Search results for "ACHILLE"

Structure and function of human triceps surae muscle and tendon in aging

2016

Muscle-tendon glucose uptake in Achilles tendon rupture and tendinopathy before and after eccentric rehabilitation: Comparative case reports

2016

Achilles tendon rupture (ATR) is the most common tendon rupture injury. The consequences of ATR on metabolic activity of the Achilles tendon and ankle plantarflexors are unknown. Furthermore, the effects of eccentric rehabilitation on metabolic activity patterns of Achilles tendon and ankle plantarflexors in ATR patients have not been reported thus far. We present a case study demonstrating glucose uptake (GU) in the Achilles tendon, the triceps surae, and the flexor hallucis longus of a post-surgical ATR patient before and after a 5-month eccentric rehabilitation. At baseline, three months post-surgery, all muscles and Achilles tendon displayed much higher GU in the ATR patient compared to…

Assessment of tensile mechanical properties of the Achilles tendon in adult patients with haemophilic arthropathy.

2019

Internalized myofiber capillaries: Observations on their origin and clinical features

1989

Internalized capillaries limited to type 1 muscle fibers were noted in seven patients. They occurred in each case in association with a similar admixture of neurogenic and myopathic features that included atrophic and hypertrophic fibers, internal nuclei, fiber splitting, and endomyseal and perimyseal fibrosis. Internalized capillaries in enlarged type 1 fibers arose from fiber splits on step section study of four patients. They occurred in the gastrocnemius, quadriceps, and soleus muscles from patients with a variety of disorders that included Becker dystrophy, diabetes mellitus and strenuous leg activities, Achilles tendon rupture, and myotonic dystrophy. Exercise-induced myalgias were no…

Real-time spatial compound sonography of Achilles tendon in patients with heterozygous familial hypercholesterolaemia and normal physical examination

2007

This study was undertaken to assess the prevalence and ultrasound features of Achilles tendon xanthomas (ATX) in patients with heterozygous familial hypercholesterolemia (HFH) and normal physical examination studied with high-resolution ultrasonography (HRUS) and, secondarily, to evaluate the role of real-time spatial compound sonography (CS) in terms of image quality.Both Achilles tendons of 40 patients with HFH were studied with HRUS and CS. Two experienced radiologists evaluated by consensus the presence of ATX described as (1) tendon thickening and/or (2) focal hypoechoic areas and the quality of images obtained with the two techniques.Ten out of 80 tendons showed thickening (mean: 11.2…

In-Vivo Estimation and Repeatability of Force-Length Relationship and Stiffness of the Human Achilles Tendon using Phase Contrast MRI

2008

Purpose To devise a method using velocity encoded phase contrast MRI and MR-compatible dynamometry, for in vivo estimation of elastic properties of the human Achilles tendon and to assess within-session and day-to-day repeatability of this technique. Materials and Methods Achilles tendon force and calcaneus-movement-adjusted displacement were measured during a submaximal isometric plantarflexion in 4 healthy subjects, four repeated trials each. The measured force-length (F-L) relationship was least-squares fitted to a cubic polynomial. Typical error was calculated for tendon displacement at multiple force levels, stiffness from the “linear region,” and transition point from the displacement…

A comparison of the triceps surae and residual muscle moments at the ankle during cycling.

1991

The rigid linked system model and principles of inverse dynamics have been widely used to calculate residual muscle moments during various activities. EMG driven models and optimization algorithms have also been presented in the literature in efforts to estimate skeletal muscle forces and evaluate their possible contribution to the residual muscle moment. Additionally, skeletal muscle-tendon forces have been measured, directly, in both animals and humans. The purpose of this investigation was to calculate the moment produced by the triceps surae muscles and compare it to the residual muscle moment at the ankle during cycling at three power outputs (90, 180 and 270 W). Inferences were made r…

Effect of chronic unloading and rehabilitation on human Achilles tendon properties: a velocity-encoded phase-contrast MRI study

2008

The objective of this study was to measure and monitor changes in Achilles tendon mechanical properties and force production capability of triceps surae muscles after 4 wk of limb suspension and 6 wk of physical rehabilitation. Five healthy volunteers underwent unilateral lower limb suspension followed by weekly physiotherapy. A velocity-encoded, phase-contrast magnetic resonance imaging (VE-PC-MRI) technique was used to estimate the tendon strain as a function of force produced during the submaximal isometric contractions. After limb suspension, triceps surae muscle strength decreased to 53.2 ± 15.6% (mean ± SD) of the presuspension level ( P < 0.05). Young's modulus, estimated from the…

Non‐uniform displacement within ruptured Achilles tendon during isometric contraction

2021

The purpose of this study was investigate tendon displacement patterns in non-surgically treated patients 14 months after acute Achilles tendon rupture (ATR) and to classify patients into groups based on their Achilles tendon (AT) displacement patterns. Twenty patients were tested. Sagittal images of AT were acquired using B-mode ultrasonography during ramp contractions at a torque level corresponding to 30% of the maximal isometric plantarflexion torque of the uninjured limb. A speckle tracking algorithm was used to track proximal-distal movement of the tendon tissue at 6 antero-posterior locations. Two-way repeated measures ANOVA for peak tendon displacement was performed. K-means cluster…

Distinct muscle-tendon interaction during running at different speeds and in different loading conditions.

2019

The interaction between the Achilles tendon and the triceps surae muscles seems to be modulated differently with various task configurations. Here we tested the hypothesis that the increased forces and ankle joint work during running under contrasting conditions (altered speed or load) would be met by different, time-dependent adjustments at the muscle-tendon level. Ultrasonography, electromyography, kinematics, and ground reaction force measurements were used to examine Achilles tendon, gastrocnemius, and soleus muscle mechanics in 16 runners in four different running conditions, consisting of a combination of two different speeds (preferred and +20% of preferred speed) and two loading co…