Biplanar radiographs were taken of the loaded knee in 90°, 110°, and 135° of flexion for each state. A 2.5-cm tear was created in the posteromedial meniscus and repaired with inside-out vertical mattress sutures. Displacement of pairs of beads spanning the tear was measured in all planes by use of radiostereometric analysis (RSA) with an accuracy of better than 80 μm. With a longitudinal tear, compression rather than gapping occurred in all 3 regions of the posterior horn of the meniscus (mean ± standard deviation for medial collateral ligament [MCL], -321 ± 320 μm; midposterior, -487 ± 256 μm; root, -318 ± 150 μm) with knee flexion. After repair, meniscal displacement returned part way to intact values in both the MCL (+55 ± 250 μm) and root region (-170 ± 123 μm) but not the midposterior region, where further compression was seen (-661 ± 278 μm). Acute posteromedial meniscal tears and repairs with vertical mattress sutures do not gap, but rather compress in the transverse plane at higher flexion angles when subjected to physiologic loads consistent with active, open kinetic chain range of motion rehabilitation exercises. The kinematics of the repaired meniscus more closely resemble that of

  19. Forearm Torque and Lifting Strength: Normative Data.

    PubMed

    Axelsson, Peter; Fredrikson, Per; Nilsson, Anders; Andersson, Jonny K; Kärrholm, Johan

    2018-02-10

    To establish reference values for new methods designed to quantitatively measure forearm torque and lifting strength and to compare these values with grip strength. A total of 499 volunteers, 262 males and 237 females, aged 15 to 85 (mean, 44) years, were tested for lifting strength and forearm torque with the Kern and Baseline dynamometers. These individuals were also tested for grip strength with a Jamar dynamometer. Standardized procedures were used and information about sex, height, weight, hand dominance, and whether their work involved high or low manual strain was collected. Men had approximately 70% higher forearm torque and lifting strength compared with females. Male subjects aged 26 to 35 years and female subjects aged 36 to 45 years showed highest strength values. In patients with dominant right side, 61% to 78% had a higher or equal strength on this side in the different tests performed. In patients with dominant left side, the corresponding proportions varied between 41% and 65%. There was a high correlation between grip strength and forearm torque and lifting strength. Sex, body height, body weight, and age showed a significant correlation to the strength measurements. In a multiple regression model sex, age (entered as linear and squared) could explain 51% to 63% of the total variances of forearm torque strength and 30% to 36% of lifting strength. Reference values for lifting strength and forearm torque to be used in clinical practice were acquired. Grip strength has a high correlation to forearm torque and lifting strength. Sex, age, and height can be used to predict forearm torque and lifting strength. Prediction equations using these variables were generated. Normative data of forearm torque and lifting strength might improve the quality of assessment of wrist and forearm disorders as well as their treatments. Copyright © 2018 American Society for Surgery of the Hand. Published by Elsevier Inc. All rights reserved.

  20. The relationship between plantar pressure and footprint shape.

    PubMed

    Hatala, Kevin G; Dingwall, Heather L; Wunderlich, Roshna E; Richmond, Brian G

    2013-07-01

    Fossil footprints preserve the only direct evidence of the external foot morphologies and gaits of extinct hominin taxa. However, their interpretation requires an understanding of the complex interaction among foot anatomy, foot function, and soft sediment mechanics. We applied an experimental approach aimed at understanding how one measure of foot function, the distribution of plantar pressure, influences footprint topography. Thirty-eight habitually unshod and minimally shod Daasanach individuals (19 male, 19 female) walked across a pressure pad and produced footprints in sediment directly excavated from the geological layer that preserves 1.5 Ma fossil footprints at Ileret, Kenya. Calibrated pressure data were collected and three-dimensional models of all footprints were produced using photogrammetry. We found significant correlations (Spearman's rank, p < 0.0001) between measurements of plantar pressure distribution and relative footprint depths at ten anatomical regions across the foot. Furthermore, plantar pressure distributions followed a pattern similar to footprint topography, with areas of higher pressure tending to leave deeper impressions. This differs from the results of experimental studies performed in different types of sediment, supporting the hypothesis that sediment type influences the relationship between plantar pressure and footprint topography. Our results also lend support to previous interpretations that the shapes of the Ileret footprints preserve evidence of a medial transfer of plantar pressure during late stance phase, as seen in modern humans. However, the weakness of the correlations indicates that much of the variation in relative depths within footprints is not explained by pressure distributions under the foot when walking on firm ground, using the methods applied here. This warrants caution when interpreting the unique foot anatomies and foot functions of extinct hominins evidenced by their footprint structures. Further

  1. Magnetic torque on a rotating superconducting sphere

    NASA Technical Reports Server (NTRS)

    Holdeman, L. B.

    1975-01-01

    The London theory of superconductivity is used to calculate the torque on a superconducting sphere rotating in a uniform applied magnetic field. The London theory is combined with classical electrodynamics for a calculation of the direct effect of excess charge on a rotating superconducting sphere. Classical electrodynamics, with the assumption of a perfect Meissner effect, is used to calculate the torque on a superconducting sphere rotating in an arbitrary magnetic induction; this macroscopic approach yields results which are correct to first order. Using the same approach, the torque due to a current loop encircling the rotating sphere is calculated.

  2. How Fo-ATPase generates rotary torque.

    PubMed

    Oster, G; Wang, H; Grabe, M

    2000-04-29

    The F-ATPases synthesize ATP using a transmembrane ionmotive force (IMF) established by the electron transport chain. This transduction involves first converting the IMF to a rotary torque in the transmembrane Fo portion. This torque is communicated from Fo to the F1 portion where the energy is used to release the newly synthesized ATP from the catalytic sites according to Boyer's binding change mechanism. Here we explain the principle by which an IMF generates this rotary torque in the Fo ion engine.

  3. Torquing preload in a lubricated bolt

    NASA Technical Reports Server (NTRS)

    Seegmiller, H. L.

    1978-01-01

    The tension preload obtained by torquing a 7/8 in. diam UNC high strength bolt was determined for lubricated and dry conditions. Consistent preload with a variation of + or - 3% was obtained when the bolt head area was lubricated prior to each torque application. Preload tensions nearly 70% greater than the value predicted with the commonly used formula occurred with the lubricated bolt. A reduction to 39% of the initial preload was observed during 50 torque applications without relubrication. Little evidence of wear was noted after 203 cycles of tightening.

  4. Electromagnetic Torque in Tokamaks with Toroidal Asymmetries

    NASA Astrophysics Data System (ADS)

    Logan, Nikolas Christopher

    Toroidal rotation and rotation shear strongly influences stability and confinement in tokamaks. Breaking of the toroidal symmetry by fields orders of magnitude smaller than the axisymmetric field can, however, produce electromagnetic torques that significantly affect the plasma rotation, stability and confinement. These electromagnetic torques are the study of this thesis. There are two typical types of electromagnetic torques in tokamaks: 1) "resonant torques" for which a plasma current defined by a single toroidal and single poloidal harmonic interact with external currents and 2) "nonresonant torques" for which the global plasma response to nonaxisymmetric fields is phase shifted by kinetic effects that drive the rotation towards a neoclassical offset. This work describes the diagnostics and analysis necessary to evaluate the torque by measuring the rate of momentum transfer per unit area in the vacuum region between the plasma and external currents using localized magnetic sensors to measure the Maxwell stress. These measurements provide model independent quantification of both the resonant and nonresonant electromagnetic torques, enabling direct verification of theoretical models. Measured values of the nonresonant torque are shown to agree well with the perturbed equilibrium nonambipolar transport (PENT) code calculation of torque from cross field transport in nonaxisymmetric equilibria. A combined neoclassical toroidal viscosity (NTV) theory, valid across a wide range of kinetic regimes, is fully implemented for the first time in general aspect ratio and shaped plasmas. The code captures pitch angle resonances, reproducing previously inaccessible collisionality limits in the model. The complete treatment of the model enables benchmarking to the hybrid kinetic MHD stability codes MARS-K and MISK, confirming the energy-torque equivalency principle in perturbed equilibria. Experimental validations of PENT results confirm the torque applied by nonaxisymmetric

  5. Measurement of torque during mandibular distraction.

    PubMed

    Burstein, Fernando D; Lukas, Saylan; Forsthoffer, Dina

    2008-05-01

    In a prospective study, 26 patients aged 9 days to 12 years old underwent mandibular distraction. There were 18 bilateral and 8 unilateral distractions performed. Five patients had previous distraction. Torque measurements were performed during the distraction process. A modest linear increase in torque was noted during the distraction process. Older patients required more torque to achieve the same distraction length as younger patients. The results of this study suggest that distraction forces are relatively modest, which may allow for greater freedom of distractor design.

  6. Application of ultrasound in the assessment of plantar fascia in patients with plantar fasciitis: a systematic review.

    PubMed

    Mohseni-Bandpei, Mohammad Ali; Nakhaee, Masoomeh; Mousavi, Mohammad Ebrahim; Shakourirad, Ali; Safari, Mohammad Reza; Vahab Kashani, Reza

    2014-08-01

    Plantar fasciitis (PFS) is one of the most common causes of heel pain, estimated to affect 10% of the general population during their lifetime. Ultrasound (US) imaging technique is increasingly being used to assess plantar fascia (PF) thickness, monitor the effect of different interventions and guide therapeutic interventions in patients with PFS. The purpose of the present study was to systematically review previously published studies concerning the application of US in the assessment of PF in patients with PFS. A literature search was performed for the period 2000-2012 using the Science Direct, Scopus, PubMed, CINAHL, Medline, Embase and Springer databases. The key words used were: ultrasound, sonography, imaging techniques, ultrasonography, interventional ultrasonography, plantar fascia and plantar fasciitis. The literature search yielded 34 relevant studies. Sixteen studies evaluated the effect of different interventions on PF thickness in patients with PFS using US; 12 studies compared PF thickness between patients with and without PFS using US; 6 studies investigated the application of US as a guide for therapeutic intervention in patients with PFS. There were variations among studies in terms of methodology used. The results indicated that US can be considered a reliable imaging technique for assessing PF thickness, monitoring the effect of different interventions and guiding therapeutic interventions in patients with PFS. Copyright © 2014 World Federation for Ultrasound in Medicine & Biology. Published by Elsevier Inc. All rights reserved.

  7. Direction-Specific Impairments in Cervical Range of Motion in Women with Chronic Neck Pain: Influence of Head Posture and Gravitationally Induced Torque.

    PubMed

    Rudolfsson, Thomas; Björklund, Martin; Svedmark, Åsa; Srinivasan, Divya; Djupsjöbacka, Mats

    2017-01-01

    Cervical range of motion (ROM) is commonly assessed in clinical practice and research. In a previous study we decomposed active cervical sagittal ROM into contributions from lower and upper levels of the cervical spine and found level- and direction-specific impairments in women with chronic non-specific neck pain. The present study aimed to validate these results and investigate if the specific impairments can be explained by the neutral posture (defining zero flexion/extension) or a movement strategy to avoid large gravitationally induced torques on the cervical spine. Kinematics of the head and thorax was assessed in sitting during maximal sagittal cervical flexion/extension (high torque condition) and maximal protraction (low torque condition) in 120 women with chronic non-specific neck pain and 40 controls. We derived the lower and upper cervical angles, and the head centre of mass (HCM), from a 3-segment kinematic model. Neutral head posture was assessed using a standardized procedure. Previous findings of level- and direction-specific impairments in neck pain were confirmed. Neutral head posture was equal between groups and did not explain the direction-specific impairments. The relative magnitude of group difference in HCM migration did not differ between high and low torques conditions, lending no support for our hypothesis that impairments in sagittal ROM are due to torque avoidance behaviour. The direction- and level-specific impairments in cervical sagittal ROM can be generalised to the population of women with non-specific neck pain. Further research is necessary to clarify if torque avoidance behaviour can explain the impairments.

  8. Direction-Specific Impairments in Cervical Range of Motion in Women with Chronic Neck Pain: Influence of Head Posture and Gravitationally Induced Torque

    PubMed Central

    Björklund, Martin; Svedmark, Åsa; Srinivasan, Divya; Djupsjöbacka, Mats

    2017-01-01

    Background Cervical range of motion (ROM) is commonly assessed in clinical practice and research. In a previous study we decomposed active cervical sagittal ROM into contributions from lower and upper levels of the cervical spine and found level- and direction-specific impairments in women with chronic non-specific neck pain. The present study aimed to validate these results and investigate if the specific impairments can be explained by the neutral posture (defining zero flexion/extension) or a movement strategy to avoid large gravitationally induced torques on the cervical spine. Methods Kinematics of the head and thorax was assessed in sitting during maximal sagittal cervical flexion/extension (high torque condition) and maximal protraction (low torque condition) in 120 women with chronic non-specific neck pain and 40 controls. We derived the lower and upper cervical angles, and the head centre of mass (HCM), from a 3-segment kinematic model. Neutral head posture was assessed using a standardized procedure. Findings Previous findings of level- and direction-specific impairments in neck pain were confirmed. Neutral head posture was equal between groups and did not explain the direction-specific impairments. The relative magnitude of group difference in HCM migration did not differ between high and low torques conditions, lending no support for our hypothesis that impairments in sagittal ROM are due to torque avoidance behaviour. Interpretation The direction- and level-specific impairments in cervical sagittal ROM can be generalised to the population of women with non-specific neck pain. Further research is necessary to clarify if torque avoidance behaviour can explain the impairments. PMID:28099504

  9. The variability of the force produced by the plantar flexor muscles does not associate with postural sway in older adults during upright standing.

    PubMed

    Barbosa, Roberto N; Silva, Nilson R S; Santos, Daniel P R; Moraes, Renato; Gomes, Matheus M

    2018-05-31

    The force variability of the plantar flexor muscles (PFM) appears to be directly related to the control of upright standing. Nevertheless, this association is still uncertain in older adults. This study aimed to evaluate the relationship between PFM force variability and postural sway in the upright standing in older women. Forty older women performed submaximal plantar flexion movements measured by force transducers coupled to an experimental chair. They performed this task during three sets of 20 s at 5% and 10% of their maximum voluntary isometric contraction with and without the aid of visual feedback of the force produced. The volunteers then stood barefoot, with eyes closed and feet parallel on a force platform, which allowed the measurement of the center of pressure displacement in the anteroposterior direction. The results did not indicate a significant association between force variability of the PFMs and postural sway in older women. It can be inferred that the force variability of the PFM does not play an important role in controlling the posture in this population, suggesting that other factors may influence the functioning of the postural control system in older adults. Copyright © 2018. Published by Elsevier B.V.

  10. Hardness and posting of foot orthoses modify plantar contact area, plantar pressure, and perceived comfort when cycling.

    PubMed

    Bousie, Jaquelin A; Blanch, Peter; McPoil, Thomas G; Vicenzino, Bill

    2018-07-01

    To evaluate the effects of hardness and posting of orthoses on plantar profile and perceived comfort and support during cycling. A repeated measures study with randomised order of orthoses, hardness, and posting conditions. Twenty-three cyclists cycled at a cadence of 90rpm and a perceived exertion rating of twelve. Contoured soft and hard orthoses with or without a medial forefoot or lateral forefoot post were evaluated. Plantar contact area, mean pressure and peak pressure were measured for nine plantar regions using the pedar ® -X system and represented as a percentage of the total (CA%, MP%, and PP% respectively). Perceived comfort and support was rated on a visual analogue scale. The softer orthosis significantly increased CA% (p=0.014) across the midfoot and heel with a decrease in the toe region and forefoot. MP% (p=0.034) and PP% (p=0.012) were significantly increased at the mid and lateral forefoot with reductions in MP% at the midfoot and in PP% at the hallux and toes. Forefoot posting significantly increased CA% (p=0.018) at the toes and forefoot and decreased it at the heel. PP% was significantly altered (p=0.013) based on posting position. Lateral forefoot posting significantly decreased heel comfort (p=0.036). When cycling, a soft, contoured orthosis increased contact across the midfoot and heel, modulating forefoot and midfoot plantar pressures but not altering comfort or support. Forefoot postings significantly modified contact areas and plantar pressures and reduced comfort at the heel. Copyright © 2017. Published by Elsevier Ltd.

  11. STAPP: Spatiotemporal analysis of plantar pressure measurements using statistical parametric mapping.

    PubMed

    Booth, Brian G; Keijsers, Noël L W; Sijbers, Jan; Huysmans, Toon

    2018-05-03

    Pedobarography produces large sets of plantar pressure samples that are routinely subsampled (e.g. using regions of interest) or aggregated (e.g. center of pressure trajectories, peak pressure images) in order to simplify statistical analysis and provide intuitive clinical measures. We hypothesize that these data reductions discard gait information that can be used to differentiate between groups or conditions. To test the hypothesis of null information loss, we created an implementation of statistical parametric mapping (SPM) for dynamic plantar pressure datasets (i.e. plantar pressure videos). Our SPM software framework brings all plantar pressure videos into anatomical and temporal correspondence, then performs statistical tests at each sampling location in space and time. Novelly, we introduce non-linear temporal registration into the framework in order to normalize for timing differences within the stance phase. We refer to our software framework as STAPP: spatiotemporal analysis of plantar pressure measurements. Using STAPP, we tested our hypothesis on plantar pressure videos from 33 healthy subjects walking at different speeds. As walking speed increased, STAPP was able to identify significant decreases in plantar pressure at mid-stance from the heel through the lateral forefoot. The extent of these plantar pressure decreases has not previously been observed using existing plantar pressure analysis techniques. We therefore conclude that the subsampling of plantar pressure videos - a task which led to the discarding of gait information in our study - can be avoided using STAPP. Copyright © 2018 Elsevier B.V. All rights reserved.

  12. Torque equilibrium attitude control for Skylab reentry

    NASA Technical Reports Server (NTRS)

    Glaese, J. R.; Kennel, H. F.

    1979-01-01

    All the available torque equilibrium attitudes (most were useless from the standpoint of lack of electrical power) and the equilibrium seeking method are presented, as well as the actual successful application during the 3 weeks prior to Skylab reentry.

  13. Noncontact torque measurement using stroboscopic techniques

    NASA Technical Reports Server (NTRS)

    Leonard, W. H.

    1972-01-01

    Noncontact torquemeter measures torsional deflection of rotating shaft and results are viewed on vernier scale. Magnitude of torque must be calculated from measured deflection. Device has no electric connections with the rotating member and is easy to use.

  14. Postoperative Knee Flexion Angle Is Affected by Lateral Laxity in Cruciate-Retaining Total Knee Arthroplasty.

    PubMed

    Nakano, Naoki; Matsumoto, Tomoyuki; Muratsu, Hirotsugu; Takayama, Koji; Kuroda, Ryosuke; Kurosaka, Masahiro

    2016-02-01

    Although many studies have reported that postoperative knee flexion is influenced by preoperative conditions, the factors which affect postoperative knee flexion have not been fully elucidated. We tried to investigate the influence of intraoperative soft tissue balance on postoperative knee flexion angle after cruciate-retaining (CR) total knee arthroplasty (TKA) using a navigation and an offset-type tensor. We retrospectively analyzed 55 patients with osteoarthritis who underwent TKA using e.motion-CR (B. Braun Aesculap, Germany) whose knee flexion angle could be measured at 2 years after operation. The exclusion criteria included valgus deformity, severe bony defect, infection, and bilateral TKA. Intraoperative varus ligament balance and joint component gap were measured with the navigation (Orthopilot 4.2; B. Braun Aesculap) while applying 40-lb joint distraction force at 0° to 120° of knee flexion using an offset-type tensor. Correlations between the soft tissue parameters and postoperative knee flexion angle were analyzed using simple linear regression models. Varus ligament balance at 90° of flexion (R = 0.56; P < .001) and lateral compartment gap at 90° of flexion (R = 0.51; P < .001) were positively correlated with postoperative knee flexion angle. In addition, as with past studies, joint component gap at 90° of flexion (R = 0.30; P < .05) and preoperative knee flexion angle (R = 0.63; P < .001) were correlated with postoperative knee flexion angle. Lateral laxity as well as joint component gap at 90° of flexion is one of the most important factors affecting postoperative knee flexion angle in CR-TKA. Copyright © 2016 Elsevier Inc. All rights reserved.

  15. Shoulder internal rotation elbow flexion test for diagnosing cubital tunnel syndrome.

    PubMed

    Ochi, Kensuke; Horiuchi, Yukio; Tanabe, Aya; Waseda, Makoto; Kaneko, Yasuhito; Koyanagi, Takahiro

    2012-06-01

    Shoulder internal rotation enhances symptom provocation attributed to cubital tunnel syndrome. We present a modified elbow flexion test--the shoulder internal rotation elbow flexion test--for diagnosing cubital tunnel syndrome. Fifty-five ulnar nerves in cubital tunnel syndrome patients and 123 ulnar nerves in controls were examined with 5 seconds each of elbow flexion, shoulder internal rotation, and shoulder internal rotation elbow flexion tests before and after treatment (surgery in 18; conservative in others). For the shoulder internal rotation elbow flexion test position, 90° abduction, maximum internal rotation, and 10° flexion of the shoulder were combined with the elbow flexion test position. The test was considered positive if any symptom for cubital tunnel syndrome developed <5 seconds. Influence of the shoulder internal rotation elbow flexion test was evaluated by nerve conduction studies in 10 cubital tunnel syndrome nerves and 7 control nerves. The sensitivities/specificities of the 5-second elbow flexion, shoulder internal rotation, and shoulder internal rotation elbow flexion tests were 25%/100%, 58%/100%, and 87%/98%, respectively. Sensitivity differences between the shoulder internal rotation elbow flexion test and the other two tests were significant. Shoulder internal rotation elbow flexion test results and cubital tunnel syndrome symptoms were significantly correlated. Influence of the shoulder internal rotation elbow flexion test on the ulnar nerve was seen in 8 of 10 cubital tunnel syndrome nerves but not in controls. The 5-second shoulder internal rotation elbow flexion test is specific, easy and quick provocative test for diagnosing cubital tunnel syndrome. Copyright © 2012 Journal of Shoulder and Elbow Surgery Board of Trustees. Published by Mosby, Inc. All rights reserved.

  16. Fourth-order acoustic torque in intense sound fields

    NASA Technical Reports Server (NTRS)

    Wang, T. G.; Kanber, H.; Olli, E. E.

    1978-01-01

    The observation of a fourth-order acoustic torque in intense sound fields is reported. The torque was determined by measuring the acoustically induced angular deflection of a polished cylinder suspended by a torsion fiber. This torque was measured in a sound field of amplitude greater than that in which first-order acoustic torque has been observed.

  17. Torque and Learning and Behavior Problems in Children.

    ERIC Educational Resources Information Center

    Zendel, Ivan H.; Pihl, R. O.

    1980-01-01

    Findings indicate minimal differences, on diagnostic tests, between children who exhibited torque and those who did not. Torque is defined as the circling of any X in a clockwise direction. Torque is not associated with learning problems in school. Diagnostic utility of torque should be carefully considered. (Author)

  18. Optimal Spacecraft Attitude Control Using Aerodynamic Torques

    DTIC Science & Technology

    2007-03-01

    His design resembles a badminton shuttlecock and “uses passive aerodynamic drag torques to stabilize pitch and yaw” and active magnetic torque...Ravindran’s and Hughes’ ‘arrow-like’ design. Psiaki notes that “this arrow concept has been modified to become a badminton shuttlecock-type design...panels were placed to the rear of the center-of-mass, similar to a badminton shuttlecock, to provide passive stability about the pitch and yaw axes

  19. Knudsen torque on heated micro beams

    SciTech Connect

    Li, Qi; Liang, Tengfei; Ye, Wenjing

    Thermally induced mechanical loading has been shown to have significant effects on micro/nano objects immersed in a gas with a non-uniform temperature field. While the majority of existing studies and related applications focus on forces, we investigate the torque, and thus the rotational motion, produced by such a mechanism. Using the asymptotic analysis in the near continuum regime, the Knudsen torque acting on an asymmetrically located uniformly heated microbeam in a cold enclosure is investigated. The existence of a non-zero net torque is demonstrated. In addition, it has been found that by manipulating the system configuration, the rotational direction ofmore » the torque can be changed. Two types of rotational motion of the microbeam have been identified: the pendulum motion of a rectangular beam, and the unidirectional rotation of a cylindrical beam. A rotational frequency of 4 rpm can be achieved for the cylindrical beam with a diameter of 3μm at Kn = 0.005. Illustrated by the simulations using the direct simulation of Monte Carlo, the Knudsen torque can be much increased in the transition regime, demonstrating the potential of Knudsen torque serving as a rotation engine for micro/nano objects.« less

  20. A flexible wearable sensor for knee flexion assessment during gait.

    PubMed

    Papi, Enrica; Bo, Yen Nee; McGregor, Alison H

    2018-05-01

    Gait analysis plays an important role in the diagnosis and management of patients with movement disorders but it is usually performed within a laboratory. Recently interest has shifted towards the possibility of conducting gait assessments in everyday environments thus facilitating long-term monitoring. This is possible by using wearable technologies rather than laboratory based equipment. This study aims to validate a novel wearable sensor system's ability to measure peak knee sagittal angles during gait. The proposed system comprises a flexible conductive polymer unit interfaced with a wireless acquisition node attached over the knee on a pair of leggings. Sixteen healthy volunteers participated to two gait assessments on separate occasions. Data was simultaneously collected from the novel sensor and a gold standard 10 camera motion capture system. The relationship between sensor signal and reference knee flexion angles was defined for each subject to allow the transformation of sensor voltage outputs to angular measures (degrees). The knee peak flexion angle from the sensor and reference system were compared by means of root mean square error (RMSE), absolute error, Bland-Altman plots and intra-class correlation coefficients (ICCs) to assess test-retest reliability. Comparisons of knee peak flexion angles calculated from the sensor and gold standard yielded an absolute error of 0.35(±2.9°) and RMSE of 1.2(±0.4)°. Good agreement was found between the two systems with the majority of data lying within the limits of agreement. The sensor demonstrated high test-retest reliability (ICCs>0.8). These results show the ability of the sensor to monitor knee peak sagittal angles with small margins of error and in agreement with the gold standard system. The sensor has potential to be used in clinical settings as a discreet, unobtrusive wearable device allowing for long-term gait analysis. Copyright © 2018 The Authors. Published by Elsevier B.V. All rights reserved.

  1. A reactive torque control law for gyroscopically controlled space vehicles

    NASA Technical Reports Server (NTRS)

    Farmer, J. E.

    1973-01-01

    A method of control is developed based on the reactive torques as seen by the individual CMG gimbals. The application of a torque to the gimbal of a CMG rotates the momentum vector and applies a torque to the spacecraft according to well-known laws. The response (rotation) of the vehicle produces a reverse or reaction torque opposing the torque producing the gimbal movement. The reactive torque and the pseudoinverse control schemes are contrasted in order to point out the simplicity of the first method. Simulation was performed only to the extent necessary to prove that reactive torque stabilization and control is feasible.

  2. An exploratory study on differences in cumulative plantar tissue stress between healing and non-healing plantar neuropathic diabetic foot ulcers.

    PubMed

    van Netten, Jaap J; van Baal, Jeff G; Bril, Adriaan; Wissink, Marieke; Bus, Sicco A

    2018-03-01

    Mechanical stress is important in causing and healing plantar diabetic foot ulcers, but almost always studied as peak pressure only. Measuring cumulative plantar tissue stress combines plantar pressure and ambulatory activity, and better defines the load on ulcers. Our aim was to explore differences in cumulative plantar tissue stress between people with healing and non-healing plantar diabetic foot ulcers. We analyzed a subgroup of 31 patients from a randomized clinical trial, treated with a removable offloading device for their plantar diabetic forefoot ulcer. We measured in-device dynamic plantar pressure and daily stride count to calculate cumulative plantar tissue stress at the ulcer location and associated this with ulcer healing and ulcer surface area reduction at four weeks (Student's t and chi-square test for significance, Cohen's d for effect size). In 12 weeks, 68% (n = 21) of the ulcers healed and 32% (n = 10) did not. No statistically significant differences were found for cumulative plantar tissue stress, plantar pressure or ambulatory activity between people with healed and not-healed ulcers. Cumulative plantar tissue stress was 25% lower for people with healed ulcers (155 vs. 207 MPa·s/day; P = 0.71; Effect size: d = 0.29). Post-hoc analyses in the 27 patients who self-reported to be adherent to wearing the device showed that cumulative plantar tissue stress was 49% lower for those who reached ≥75% ulcer surface area reduction at four weeks (140 vs. 275 MPa·s/day; P = 0.09; d = 0.76); smaller differences and effect sizes were found for peak pressure (24%), peak pressure-time integral (30%) and ambulatory activity (26%); (P-value range: 0.14-0.97; Cohen's d range: 0.14-0.70). Measuring cumulative plantar tissue stress may provide insight beyond that obtained from plantar pressure or ambulatory activity alone, with regard to diabetic foot ulcer healing using removable offloading devices. These explorative findings

  3. Extraneous torque and compensation control on the electric load simulator

    NASA Astrophysics Data System (ADS)

    Jiao, Zongxia; Li, Chenggong; Ren, Zhiting

    2003-09-01

    In this paper a novel motor-drive load simulator based on compensation control strategy is proposed and designed. Through analyzing the torque control system consisting of DC torque motor, PWM module and torque sensor, it is shown that performance of the motor-drive load simulator is possible to be as good as that of the electro-hydraulic load simulator in the range of small torque. In the course of loading, the rotation of the actuator would cause a strong disturbance torque through the motor back-EMF, which produces extraneous torque similar as in electro-hydraulic load simulator. This paper analyzes the cause of extraneous torque inside the torque motor in detail and presents an appropriate compensation control with which the extraneous torque can be compensated and the good performance of the torque control system can be obtained. The results of simulation indicate that the compensation is very effective and the track performance is according with the request.

  4. [Microsurgery for severe flexion contracture of proximal interphalangeal joint].

    PubMed

    Fei, Xiaoxuan; Feng, Shiming; Gao, Shunhong

    2012-07-01

    To investigate the clinical results of cross-finger flap combined with laterodigital pedicled skin flap for repair of severe flexion contracture of the proximal interphalangeal joint. Between October 2008 and February 2011, 11 patients (11 fingers) with severe flexion contracture of the proximal interphalangeal joint were treated with cross-finger flap combined with laterodigital pedicled skin flap. There were 7 males and 4 females, aged 20-63 years (mean, 32.6 years). The causes of injury were crush or electric-saw injury in 7 cases, burn or explosive injury in 3 cases, and electrical injury in 1 case. The locations were the index finger in 4 cases, the middle finger in 2 cases, the ring finger in 2 cases, and the little finger in 3 cases. The mean disease duration was 12.4 months (range, 6-24 months). All cases were rated as type III according to Stern classification standard. The volar tissue defect ranged from 3.0 cm x 1.5 cm to 5.0 cm x 2.5 cm, with exposed tendons, nerves, vessels, or bone after scar relaxation. The defects were repaired with cross-finger flaps (2.2 cm x 1.8 cm to 3.8 cm x 2.5 cm) combined with laterodigital pedicled skin flaps (1.5 cm x 1.2 cm to 2.5 cm x 2.0 cm). Double laterodigital pedicled skin flaps were used in 3 cases. The flap donor site was sutured directly or repaired with the skin graft. All flaps survived completely and wound healed by first intention. The donor skin graft survived. All the patients were followed up 6-18 months (mean, 11.3 months). The finger appearance was satisfactory. The flaps had soft texture and good color in all cases. No obvious pigmentation or contraction was observed. The contracted fingers could extend completely with good active flexion and extension motion. At last follow-up, the extension of the proximal interphalangeal joint was 10-150. Based on proximal interphalangeal joint motion standard of Chinese Medical Association for hand surgery, the results were excellent in 6 cases, good in 4 cases, and

  5. Influence of obstructive sleep apnea syndrome in the fluctuation of the submaximal isometric torque of knee extensors in patients with early-grade osteoarthritis

    PubMed Central

    Silva, Andressa; Mello, Marco T.; Serrão, Paula R.; Luz, Roberta P.; Bittencourt, Lia R.; Mattiello, Stela M.

    2015-01-01

    OBJECTIVE: The aim of this study was to investigate whether obstructive sleep apnea (OSA) alters the fluctuation of submaximal isometric torque of the knee extensors in patients with early-grade osteoarthritis (OA). METHOD: The study included 60 male volunteers, aged 40 to 70 years, divided into four groups: Group 1 (G1) - Control (n=15): without OA and without OSA; Group 2 (G2) (n=15): with OA and without OSA; Group 3 (G3) (n=15): without OA and with OSA; and Group 4 (G4) (n=15) with OA and with OSA. Five patients underwent maximal isometric contractions of 10 seconds duration each, with the knee at 60° of flexion to determine peak torque at 60°. To evaluate the fluctuation of torque, 5 submaximal isometric contractions (50% of maximum peak torque) of 10 seconds each, which were calculated from the standard deviation of torque and coefficient of variation, were performed. RESULTS: Significant differences were observed between groups for maximum peak torque, while G4 showed a lower value compared with G1 (p=0.005). Additionally, for the average torque exerted, G4 showed a lower value compared to the G1 (p=0.036). However, no differences were found between the groups for the standard deviation (p=0.844) and the coefficient of variation (p=0.143). CONCLUSION: The authors concluded that OSA did not change the parameters of the fluctuation of isometric submaximal torque of knee extensors in patients with early-grade OA. PMID:26443974

  6. Endoscopic Debridement for Treatment of Chronic Plantar Fasciitis: An Innovative Surgical Technique.

    PubMed

    Cottom, James M; Maker, Jared M

    2016-01-01

    Plantar fasciitis is one the most common pathologies seen by foot and ankle surgeons. When nonoperative therapy fails, surgical intervention is warranted. Various surgical procedures are available for the treatment of recalcitrant plantar fasciitis. The most common surgical management typically consists of open versus endoscopic plantar fascia release. The documented comorbidities associated with the release of the plantar fascia include lateral column overload and metatarsalgia. We present a new technique for this painful condition that is minimally invasive, allows visualization of the plantar fascia, and maintains the integrity of this fascia. Our hypothesis was that the use of endoscopic debridement of the plantar fascia would provide a minimally invasive technique with acceptable patient outcomes. Copyright © 2016 American College of Foot and Ankle Surgeons. Published by Elsevier Inc. All rights reserved.

  7. Torque equilibrium attitudes for the Space Station

    NASA Technical Reports Server (NTRS)

    Thompson, Roger C.

    1993-01-01

    All spacecraft orbiting in a low earth orbit (LEO) experience external torques due to environmental effects. Examples of these torques include those induced by aerodynamic, gravity-gradient, and solar forces. It is the gravity-gradient and aerodynamic torques that produce the greatest disturbances to the attitude of a spacecraft in LEO, and large asymmetric spacecraft, such as the space station, are affected to a greater degree because the magnitude of the torques will, in general, be larger in proportion to the moments of inertia. If left unchecked, these torques would cause the attitude of the space station to oscillate in a complex manner and the resulting motion would destroy the micro-gravity environment as well as prohibit the orbiter from docking. The application of control torques will maintain the proper attitude, but the controllers have limited momentum capacity. When any controller reaches its limit, propellant must then be used while the device is reset to a zero or negatively-biased momentum state. Consequently, the rate at which momentum is accumulated is a significant factor in the amount of propellant used and the frequency of resupply necessary to operate the station. A torque profile in which the area curve for a positive torque is not equal to the area under the curve for a negative torque is 'biased,' and the consequent momentum build-up about that axis is defined as secular momentum because it continues to grow with time. Conversely, when the areas are equal, the momentum is cyclic and bounded. A Torque Equilibrium Attitude (TEA) is thus defined as an attitude at which the external torques 'balance' each other as much as possible, and which will result in lower momentum growth in the controllers. Ideally, the positive and negative external moments experienced by a spacecraft at the TEA would exactly cancel each other out and small cyclic control torques would be required only for precise attitude control. Over time, the only momentum build

  8. Ultrasound-guided injection for plantar fasciitis: A brief review

    PubMed Central

    Nair, AS; Sahoo, RK

    2016-01-01

    Plantar fasciitis (PF) is a distressing condition experienced by many patients. Although self-limiting, it tends to become a chronic ailment if the precipitating factors are not addressed. One of the modality of treating PF is intra-lesional corticosteroid injection. This was done using palpation technique earlier but nowadays many specialists use ultrasound (US) imaging as a guide to give injection accurately instead of inadvertently damaging the plantar fascia or injecting into surrounding soft tissue, both of which can have serious implications. We did a literature search in Medline, Scopus, and Embase databases to find out articles describing US-guided corticosteroid injection for treating PF and whether guided injection was effective than injection given by palpation. PMID:27833490

  9. Plantar fascia rupture in a professional soccer player.

    PubMed

    Suzue, Naoto; Iwame, Toshiyuki; Kato, Kenji; Takao, Shoichiro; Tateishi, Tomohiko; Takeda, Yoshitsugu; Hamada, Daisuke; Goto, Tomohiro; Takata, Yoichiro; Matsuura, Tetsuya; Sairyo, Koichi

    2014-01-01

    We report the case of a 29-year-old male professional soccer player who presented with symptoms of plantar fasciitis. His symptoms occurred with no remarkable triggers and gradually worsened despite conservative treatments including taping, use of insoles, and physical therapy. Local corticosteroid injection was given twice as a further intervention, but his plantar fascia partially ruptured 49 days after the second injection. He was treated conservatively with platelet-rich plasma, and magnetic resonance imaging showed regenerative change of the ruptured fascia. Five months after the rupture, he returned to his original level of training. If professional athletes find it difficult to refrain from athletic activity, as in the present case, the risk of rupture due to corticosteroid injection should not be overlooked.

  10. Magnetic resonance imaging of the posterior cruciate ligament in flexion.

    PubMed

    Craddock, William; Smithers, Troy; Harris, Craig; du Moulin, William; Molnar, Robert

    2018-06-01

    Posterior cruciate ligament (PCL) injuries of the knee are common and sometimes difficult to diagnose. Magnetic resonance imaging (MRI), performed using standard orthogonal plane views, is the investigation of choice. It can be particularly difficult to differentiate acute partial and complete tears and identify elongation of chronic healed tears. The aim of the paper is to describe a new method of positioning the patient with the knee flexed at 90°, allowing the PCL to be visualised in a position of greatest length and tension which may assist in differentiating and identifying these injuries. Four symptomatic patients with suspected PCL injuries, two acute and two chronic, were MRI scanned using a routine protocol with the knee in extension before performing oblique sagittal fast spin-echo (FSE) proton-density (PD) sequences with the knee positioned in 90° of flexion. The appearance of the PCLs were then qualitatively assessed. MRI scanning with the knee in flexion identified more extensive PCL injury than standard imaging. In the two patients with acute injuries, partial tears on the standard orthogonal plane views were found to be complete ruptures. In the two patients with chronic injuries, elongation of the PCL not identifiable on the standard orthogonal plane views was apparent. MRI scanning of the PCL with the knee flexed at 90° may help in differentiating partial and complete ruptures of the PCL and identifying elongation of the PCL in chronic injuries. Copyright © 2018 Elsevier B.V. All rights reserved.

  11. Velocity of lordosis angle during spinal flexion and extension.

    PubMed

    Consmüller, Tobias; Rohlmann, Antonius; Weinland, Daniel; Druschel, Claudia; Duda, Georg N; Taylor, William R

    2012-01-01

    The importance of functional parameters for evaluating the severity of low back pain is gaining clinical recognition, with evidence suggesting that the angular velocity of lordosis is critical for identification of musculoskeletal deficits. However, there is a lack of data regarding the range of functional kinematics (RoKs), particularly which include the changing shape and curvature of the spine. We address this deficit by characterising the angular velocity of lordosis throughout the thoracolumbar spine according to age and gender. The velocity of lumbar back shape changes was measured using Epionics SPINE during maximum flexion and extension activities in 429 asymptomatic volunteers. The difference between maximum positive and negative velocities represented the RoKs. The mean RoKs for flexion decreased with age; 114°/s (20-35 years), 100°/s (36-50 years) and 83°/s (51-75 years). For extension, the corresponding mean RoKs were 73°/s, 57°/s and 47°/s. ANCOVA analyses revealed that age and gender had the largest influence on the RoKs (p<0.05). The Epionics SPINE system allows the rapid assessment of functional kinematics in the lumbar spine. The results of this study now serve as normative data for comparison to patients with spinal pathology or after surgical treatment.

  12. Decoding flexion of individual fingers using electrocorticographic signals in humans

    NASA Astrophysics Data System (ADS)

    Kubánek, J.; Miller, K. J.; Ojemann, J. G.; Wolpaw, J. R.; Schalk, G.

    2009-12-01

    Brain signals can provide the basis for a non-muscular communication and control system, a brain-computer interface (BCI), for people with motor disabilities. A common approach to creating BCI devices is to decode kinematic parameters of movements using signals recorded by intracortical microelectrodes. Recent studies have shown that kinematic parameters of hand movements can also be accurately decoded from signals recorded by electrodes placed on the surface of the brain (electrocorticography (ECoG)). In the present study, we extend these results by demonstrating that it is also possible to decode the time course of the flexion of individual fingers using ECoG signals in humans, and by showing that these flexion time courses are highly specific to the moving finger. These results provide additional support for the hypothesis that ECoG could be the basis for powerful clinically practical BCI systems, and also indicate that ECoG is useful for studying cortical dynamics related to motor function.

  13. Nociceptive flexion reflexes during analgesic neurostimulation in man.

    PubMed

    García-Larrea, L; Sindou, M; Mauguière, F

    1989-11-01

    Nociceptive flexion reflexes of the lower limbs (RIII responses) have been studied in 21 patients undergoing either epidural (DCS, n = 16) or transcutaneous (TENS, n = 5) analgesic neurostimulation (AN) for chronic intractable pain. Flexion reflex RIII was depressed or suppressed by AN in 11 patients (52.4%), while no modification was observed in 9 cases and a paradoxical increase during AN was evidenced in 1 case. In all but 2 patients, RIII changes were rapidly reversible after AN interruption. RIII depression was significantly associated with subjective pain relief, as assessed by conventional self-rating; moreover, in 2 patients it was possible to ameliorate the pain-suppressing effects of AN by selecting those stimulation parameters (intensity and frequency) that maximally depressed nociceptive reflex RIII. We recorded 2 cases of RIII attenuation after contralateral neurostimulation. AN appeared to affect nociceptive reflexes rather selectively, with no or very little effect on other cutaneous, non-nociceptive responses. Recording of RIII reflexes is relatively simple to implement as a routine paraclinical procedure. It facilitates the objective assessment of AN efficacy and may help to choose the most appropriate parameters of neurostimulation. In addition, RIII behavior in patients could be relevant to the understanding of some of the mechanisms involved in AN-induced pain relief.

  14. Muscle recruitment variations during wrist flexion exercise: MR evaluation

    NASA Technical Reports Server (NTRS)

    Fleckenstein, J. L.; Watumull, D.; Bertocci, L. A.; Nurenberg, P.; Peshock, R. M.; Payne, J. A.; Haller, R. G.; Blomqvist, C. G. (Principal Investigator)

    1994-01-01

    OBJECTIVE: Many exercise protocols used in physiological studies assume homogeneous and diffuse muscle recruitment. To test this assumption during a "standard" wrist flexion protocol, variations in muscle recruitment were assessed using MRI in eight healthy subjects. MATERIALS AND METHODS: Variations were assessed by comparing the right to the left forearms and the effect of slight (15 degrees) pronation or supination at the wrist. RESULTS: Postexercise imaging showed focal regions of increased signal intensity (SI), indicating relatively strong recruitment, most often in entire muscles, although occasionally only in subvolumes of muscles. In 15 of 26 studies, flexor carpi radialis (FCR) showed more SI than flexor carpi ulnaris, while in 11 studies SI in these muscles increased equivalently. Relatively greater FCR recruitment was seen during pronation and/or use of the nondominant side. Palmaris longus, a wrist flexor, did not appear recruited in 4 of 11 forearms in which it was present. A portion of the superficial finger flexor became hyperintense in 89% of studies, while recruitment of the deep finger flexor was seen only in 43%. CONCLUSION: Inter- and intraindividual variations in forearm muscle recruitment should be anticipated in physiological studies of standard wrist flexion exercise protocols.

  15. Plantar pressure changes after long-distance walking.

    PubMed

    Stolwijk, Niki M; Duysens, Jacques; Louwerens, Jan Willem K; Keijsers, Noël L W

    2010-12-01

    The popularity of long-distance walking (LDW) has increased in the last decades. However, the effects of LDW on plantar pressure distribution and foot complaints, in particular, after several days of walking, have not been studied. We obtained the plantar pressure data of 62 subjects who had no history of foot complaints and who walked a total distance of 199.8 km for men (n = 30) and 161.5 km for women (n = 32) during four consecutive days. Plantar pressure was measured each day after the finish (posttests I–IV) and compared with the baseline plantar pressure data, which was obtained 1 or 2 d before the march (pretest). Mean, peak, and pressure–time integral per pixel as well as the center of pressure (COP) trajectory of each foot per measurement day were calculated using the normalization method of Keijsers et al. A paired t-test with an adjusted P value was used to detect significant differences between pretest and posttest. Short-term adjustment to LDW resulted in a significant decreased loading on the toes accompanied with an increased loading on the metatarsal head III–V (P < 0.001). At all stages, particularly at later stages, there was significantly more heel loading (P < 0.001). Furthermore, the COP significantly displaced in the posterior direction but not in the mediolateral direction after marching. Contact time increased slightly from 638.5 +/- 24.2 to 675.4 +/- 22.5 ms (P < 0.001). The increased heel loading and decreased function of the toes found after marching indicate a change of walking pattern with less roll-off. It is argued that these changes reflect the effect of fatigue of the lower leg muscles and to avoid loading of the most vulnerable parts of the foot.

  16. Shock wave therapy for chronic proximal plantar fasciitis.

    PubMed

    Ogden, J A; Alvarez, R; Levitt, R; Cross, G L; Marlow, M

    2001-06-01

    Three hundred two patients with chronic heel pain caused by proximal plantar fasciitis were enrolled in a study to assess the treatment effects consequent to administration of electrohydraulicall-generated extracorporeal shock waves. Symptoms had been present from 6 months to 18 years. Each treated patient satisfied numerous inclusion and exclusion criteria before he or she was accepted into this study, which was approved by the Food and Drug Administration as a randomized, double-blind evaluation of the efficacy of shock wave therapy for this disorder. Overall, at the predetermined evaluation period 3 months after one treatment, 56% more of the treated patients had a successful result by all four of the evaluation criteria when compared with the patients treated with a placebo. This difference was significant and corroborated the fact that this difference in the results was specifically attributable to the shock wave treatment, rather than any natural improvement caused by the natural history of the condition. The current study showed that the directed application of electrohydraulic-generated shock waves to the insertion of the plantar fascia onto the calcaneus is a safe and effective nonsurgical method for treating chronic, recalcitrant heel pain syndrome that has been present for at least 6 months and has been refractory to other commonly used nonoperative therapies. This technology, when delivered using the OssaTron (High Medical Technology, Kreuz-lingen, Switzerland), has been approved by the Food and Drug Administration specifically for the treatment of chronic proximal plantar fasciitis. The results suggest that this therapeutic modality should be considered before any surgical options, and even may be preferable to cortisone injection, which has a recognized risk of rupture of the plantar fascia and recurrence of symptoms.

  17. Innovations in plantar pressure and foot temperature measurements in diabetes.

    PubMed

    Bus, S A

    2016-01-01

    Plantar pressure and temperature measurements in the diabetic foot primarily contribute to identifying abnormal values that increase risk for foot ulceration, and they are becoming increasingly more integrated in clinical practice and daily life of the patient. While plantar pressure measurements have long been present, only recently evidence shows their importance in ulcer prevention, as a data-driven approach to therapeutic footwear provision. The long-term monitoring of plantar pressures with the option to provide feedback, when alarming pressure levels occur, is a promising development in this area, although more technical and clinical validation is required. Shear is considered important in ulcer aetiology but is technically difficult to measure. Innovative research is underway to assess if foot temperature can act as a useful surrogate for shear. Because the skin heats up before it breaks down, frequent monitoring of foot temperature can identify these warning signals. This approach has shown to be effective in preventing foot ulcers. Innovation in diagnostic methods for foot temperature monitoring and evidence on cost effectiveness will likely facilitate implementation. Finally, monitoring of adherence to offloading treatment using temperature-based sensors has proven to be a feasible and relevant method with a wide range of possible research and patient care applications. These innovations in plantar pressure and temperature measurements illustrate an important transfer in diabetic foot care from subjective to objective evaluation of the high-risk patient. They demonstrate clinical value and a large potential in helping to reduce the patient and economic burden of diabetic foot disease. Copyright © 2016 John Wiley & Sons, Ltd.

  18. A method to accurately estimate the muscular torques of human wearing exoskeletons by torque sensors.

    PubMed

    Hwang, Beomsoo; Jeon, Doyoung

    2015-04-09

    In exoskeletal robots, the quantification of the user's muscular effort is important to recognize the user's motion intentions and evaluate motor abilities. In this paper, we attempt to estimate users' muscular efforts accurately using joint torque sensor which contains the measurements of dynamic effect of human body such as the inertial, Coriolis, and gravitational torques as well as torque by active muscular effort. It is important to extract the dynamic effects of the user's limb accurately from the measured torque. The user's limb dynamics are formulated and a convenient method of identifying user-specific parameters is suggested for estimating the user's muscular torque in robotic exoskeletons. Experiments were carried out on a wheelchair-integrated lower limb exoskeleton, EXOwheel, which was equipped with torque sensors in the hip and knee joints. The proposed methods were evaluated by 10 healthy participants during body weight-supported gait training. The experimental results show that the torque sensors are to estimate the muscular torque accurately in cases of relaxed and activated muscle conditions.

  19. A Method to Accurately Estimate the Muscular Torques of Human Wearing Exoskeletons by Torque Sensors

    PubMed Central

    Hwang, Beomsoo; Jeon, Doyoung

    2015-01-01

    In exoskeletal robots, the quantification of the user’s muscular effort is important to recognize the user’s motion intentions and evaluate motor abilities. In this paper, we attempt to estimate users’ muscular efforts accurately using joint torque sensor which contains the measurements of dynamic effect of human body such as the inertial, Coriolis, and gravitational torques as well as torque by active muscular effort. It is important to extract the dynamic effects of the user’s limb accurately from the measured torque. The user’s limb dynamics are formulated and a convenient method of identifying user-specific parameters is suggested for estimating the user’s muscular torque in robotic exoskeletons. Experiments were carried out on a wheelchair-integrated lower limb exoskeleton, EXOwheel, which was equipped with torque sensors in the hip and knee joints. The proposed methods were evaluated by 10 healthy participants during body weight-supported gait training. The experimental results show that the torque sensors are to estimate the muscular torque accurately in cases of relaxed and activated muscle conditions. PMID:25860074

  20. Low mass planet migration in magnetically torqued dead zones - I. Static migration torque

    NASA Astrophysics Data System (ADS)

    McNally, Colin P.; Nelson, Richard P.; Paardekooper, Sijme-Jan; Gressel, Oliver; Lyra, Wladimir

    2017-12-01

    Motivated by models suggesting that the inner planet forming regions of protoplanetary discs are predominantly lacking in viscosity-inducing turbulence, and are possibly threaded by Hall-effect generated large-scale horizontal magnetic fields, we examine the dynamics of the corotation region of a low-mass planet in such an environment. The corotation torque in an inviscid, isothermal, dead zone ought to saturate, with the libration region becoming both symmetrical and of a uniform vortensity, leading to fast inward migration driven by the Lindblad torques alone. However, in such a low viscosity situation, the material on librating streamlines essentially preserves its vortensity. If there is relative radial motion between the disc gas and the planet, the librating streamlines will no longer be symmetrical. Hence, if the gas is torqued by a large-scale magnetic field so that it undergoes a net inflow or outflow past the planet, driving evolution of the vortensity and inducing asymmetry of the corotation region, the corotation torque can grow, leading to a positive torque. In this paper, we treat this effect by applying a symmetry argument to the previously studied case of a migrating planet in an inviscid disc. Our results show that the corotation torque due to a laminar Hall-induced magnetic field in a dead zone behaves quite differently from that studied previously for a viscous disc. Furthermore, the magnetic field induced corotation torque and the dynamical corotation torque in a low viscosity disc can be regarded as one unified effect.

  1. Plantar pressures in children with and without sever's disease.

    PubMed

    Becerro de Bengoa Vallejo, Ricardo; Losa Iglesias, Marta Elena; Rodríguez Sanz, David; Prados Frutos, Juan Carlos; Salvadores Fuentes, Paloma; Chicharro, José López

    2011-01-01

    a case-control study was conducted to compare static plantar pressures and distribution of body weight across the two lower limbs, as well as the prevalence of gastrocnemius soleus equinus, in children with and without calcaneal apophysitis (Sever's disease). the participants were 54 boys enrolled in a soccer academy, of which eight were lost to follow-up. Twenty-two boys with unilateral Sever's disease comprised the Sever's disease group and 24 healthy boys constituted a control group. Plantar pressure data were collected using pedobarography, and gastrocnemius soleus equinus was assessed. peak pressure and percentage of body weight supported were significantly higher in the symptomatic feet of the Sever's disease group than in the asymptomatic feet of the Sever's disease group and the control group. Every child in the Sever's disease group had bilateral gastrocnemius equinus, while nearly all children in the control group had no equinus. high plantar foot pressures are associated with Sever's disease, although it is unclear whether they are a predisposing factor or a result of the condition. Gastrocnemius equinus may be a predisposing factor for Sever's disease. Further research is needed to identify other factors involved in the disease and to better understand the factors that contribute to abnormal distribution of body weight in the lower limbs.

  2. Overload protection: avoidance response to heavy plantar surface loading.

    PubMed

    Robbins, S E; Hanna, A M; Gouw, G J

    1988-02-01

    Current footwear which are designed for use in running are examples of intentional biomechanical model integration into device design. The inadequacy of this footwear in protecting against injury is postulated to be due to fixation on inadequate models of locomotory biomechanics that do not provide for feedback control; in particular, an hypothesized plantar surface sensory-mediated feedback control system, which imparts overload protection during locomotion. A heuristic approach was used to identify the hypothesized system. A random series of loads (0 to 164 kg) was applied to the knee flexed at 90 degrees. In this testing system, plantar surface avoidance behavior was the difference between the sum of the leg weight and the load applied to the knee, and the load measured at the plantar surface; this was produced by activation of hip flexors. Significant avoidance behavior was found in all of the subjects (P less than 0.001). On all surfaces tested, including modern athletic footwear (P less than 0.001), its magnitude increased directly in relation to the load applied to the knee (P less than 0.001). There were significant differences in avoidance behavior in relation to the weight-bearing surfaces tested (P less than 0.05). With the identification of a feedback control system which would serve to moderate loading during locomotion, an explanation is provided as to why current athletic footwear do not protect and may be injurious; thus allowing the design of footwear which may be truly protective.

  3. Novel and Conservative Approaches Towards Effective Management of Plantar Fasciitis.

    PubMed

    Assad, Salman; Ahmad, Awaiz; Kiani, Immad; Ghani, Usman; Wadhera, Vikram; Tom, Todd N

    2016-12-05

    We assessed the effectiveness of the different treatments for plantar fasciitis (PF) based on the changes in functional outcomes. A systematic literature search was carried out and studies from 2010 to 2016 were included in this review. The databases from Google Scholar, PubMed and Cochrane were used for the various treatment modalities of plantar fasciitis. The objectives measured included visual analog scale (VAS), Roles and Maudsley scale, foot function index (FFI), plantar fascia thickness and American Orthopedic Foot and Ankle Society (AOFAS) ankle-hind foot scale as the tools to predict the improvement in symptoms of pain and discomfort. Eight randomized controlled trails that met the selection criteria were included in this review. Extracorporeal shock wave lithotripsy (ESWL) with botulinum toxin type A, corticosteroid injections, autologous whole blood and plasma treatment, novel treatments like cryopreserved human amniotic membrane, effect of placebo, platelet rich plasma injections and corticosteroid injections, physiotherapy and high strength training were analyzed. All the treatment modalities applied did lead to the reduction in pain scores, but for long term management autologous condition plasma and platelet rich plasma are the preferred treatment options. Impact of physiotherapy and high strength training is equivalent to corticosteroid injections and hence is suited for patients avoiding invasive forms of treatment.

  4. Novel and Conservative Approaches Towards Effective Management of Plantar Fasciitis

    PubMed Central

    Ahmad, Awaiz; Kiani, Immad; Ghani, Usman; Wadhera, Vikram; Tom, Todd N

    2016-01-01

    We assessed the effectiveness of the different treatments for plantar fasciitis (PF) based on the changes in functional outcomes. A systematic literature search was carried out and studies from 2010 to 2016 were included in this review. The databases from Google Scholar, PubMed and Cochrane were used for the various treatment modalities of plantar fasciitis. The objectives measured included visual analog scale (VAS), Roles and Maudsley scale, foot function index (FFI), plantar fascia thickness and American Orthopedic Foot and Ankle Society (AOFAS) ankle-hind foot scale as the tools to predict the improvement in symptoms of pain and discomfort. Eight randomized controlled trails that met the selection criteria were included in this review. Extracorporeal shock wave lithotripsy (ESWL) with botulinum toxin type A, corticosteroid injections, autologous whole blood and plasma treatment, novel treatments like cryopreserved human amniotic membrane, effect of placebo, platelet rich plasma injections and corticosteroid injections, physiotherapy and high strength training were analyzed. All the treatment modalities applied did lead to the reduction in pain scores, but for long term management autologous condition plasma and platelet rich plasma are the preferred treatment options. Impact of physiotherapy and high strength training is equivalent to corticosteroid injections and hence is suited for patients avoiding invasive forms of treatment.  PMID:28083457

  5. Assessment of mechanical strain in the intact plantar fascia.

    PubMed

    Clark, Ross A; Franklyn-Miller, Andrew; Falvey, Eanna; Bryant, Adam L; Bartold, Simon; McCrory, Paul

    2009-09-01

    A method of measuring tri-axial plantar fascia strain that is minimally affected by external compressive force has not previously been reported. The purpose of this study was to assess the use of micro-strain gauges to examine strain in the different axes of the plantar fascia. Two intact limbs from a thawed, fresh-frozen cadaver were dissected, and a combination of five linear and one three-way rosette gauges were attached to the fascia of the foot and ankle. Strain was assessed during two trials, both consisting of an identical controlled, loaded dorsiflexion. An ICC analysis of the results revealed that the majority of gauge placement sites produced reliable measures (ICC>0.75). Strain mapping of the plantar fascia indicates that the majority of the strain is centrally longitudinal, which provides supportive evidence for finite element model analysis. Although micro-strain gauges do possess the limitation of calibration difficulty, they provide a repeatable measure of fascial strain and may provide benefits in situations that require tri-axial assessment or external compression.

  6. First Tarsometatarsal Arthrodesis: An Anatomic Evaluation of Dorsomedial Versus Plantar Plating.

    PubMed

    Simons, Paul; Fröber, Rosemarie; Loracher, Clemens; Knobe, Matthias; Gras, Florian; Hofmann, Gunther O; Klos, Kajetan

    2015-01-01

    Fusion of the first tarsometatarsal joint is a widely used procedure for the correction of hallux valgus deformity. Although dorsomedial H-shaped plating systems are being increasingly used, fusion can also be achieved by plantar plating. The goal of the present study was to compare these 2 operative techniques based on the anatomic considerations and show the potential pitfalls of both procedures. Six pairs of deep-frozen human lower legs were used in the present cadaveric study. In a randomized manner, either dorsomedial arthrodesis or plantar plating through a medial incision was performed. With regard to arterial injury, the plantar technique resulted in fewer lesions (plantar, 4 injuries [66.7%] to the terminal branches of the first digital branch of the medial plantar artery; dorsomedial, 3 injuries [50%] to the main trunks of the plantar metatarsal arteries and the first dorsal metatarsal artery). With respect to injury to the veins, the plantar procedure affected significantly fewer high-caliber subcutaneous trunk veins. The nerves coursing through the operative field, such as the saphenous and superficial fibular nerves, were compromised more often by the dorsal approach. Neither the plantar plating nor the dorsomedial plating technique was associated with injury to the insertion of the tibialis anterior muscle. Both studied techniques are safe, well-established procedures. Arthrodesis with plantar plating, however, offers additional advantages and is a reliable tool in the foot and ankle surgeon's repertoire. Copyright © 2015 American College of Foot and Ankle Surgeons. Published by Elsevier Inc. All rights reserved.

  7. Biomechanical consequences of plantar fascial release or rupture during gait. Part II: alterations in forefoot loading.

    PubMed

    Sharkey, N A; Donahue, S W; Ferris, L

    1999-02-01

    With a model using feet from cadavers, we tested the hypothesis that plantar fascial release or rupture alters the loading environment of the forefoot during the latter half of the stance phase of gait. The model simulated the position and loading environment of the foot at two instants: early in terminal stance immediately after heel-off and late in terminal stance just preceding contralateral heel strike. Eight feet were loaded at both positions by simulated plantar flexor contraction, and the distribution of plantar pressure was measured before and after progressive release of the plantar fascia. Strain in the diaphysis of the second metatarsal was also measured, from which the bending moments and axial force imposed on the metatarsal were calculated. Cutting the medial half of the central plantar fascial band significantly increased peak pressure under the metatarsal heads but had little effect on pressures in other regions of the forefoot or on second metatarsal strain and loading. Dividing the entire central band or completely releasing the plantar fascia from the calcaneus had a much greater effect and caused significant shifts in plantar pressure and force from the toes to beneath the metatarsal heads. These shifts were accompanied by significantly increased strain and bending in the second metatarsal. Complete fasciotomy increased the magnitude of strain in the dorsal aspect of the second metatarsal by more than 80%, suggesting that plantar fascial release or rupture accelerates the accumulation of fatigue damage in these bones. Altered forefoot loading may be a potential complication of plantar fasciotomy.

  8. Applicability of contrast-enhanced ultrasound in the diagnosis of plantar fasciitis.

    PubMed

    Broholm, R; Pingel, J; Simonsen, L; Bülow, J; Johannsen, F

    2017-12-01

    Contrast-enhanced ultrasound (CEUS) is used to visualize the microvascularization in various tissues. The purpose of this study was to investigate whether CEUS could be used to visualize the microvascular volume (MV) in the plantar fascia, and to compare the method to clinical symptoms and B-mode ultrasound (US) in patients with plantar fasciitis (PF). Twenty patients with unilateral PF were included and were divided by US in insertional thickening (10), midsubstance thickening (5), and no US changes (5). The MV was measured simultaneously in both heels. Four areas in the plantar fascia and plantar fat pad were measured independently by two observers. Inter- and intra-observer correlation analyses were performed. The asymptomatic heels showed a constantly low MV, and for the whole group of patients, a significantly higher MV was found in the symptomatic plantar fascia and plantar fat pad. Inter-observer correlation as well as intra-observer agreement was excellent. The MV in the plantar fascia and plantar fat pad can be measured reliably using CEUS, suggesting that it is a reproducible method to examine patients with plantar fasciitis. © 2017 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

  9. Sonographically guided deep plantar fascia injections: where does the injectate go?

    PubMed

    Maida, Eugene; Presley, James C; Murthy, Naveen; Pawlina, Wojciech; Smith, Jay

    2013-08-01

    To determine the distribution of sonographically guided deep plantar fascia injections in an unembalmed cadaveric model. A single experienced operator completed 10 sonographically guided deep plantar fascia injections in 10 unembalmed cadaveric specimens (5 right and 5 left) obtained from 6 donors (2 male and 4 female) aged 49 to 95 years (mean, 77.5 years) with a mean body mass index of 23.2 kg/m(2) (range, 18.4-26.3 kg/m(2)). A 12-3-MHz linear array transducer was used to direct a 22-gauge, 38-mm stainless steel needle deep to the plantar fascia at the anterior aspect of the calcaneus using an in-plane, medial-to-lateral approach. In each case, 1.5 mL of 50% diluted colored latex was injected deep to the plantar fascia. After a minimum of 72 hours, study coinvestigators dissected each specimen to assess injectate placement. All 10 injections accurately placed latex adjacent to the deep side of the plantar fascia at the anterior calcaneus. However, the flexor digitorum brevis (FDB) origin from the plantar fascia variably limited direct latex contact with the plantar fascia, and small amounts of latex interdigitated with the FDB origin in 90% (9 of 10). In all 10 specimens, latex also covered the traversing first branch of the lateral plantar nerve (FBLPN, ie, Baxter nerve) between the FDB and quadratus plantae muscles. No latex was found in the plantar fat pad or plantar fascia in any specimen. Sonographically guided deep plantar fascia injections reliably deliver latex deep to the plantar fascia while avoiding intrafascial injection. However, the extent of direct plantar fascia contact is variable due to the intervening FDB. On the contrary, the traversing FBLPN is reliably covered by the injection. Deep plantar fascia injections may have a role in the management of refractory plantar fasciitis, particularly following failed superficial perifascial or intrafascial injections, in cases of preferential deep plantar fascia involvement, or when entrapment

  10. Effect of Gender on Mechanical Properties of the Plantar Fascia and Heel Fat Pad.

    PubMed

    Taş, Serkan

    2017-10-01

    The purpose of the study was to investigate the plantar fascia and heel fat pad stiffness and thickness parameters in females and compare these values with those of males. This study was carried out in 60 healthy sedentary participants (30 female, 30 male) between the ages of 19 and 50 years. Shear wave velocity (SWV) and thickness of the plantar fascia and heel fat pad were measured with an ultrasonography device. Males had a higher plantar fascia ( P = .037) and heel fat pad ( P = .001) thickness compared with females, but SWV of the plantar fascia ( P = .673), heel fat pad microchamber layer ( P = .240), and heel fat pad macrochamber layer ( P = .636) were similar in both groups. Body mass had a strong correlation with the plantar fascia ( r = 0.64, P < .001) and heel fat pad thickness ( r = 0.68, P < .001). Height had a moderate correlation with the plantar fascia ( r = 0.44, P < .001) and heel fat pad thickness ( r = 0.42, P = .001). Plantar fascia and heel fat pad stiffness were similar in both genders; however, females had a lower plantar fascia and heel fat pad thickness compared with males. Correlation analysis results suggest that higher plantar fascia and heel fat pad thickness in males may be related to higher body mass and height. Level III, Retrospective comparative study.

  11. Propeller torque load and propeller shaft torque response correlation during ice-propeller interaction

    NASA Astrophysics Data System (ADS)

    Polić, Dražen; Ehlers, Sören; Æsøy, Vilmar

    2017-03-01

    Ships use propulsion machinery systems to create directional thrust. Sailing in ice-covered waters involves the breaking of ice pieces and their submergence as the ship hull advances. Sometimes, submerged ice pieces interact with the propeller and cause irregular fluctuations of the torque load. As a result, the propeller and engine dynamics become imbalanced, and energy propagates through the propulsion machinery system until equilibrium is reached. In such imbalanced situations, the measured propeller shaft torque response is not equal to the propeller torque. Therefore, in this work, the overall system response is simulated under the ice-related torque load using the Bond graph model. The energy difference between the propeller and propeller shaft is estimated and related to their corresponding mechanical energy. Additionally, the mechanical energy is distributed among modes. Based on the distribution, kinetic and potential energy are important for the correlation between propeller torque and propeller shaft response.

  12. Self-oscillation in spin torque oscillator stabilized by field-like torque

    SciTech Connect

    Taniguchi, Tomohiro; Tsunegi, Sumito; Kubota, Hitoshi

    2014-04-14

    The effect of the field-like torque on the self-oscillation of the magnetization in spin torque oscillator with a perpendicularly magnetized free layer was studied theoretically. A stable self-oscillation at zero field is excited for negative β while the magnetization dynamics stops for β = 0 or β > 0, where β is the ratio between the spin torque and the field-like torque. The reason why only the negative β induces the self-oscillation was explained from the view point of the energy balance between the spin torque and the damping. The oscillation power and frequency for various β were also studied by numerical simulation.

  13. Efficient micromagnetic modelling of spin-transfer torque and spin-orbit torque

    NASA Astrophysics Data System (ADS)

    Abert, Claas; Bruckner, Florian; Vogler, Christoph; Suess, Dieter

    2018-05-01

    While the spin-diffusion model is considered one of the most complete and accurate tools for the description of spin transport and spin torque, its solution in the context of dynamical micromagnetic simulations is numerically expensive. We propose a procedure to retrieve the free parameters of a simple macro-spin like spin-torque model through the spin-diffusion model. In case of spin-transfer torque the simplified model complies with the model of Slonczewski. A similar model can be established for the description of spin-orbit torque. In both cases the spin-diffusion model enables the retrieval of free model parameters from the geometry and the material parameters of the system. Since these parameters usually have to be determined phenomenologically through experiments, the proposed method combines the strength of the diffusion model to resolve material parameters and geometry with the high performance of simple torque models.

  14. [Research progress of larger flexion gap than extension gap in total knee arthroplasty].

    PubMed

    Zhang, Weisong; Hao, Dingjun

    2017-05-01

    To summarize the progress of larger flexion gap than extension gap in total knee arthro-plasty (TKA). The domestic and foreign related literature about larger flexion gap than extension gap in TKA, and its impact factors, biomechanical and kinematic features, and clinical results were summarized. During TKA, to adjust the relations of flexion gap and extension gap is one of the key factors of successful operation. The biomechanical, kinematic, and clinical researches show that properly larger flexion gap than extension gap can improve both the postoperative knee range of motion and the satisfaction of patients, but does not affect the stability of the knee joint. However, there are also contrary findings. So adjustment of flexion gap and extension gap during TKA is still in dispute. Larger flexion gap than extension gap in TKA is a new joint space theory, and long-term clinical efficacy, operation skills, and related complications still need further study.

  15. Torque shudder protection device and method

    DOEpatents

    King, Robert D.; De Doncker, Rik W. A. A.; Szczesny, Paul M.

    1997-01-01

    A torque shudder protection device for an induction machine includes a flux command generator for supplying a steady state flux command and a torque shudder detector for supplying a status including a negative status to indicate a lack of torque shudder and a positive status to indicate a presence of torque shudder. A flux adapter uses the steady state flux command and the status to supply a present flux command identical to the steady state flux command for a negative status and different from the steady state flux command for a positive status. A limiter can receive the present flux command, prevent the present flux command from exceeding a predetermined maximum flux command magnitude, and supply the present flux command to a field oriented controller. After determining a critical electrical excitation frequency at which a torque shudder occurs for the induction machine, a flux adjuster can monitor the electrical excitation frequency of the induction machine and adjust a flux command to prevent the monitored electrical excitation frequency from reaching the critical electrical excitation frequency.

  16. Torque shudder protection device and method

    DOEpatents

    King, R.D.; Doncker, R.W.A.A. De.; Szczesny, P.M.

    1997-03-11

    A torque shudder protection device for an induction machine includes a flux command generator for supplying a steady state flux command and a torque shudder detector for supplying a status including a negative status to indicate a lack of torque shudder and a positive status to indicate a presence of torque shudder. A flux adapter uses the steady state flux command and the status to supply a present flux command identical to the steady state flux command for a negative status and different from the steady state flux command for a positive status. A limiter can receive the present flux command, prevent the present flux command from exceeding a predetermined maximum flux command magnitude, and supply the present flux command to a field oriented controller. After determining a critical electrical excitation frequency at which a torque shudder occurs for the induction machine, a flux adjuster can monitor the electrical excitation frequency of the induction machine and adjust a flux command to prevent the monitored electrical excitation frequency from reaching the critical electrical excitation frequency. 5 figs.

  17. Feasibility study for convertible engine torque converter

    NASA Technical Reports Server (NTRS)

    1985-01-01

    The feasibility study has shown that a dump/fill type torque converter has excellent potential for the convertible fan/shaft engine. The torque converter space requirement permits internal housing within the normal flow path of a turbofan engine at acceptable engine weight. The unit permits operating the engine in the turboshaft mode by decoupling the fan. To convert to turbofan mode, the torque converter overdrive capability bring the fan speed up to the power turbine speed to permit engagement of a mechanical lockup device when the shaft speed are synchronized. The conversion to turbofan mode can be made without drop of power turbine speed in less than 10 sec. Total thrust delivered to the aircraft by the proprotor, fan, and engine during tansient can be controlled to prevent loss of air speed or altitude. Heat rejection to the oil is low, and additional oil cooling capacity is not required. The turbofan engine aerodynamic design is basically uncompromised by convertibility and allows proper fan design for quiet and efficient cruise operation. Although the results of the feasibility study are exceedingly encouraging, it must be noted that they are based on extrapolation of limited existing data on torque converters. A component test program with three trial torque converter designs and concurrent computer modeling for fluid flow, stress, and dynamics, updated with test results from each unit, is recommended.

  18. Force, Torque and Stiffness: Interactions in Perceptual Discrimination

    PubMed Central

    Wu, Bing; Klatzky, Roberta L.; Hollis, Ralph L.

    2011-01-01

    Three experiments investigated whether force and torque cues interact in haptic discrimination of force, torque and stiffness, and if so, how. The statistical relation between force and torque was manipulated across four experimental conditions: Either one type of cue varied while the other was constant, or both varied so as to be positively correlated, negatively correlated, or uncorrelated. Experiment 1 showed that the subjects’ ability to discriminate force was improved by positively correlated torque but impaired with uncorrelated torque, as compared to the constant torque condition. Corresponding effects were found in Experiment 2 for the influence of force on torque discrimination. These findings indicate that force and torque are integrated in perception, rather than being processed as separate dimensions. A further experiment demonstrated facilitation of stiffness discrimination by correlated force and torque, whether the correlation was positive or negative. The findings suggest new means of augmenting haptic feedback to facilitate perception of the properties of soft objects. PMID:21359137

  19. Charge-induced spin torque in Weyl semimetals

    NASA Astrophysics Data System (ADS)

    Kurebayashi, Daichi; Nomura, Kentaro

    In this work, we present phenomenological and microscopic derivations of spin torques in magnetically doped Weyl semimetals. As a result, we obtain the analytical expression of the spin torque generated, without a flowing current, when the chemical potential is modulated. We also find that this spin torque is a direct consequence of the chiral anomaly. Therefore, observing this spin torque in magnetic Weyl semimetals might be an experimental evidence of the chiral anomaly. This spin torque has also a great advantage in application. In contrast to conventional current-induced spin torques such as the spin-transfer torques, this spin torque does not accompany a constant current flow. Thus, devices using this operating principle is free from the Joule heating and possibly have higher efficiency than devices using conventional current-induced spin torques. This work was supported by JSPS KAKENHI Grant Number JP15H05854 and JP26400308.

  20. Flexion relaxation of the hamstring muscles during lumbar-pelvic rhythm.

    PubMed

    Sihvonen, T

    1997-05-01

    This study investigated the simultaneous activity of back muscles and hamstring muscles during sagittal forward body flexion and extension in healthy persons. The study was cross-sectional. A descriptive study of paraspinal and hamstring muscle activity in normal persons during lumbar-pelvic rhythm. A university hospital. Forty healthy volunteers (21 men, 19 women, ages 17 to 48 years), all without back pain or other pain syndromes. Surface electromyography (EMG) was used to follow activities in the back and the hamstring muscles. With movement sensors, real lumbar flexion was separated from simultaneous pelvic motion by monitoring the components of motion with a two-inclinometer method continuously from the initial upright posture into full flexion. All signals were sampled during real-time monitoring for off-line analyses. Back muscle activity ceased (ie, flexion relaxation [FR] occurred) at lumbar flexion with a mean of 79 degrees. Hamstring activity lasted longer and EMG activity ceased in the hamstrings when nearly full lumbar flexion (97%) was reached. After this point total flexion and pelvic flexion continued further, so that the last part of lumbar flexion and the last part of pelvic flexion happened without back muscle activity or hamstring bracing, respectively. FR of the back muscles during body flexion has been well established and its clinical significance in low back pain has been confirmed. In this study, it was shown for the first time that the hip extensors (ie, hamstring muscles) relax during forward flexion but with different timing. FR in hamstrings is not dependent on or coupled firmly with back muscle behavior in spinal disorders and the lumbar pelvic rhythm can be locally and only partially disturbed.

  1. Quantification of muscle oxygenation and flow of healthy volunteers during cuff occlusion of arm and leg flexor muscles and plantar flexion exercise

    NASA Astrophysics Data System (ADS)

    Durduran, Turgut; Yu, Guoqiang; Zhou, Chao; Lech, Gwen; Chance, Britton; Yodh, Arjun G.

    2003-07-01

    A hybrid instrument combining near infrared and diffuse correlation spectroscopies was used to measure muscle oxygenation and blood flow dynamics during cuff occlusion and ischemia. Measurements were done on six healthy subjects on their arm and leg flexor muscles. Hemodynamic response was characterized for blood oxygen saturation, total hemoglobin concenration and relative blood flow speed. The characterization allowed us to define the normal response range as well as showing the feasibility of using a hybrid instrument for dynamic measurements.

  2. Determinants of shoulder and elbow flexion range: results from the San Antonio Longitudinal Study of Aging.

    PubMed

    Escalante, A; Lichtenstein, M J; Hazuda, H P

    1999-08-01

    To gain a knowledge of factors associated with impaired upper extremity range of motion (ROM) in order to understand pathways that lead to disability. Shoulder and elbow flexion range was measured in a cohort of 695 community-dwelling subjects aged 65 to 74 years. Associations between subjects' shoulder and elbow flexion ranges and their demographic and anthropometric characteristics, as well as the presence of diabetes mellitus or self-reported physician-diagnosed arthritis, were examined using multivariate regression models. The relationship between shoulder or elbow flexion range and subjects' functional reach was examined to explore the functional significance of ROM in these joints. The flexion range for the 4 joints studied was at least 120 degrees in nearly all subjects (> or = 99% of the subjects for each of the 4 joints). Multivariate models revealed significant associations between male sex, Mexican American ethnic background, the use of oral hypoglycemic drugs or insulin to treat diabetes mellitus, and a lower shoulder flexion range. A lower elbow flexion range was associated with male sex, increasing body mass index, and the use of oral hypoglycemic drugs or insulin. A higher shoulder or elbow flexion range was associated with a lower likelihood of having a short functional reach. The great majority of community-dwelling elderly have a flexion range of shoulder and elbow joints that can be considered functional. Diabetes mellitus and obesity are two potentially treatable factors associated with reduced flexion range of these two functionally important joints.

  3. Impact of Soft Tissue Imbalance on Knee Flexion Angle After Posterior Stabilized Total Knee Arthroplasty.

    PubMed

    Tsukada, Sachiyuki; Fujii, Tomoko; Wakui, Motohiro

    2017-08-01

    This study was performed to assess the impact of soft tissue imbalance on the knee flexion angle 2 years after posterior stabilized total knee arthroplasty (TKA). A total of 329 consecutive varus knees were included to assess the association of knee flexion angle 2 years after TKA with preoperative, intraoperative, and postoperative variables. All intraoperative soft tissue measurements were performed by a single surgeon under spinal anesthesia in a standardized manner including the subvastus approach, reduced patella, and without use of a pneumonic tourniquet. Multiple linear regression analysis showed no significant correlations in terms of intraoperative valgus imbalance at 90-degree flexion or the difference in soft tissue tension between 90-degree flexion and 0-degree extension (β = -0.039; 95% confidence interval [CI], -0.88 to 0.80; P = .93 and β = 0.015; 95% CI, -0.29 to 0.32; P = .92, respectively). Preoperative flexion angle was significantly correlated with knee flexion angle 2 years after TKA (β = 0.42; 95% CI, 0.33 to 0.51; P < .0001). Avoiding valgus imbalance at 90-degree flexion and aiming for strictly equal soft tissue tension between 90-degree flexion and 0-degree extension had little practical value with regard to knee flexion angle 2 years after posterior stabilized TKA. Copyright © 2017 The Author(s). Published by Elsevier Inc. All rights reserved.

  4. AX-5 space suit bearing torque investigation

    NASA Technical Reports Server (NTRS)

    Loewenthal, Stuart; Vykukal, Vic; Mackendrick, Robert; Culbertson, Philip, Jr.

    1990-01-01

    The symptoms and eventual resolution of a torque increase problem occurring with ball bearings in the joints of the AX-5 space suit are described. Starting torques that rose 5 to 10 times initial levels were observed in crew evaluation tests of the suit in a zero-g water tank. This bearing problem was identified as a blocking torque anomaly, observed previously in oscillatory gimbal bearings. A large matrix of lubricants, ball separator designs and materials were evaluated. None of these combinations showed sufficient tolerance to lubricant washout when repeatedly cycled in water. The problem was resolved by retrofitting a pressure compensated, water exclusion seal to the outboard side of the bearing cavity. The symptoms and possible remedies to blocking are discussed.

  5. RFID Torque Sensing Tag System for Fasteners

    NASA Technical Reports Server (NTRS)

    Fink, Patrick W. (Inventor); Lin, Gregory Y. (Inventor); Ngo, Phong H. (Inventor); Kennedy, Timothy F. (Inventor)

    2016-01-01

    The present invention provides an RFID-based torque sensor that can be used to quickly monitor off the shelf fasteners including fasteners that are used in expensive satellites or other uses where fastener failure can be very costly. In one embodiment, an antenna, RFID ring and spring comprise a sensor tag that can be interrogated with an interrogation signal produced by an interrogator device. When sufficient torque is applied to the fastener, an RFID circuit is connected, and produces a radio frequency (RF) signal that can be read by the interrogator. In one embodiment, the RFID circuit does not transmit when the spring member is not compressed, thereby indicating insufficient tensioning of the fastener. The present invention offers the ability to remotely, quickly, and inexpensively verify that any number of fasteners are torqued properly upon initial installation. Where applicable, the present invention allows low cost monitoring over the life of the fastener.

  6. Variable Torque Prescription: State of Art.

    PubMed Central

    Lacarbonara, Mariano; Accivile, Ettore; Abed, Maria R.; Dinoi, Maria Teresa; Monaco, Annalisa; Marzo, Giuseppe; Capogreco, Mario

    2015-01-01

    The variable prescription is widely described under the clinical aspect: the clinics is the result of the evolution of the state-of-the-art, aspect that is less considered in the daily literature. The state-of-the-art is the key to understand not only how we reach where we are but also to learn how to manage propely the torque, focusing on the technical and biomechanical purpos-es that led to the change of the torque values over time. The aim of this study is to update the clinicians on the aspects that affect the torque under the biomechanical sight, helping them to understand how to managing it, following the “timeline changes” in the different techniques so that the Variable Prescription Orthodontic (VPO) would be a suitable tool in every clinical case. PMID:25674173

  7. Cogging Torque Minimization in Transverse Flux Machines

    SciTech Connect

    Husain, Tausif; Hasan, Iftekhar; Sozer, Yilmaz

    2017-02-16

    This paper presents the design considerations in cogging torque minimization in two types of transverse flux machines. The machines have a double stator-single rotor configuration with flux concentrating ferrite magnets. One of the machines has pole windings across each leg of an E-Core stator. Another machine has quasi-U-shaped stator cores and a ring winding. The flux in the stator back iron is transverse in both machines. Different methods of cogging torque minimization are investigated. Key methods of cogging torque minimization are identified and used as design variables for optimization using a design of experiments (DOE) based on the Taguchi method.more » A three-level DOE is performed to reach an optimum solution with minimum simulations. Finite element analysis is used to study the different effects. Two prototypes are being fabricated for experimental verification.« less

  8. Atmospheric Gravitational Torque Variations Based on Various Gravity Fields

    NASA Technical Reports Server (NTRS)

    Sanchez, Braulio V.; Rowlands, David; Smith, David E. (Technical Monitor)

    2001-01-01

    Advancements in the study of the Earth's variable rate of rotation and the motion of its rotation axis have given impetus to the analysis of the torques between the atmosphere, oceans and solid Earth. The output from global general circulation models of the atmosphere (pressure, surface stress) is being used as input to the torque computations. Gravitational torque between the atmosphere, oceans and solid Earth is an important component of the torque budget. Computation of the gravitational torque involves the adoption of a gravitational model from a wide variety available. The purpose of this investigation is to ascertain to what extent this choice might influence the results of gravitational torque computations.

  9. Calcaneal attachment of the plantar fascia: MR findings in asymptomatic volunteers.

    PubMed

    Ehrmann, Christine; Maier, Matthias; Mengiardi, Bernard; Pfirrmann, Christian W A; Sutter, Reto

    2014-09-01

    To determine the spectrum of magnetic resonance (MR) imaging findings at the calcaneal attachment of the plantar fascia in asymptomatic volunteers. The study was approved by the institutional review board, and informed consent was obtained from all subjects. MR imaging was performed in 77 asymptomatic volunteers (mean age, 48.0 years; age range, 23-83 years) with use of a 1.5-T system. There were 40 women (mean age, 49.0 years; age range, 24-83 years) and 37 men (mean age, 48.0 years; age range, 23-83 years). Signal intensity characteristics and thickness of the medial, central, and lateral fascicles of the plantar fascia were assessed independently by two radiologists. The presence of soft-tissue edema, bone marrow edema, and bone spur formation at the attachment of the plantar fascia was noted. Datasets were analyzed with inferential statistic procedures. The mean thickness of the plantar fascia was 0.6 mm (medial fascicle), 4.0 mm (central fascicle), and 2.3 mm (lateral fascicle). Increased signal intensity in the plantar fascia was seen with the T1-weighted sequence in 16 of the 77 volunteers (21%), the T2-weighted sequence in six (7.8%), and the short inversion time inversion-recovery sequence in six (7.8%). Soft-tissue edema was seen deep to the plantar fascia in five of the 77 volunteers (6.5%) and superficial to the plantar fascia in 16 (21%). A calcaneal spur was detected in 15 of the 77 volunteers (19%). Calcaneal bone marrow edema was present in four volunteers (5.2%). T1-weighted signal intensity changes in the plantar fascia, soft-tissue edema superficial to the plantar fascia, and calcaneal spurs are common findings in asymptomatic volunteers and should be used with caution in the diagnosis of plantar fasciitis. Increased signal intensity within the plantar fascia with fluid-sensitive sequences is uncommon in asymptomatic volunteers.

  10. Torque limit of PM motors for field-weakening region operation

    DOEpatents

    Royak, Semyon [Beachwood, OH; Harbaugh, Mark M [Richfield, OH

    2012-02-14

    The invention includes a motor controller and technique for controlling a permanent magnet motor. In accordance with one aspect of the present technique, a permanent magnet motor is controlled by receiving a torque command, determining a physical torque limit based on a stator frequency, determining a theoretical torque limit based on a maximum available voltage and motor inductance ratio, and limiting the torque command to the smaller of the physical torque limit and the theoretical torque limit. Receiving the torque command may include normalizing the torque command to obtain a normalized torque command, determining the physical torque limit may include determining a normalized physical torque limit, determining a theoretical torque limit may include determining a normalized theoretical torque limit, and limiting the torque command may include limiting the normalized torque command to the smaller of the normalized physical torque limit and the normalized theoretical torque limit.

  11. Motor impairments related to brain injury timing in early hemiparesis. Part II: abnormal upper extremity joint torque synergies.

    PubMed

    Sukal-Moulton, Theresa; Krosschell, Kristin J; Gaebler-Spira, Deborah J; Dewald, Julius P A

    2014-01-01

    Extensive neuromotor development occurs early in human life, and the timing of brain injury may affect the resulting motor impairment. In Part I of this series, it was demonstrated that the distribution of weakness in the upper extremity depended on the timing of brain injury in individuals with childhood-onset hemiparesis. The goal of this study was to characterize how timing of brain injury affects joint torque synergies, or losses of independent joint control. Twenty-four individuals with hemiparesis were divided into 3 groups based on the timing of their injury: before birth (PRE-natal, n = 8), around the time of birth (PERI-natal, n = 8), and after 6 months of age (POST-natal, n = 8). Individuals with hemiparesis and 8 typically developing peers participated in maximal isometric shoulder, elbow, wrist, and finger torque generation tasks while their efforts were recorded by a multiple degree-of-freedom load cell. Motor output in 4 joints of the upper extremity was concurrently measured during 8 primary torque generation tasks to quantify joint torque synergies. There were a number of significant coupling patterns identified in individuals with hemiparesis that differed from the typically developing group. POST-natal differences were most noted in the coupling of shoulder abductors with elbow, wrist, and finger flexors, while the PRE-natal group demonstrated significant distal joint coupling with elbow flexion. The torque synergies measured provide indirect evidence for the use of bulbospinal pathways in the POST-natal group, while those with earlier injury may use relatively preserved ipsilateral corticospinal motor pathways.

  12. Assessment of finger forces and wrist torques for functional grasp using new multichannel textile neuroprostheses.

    PubMed

    Lawrence, Marc; Gross, Gion-Pitschen; Lang, Martin; Kuhn, Andreas; Keller, Thierry; Morari, Manfred

    2008-08-01

    New multichannel textile neuroprotheses were developed, which comprise multiple sets of transcutaneous electrode arrays and connecting wires embroidered into a fabric layer. The electrode arrays were placed on the forearm above the extrinsic finger flexors and extensors. Activation regions for selective finger flexion and wrist extension were configured by switching a subset of the array elements between cathode, anode, and off states. We present a new isometric measurement system for the assessment of finger forces and wrist torques generated using the new neuroprostheses. Finger forces (from the middle phalanxes) were recorded using five load cells mounted on a "grasp handle" that can be arbitrarily positioned in space. The hand and the grasp handle were rigidly mounted to a 6-degree of freedom load cell, and the forces and torques about the wrist were recorded. A vacuum cushion was used to comfortably fixate the forearm. The position and orientation of the forearm, wrist, fingers, and handle were recorded using a new three-dimensional position measurement system (accuracy <+/-1 mm). The measurement system was integrated into the real-time multichannel transcutaneous electrode environment, which is able to control the spatiotemporal position of multiple activation regions. Using the combined system and textile neuroprosthesis, we were able to optimize the activation regions to produce selective finger and wrist articulation, enabling improved functional grasp.

  13. The influence of muscles on knee flexion during the swing phase of gait.

    PubMed

    Piazza, S J; Delp, S L

    1996-06-01

    Although the movement of the leg during swing phase is often compared to the unforced motion of a compound pendulum, the muscles of the leg are active during swing and presumably influence its motion. To examine the roles of muscles in determining swing phase knee flexion, we developed a muscle-actuated forward dynamic simulation of the swing phase of normal gait. Joint angles and angular velocities at toe-off were derived from experimental measurements, as were pelvis motions and muscle excitations. Joint angles and joint moments resulting from the simulation corresponded to experimental measurements made during normal gait. Muscular joint moments and initial joint angular velocities were altered to determine the effects of each upon peak knee flexion in swing phase. As expected, the simulation demonstrated that either increasing knee extension moment or decreasing toe-off knee flexion velocity decreased peak knee flexion. Decreasing hip flexion moment or increasing toe-off hip flexion velocity also caused substantial decreases in peak knee flexion. The rectus femoris muscle played an important role in regulating knee flexion; removal of the rectus femoris actuator from the model resulted in hyperflexion of the knee, whereas an increase in the excitation input to the rectus femoris actuator reduced knee flexion. These findings confirm that reduced knee flexion during the swing phase (stiff-knee gait) may be caused by overactivity of the rectus femoris. The simulations also suggest that weakened hip flexors and stance phase factors that determine the angular velocities of the knee and hip at toe-off may be responsible for decreased knee flexion during swing phase.

  14. Navigation-based femorotibial rotation pattern correlated with flexion angle after total knee arthroplasty.

    PubMed

    Ishida, Kazunari; Shibanuma, Nao; Matsumoto, Tomoyuki; Sasaki, Hiroshi; Takayama, Koji; Matsuzaki, Tokio; Tei, Katsumasa; Kuroda, Ryosuke; Kurosaka, Masahiro

    2016-01-01

    To investigate whether intraoperative kinematics obtained by navigation systems can be divided into several kinematic patterns and to assess the correlation between the intraoperative kinematics with maximum flexion angles before and after total knee arthroplasty (TKA). Fifty-four posterior-stabilised (PS) TKA implanted using an image-free navigation system were evaluated. At registration and after implantation, tibial internal rotation angles at maximum extension, 30°, 45°, 60°, 90°, and maximum flexion were collected. The rotational patterns were divided into four groups and were examined the correlation with maximum flexion before and after operation. Tibial internal rotation from 90° of flexion to maximum flexion at registration was correlated with maximum flexion angles pre- and postoperatively. The four groups showed statistically different kinematic patterns. The group with tibial external rotation up to 90° of flexion, following tibial internal rotation at registration, achieved better flexion angles, compared to those of another groups (126.7° ± 12.0°, p < 0.05). The group with tibial external rotation showed the worst flexion angles (80.0° ± 40.4°, p < 0.05). Furthermore, the group with limited extension showed worse flexion angles (111.6° ± 8.9°, p < 0.05). Navigation-based kinematic patterns found at registration predict postoperative maximum flexion angle in PS TKA. Navigation-based kinematics can be useful information during TKA surgery. Diagnostic studies, development of diagnostic criteria in a consecutive series of patients and a universally applied "gold" standard, Level II.

  15. The prevalence of increased proximal junctional flexion following posterior instrumentation and arthrodesis for adolescent idiopathic scoliosis.

    PubMed

    Hollenbeck, S Matt; Glattes, R Christopher; Asher, Marc A; Lai, Sue Min; Burton, Douglas C

    2008-07-01

    Retrospective case series. To determine the prevalence of proximal junctional sagittal plane flexion increase after posterior instrumentation and arthrodesis. Increased flexion proximal to the junction of the instrumented and fused spinal region with the adjacent mobile spine seems to be a relatively recent observation, may be increasing, and is occasionally problematic. The proximal junctional sagittal angulation 2 motion segments above the upper end instrumentation levels was measured on lateral standing preoperative and follow-up radiographs. One hundred seventy-four of 208 consecutive patients (84%) at an average radiograph follow-up of 4.9 +/- 2.73 years had increased proximal junctional flexion in 9.2%. The preoperative junctional measurements were normal for both normal and increased flexion groups. At follow-up, proximal junctional flexion had increased significantly more in the increased flexion group (2.1 degrees vs. 14.1 degrees , P < 0.0001). None of the possible risk factors studied, including demographic comparisons, Lenke classification (including lumbar and sagittal modifiers), end-instrumented vertebrae, end vertebra anchor configurations, surgical sequence, additional anterior surgery, rib osteotomies, and instrumentation length, were significantly associated with increased proximal junctional flexion at follow-up. Lenke 6 curves were at marginal risk of increased proximal junctional flexion (P = 0.0108). There were no differences between the groups in total Scoliosis Research Society-22r scores at an average follow-up of 8.0 +/- 3.74 years. No patient had additional surgery related to increased proximal junctional flexion. The prevalence of increased proximal junctional flexion was 9.2%. No significant risk factors were identified. Total Scoliosis Research Society-22r scores were similar for groups with normal and increased proximal junctional flexion at follow-up.

  16. Peak torque and muscle balance in the knees of young U-15 and U-17 soccer athletes playing various tactical positions.

    PubMed

    Chiamonti Bona, Cleiton; Tourinho Filho, Hugo; Izquierdo, Mikel; Pires Ferraz, Ricardo M; Marques, Mário C

    2017-01-01

    Soccer is a sport that is practiced worldwide and has been investigated in its various aspects, particularly muscle strength, which is an essential motor skill for sports performance. The objective of this study was to investigate the peak torque and muscle balance on the knee extensor and flexor of young soccer players in the tactical positions of goalkeeper, defender, full back, midfielder, defensive midfielder and striker, as well as to determine which field position has the highest peak torque. Forty-nine male players were recruited and divided into two categories during the preparatory period of the season: the Under-15 (U-15) group (N.=23, mean age 14.7±0.5 years, body mass 58.2±10.5 kg, body height 168.5±7.6 cm), and the Under-17 (U-17) group (N.=26, mean age 16.8±0.4 years, body mass 69.2±7.9 kg, body height 176.2±6.6 cm). The U-17 athletes presented a higher peak torque in all the movements of flexion and extension in the two angular velocities (i.e. 60°/s and 300°/s), but only the dominant knee extensor at 300°/s was significantly different between the two categories as well as the percentage change in peak torque compared between U-15 and U-17 was always above 20%. The peak torque variation in the U-17 category (i.e. mostly above 20%) highlights a higher peak torque compared to U-15 athletes. The muscular deficit of the two categories presented a low average of 10-15%, indicating a good muscle balance between knee extensors and flexors. Finally, goalkeepers and defenders achieved the highest peak torque amongst the field positions.

  17. Reproducibility of sonographic measurement of thickness and echogenicity of the plantar fascia.

    PubMed

    Cheng, Ju-Wen; Tsai, Wen-Chung; Yu, Tung-Yang; Huang, Kuo-Yao

    2012-01-01

    To evaluate the intra- and interrater reliability of ultrasonographic measurements of the thickness and echogenicity of the plantar fascia. Eleven patients (20 feet), who complained of inferior heel pain, and 26 volunteers (52 feet) were enrolled. Two sonographers independently imaged the plantar fascia in both longitudinal and transverse planes. Volunteers were assessed twice to evaluate intrarater reliability. Quantitative evaluation of the echogenicity of the plantar fascia was performed by measuring the mean gray level of the region of interest using Digital Imaging and Communications in Medicine viewer software. Sonographic evaluation of the thickness of the plantar fascia showed high reliability. Sonographic evaluations of the presence or absence of hypoechoic change in the plantar fascia showed surprisingly low agreement. The reliability of gray-scale evaluations appears to be much better than subjective judgments in the evaluation of echogenicity. Transverse scanning did not show any advantage in sonographic evaluation of the plantar fascia. The reliability of sonographic examination of the thickness of the plantar fascia is high. Mean gray-level analysis of quantitative sonography can be used for the evaluation of echogenicity, which could reduce discrepancies in the interpretation of echogenicity by different sonographers. Longitudinal instead of transverse scanning is recommended for imaging the plantar fascia. Copyright © 2011 Wiley Periodicals, Inc.

  18. Rearfoot eversion has indirect effects on plantar fascia tension by changing the amount of arch collapse.

    PubMed

    Lee, Sae Yong; Hertel, Jay; Lee, Sung Cheol

    2010-01-01

    Rearfoot eversion motion and arch height are believed to contribute to increased tension on the plantar fascia and arch collapse during gait but the specifics of these relationships are not clear. To examine the relationships among static arch height, rearfoot eversion, dynamic arch height, and plantar fascia tension. 28 healthy males participated. After static arch height was measured, the subjects were asked to run at 4.5m/s while frontal plane rearfoot motion, dynamic arch height, and ground reaction forces were collected. The relationships among variables were examined with bivariate correlations and path analysis. The results indicated a high correlation between dynamic arch height and static arch height (r=0.642), plantar fascia tension (r=-0.797), and maximum rearfoot eversion motion during gait (r=-0.518). The path analysis model without the direct rearfoot eversion effect explained 81.2% of the variance in plantar fascia tension, while the model with the direct rearfoot eversion effect explained 82.1% of the variance in plantar fascia tension. Including the indirect effect of maximum rearfoot eversion motion on plantar fascia tension through control of dynamic arch height is the model that best explains the interrelationships of these foot characteristics. The amount of maximum rearfoot eversion motion itself is not a good predictor of plantar fascia tension, however, together with the arch height, maximum rearfoot eversion motion is a good predictor because it has a pronounced indirect effect on plantar fascia tension. Copyright 2010. Published by Elsevier Ltd.

  19. Finite element modelling of Plantar Fascia response during running on different surface types

    NASA Astrophysics Data System (ADS)

    Razak, A. H. A.; Basaruddin, K. S.; Salleh, A. F.; Rusli, W. M. R.; Hashim, M. S. M.; Daud, R.

    2017-10-01

    Plantar fascia is a ligament found in human foot structure located beneath the skin of human foot that functioning to stabilize longitudinal arch of human foot during standing and normal gait. To perform direct experiment on plantar fascia seems very difficult since the structure located underneath the soft tissue. The aim of this study is to develop a finite element (FE) model of foot with plantar fascia and investigate the effect of the surface hardness on biomechanical response of plantar fascia during running. The plantar fascia model was developed using Solidworks 2015 according to the bone structure of foot model that was obtained from Turbosquid database. Boundary conditions were set out based on the data obtained from experiment of ground reaction force response during running on different surface hardness. The finite element analysis was performed using Ansys 14. The results found that the peak of stress and strain distribution were occur on the insertion of plantar fascia to bone especially on calcaneal area. Plantar fascia became stiffer with increment of Young’s modulus value and was able to resist more loads. Strain of plantar fascia was decreased when Young’s modulus increased with the same amount of loading.

  20. 40 CFR 1065.310 - Torque calibration.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... force is measured. The lever arm must be perpendicular to gravity (i.e., horizontal), and it must be... known distance along a lever arm. Make sure the weights' lever arm is perpendicular to gravity (i.e... Earth's gravity, as described in § 1065.630. Calculate the reference torque as the weights' reference...

  1. A New Twist on Torque Labs

    ERIC Educational Resources Information Center

    Lane, W. Brian

    2014-01-01

    The traditional introductory-level meterstick-balancing lab assumes that students already know what torque is and that they readily identify it as a physical quantity of interest. We propose a modified version of this activity in which students qualitatively and quantitatively measure the amount of force required to keep the meterstick level. The…

  2. Anatomy of a bearing torque problem

    NASA Technical Reports Server (NTRS)

    Phinney, Damon D.

    1987-01-01

    In the early 1970s, an antenna despin drive was developed for MBB solar science satellite HELIOS. A problem with high bearing drag torque that was encountered on the two flight models of this drive, after successful tests were completed on twelve bearings, an engineering model, and the qualification unit is discussed.

  3. Torque-balanced vibrationless rotary coupling

    DOEpatents

    Miller, Donald M.

    1980-01-01

    This disclosure describes a torque-balanced vibrationless rotary coupling for transmitting rotary motion without unwanted vibration into the spindle of a machine tool. A drive member drives a driven member using flexible connecting loops which are connected tangentially and at diametrically opposite connecting points through a free floating ring.

  4. Computing the motor torque of Escherichia coli.

    PubMed

    Das, Debasish; Lauga, Eric

    2018-06-13

    The rotary motor of bacteria is a natural nano-technological marvel that enables cell locomotion by powering the rotation of semi-rigid helical flagellar filaments in fluid environments. It is well known that the motor operates essentially at constant torque in counter-clockwise direction but past work have reported a large range of values of this torque. Focusing on Escherichia coli cells that are swimming and cells that are stuck on a glass surface for which all geometrical and environmental parameters are known (N. C. Darnton et al., J. Bacteriol., 2007, 189, 1756-1764), we use two validated numerical methods to compute the value of the motor torque consistent with experiments. Specifically, we use (and compare) a numerical method based on the boundary integral representation of Stokes flow and also develop a hybrid method combining boundary element and slender body theory to model the cell body and flagellar filament, respectively. Using measured rotation speed of the motor, our computations predict a value of the motor torque in the range 440 pN nm to 829 pN nm, depending critically on the distance between the flagellar filaments and the nearby surface.

  5. 40 CFR 1065.310 - Torque calibration.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... maintenance. Use good engineering judgment to repeat the calibration. Follow the torque transducer... the U.S. National Oceanographic and Atmospheric Administration's surface gravity prediction Web site at http://www.ngs.noaa.gov/cgi-bin/grav_pdx.prl. If this Web site is unavailable, you may use the...

  6. 40 CFR 1065.310 - Torque calibration.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... maintenance. Use good engineering judgment to repeat the calibration. Follow the torque transducer... the U.S. National Oceanographic and Atmospheric Administration's surface gravity prediction Web site at http://www.ngs.noaa.gov/cgi-bin/grav_pdx.prl. If this Web site is unavailable, you may use the...

  7. Torque wrench allows readings from inaccessible locations

    NASA Technical Reports Server (NTRS)

    De Barnardo, M.

    1966-01-01

    Torque wrench with an adjustable drive shaft permits indicator to remain in view when used on sections of equipment with limited access. The shaft is capable of protruding from either side of the wrench head by means of spring loaded balls.

  8. Alignment of Irregular Grains by Mechanical Torques

    NASA Astrophysics Data System (ADS)

    Hoang, Thiem; Cho, Jungyeon; Lazarian, A.

    2018-01-01

    We study the alignment of irregular dust grains by mechanical torques due to the drift of grains through the ambient gas. We first calculate mechanical alignment torques (MATs) resulting from specular reflection of gas atoms for seven irregular shapes: one shape of mirror symmetry, three highly irregular shapes (HIS), and three weakly irregular shapes (WIS). We find that the grain with mirror symmetry experiences negligible MATs due to its mirror-symmetry geometry. Three HIS can produce strong MATs, which exhibit some generic properties as radiative torques (RATs), while three WIS produce less efficient MATs. We then study grain alignment by MATs for the different angles between the drift velocity and the ambient magnetic field, for paramagnetic and superparamagnetic grains assuming efficient internal relaxation. We find that for HIS grains, MATs can align subsonically drifting grains in the same way as RATs, with low-J and high-J attractors. For supersonic drift, MATs can align grains with low-J and high-J attractors, analogous to RAT alignment by anisotropic radiation. We also show that the joint action of MATs and magnetic torques in grains with iron inclusions can lead to perfect MAT alignment. Our results point out the potential importance of MAT alignment for HIS grains predicted by the analytical model of Lazarian & Hoang, although more theoretical and observational studies are required due to uncertainty in the shape of interstellar grains. We outline astrophysical environments where MAT alignment is potentially important.

  9. Nonambipolar Transport and Torque in Perturbed Equilibria

    NASA Astrophysics Data System (ADS)

    Logan, N. C.; Park, J.-K.; Wang, Z. R.; Berkery, J. W.; Kim, K.; Menard, J. E.

    2013-10-01

    A new Perturbed Equilibrium Nonambipolar Transport (PENT) code has been developed to calculate the neoclassical toroidal torque from radial current composed of both passing and trapped particles in perturbed equilibria. This presentation outlines the physics approach used in the development of the PENT code, with emphasis on the effects of retaining general aspect-ratio geometric effects. First, nonambipolar transport coefficients and corresponding neoclassical toroidal viscous (NTV) torque in perturbed equilibria are re-derived from the first order gyro-drift-kinetic equation in the ``combined-NTV'' PENT formalism. The equivalence of NTV torque and change in potential energy due to kinetic effects [J-K. Park, Phys. Plas., 2011] is then used to showcase computational challenges shared between PENT and stability codes MISK and MARS-K. Extensive comparisons to a reduced model, which makes numerous large aspect ratio approximations, are used throughout to emphasize geometry dependent physics such as pitch angle resonances. These applications make extensive use of the PENT code's native interfacing with the Ideal Perturbed Equilibrium Code (IPEC), and the combination of these codes is a key step towards an iterative solver for self-consistent perturbed equilibrium torque. Supported by US DOE contract #DE-AC02-09CH11466 and the DOE Office of Science Graduate Fellowship administered by the Oak Ridge Institute for Science & Education under contract #DE-AC05-06OR23100.

  10. Planetary Torque in 3D Isentropic Disks

    NASA Astrophysics Data System (ADS)

    Fung, Jeffrey; Masset, Frédéric; Lega, Elena; Velasco, David

    2017-03-01

    Planetary migration is inherently a three-dimensional (3D) problem, because Earth-size planetary cores are deeply embedded in protoplanetary disks. Simulations of these 3D disks remain challenging due to the steep resolution requirements. Using two different hydrodynamics codes, FARGO3D and PEnGUIn, we simulate disk-planet interaction for a one to five Earth-mass planet embedded in an isentropic disk. We measure the torque on the planet and ensure that the measurements are converged both in resolution and between the two codes. We find that the torque is independent of the smoothing length of the planet’s potential (r s), and that it has a weak dependence on the adiabatic index of the gaseous disk (γ). The torque values correspond to an inward migration rate qualitatively similar to previous linear calculations. We perform additional simulations with explicit radiative transfer using FARGOCA, and again find agreement between 3D simulations and existing torque formulae. We also present the flow pattern around the planets that show active flow is present within the planet’s Hill sphere, and meridional vortices are shed downstream. The vertical flow speed near the planet is faster for a smaller r s or γ, up to supersonic speeds for the smallest r s and γ in our study.

  11. Noncontact Measurements Of Torques In Shafts

    NASA Technical Reports Server (NTRS)

    Schwartzbart, Aaron

    1991-01-01

    Additional information extracted from eddy-current proximeter. Positioned over rotating shaft, measures both displacement of and torsion in shaft. Torque applied to shaft calculable from output of proximeter. Possible to extract torsion information from existing tape-recorded proximeter data.

  12. Torque Limits for Fasteners in Composites

    NASA Technical Reports Server (NTRS)

    Zhao, Yi

    2002-01-01

    The two major classes of laminate joints are bonded and bolted. Often the two classes are combined as bonded-bolted joints. Several characteristics of fiber reinforced composite materials render them more susceptible to joint problems than conventional metals. These characteristics include weakness in in-plane shear, transverse tension/compression, interlaminar shear, and bearing strength relative to the strength and stiffness in the fiber direction. Studies on bolted joints of composite materials have been focused on joining assembly subject to in-plane loads. Modes of failure under these loading conditions are net-tension failure, cleavage tension failure, shear-out failure, bearing failure, etc. Although the studies of torque load can be found in literature, they mainly discussed the effect of the torque load on in-plane strength. Existing methods for calculating torque limit for a mechanical fastener do not consider connecting members. The concern that a composite member could be crushed by a preload inspired the initiation of this study. The purpose is to develop a fundamental knowledge base on how to determine a torque limit when a composite member is taken into account. Two simplified analytical models were used: a stress failure analysis model based on maximum stress criterion, and a strain failure analysis model based on maximum strain criterion.

  13. Design and Test of a Soft Plantar Force Measurement System for Gait Detection

    PubMed Central

    Zhang, Xuefeng; Zhao, Yulong; Duan, Zhengyong; Liu, Yan

    2012-01-01

    This work describes a plantar force measurement system. The MEMS pressure sensor, as the key sensing element, is designed, fabricated and embedded into a flexible silicon oil-filled bladder made of silicon rubber to constitute a single sensing unit. A conditioning circuit is designed for signal processing and data acquisition. The characteristics of the plantar force sensing unit are investigated by both static and dynamic tests. A comparison of characteristics between the proposed plantar force sensing unit and a commercial flexible force sensor is presented. A practical experiment of plantar force measurement has been carried out to validate the system. The results demonstrate that the proposed measurement system has a potential for success in the application of plantar force measurement during normal gait. PMID:23208558

  14. Imaging of plantar fascia and Achilles injuries undertaken at the London 2012 Olympics.

    PubMed

    Elias, David A; Carne, Andrew; Bethapudi, Sarath; Engebretsen, Lars; Budgett, Richard; O'Connor, Philip

    2013-12-01

    Plantar fascia and distal Achilles injuries are common in elite athletes. Acute athletic injuries of the plantar fascia include acute plantar fasciopathy and partial or complete tears. Underlying most acute injuries is a background of underlying chronic plantar fasciopathy. Injuries may affect the central or less commonly lateral portions of the fascia and acute tears are generally proximal. Athletic Achilles injuries may occur at the mid tendon or the distal insertion, and there may be an underlying chronic tendinopathy. Acute or chronic paratendinopathy may occur as a separate entity or combined with Achilles injury. In this article, the spectrum of athletic injuries of the plantar fascia and Achilles is described, illustrated by imaging findings from the London 2012 Olympic games.

  15. Prediction of plantar shear stress distribution by artificial intelligence methods.

    PubMed

    Yavuz, Metin; Ocak, Hasan; Hetherington, Vincent J; Davis, Brian L

    2009-09-01

    Shear forces under the human foot are thought to be responsible for various foot pathologies such as diabetic plantar ulcers and athletic blisters. Frictional shear forces might also play a role in the metatarsalgia observed among hallux valgus (HaV) and rheumatoid arthritis (RA) patients. Due to the absence of commercial devices capable of measuring shear stress distribution, a number of linear models were developed. All of these have met with limited success. This study used nonlinear methods, specifically neural network and fuzzy logic schemes, to predict the distribution of plantar shear forces based on vertical loading parameters. In total, 73 subjects were recruited; 17 had diabetic neuropathy, 14 had HaV, 9 had RA, 11 had frequent foot blisters, and 22 were healthy. A feed-forward neural network (NN) and adaptive neurofuzzy inference system (NFIS) were built. These systems were then applied to a custom-built platform, which collected plantar pressure and shear stress data as subjects walked over the device. The inputs to both models were peak pressure, peak pressure-time integral, and time to peak pressure, and the output was peak resultant shear. Root-mean-square error (RMSE) values were calculated to test the models' accuracy. RMSE/actual shear ratio varied between 0.27 and 0.40 for NN predictions. Similarly, NFIS estimations resulted in a 0.28-0.37 ratio for local peak values in all subject groups. On the other hand, error percentages for global peak shear values were found to be in the range 11.4-44.1. These results indicate that there is no direct relationship between pressure and shear magnitudes. Future research should aim to decrease error levels by introducing shear stress dependent variables into the models.

  16. Superficial plantar cutaneous sensation does not trigger barefoot running adaptations.

    PubMed

    Thompson, M A; Hoffman, K M

    2017-09-01

    It has long been proposed that the gait alterations associated with barefoot running are mediated by alterations in sensory feedback, yet there has been no data to support this claim. Thus, the purpose of this study was to examine the role of superficial plantar cutaneous feedback in barefoot and shod running. 10 healthy active subjects (6 male, 4 female); mass: 65.2+9.7kg; age: 27+7.1years participated in this study. 10 over-ground running trials were completed in each of the following conditions: barefoot (BF), shod (SHOD), anesthetized barefoot (ANEST BF) and anesthetized shod (ANEST SHOD). For the anesthetized conditions 0.1-0.3mL of 1% lidocaine was injected into the dermal layer of the plantar foot below the metatarsal heads, lateral column and heel. 3-dimensional motion analysis and ground reaction force (GRF) data were captured as subjects ran over a 20m runway with a force plate at 12m. Kinematic and kinetic differences were analyzed via two-way repeated measure ANOVAs. The differences in gait between the BF and SHOD conditions were consistent with previous research, with subjects exhibiting a significant decrease in stride length and changing from rearfoot strike when SHOD to fore/midfoot strike when BF. Additionally, BF running was associated with decreased impact peak magnitudes and peak vertical GRFs. Despite anesthetizing the plantar surface, there was no difference between the BF and ANEST BF conditions in terms of stride length, foot strike or GRFs. Superficial cutaneous sensory receptors are not primarily responsible for the gait changes associated with barefoot running. Copyright © 2017 Elsevier B.V. All rights reserved.

  17. Anteroposterior translation does not correlate with knee flexion after total knee arthroplasty.

    PubMed

    Ishii, Yoshinori; Noguchi, Hideo; Takeda, Mitsuhiro; Sato, Junko; Toyabe, Shin-ichi

    2014-02-01

    Stiffness after a TKA can cause patient dissatisfaction and diminished function, therefore it is important to characterize predictors of ROM after TKA. Studies of AP translation in conscious individuals disagree whether AP translation affects maximum knee flexion angle after implantation of a highly congruent sphere and trough geometry PCL-substituting prosthesis in a TKA. We investigated whether AP translation correlated with maximum knee flexion angle (1) in patients who were awake, and (2) who were under anesthesia (to minimize the effects of voluntary muscle contraction) in a TKA with implantation of a PCL-substituting mobile-bearing prosthesis. AP translation was examined under both conditions in 34 primary TKAs. Measurements under anesthesia were performed when the patients were having anesthesia for a contralateral TKA. Awake measurements were made within 4 days of that anesthetic session in patients who had no residual sedative effects. The average postoperative interval for the index TKA flexion measurements was 23 months (range, 6-114 months). AP translation was evaluated at 75° flexion using an arthrometer. There was no correlation between postoperative maximum knee flexion and AP translation at 75° during consciousness. There was no correlation between postoperative maximum knee flexion and AP translation under anesthesia. AP translation at 75° flexion did not correlate with postoperative maximum knee flexion in either awake or anesthetized patients during a TKA with implantation of a posterior cruciate-substituting prosthesis.

  18. 49 CFR 572.165 - Upper and lower torso assemblies and torso flexion test procedure.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 49 Transportation 7 2012-10-01 2012-10-01 false Upper and lower torso assemblies and torso flexion... assemblies and torso flexion test procedure. (a) Upper/lower torso assembly. The test objective is to... (specified in 49 CFR 572.125(a)), on resistance to articulation between the upper torso assembly (drawing 167...

  19. 49 CFR 572.165 - Upper and lower torso assemblies and torso flexion test procedure.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 49 Transportation 7 2013-10-01 2013-10-01 false Upper and lower torso assemblies and torso flexion... assemblies and torso flexion test procedure. (a) Upper/lower torso assembly. The test objective is to... (specified in 49 CFR 572.125(a)), on resistance to articulation between the upper torso assembly (drawing 167...

  20. 49 CFR 572.135 - Upper and lower torso assemblies and torso flexion test procedure.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 49 Transportation 7 2014-10-01 2014-10-01 false Upper and lower torso assemblies and torso flexion... torso assemblies and torso flexion test procedure. (a) Upper/lower torso assembly. The test objective is... (drawing 880105-434), on resistance to articulation between the upper torso assembly (drawing 880105-300...

  1. 49 CFR 572.145 - Upper and lower torso assemblies and torso flexion test procedure.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 49 Transportation 7 2012-10-01 2012-10-01 false Upper and lower torso assemblies and torso flexion... assemblies and torso flexion test procedure. (a) The test objective is to determine the resistance of the... upper and lower halves of the torso assembly (refer to § 572.140(a)(1)(iv)). (b)(1) When the upper half...

  2. 49 CFR 572.145 - Upper and lower torso assemblies and torso flexion test procedure.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 49 Transportation 7 2011-10-01 2011-10-01 false Upper and lower torso assemblies and torso flexion... assemblies and torso flexion test procedure. (a) The test objective is to determine the resistance of the... upper and lower halves of the torso assembly (refer to § 572.140(a)(1)(iv)). (b)(1) When the upper half...

  3. 49 CFR 572.145 - Upper and lower torso assemblies and torso flexion test procedure.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 49 Transportation 7 2013-10-01 2013-10-01 false Upper and lower torso assemblies and torso flexion... assemblies and torso flexion test procedure. (a) The test objective is to determine the resistance of the... upper and lower halves of the torso assembly (refer to § 572.140(a)(1)(iv)). (b)(1) When the upper half...

  4. 49 CFR 572.165 - Upper and lower torso assemblies and torso flexion test procedure.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 49 Transportation 7 2010-10-01 2010-10-01 false Upper and lower torso assemblies and torso flexion... assemblies and torso flexion test procedure. (a) Upper/lower torso assembly. The test objective is to... (specified in 49 CFR 572.125(a)), on resistance to articulation between the upper torso assembly (drawing 167...

  5. 49 CFR 572.135 - Upper and lower torso assemblies and torso flexion test procedure.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 49 Transportation 7 2012-10-01 2012-10-01 false Upper and lower torso assemblies and torso flexion... torso assemblies and torso flexion test procedure. (a) Upper/lower torso assembly. The test objective is... (drawing 880105-434), on resistance to articulation between the upper torso assembly (drawing 880105-300...

  6. 49 CFR 572.125 - Upper and lower torso assemblies and torso flexion test procedure.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 49 Transportation 7 2014-10-01 2014-10-01 false Upper and lower torso assemblies and torso flexion... assemblies and torso flexion test procedure. (a) Upper/lower torso assembly. The test objective is to...), and abdominal insert (drawing 127-8210), on resistance to articulation between upper torso assembly...

  7. 49 CFR 572.135 - Upper and lower torso assemblies and torso flexion test procedure.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 49 Transportation 7 2013-10-01 2013-10-01 false Upper and lower torso assemblies and torso flexion... torso assemblies and torso flexion test procedure. (a) Upper/lower torso assembly. The test objective is... (drawing 880105-434), on resistance to articulation between the upper torso assembly (drawing 880105-300...

  8. 49 CFR 572.145 - Upper and lower torso assemblies and torso flexion test procedure.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 49 Transportation 7 2014-10-01 2014-10-01 false Upper and lower torso assemblies and torso flexion... assemblies and torso flexion test procedure. (a) The test objective is to determine the resistance of the... upper and lower halves of the torso assembly (refer to § 572.140(a)(1)(iv)). (b)(1) When the upper half...

  9. 49 CFR 572.125 - Upper and lower torso assemblies and torso flexion test procedure.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 49 Transportation 7 2011-10-01 2011-10-01 false Upper and lower torso assemblies and torso flexion... assemblies and torso flexion test procedure. (a) Upper/lower torso assembly. The test objective is to...), and abdominal insert (drawing 127-8210), on resistance to articulation between upper torso assembly...

  10. 49 CFR 572.125 - Upper and lower torso assemblies and torso flexion test procedure.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 49 Transportation 7 2012-10-01 2012-10-01 false Upper and lower torso assemblies and torso flexion... assemblies and torso flexion test procedure. (a) Upper/lower torso assembly. The test objective is to...), and abdominal insert (drawing 127-8210), on resistance to articulation between upper torso assembly...

  11. 49 CFR 572.135 - Upper and lower torso assemblies and torso flexion test procedure.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 49 Transportation 7 2011-10-01 2011-10-01 false Upper and lower torso assemblies and torso flexion... torso assemblies and torso flexion test procedure. (a) Upper/lower torso assembly. The test objective is... (drawing 880105-434), on resistance to articulation between the upper torso assembly (drawing 880105-300...

  12. 49 CFR 572.165 - Upper and lower torso assemblies and torso flexion test procedure.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 49 Transportation 7 2011-10-01 2011-10-01 false Upper and lower torso assemblies and torso flexion... assemblies and torso flexion test procedure. (a) Upper/lower torso assembly. The test objective is to... (specified in 49 CFR 572.125(a)), on resistance to articulation between the upper torso assembly (drawing 167...

  13. 49 CFR 572.125 - Upper and lower torso assemblies and torso flexion test procedure.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 49 Transportation 7 2013-10-01 2013-10-01 false Upper and lower torso assemblies and torso flexion... assemblies and torso flexion test procedure. (a) Upper/lower torso assembly. The test objective is to...), and abdominal insert (drawing 127-8210), on resistance to articulation between upper torso assembly...

  14. 49 CFR 572.165 - Upper and lower torso assemblies and torso flexion test procedure.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 49 Transportation 7 2014-10-01 2014-10-01 false Upper and lower torso assemblies and torso flexion... assemblies and torso flexion test procedure. (a) Upper/lower torso assembly. The test objective is to... (specified in 49 CFR 572.125(a)), on resistance to articulation between the upper torso assembly (drawing 167...

  15. The Effects of Psoas Major and Lumbar Lordosis on Hip Flexion and Sprint Performance

    ERIC Educational Resources Information Center

    Copaver, Karine; Hertogh, Claude; Hue, Olivier

    2012-01-01

    In this study, we analyzed the correlations between hip flexion power, sprint performance, lumbar lordosis (LL) and the cross-sectional area (CSA) of the psoas muscle (PM). Ten young adults performed two sprint tests and isokinetic tests to determine hip flexion power. Magnetic resonance imaging was used to determine LL and PM CSA. There were…

  16. Plantar pressure during running in subjects with chronic ankle instability.

    PubMed

    Morrison, Katherine E; Hudson, David J; Davis, Irene S; Richards, James G; Royer, Todd D; Dierks, Tracy A; Kaminski, Thomas W

    2010-11-01

    It has been suggested that dynamic foot and ankle mechanics predispose individuals with CAI to repetitive episodes of the ankle ``giving way.'' Plantar pressure variations during a walking gait have been detected in those with CAI, but more dynamic conditions for analysis are needed. The purpose of this study was to evaluate plantar pressure distributions during a running gait in individuals with CAI, individuals who suffered a lateral ankle sprain, but did not develop CAI (AS), and subjects with no history of a lateral ankle sprain (CON). Forty-five subjects [15 in each group, healthy males (18) and females (27), age 18 to 45] were recruited from University communities to participate in this study. Plantar pressure distributions were analyzed on a Tekscan© plantar pressure mat at 66 frames per second during a running gait at a controlled speed. The following variables were obtained: rearfoot medial/lateral (M/L) pressure ratio at foot strike (FS) and center-of-pressure (COP) trajectory during the initial loading response (heel strike to initial peak GRF). Separate one-way ANOVA with Tukey's post-hoc were used to test for group differences. The significance level was defined as p < 0.05. The CAI group had a significantly more lateral ratio (0.97 ± 0.12) at FS when compared to the CON (1.01 ± 0.13) and AS (1.11 ± 0.13) groups. The CAI subjects had a lateral COP trajectory during the loading phase (7.97 degrees ± 11.02), while both the AS (-3.68 degrees ± 10.24) and CON groups (-6.27 degrees ± 9.86) had medial trajectories. The difference was significant between the CAI group and both the AS and CON groups (all significant {\\it p} values were less than 0.05). Our results confirm that CAI subjects have a more lateral foot positioning and loading pattern during a barefoot running gait when compared to both the CON and LAS groups. Clinicians treating patients with CAI should consider providing interventions to decrease the amount of rearfoot inversion at FS and

  17. Long-Term Outcome of Open Plantar Fascia Release.

    PubMed

    MacInnes, Alasdair; Roberts, Sam C; Kimpton, Jessica; Pillai, Anand

    2016-01-01

    Plantar fasciitis is thought to be a self-limiting condition best treated by conservative measures, but despite this many patients have a prolonged duration of symptoms and surgery may be indicated. Partial plantar fascial release is reported to have a short-term success rate of up to 80%, but anecdotally this was not thought to represent our local experience. An audit of long-term patient-reported outcomes following open partial plantar fascia release was performed. A total of 30 patients (33 feet) were identified over a 10-year period and case notes were reviewed. Patients were contacted by letter and invited to complete 2 validated patient-reported outcome score questionnaires (Visual Analog Scale-Foot and Ankle [VAS-FA] and Manchester Oxford Foot Questionnaire [MOXFQ]). Responses were received from 24 patients (26 feet). The average ages were 42.4 (range 24-61) for male and 46.2 (range 33-60) for female patients, with a female/male ratio of 2.7:1. The average duration of treatment prior to operative intervention was 3.1 years (range 1-5). Preoperatively, our cohort underwent a range of conservative measures. All patients were reviewed postoperatively, and average time from surgery to completion of questionnaires was 80 months (range 14-130). The outcomes were worse in patients who had received preoperative steroid injections and this was found to be statistically significant. The mean MOXFQ score was 33.6 ± 3.9 (0-64). Mean VAS-FA score was 57.8 ± 4.9 (24-100). This study found a negative correlation between duration of follow-up and outcome, in both MOXFQ and VAS-FA, showing that patients continued to improve many years postoperatively. The authors also found worse outcomes with preoperative steroid injections, better outcomes in older patients, and a weak gender bias, suggesting results in men were better than those in women. A prolonged recovery period and generally poor outcomes leads the authors to suggest that open plantar fascia release is of

  18. Simultaneous characterizations of reflex and nonreflex dynamic and static changes in spastic hemiparesis

    PubMed Central

    Chung, Sun G.; Ren, Yupeng; Liu, Lin; Roth, Elliot J.; Rymer, W. Zev

    2013-01-01

    This study characterizes tonic and phasic stretch reflex and stiffness and viscosity changes associated with spastic hemiparesis. Perturbations were applied to the ankle of 27 hemiparetic and 36 healthy subjects under relaxed or active contracting conditions. A nonlinear delay differential equation model characterized phasic and tonic stretch reflex gains, elastic stiffness, and viscous damping. Tendon reflex was characterized with reflex gain and threshold. Reflexively, tonic reflex gain was increased in spastic ankles at rest (P < 0.038) and was not regulated with muscle contraction, indicating impaired tonic stretch reflex. Phasic-reflex gain in spastic plantar flexors was higher and increased faster with plantar flexor contraction (P < 0.012) than controls (P < 0.023) and higher in dorsi-flexors at lower torques (P < 0.038), primarily because of its increase at rest (P = 0.045), indicating exaggerated phasic stretch reflex especially in more spastic plantar flexors, which showed higher phasic stretch reflex gain than dorsi-flexors (P < 0.032). Spasticity was associated with increased tendon reflex gain (P = 0.002) and decreased threshold (P < 0.001). Mechanically, stiffness in spastic ankles was higher than that in controls across plantar flexion/dorsi-flexion torque levels (P < 0.032), and the more spastic plantar flexors were stiffer than dorsi-flexors at comparable torques (P < 0.031). Increased stiffness in spastic ankles was mainly due to passive stiffness increase (P < 0.001), indicating increased connective tissues/shortened fascicles. Viscous damping in spastic ankles was increased across the plantar flexion torque levels and at lower dorsi-flexion torques, reflecting increased passive viscous damping (P = 0.033). The more spastic plantar flexors showed higher viscous damping than dorsi-flexors at comparable torque levels (P < 0.047). Simultaneous characterizations of reflex and nonreflex changes in spastic hemiparesis may help to evaluate and treat

  19. Depression, Anxiety, and Stress in People With and Without Plantar Heel Pain.

    PubMed

    Cotchett, Matthew; Munteanu, Shannon E; Landorf, Karl B

    2016-08-01

    Depression, anxiety, and stress are prevalent in patients with musculoskeletal pain, but the impact of these emotional states has not been evaluated in people with plantar heel pain. The aim of this study was to evaluate the association between depression, anxiety, and stress with plantar heel pain. Forty-five participants with plantar heel pain were matched by sex and age (±2 years) to 45 participants without plantar heel pain. Levels of depression, anxiety, and stress were measured using the Depression, Anxiety and Stress Scale (short version) in participants with and without plantar heel pain. Logistic regression was conducted to determine if levels of depression, anxiety, or stress were associated with having plantar heel pain. Univariate analysis indicated that participants with plantar heel pain had greater levels of depression (mean difference = 4.4, 95% CI 2.3 to 6.5), anxiety (mean difference = 2.6, 95% CI 0.9 to 4.3), and stress (mean difference = 4.8, 95% CI 1.9 to 7.8). After adjusting for age, sex, BMI, and education, for every 1 unit increase in depression, anxiety, or stress (in the DASS subscales), the odds ratios for having plantar heel pain were increased by 1.3 (95% CI 1.1 to 1.6), 1.3 (95% CI 1.1 to 1.5), and 1.2 (95% CI 1.1 to 1.3), respectively. Symptoms of depression, anxiety, and stress were independently associated with plantar heel pain. Larger prospective studies are necessary to evaluate the temporal association between these emotional states and plantar heel pain. Level III, cross sectional, observational. © The Author(s) 2016.

  20. How Plantar Exteroceptive Efficiency Modulates Postural and Oculomotor Control: Inter-Individual Variability.

    PubMed

    Foisy, Arnaud; Kapoula, Zoï

    2016-01-01

    In a previous experiment, we showed that among young and healthy subjects, thin plantar inserts improve postural control and modify vergence amplitudes. In this experiment, however, significant inter-individual variability was observed. We hypothesize that its origin could be attributed to a different reliance upon feet cutaneous afferents. In order to test this hypothesis, we re-analyzed the data relative to 31 young (age 25.7 ± 3.8) and healthy subjects who participated in the first experiment after having classified them into two groups depending on their Plantar Quotient (PQ = Surface area of CoPfoam/Surface area of CoPfirm ground × 100). Foam decreases the information arising from the feet, normally resulting in a PQ > 100. Hence, the PQ provides information on the weight of plantar cutaneous afferents used in postural control. Twelve people were Plantar-Independent Subjects, as indicated by a PQ < 100. These individuals did not behave like the Normal Plantar Quotient Subjects: they were almost insensitive to the plantar stimulations in terms of postural control and totally insensitive in terms of oculomotor control. We conclude that the inter-individual variability observed in our first experiment is explained by the subjects' degree of plantar reliance. We propose that plantar independence is a dysfunctional situation revealing inefficiency in plantar cutaneous afferents. The latter could be due to a latent somatosensory dysfunction generating a noise which prevents the CNS from correctly processing and using feet somatosensory afferents both for balance and vergence control: Plantar Irritating Stimulus. Considering the non-noxious nature and prevalence of this phenomenon, these results can be of great interest to researchers and clinicians who attempt to trigger postural or oculomotor responses through mechanical stimulation of the foot sole.

  1. Intrinsic foot muscle volume in experienced runners with and without chronic plantar fasciitis.

    PubMed

    Cheung, R T H; Sze, L K Y; Mok, N W; Ng, G Y F

    2016-09-01

    Plantar fasciitis, a common injury in runners, has been speculated to be associated with weakness of the intrinsic foot muscles. A recent study reported that atrophy of the intrinsic forefoot muscles might contribute to plantar fasciitis by destabilizing the medial longitudinal arch. However, intrinsic foot muscle volume difference between individuals with plantar fasciitis and healthy counterparts remains unknown. This study examined the relationship of intrinsic foot muscle volume and incidence of plantar fasciitis. Case-control study. 20 experienced (≥5 years) runners were recruited. Ten of them had bilateral chronic (≥2 years) plantar fasciitis while the others were healthy characteristics-matched runners. Intrinsic muscle volumes of the participants' right foot were scanned with a 1.5T magnetic resonance system and segmented using established methods. Body-mass normalized intrinsic foot muscle volumes were compared between runners with and without chronic plantar fasciitis. There was significant greater rearfoot intrinsic muscle volume in healthy runners than runners with chronic plantar fasciitis (Cohen's d=1.13; p=0.023). A similar trend was also observed in the total intrinsic foot muscle volume but it did not reach a statistical significance (Cohen's d=0.92; p=0.056). Forefoot volume was similar between runners with and without plantar fasciitis. These results suggest that atrophy of intrinsic foot muscles may be associated with symptoms of plantar fasciitis in runners. These findings may provide useful information in rehabilitation strategies of chronic plantar fasciitis. Copyright © 2015 Sports Medicine Australia. Published by Elsevier Ltd. All rights reserved.

  2. Nonlinear finite element analysis of the plantar fascia due to the windlass mechanism.

    PubMed

    Cheng, Hsin-Yi Kathy; Lin, Chun-Li; Chou, Shih-Wei; Wang, Hsien-Wen

    2008-08-01

    Tightening of plantar fascia by passively dorsiflexing the toes during walking has functional importance. The purpose of this research was to evaluate the influence of big toe dorsiflexion angles upon plantar fascia tension (the windlass effect) with a nonlinear finite element approach. A two-dimensional finite element model of the first ray was constructed for biomechanical analysis. In order to imitate the windlass effect and to evaluate the mechanical responses of the plantar fascia under various conditions, 12 model simulations--three dorsiflexion angles of the big toe (45 degrees, 30 degrees, and 15 degrees), two plantar fascia properties (linear, nonlinear), and two weightbearing conditions (with body weight, without body weight)--were designed and analyzed. Our results demonstrated that nonlinear modeling of the plantar fascia provides a more sophisticated representation of experimental data than the linear one. Nonlinear plantar fascia setting also predicted a higher stress distribution along the fiber directions especially with larger toe dorsiflexion angles (45 degrees>30 degrees>15 degrees). The plantar fascia stress was found higher near the metatarsal insertion and faded as it moved toward the calcaneal insertion. Passively dorsiflexing the big toe imposes tension onto the plantar fascia. Windlass mechanism also occurs during stance phase of walking while the toes begin to dorsiflex. From a biomechanical standpoint, the plantar fascia tension may help propel the body upon its release at the point of push off. A controlled stretch via dorsiflexing the big toe may have a positive effect on treating plantar fasciitis by providing proper guidance for collagen regeneration. The windlass mechanism is also active during the stance phase of walking when the toes begin to dorsiflex.

  3. Quantitative tissue parameters of Achilles tendon and plantar fascia in healthy subjects using a handheld myotonometer.

    PubMed

    Orner, Sarah; Kratzer, Wolfgang; Schmidberger, Julian; Grüner, Beate

    2018-01-01

    The aim of the study was to examine the quantitative tissue properties of the Achilles tendon and plantar fascia using a handheld, non-invasive MyotonPRO device, in order to generate normal values and examine the biomechanical relationship of both structures. Prospective study of a large, healthy sample population. The study sample included 207 healthy subjects (87 males and 120 females) for the Achilles tendon and 176 healthy subjects (73 males and 103 females) for the plantar fascia. For the correlations of the tissue parameters of the Achilles tendon and plantar fascia an intersection of both groups was formed which included 150 healthy subjects (65 males and 85 females). All participants were measured in a prone position. Consecutive measurements of the Achilles tendon and plantar fascia were performed by MyotonPRO device at defined sites. For the left and right Achilles tendons and plantar fasciae all five MyotonPRO parameters (Frequency [Hz], Decrement, Stiffness [N/m], Creep and Relaxation Time [ms]) were calculated of healthy males and females. The correlation of the tissue parameters of the Achilles tendon and plantar fascia showed a significant positive correlation of all parameters on the left as well as on the right side. The MyotonPRO is a feasible device for easy measurement of passive tissue properties of the Achilles tendon and plantar fascia in a clinical setting. The generated normal values of the Achilles tendon and plantar fascia are important for detecting abnormalities in patients with Achilles tendinopathy or plantar fasciitis in the future. Biomechanically, both structures are positively correlated. This may provide new aspects in the diagnostics and therapy of plantar fasciitis and Achilles tendinopathy. Copyright © 2017 Elsevier Ltd. All rights reserved.

  4. Effects of plantar fascia stiffness on the biomechanical responses of the ankle-foot complex.

    PubMed

    Cheung, Jason Tak-Man; Zhang, Ming; An, Kai-Nan

    2004-10-01

    The plantar fascia is one of the major stabilizing structures of the longitudinal arch of human foot, especially during midstance of the gait cycle. Knowledge of its functional biomechanics is important for establishing the biomechanical rationale behind different rehabilitation, orthotic and surgical treatment of plantar fasciitis. This study aims at quantifying the biomechanical responses of the ankle-foot complex with different plantar fascia stiffness. A geometrical detailed three-dimensional finite element model of the human foot and ankle, incorporating geometric and contact nonlinearities was constructed by 3D reconstruction of MR images. A sensitivity study was conducted to evaluate the effects of varying elastic modulus (0-700 MPa) of the plantar fascia on the stress/strain distribution of the bony, ligamentous and encapsulated soft tissue structures. The results showed that decreasing the Young's modulus of plantar fascia would increase the strains of the long and short plantar and spring ligaments significantly. With zero fascia Young's modulus to simulate the plantar fascia release, there was a shift in peak von Mises stresses from the third to the second metatarsal bones and increased stresses at the plantar ligament attachment area of the cuboid bone. Decrease in arch height and midfoot pronation were predicted but did not lead to the total collapse of foot arch. Surgical dissection of the plantar fascia may induce excessive strains or stresses in the ligamentous and bony structures. Surgical release of plantar fascia should be well-planned to minimise the effect on its structural integrity to reduce the risk of developing arch instability and subsequent painful foot syndrome.

  5. 40 CFR 90.306 - Dynamometer torque cell calibration.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 40 Protection of Environment 20 2011-07-01 2011-07-01 false Dynamometer torque cell calibration... Emission Test Equipment Provisions § 90.306 Dynamometer torque cell calibration. (a)(1) Any lever arm used...-cell or transfer standard may be used to verify the torque measurement system. (1) The master load-cell...

  6. 40 CFR 90.306 - Dynamometer torque cell calibration.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 40 Protection of Environment 21 2013-07-01 2013-07-01 false Dynamometer torque cell calibration... Emission Test Equipment Provisions § 90.306 Dynamometer torque cell calibration. (a)(1) Any lever arm used...-cell or transfer standard may be used to verify the torque measurement system. (1) The master load-cell...

  7. 40 CFR 90.306 - Dynamometer torque cell calibration.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 40 Protection of Environment 21 2012-07-01 2012-07-01 false Dynamometer torque cell calibration... Emission Test Equipment Provisions § 90.306 Dynamometer torque cell calibration. (a)(1) Any lever arm used...-cell or transfer standard may be used to verify the torque measurement system. (1) The master load-cell...

  8. 40 CFR 1066.240 - Torque transducer verification and calibration.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ...) AIR POLLUTION CONTROLS VEHICLE-TESTING PROCEDURES Dynamometer Specifications § 1066.240 Torque transducer verification and calibration. Calibrate torque-measurement systems as described in 40 CFR 1065.310. ... 40 Protection of Environment 34 2013-07-01 2013-07-01 false Torque transducer verification and...

  9. 40 CFR 1066.240 - Torque transducer verification.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... POLLUTION CONTROLS VEHICLE-TESTING PROCEDURES Dynamometer Specifications § 1066.240 Torque transducer verification. Verify torque-measurement systems by performing the verifications described in §§ 1066.270 and... 40 Protection of Environment 33 2014-07-01 2014-07-01 false Torque transducer verification. 1066...

  10. Measurement of clinicians' ability to hand torque dental implant components.

    PubMed

    Kanawati, Ali; Richards, Mark W; Becker, Jeffery J; Monaco, Natalie E

    2009-01-01

    There is a varying degree of hand torque abilities using finger drivers among clinicians. Calibrating one's own abilities requires complicated instruments not readily available. This study evaluated a simple-to-use method that allows dental practitioners to have a quantifiable clinical assessment of relative torque ability using finger drivers to torque down dental implant components. A typodont that includes dental implants was mounted in a mannequin placed in a patient-reclined position. The subjects were asked to torque as tightly as they could a new healing abutment to an implant secured firmly in resin within the typodont. All participants wore moistened gloves when using a finger driver. The healing abutment was countertorqued using a certified precalibrated precision torque measurement device. The reading on the torque driver was recorded when the healing abutment disengaged. An average of torque values of dentists and dental students was calculated. Fifty subjects had an average maximum torque ability of 24 Ncm (male dentists: 28 Ncm; students: 22 Ncm; male students: 24 Ncm; female students: 19 Ncm). Maximum torque values for all participants ranged from 11 Ncm to 38 Ncm. There was no significant difference between groups. This study showed a varying degree of hand torquing abilities using a finger driver. Clinicians should regularly calibrate their ability to torque implant components to more predictably perform implant dentistry. Dental implant manufacturers should more precisely instruct clinicians as to maximum torque, as opposed to "finger tighten only".

  11. 40 CFR 1066.240 - Torque transducer verification and calibration.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ...) AIR POLLUTION CONTROLS VEHICLE-TESTING PROCEDURES Dynamometer Specifications § 1066.240 Torque transducer verification and calibration. Calibrate torque-measurement systems as described in 40 CFR 1065.310. ... 40 Protection of Environment 34 2012-07-01 2012-07-01 false Torque transducer verification and...

  12. 40 CFR 90.306 - Dynamometer torque cell calibration.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 40 Protection of Environment 20 2010-07-01 2010-07-01 false Dynamometer torque cell calibration... Emission Test Equipment Provisions § 90.306 Dynamometer torque cell calibration. (a)(1) Any lever arm used...-cell or transfer standard may be used to verify the torque measurement system. (1) The master load-cell...

  13. Influence of patellofemoral bracing on pain, knee extensor torque, and gait function in females with patellofemoral pain.

    PubMed

    Powers, Christopher M; Doubleday, Kathryn L; Escudero, Carina

    2008-01-01

    Our purpose was to evaluate the effects of a patellofemoral brace on pain response, knee extensor torque production, and gait function in females with patellofemoral pain (PFP). Sixteen females between the ages of 14 and 46 with diagnosis of PFP participated. Knee extensor torque was measured by using a LIDO isokinetic dynamometer. Pain levels were documented by using the Visual Analog Pain Scale. Stride characteristics during the conditions of free walk, fast walk, ascend stairs, descend stairs, ascend ramp, and descend ramp were obtained with a stride analyzer unit. EMG activity of the vasti musculature was recorded by using indwelling, bipolar, wire electrodes. Knee joint motion was assessed by using a VICON motion analysis system. All testing was performed with and without the Bauerfeind Genutrain P3 patellofemoral brace. There were no significant differences in torque production, pain levels, and stride characteristics between braced and non-braced trials. In addition, there were no significant differences in mean vasti EMG between braced and non-braced trials. When averaged across all conditions, a small but statistically significant increase in knee flexion was found during the braced trials. Although the current study did not find significant improvements in the clinical measures evaluated, 8 of the 16 subjects did experience a decrease in knee pain. This finding suggests that certain patients with PFP may respond favorably to bracing, and criteria must be established to determine which patients would best benefit from such an intervention.

  14. Acute effects of constant torque and constant angle stretching on the muscle and tendon tissue properties.

    PubMed

    Konrad, Andreas; Budini, Francesco; Tilp, Markus

    2017-08-01

    Static stretching induces acute structural changes of the muscle-tendon unit (MTU) that are related to the intensity or duration of stretching. It has been reported that stretching with a constant torque (CT) leads to greater joint range of motion changes than stretching with a constant angle (CA). Whether or not this difference is due to different structural changes of the MTUs of the lower leg and ankle plantar flexors is not known. Therefore, the purpose of this study was to compare the acute effects of single CA and CT stretching on various muscle and tendon mechanical properties. Seventeen young, healthy volunteers were tested on two separate days using either CT or CA stretching (4 × 30 s each). Before and after stretching, dorsiflexion range of motion (RoM), passive resistive torque (PRT), and maximum voluntary contraction (MVC) were measured with a dynamometer. Ultrasonography of the medial gastrocnemius (GM) muscle-tendon junction (MTJ) displacement allowed us to determine the length changes in the tendon and muscle, respectively, and hence to calculate their stiffness. Maximum dorsiflexion increased while PRT, muscle-tendon stiffness, and muscle stiffness decreased following both CA and CT stretching. There was a greater increase in RoM following CT stretching compared to CA stretching. Moreover, the decline in PRT was greater during CT stretching compared to CA stretching. As expected, several functional adaptations (RoM, PRT) were different between CT and CA stretching due to the higher intensity of CT stretching. However, no structural differences in the adaptations to the stretching modalities could be detected. We suggest that the different functional adaptations between CA and CT stretching are the consequence of different adaptations in the perception of stretch and pain.

  15. Smartphone assessment of knee flexion compared to radiographic standards.

    PubMed

    Dietz, Matthew J; Sprando, Daniel; Hanselman, Andrew E; Regier, Michael D; Frye, Benjamin M

    2017-03-01

    Measuring knee range of motion (ROM) is an important assessment for the outcomes of total knee arthroplasty. Recent technological advances have led to the development and use of accelerometer-based smartphone applications to measure knee ROM. The purpose of this study was to develop, standardize, and validate methods of utilizing smartphone accelerometer technology compared to radiographic standards, visual estimation, and goniometric evaluation. Participants used visual estimation, a long-arm goniometer, and a smartphone accelerometer to determine range of motion of a cadaveric lower extremity; these results were compared to radiographs taken at the same angles. The optimal smartphone position was determined to be on top of the leg at the distal femur and proximal tibia location. Between methods, it was found that the smartphone and goniometer were comparably reliable in measuring knee flexion (ICC=0.94; 95% CI: 0.91-0.96). Visual estimation was found to be the least reliable method of measurement. The results suggested that the smartphone accelerometer was non-inferior when compared to the other measurement techniques, demonstrated similar deviations from radiographic standards, and did not appear to be influenced by the person performing the measurements or the girth of the extremity. Copyright © 2016 Elsevier B.V. All rights reserved.

  16. Smartphone Assessment of Knee Flexion Compared to Radiographic Standards

    PubMed Central

    Dietz, Matthew J.; Sprando, Daniel; Hanselman, Andrew E.; Regier, Michael D.; Frye, Benjamin M.

    2017-01-01

    Purpose Measuring knee range of motion (ROM) is an important assessment for the outcomes of total knee arthroplasty. Recent technological advances have led to the development and use of accelerometer-based smartphone applications to measure knee ROM. The purpose of this study was to develop, standardize, and validate methods of utilizing smartphone accelerometer technology compared to radiographic standards, visual estimation, and goniometric evaluation. Methods Participants used visual estimation, a long-arm goniometer, and a smartphone accelerometer to determine range of motion of a cadaveric lower extremity; these results were compared to radiographs taken at the same angles. Results The optimal smartphone position was determined to be on top of the leg at the distal femur and proximal tibia location. Between methods, it was found that the smartphone and goniometer were comparably reliable in measuring knee flexion (ICC = 0.94; 95% CI: 0.91–0.96). Visual estimation was found to be the least reliable method of measurement. Conclusions The results suggested that the smartphone accelerometer was non-inferior when compared to the other measurement techniques, demonstrated similar deviations from radiographic standards, and did not appear to be influenced by the person performing the measurements or the girth of the extremity. PMID:28179062

  17. [Percutaneous surgery for plantar fasciitis due to a calcaneal spur].

    PubMed

    Apóstol-González, Saúl; Herrera, Jesús

    2009-01-01

    Determine the efficacy of percutaneous surgical treatment for talalgia due to a calcaneal spur. This is an observational, descriptive, clinical series analyzing the outcomes of 10 patients with a diagnosis of talalgia due to plantar fasciitis with a calcaneal spur treated with percutaneous foot surgery. The end result was assessed with a visual analog scale (VAS) to measure pain, the patients' opinion and their return to activities of daily living. Central tendency and scatter measurements were calculated. The inferential analysis was done with the non-parametric chi square (chi2) test. Most patients were females (90%) and mean age was 40.5 years. Follow-up was 12 months. One patient had bleeding of the approached area. Pain was reduced from 8 to 1.5 in the VAS. Nine patients returned to their activities. Two patients had occasional mild pain upon prolonged bipedestation. Ninety percent of results were satisfactory. Percutaneous foot surgery in talalgias caused by plantar fasciitis due to a calcaneal spur is a simple and effective method. It reduces the operative time and allows for an early return of patients to their activities of daily living.

  18. Application of plantar pressure assessment in footwear and insert design.

    PubMed

    Mueller, M J

    1999-12-01

    This clinical perspective describes the application of plantar pressure assessment in footwear and insert design. First, the rationale and evidence for using pressure assessment to assist in the design of footwear for patients with diabetes is described. I discuss 2 important measures obtained from pressure assessment: peak pressure, because it represents the magnitude of potential mechanical stresses that can contribute to skin breakdown, and contact area, because this identifies the treatment areas. Using measures obtained from pressure assessment, guidelines are presented to maximize contact area of the insert to the foot and reduce highest peak pressures on the skin, with the goal of preventing skin breakdown. Second, a rationale and guidelines are presented for the application of plantar pressure assessment in the evaluation and design of footwear for people without impairments (i.e., the general public). Finally, future applications of pressure assessment to improve the design and fit of shoes are discussed. Benefits and limitations of using pressure assessment to assist in footwear design are addressed throughout.

  19. Influence of intentional femoral component flexion in navigated TKA on gap balance and sagittal anatomy.

    PubMed

    Roßkopf, J; Singh, P K; Wolf, P; Strauch, M; Graichen, H

    2014-03-01

    Navigation has proven its ability to accurately restore coronal leg axis; however, for a good clinical outcome, other factors such as sagittal anatomy and balanced gaps are at least as important. In a gap-balanced technique, the size of the flexion gap is equalled to that of the extension gap. Flexion of the femoral component has been described as a theoretical possibility to balance flexion and extension gap. Aim of this study was to assess whether intentional femoral component flexion is helpful in balancing TKA gaps and in restoring sagittal anatomy. One hundred and thirty-one patients with TKA were included in this study. Implantation was performed in a navigated, gap-balanced, tibia-first technique. The femoral component flexion needed to equal flexion to extension gap was calculated based upon the navigation data. The sagittal diameter, the anterior and posterior offset were measured pre- and postoperatively based on the lateral radiographs. Medial and lateral gaps in extension and flexion as well as flexion/extension gap differences pre- and postoperatively were analysed. Additionally range of motion (ROM) and patient satisfaction (SF 12) were obtained. To achieve equal flexion and extension gap, the femoral component was flexed in 120 out of 131 patients showing mean flexion of 2.9° (SD 2.2°; navigation data) and 3.1° (SD 2.0°; radiological analysis), respectively. Based on this technique, it was possible to balance the extension gap (<2 mm difference) in 130 out of 131 patients (99%) and the flexion gap in 119 out of 131 (91%). The difference between extension and flexion gap was reduced from 39 to 24 out of 131 patients (81%) on the medial side and from 69 to 28 on the lateral side (79%). The sagittal diameter was restored in 114 out of 131 cases (87%); however, anterior offset was significantly reduced by 1.3 mm (SD 3.9°), and posterior offset was significantly increased by 1.6 mm (SD 3.3°). No correlation between any navigation and radiological

  20. Eccentric knee flexor torque following anterior cruciate ligament surgery.

    PubMed

    Osternig, L R; James, C R; Bercades, D T

    1996-10-01

    The purposes of this study were to compare eccentric knee flexor torque and muscle activation in the limbs of normal (NOR) subjects and in subjects who had undergone unilateral ACI, autograft surgical reconstruction (INJ) and to assess the effect of movement speed on EMG/ torque ratios and eccentric-concentric actions. Fourteen subjects (7 NOR and 7 INJ) were tested for knee eccentric flexor torque and EMG activity at four isokinetic speeds (15 degrees, 30 degrees, 45 degrees and 60 degrees.s-1). Results revealed that post-surgical limbs (ACL) produced significantly less (P < 0.05) eccentric torque and flexor EMG activity at 60 degrees.s-1 than uninjured (UNI) contralateral limbs. Eccentric torque rose significantly as speed increased from 45 degrees to 60 degrees.s-1 for surgical group uninjured limbs and NOR group left and right limbs. Eccentric flexor torque increased with speed for both groups and approximated equality with concentric extensor torque at 60 degrees.s-1 for INJ group ACL and UNI limbs. Concentric flexor muscle EMG/torque ratios were 30-191% greater than eccentric muscle actions across groups and speeds. The results suggest that ACL dysfunction may result in reduced eccentric flexor torque at rapid movement speeds, that eccentric flexor torque increases with movement speed and may have the capacity to counter forceful extensor concentric torque, and that eccentric muscle actions produce less muscle activation per unit force than concentric actions which may reflect reduced energy cost.

  1. Displaceable Spur Gear Torque Controlled Driver and Method

    NASA Technical Reports Server (NTRS)

    Cook, Joseph S., Jr. (Inventor)

    1996-01-01

    Methods and apparatus are provided for a torque driver including a laterally displaceable gear support member to carry an output spur gear. A biasing assembly biases the output spur gear into engagement with a pinion to which is applied an input torque greater than a desired output torque limit for a threaded fastener such as a nut or screw. A coiled output linkage connects the output spur gear with a fastener adaptor which may be a socket for a nut. A gear tooth profile provides a separation force that overcomes the bias to limit torque at the desired torque limit. Multiple fasteners may be rotated simultaneously to a desired torque limit if additional output spur gears are provided. A gauged selector mechanism is provided to laterally displace multiple driven members for fasteners arranged in differing configurations. The torque limit is selectably adjustable and may be different for fasteners within the same fastener configuration.

  2. Displaceable spur gear torque controlled driver and method

    NASA Technical Reports Server (NTRS)

    Cook, Joseph S., Jr. (Inventor)

    1994-01-01

    Methods and apparatus are provided for a torque driver including a laterally displaceable gear support member to carry an output spur gear. A biasing assembly biases the output spur gear into engagement with a pinion to which is applied an input torque greater than a desired output torque limit for a threaded fastener such as a nut or screw. A coiled output linkage connects the output spur gear with a fastener adaptor which may be a socket for a nut. A gear tooth profile provides a separation force that overcomes the bias to limit torque at the desired torque limit. Multiple fasteners may be rotated simultaneously to a desired torque limit if additional output spur gears are provided. A gauged selector mechanism is provided to laterally displace multiple driver members for fasteners arranged in differing configurations. The torque limit is selectably adjustable and may be different for fasteners within the same fastener configuration.

  3. A self-calibrating multicomponent force/torque measuring system

    NASA Astrophysics Data System (ADS)

    Marangoni, Rafael R.; Schleichert, Jan; Rahneberg, Ilko; Hilbrunner, Falko; Fröhlich, Thomas

    2018-07-01

    A multicomponent self-calibrating force and torque sensor is presented. In this system, the principle of a Kibble balance is adapted for the traceable force and torque measurement in three orthogonal directions. The system has two operating modes: the velocity mode and the force/torque sensing mode. In the velocity mode, the calibration of the sensor is performed, while in the force/torque sensing mode, forces and torques are measured by using the principle of the electromagnetic force compensation. Details about the system are provided, with the main components of the sensor and a description of the operational procedure. A prototype of the system is currently being implemented for measuring forces and torques in a range of  ±2 N and  ±0.1 N · m respectively. A maximal relative expanded measurement uncertainty (k  =  2) of 1 · 10‑4 is expected for the force and torque measurements.

  4. Risk factors correlated with plantar pressure in Chinese patients with type 2 diabetes.

    PubMed

    Qiu, Xuan; Tian, De-Hu; Han, Chang-Ling; Chen, Wei; Wang, Zhan-Jian; Mu, Zhen-Yun; Li, Xu; Liu, Kuan-Zhi

    2013-12-01

    Plantar pressure is a key factor for predicting ulceration in the foot of a diabetes patient. We recruited a group of 100 Chinese patients with type 2 diabetes and an age-, sex-, weight-, and height-matched group of 100 Chinese subjects without diabetes. We obtained plantar pressure data using a Footscan(®) gait system (RsScan International, Olen, Belgium) when the subjects with and without diabetes walked barefoot across a sensor platform. We recorded the maximum force, maximum pressure, impulse, pressure-time integral, and loading rate from 10 regions of the foot. We collected the data of 11 history-based variables, 10 anthropometric variables, and three metabolic variables regarding the clinical characteristics of the diabetes patients. Weight was identified as a determining factor for high plantar pressure. Height, the Neuropathy Symptom Score (NSS), and ankle-brachial index (ABI) were correlated positively with plantar pressure measurements, respectively. The sex, history of ulcer and callus, intima-media membrane of the lower limb blood vessels, and fasting blood glucose (FBG) could also explain a portion of the variability of the plantar pressure measurements. However, the correlations were low or weak. High plantar pressure in diabetes patients could be predicted, in part, based on weight, height, NSS, ABI, sex, history of ulcer and callus, intima-media membrane of the lower limb blood vessels, and FBG. Therefore, interventions should be taken specifically before high plantar pressure emerges.

  5. Sonoelastography in the Evaluation of Plantar Fasciitis Treatment: 3-Month Follow-Up After Collagen Injection.

    PubMed

    Kim, Minchul; Choi, Yun Sun; You, Myung-Won; Kim, Jin Su; Young, Ki Won

    2016-12-01

    The aim of this study was to investigate whether ultrasound elastography can demonstrate the outcome of the treatment in comparison with gray-scale imaging. Sixteen patients (mean age, 46.9 years) with plantar fasciitis were prospectively enrolled after unsuccessful conservative treatment. Individuals graded their heel pain on a 100-mm visual analogue scale (VAS) and underwent gray-scale ultrasonography and sonoelastography. Collagen was injected in the heels. Fascial thickness and hypoechogenicity, perifascial edema, and plantar fascial elasticity were evaluated. Follow-up sonoelastography and VAS grading were done 3 months after the injection. Statistical analyses were performed by the paired t test and the Fisher exact test. A P < 0.05 was considered statistically significant. Mean plantar fascial thickness showed insignificant decrease on follow-up (from 4.30 [1.37] to 4.23 [1.15] mm, P = 0.662). Fascial hypoechogenicity and perifascial edema did not change significantly after treatment. The mean strain ratio of the plantar fascia was significantly increased (from 0.71 [0.24] to 1.66 [0.72], P = 0.001). Softening of the plantar fascia decreased significantly after injection (from 12 to 3 ft, P = 0.004). Twelve (75%) of 16 patients showed significant VAS improvement at the follow-up. Sonoelastography revealed a hardening of the plantar fascia after collagen injection treatment and could aid in monitoring the improvement of the symptoms of plantar fasciitis, in cases where gray-scale imaging is inconclusive.

  6. Objective assessment of corticosteroid effect in plantar fasciitis: additional utility of ultrasound

    PubMed Central

    Moustafa, Asmaa Mahmoud Ali; Hassanein, Eshrak; Foti, Calogero

    2015-01-01

    Summary Background although plantar fascia thickening is well documented as a sonographic criterion for the diagnosis of plantar fasciitis (PF), however it was less evaluated as an objective measure of response to treatment. It is unknown to what extent if any different responses to different treatments are related to the ultrasound (US) morphology changes. We aimed to evaluate changes in US findings in correlation to pain reported. Methods this prospective observational trial included 21 plantar fasciitis patients (26 feet), resistant to conservative treatment for at least 2 months. Plantar fascia thickness and echogenicity were evaluated, compared to asymptomatic feet and correlated with visual analogue scale (VAS) and Heel Tenderness Index (HTI), before and after dexam-ethasone (DXM) iontophoresis in group I, and DXM injection in group II. Results increased thickness and reduced echogenicity were constant in symptomatic feet, with high statistical significant difference compared to asymptomatic side. Correlation between plantar fascia thickness with VAS and HTI before and after treatment showed statistically significant positive correlation (p<0.05). ROC curve test showed that reduction of plantar fascia thickness by US in response to DXM had 100% sensitivity, 65.2% specificity and 69% accuracy, with higher specificity and accuracy than VAS. Conclusion US changes showed concurrent validity correlated with self-reported clinical improvement. Accordingly, ultrasound can be considered an objective useful tool for monitoring response to corticosteroid in patients with plantar fasciitis. PMID:26958538

  7. Objective assessment of corticosteroid effect in plantar fasciitis: additional utility of ultrasound.

    PubMed

    Moustafa, Asmaa Mahmoud Ali; Hassanein, Eshrak; Foti, Calogero

    2015-01-01

    although plantar fascia thickening is well documented as a sonographic criterion for the diagnosis of plantar fasciitis (PF), however it was less evaluated as an objective measure of response to treatment. It is unknown to what extent if any different responses to different treatments are related to the ultrasound (US) morphology changes. We aimed to evaluate changes in US findings in correlation to pain reported. this prospective observational trial included 21 plantar fasciitis patients (26 feet), resistant to conservative treatment for at least 2 months. Plantar fascia thickness and echogenicity were evaluated, compared to asymptomatic feet and correlated with visual analogue scale (VAS) and Heel Tenderness Index (HTI), before and after dexam-ethasone (DXM) iontophoresis in group I, and DXM injection in group II. increased thickness and reduced echogenicity were constant in symptomatic feet, with high statistical significant difference compared to asymptomatic side. Correlation between plantar fascia thickness with VAS and HTI before and after treatment showed statistically significant positive correlation (p<0.05). ROC curve test showed that reduction of plantar fascia thickness by US in response to DXM had 100% sensitivity, 65.2% specificity and 69% accuracy, with higher specificity and accuracy than VAS. US changes showed concurrent validity correlated with self-reported clinical improvement. Accordingly, ultrasound can be considered an objective useful tool for monitoring response to corticosteroid in patients with plantar fasciitis.

  8. Achilles tendon and plantar fascia in recently diagnosed type II diabetes: role of body mass index.

    PubMed

    Abate, Michele; Schiavone, Cosima; Di Carlo, Luigi; Salini, Vincenzo

    2012-07-01

    Previous research has shown that plantar fascia and Achilles tendon thickness is increased in diabetes. The aims of present study were to assess whether tendon changes can occur in the early stages of the disease and to evaluate the extent of the influence of body mass index (BMI). The study population included 51 recent-onset type II diabetic subjects, who were free from diabetic complications, divided according to BMI into three groups (normal weight, overweight, and obese). Eighteen non-diabetic, normal-weight subjects served as controls. Plantar fascia and Achilles tendon thickness was measured by means of sonography. The groups were well balanced for age and sex. In all the diabetic subjects, plantar fascia and Achilles tendon thickness was increased compared to the controls (p < 0.001, p = 0.01, p = 0.003, respectively). A significant relationship was found between plantar fascia thickness and BMI values (r = 0.749, p < 0.0001), while the correlation between BMI and Achilles tendon was weaker (r = 0.399, p = 0.004). This study shows that plantar fascia and Achilles tendon thickness is increased in the early stages of type II diabetes and that BMI is related more to plantar fascia than Achilles tendon thickness. Further longitudinal studies are needed to evaluate whether these early changes can overload the metatarsal heads and increase the stress transmitted to plantar soft tissues, thus representing an additional risk factor for foot ulcer development.

  9. Plantar Fasciitis and the Windlass Mechanism: A Biomechanical Link to Clinical Practice

    PubMed Central

    Malone, Terry R.

    2004-01-01

    Objective: Plantar fasciitis is a prevalent problem, with limited consensus among clinicians regarding the most effective treatment. The purpose of this literature review is to provide a systematic approach to the treatment of plantar fasciitis based on the windlass mechanism model. Data Sources: We searched MEDLINE, SPORT Discus, and CINAHL from 1966 to 2003 using the key words plantar fasciitis, windlass mechanism, pronation, heel pain, and heel spur. Data Synthesis: We offer a biomechanical application for the evaluation and treatment of plantar fasciitis based on a review of the literature for the windlass mechanism model. This model provides a means for describing plantar fasciitis conditions such that clinicians can formulate a potential causal relationship between the conditions and their treatments. Conclusions/Recommendations: Clinicians' understanding of the biomechanical causes of plantar fasciitis should guide the decision-making process concerning the evaluation and treatment of heel pain. Use of this approach may improve clinical outcomes because intervention does not merely treat physical symptoms but actively addresses the influences that resulted in the condition. Principles from this approach might also provide a basis for future research investigating the efficacy of plantar fascia treatment. PMID:16558682

  10. Mode coupling in spin torque oscillators

    DOE PAGES

    Zhang, Steven S. -L.; Zhou, Yan; Li, Dong; ...

    2016-09-15

    A number of recent experimental works have shown that the dynamics of a single spin torque oscillator can exhibit complex behavior that stems from interactions between two or more modes of the oscillator, such as observed mode-hopping or mode coexistence. There has been some initial work indicating how the theory for a single-mode (macro-spin) spin torque oscillator should be generalized to include several modes and the interactions between them. In the present work, we rigorously derive such a theory starting with the Landau–Lifshitz–Gilbert equation for magnetization dynamics by expanding up to third-order terms in deviation from equilibrium. Here, our resultsmore » show how a linear mode coupling, which is necessary for observed mode-hopping to occur, arises through coupling to a magnon bath. In conclusion, the acquired temperature dependence of this coupling implies that the manifold of orbits and fixed points may shift with temperature.« less

  11. A dynamic method for magnetic torque measurement

    NASA Technical Reports Server (NTRS)

    Lin, C. E.; Jou, H. L.

    1994-01-01

    In a magnetic suspension system, accurate force measurement will result in better control performance in the test section, especially when a wider range of operation is required. Although many useful methods were developed to obtain the desired model, however, significant error is inevitable since the magnetic field distribution of the large-gap magnetic suspension system is extremely nonlinear. This paper proposed an easy approach to measure the magnetic torque of a magnetic suspension system using an angular photo encoder. Through the measurement of the velocity change data, the magnetic torque is converted. The proposed idea is described and implemented to obtain the desired data. It is useful to the calculation of a magnetic force in the magnetic suspension system.

  12. Spin diffusion and torques in disordered antiferromagnets

    NASA Astrophysics Data System (ADS)

    Manchon, Aurelien

    2017-03-01

    We have developed a drift-diffusion equation of spin transport in collinear bipartite metallic antiferromagnets. Starting from a model tight-binding Hamiltonian, we obtain the quantum kinetic equation within Keldysh formalism and expand it to the lowest order in spatial gradient using Wigner expansion method. In the diffusive limit, these equations track the spatio-temporal evolution of the spin accumulations and spin currents on each sublattice of the antiferromagnet. We use these equations to address the nature of the spin transfer torque in (i) a spin-valve composed of a ferromagnet and an antiferromagnet, (ii) a metallic bilayer consisting of an antiferromagnet adjacent to a heavy metal possessing spin Hall effect, and in (iii) a single antiferromagnet possessing spin Hall effect. We show that the latter can experience a self-torque thanks to the non-vanishing spin Hall effect in the antiferromagnet.

  13. Six component robotic force-torque sensor

    NASA Technical Reports Server (NTRS)

    Grahn, Allen R.; Hutchings, Brad L.; Johnston, David R.; Parsons, David C.; Wyatt, Roland F.

    1987-01-01

    The results of a two-phase contract studying the feasibility of a miniaturized six component force-torque sensor and development of a working laboratory system were described. The principle of operation is based upon using ultrasonic pulse-echo ranging to determine the position of ultrasonic reflectors attached to a metal or ceramic cover plate. Because of the small size of the sensor, this technology may have application in robotics, to sense forces and torques at the finger tip of a robotic end effector. Descriptions are included of laboratory experiments evaluating materials and techniques for sensor fabrication and of the development of support electronics for data acquisition, computer interface, and operator display.

  14. Manipulation of spin transfer torque using light

    NASA Astrophysics Data System (ADS)

    Rontani, Massimo; Vendelbjerg, Karsten; Sham, Lu

    We show that the spin transfer torque induced by a spin-polarized current on a nanomagnet as the current flows through a semiconductor-nanomagnet-semiconductor junction is externally controlled by shining the junction off-resonantly with a strong laser beam. The excitonic coherence driven by the laser dresses the virtual electron-hole pairs coupling conduction and valence bands and inducing an evanescent state in the proximity of the nanomagnet. The Fano-like quantum interference between this localized state and the continuum spectrum is different in the two spin channels and hence it dramatically alters the spin transport, leading to the coherent control of the spin transfer torque. This work is supported by EU-FP7 Marie Curie Initial Training Network INDEX.

  15. Torque Transmission Device at Zero Leakage

    NASA Technical Reports Server (NTRS)

    Hendricks, R. C.; Mullen, R. L.

    2005-01-01

    In a few critical applications, mechanical transmission of power by rotation at low speed is required without leakage at an interface. Herein we examine a device that enables torque to be transmitted across a sealed environmental barrier. The barrier represents the restraint membrane through which the torque is transmitted. The power is transferred through elastic deformation of a circular tube into an elliptical cross-section. Rotation of the principle axis of the ellipse at one end results in a commensurate rotation of an elliptical cross section at the other end of the tube. This transfer requires no rigid body rotation of the tube allowing a membrane to seal one end from the other. Both computational and experimental models of the device are presented.

  16. Articular contact pressures of meniscal repair techniques at various knee flexion angles.

    PubMed

    Flanigan, David C; Lin, Fang; Koh, Jason L; Zhang, Li-Qun

    2010-07-13

    Articular cartilage injury can occur after meniscal repair with biodegradable implants. Previous contact pressure analyses of the knee have been based on the tibial side of the meniscus at limited knee flexion angles. We investigated articular contact pressures on the posterior femoral condyle with different knee flexion angles and surgical repair techniques. Medial meniscus tears were repaired in 30 fresh bovine knees. Knees were mounted on a 6-degrees-of-freedom jig and statically loaded to 200 N at 45 degrees, 70 degrees, 90 degrees, and 110 degrees of knee flexion under 3 conditions: intact meniscus, torn meniscus, and meniscus after repair. For each repair, 3 sutures or biodegradable implants were used. A pressure sensor was used to determine the contact area and peak pressure. Peak pressures over each implant position were measured. Peak pressure increased significantly as knee flexion increased in normal, injured, and repaired knees. The change in peak pressure in knees with implant repairs was significantly higher than suture repairs at all knee flexion angles. Articular contact pressure on the posterior femoral condyle increased with knee flexion. Avoidance of deep knee flexion angles postoperatively may limit increases in articular contact pressures and potential chondral injury. Copyright 2010, SLACK Incorporated.

  17. Torque and mechanomyogram relationships during electrically-evoked isometric quadriceps contractions in persons with spinal cord injury.

    PubMed

    Ibitoye, Morufu Olusola; Hamzaid, Nur Azah; Hasnan, Nazirah; Abdul Wahab, Ahmad Khairi; Islam, Md Anamul; Kean, Victor S P; Davis, Glen M

    2016-08-01

    The interaction between muscle contractions and joint loading produces torques necessary for movements during activities of daily living. However, during neuromuscular electrical stimulation (NMES)-evoked contractions in persons with spinal cord injury (SCI), a simple and reliable proxy of torque at the muscle level has been minimally investigated. Thus, the purpose of this study was to investigate the relationships between muscle mechanomyographic (MMG) characteristics and NMES-evoked isometric quadriceps torques in persons with motor complete SCI. Six SCI participants with lesion levels below C4 [(mean (SD) age, 39.2 (7.9) year; stature, 1.71 (0.05) m; and body mass, 69.3 (12.9) kg)] performed randomly ordered NMES-evoked isometric leg muscle contractions at 30°, 60° and 90° knee flexion angles on an isokinetic dynamometer. MMG signals were detected by an accelerometer-based vibromyographic sensor placed over the belly of rectus femoris muscle. The relationship between MMG root mean square (MMG-RMS) and NMES-evoked torque revealed a very high association (R(2)=0.91 at 30°; R(2)=0.98 at 60°; and R(2)=0.97 at 90° knee angles; P<0.001). MMG peak-to-peak (MMG-PTP) and stimulation intensity were less well related (R(2)=0.63 at 30°; R(2)=0.67 at 60°; and R(2)=0.45 at 90° knee angles), although were still significantly associated (P≤0.006). Test-retest interclass correlation coefficients (ICC) for the dependent variables ranged from 0.82 to 0.97 for NMES-evoked torque, between 0.65 and 0.79 for MMG-RMS, and from 0.67 to 0.73 for MMG-PTP. Their standard error of measurements (SEM) ranged between 10.1% and 31.6% (of mean values) for torque, MMG-RMS and MMG-PTP. The MMG peak frequency (MMG-PF) of 30Hz approximated the stimulation frequency, indicating NMES-evoked motor unit firing rate. The results demonstrated knee angle differences in the MMG-RMS versus NMES-isometric torque relationship, but a similar torque related pattern for MMG-PF. These findings

  18. Adjustable-Torque Truss-Joint Mechanism

    NASA Technical Reports Server (NTRS)

    Bush, Harold G.; Wallsom, Richard E.

    1993-01-01

    Threaded pin tightened or loosened; tedious trial-and-error procedure shortened. Mechanism joining strut and node in truss structure preloaded to desired stress to ensure tight, compressive fit preventing motion of strut during loading or vibration. Preload stress on stack of Belleville spring washers adjusted by tightening or loosening threaded Belleville-washer-alignment pin. Pin turned, by use of allen wrench, to adjust compression preload on Belleville washers and adjusts joint-operating torque.

  19. An ironless armature brushless torque motor

    NASA Technical Reports Server (NTRS)

    Studer, P. A.

    1973-01-01

    A high torque motor with improved servo mechanism is reported. Armature windings are cast into an epoxy cylinder and armature conductors are integrally cast with an aluminum mounting ring which provides thermal conductance directly into the structure. This configuration eliminates magnetic hysteresis because there is no relative motion between the rotating magnetic field and any stationary iron. The absence of destabilization forces provides a fast electrical response compared with a typical torquer of conventional construction.

  20. Using Plantar Electrical Stimulation to Improve Postural Balance and Plantar Sensation Among Patients With Diabetic Peripheral Neuropathy: A Randomized Double Blinded Study

    PubMed Central

    Najafi, Bijan; Talal, Talal K.; Grewal, Gurtej Singh; Menzies, Robert; Armstrong, David G.; Lavery, Lawrence A.

    2017-01-01

    Objective: People with diabetic peripheral neuropathy (DPN) often exhibit deteriorations in motor-performance mainly due to lack of plantar-sensation. The study explored effectiveness of plantar electrical-stimulation therapy to enhance motor-performance among people with DPN. Design and methods: Using a double-blinded model, 28 volunteers with DPN (age: 57.8 ± 10.2 years) were recruited and randomized to either intervention (IG: n = 17) or control (CG: n = 11) group. Both groups received identical plantar-stimulation devices for six weeks of daily use at home; however, only the IG devices were set to deliver stimulation. Balance (ankle, hip, and center of mass [COM] sway) and gait (stride velocity [SV], stride time [ST], stride length [SL], and cadence) were measured using validated wearable sensors. Outcomes were assessed at baseline and at six-week. Clinical assessment including vascular as measured by ankle-brachial-index (ABI) and plantar-sensation as quantified by vibratory plantar threshold (VPT) were also measured at baseline and six weeks. Results: No difference were observed between groups for baseline characteristics (P > .050). Posttherapy, ankle and COM sway with eyes open were significantly improved (P < .05, Cohen’s effect size d = 0.67-0.76) in the IG with no noticeable changes in CG. All gait parameters were significantly improved in the IG with highest effect size observed for cadence (d = 1.35, P = .000). Results revealed improvement in VPT (P = .004, d = 1.15) with significant correlation with stride velocity improvement (r = .56, P = .037). ABI was improved in the IG in particulate among those with ABI>1.20 (P = .041, d = 0.99) Conclusion: This study suggests that daily home use of plantar electrical-stimulation may be a practical means to enhance motor-performance and plantar-sensation in people with DPN. PMID:28627217