Track topics on Twitter Track topics that are important to you
Magnetic resonance imaging (MRI) enables accurate in vivo quantification of human muscle volumes, which can be used to estimate subject-specific muscle force capabilities. An important consideration is the amount of contractile and non-contractile tissue in the muscle compartment, which will influence force capability. We quantified age-related differences in the proportion and distribution of contractile and non-contractile tissue in the dorsiflexor and plantar flexor (soleus, and medial and lateral heads of gastrocnemius) muscles, and examined how well these volumes can be estimated from single MRI cross-sections. Axial MRIs of the left leg for 12 young (mean age 27 years) and 12 older (72 years) healthy, active adults were used to compute muscle volumes. Contractile tissue distribution along the leg was characterized by mathematical functions to allow volume prediction from single-slice cross-sectional area (CSA) measurements. Compared to young, older adults had less contractile volume and a greater proportion of non-contractile tissue. In both age groups the proportion of non-contractile tissue increased distally, with the smallest proportion near the maximum compartment CSA. A single CSA measurement predicted contractile volume with 8-11% error, with older adults in the higher end of this range. Using multiple slices improved volume estimates by roughly 50%, with average errors of about 3-4%. These results demonstrate significant age-related differences in non-contractile tissue for the dorsi- and plantar-flexor muscles. Although estimates of contractile volume can be obtained from single CSA measurements, multiple slices are needed for increased accuracy due to inter-individual variations in muscle volume and composition.
Biomechanics Laboratory, Department of Kinesiology, University of Massachusetts Amherst, USA.
This article was published in the following journal.
Name: Journal of biomechanics
Sepsis is associated with cardiac contractile dysfunction attributed to alterations in Ca handling. We examined the subcellular mechanisms involved in sarcoplasmic reticulum Ca loss that mediate alter...
Accessory muscles are relatively rare anatomic duplications of muscles that may appear anywhere in the muscular system. Though a wide array of accessory and supernumery muscles involving the ankle hav...
Plantarflexor tightness due to muscle degenerations has been frequently documented in children with spastic cerebral palsy but the contractile behavior of muscles during ambulation is largely unclear....
We investigated whether a linear relationship between muscle strength and cross-sectional area (CSA) is preserved in calf muscles of patients with Becker and Limb-girdle type 2I muscular dystrophies (...
Microtubule (MT) networks play key roles in cell division, intracellular transport, and cell motility. These functions of MT networks occur through interactions between MTs and various associated prot...
Muscle proteins accumulate damage during aging and leads to the loss of muscle mass and function in older people. Exercise can increase the making of new proteins and removal of older pro...
Viability assessment remains a clinical challenge in patient with coronary artery disease and left ventricular dysfunction. Several imaging modalities are available for evaluating myocardi...
Impaired contractile function after a heart attack and due to coronary heart disease is a major cause of "heart failure" limiting quality of life and prognosis, which cannot be prevented e...
Mitochondrial disorders are a group of inherited disorders causing malfunctional mitochondria. Mitochondria are found in every cell of the body, and the disorders therefore give symptoms f...
To assess changes in cardiac contractile function, as they relate to metabolic parameters, in clinically severe obese patients undergoing bariatric surgery.
Proteins which participate in contractile processes. They include MUSCLE PROTEINS as well as those found in other cells and tissues. In the latter, these proteins participate in localized contractile events in the cytoplasm, in motile activity, and in cell aggregation phenomena.
Contractile tissue that produces movement in animals.
Spindle-shaped cells with characteristic CONTRACTILE PROTEINS and structures that contribute to the WOUND HEALING process. They occur in GRANULATION TISSUE and also in pathological processes such as FIBROSIS.
The muscle tissue of the HEART. It is composed of striated, involuntary muscle cells (MYOCYTES, CARDIAC) connected to form the contractile pump to generate blood flow.
Accumulation of a drug or chemical substance in various organs (including those not relevant to its pharmacologic or therapeutic action). This distribution depends on the blood flow or perfusion rate of the organ, the ability of the drug to penetrate organ membranes, tissue specificity, protein binding. The distribution is usually expressed as tissue to plasma ratios.
Radiology is the branch of medicine that studies imaging of the body; X-ray (basic, angiography, barium swallows), ultrasound, MRI, CT and PET. These imaging techniques can be used to diagnose, but also to treat a range of conditions, by allowing visuali...
Arthritis Fibromyalgia Gout Lupus Rheumatic Rheumatology is the medical specialty concerned with the diagnosis and management of disease involving joints, tendons, muscles, ligaments and associated structures (Oxford Medical Diction...
Within medicine, nutrition (the study of food and the effect of its components on the body) has many different roles. Appropriate nutrition can help prevent certain diseases, or treat others. In critically ill patients, artificial feeding by tubes need t...