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
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...
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...
OBJECTIVE To develop a method to maintain the initial phenotype of airway smooth muscle (ASM) cells isolated from equine endobronchial biopsy specimens in long-term cell culture. SAMPLE Endobronchial ...
Perivascular adipose tissue (PVAT) is now recognised as an active player in vascular homeostasis. Expansion of PVAT in obesity and the possible role of PVAT in vascular dysfunction has attracted much ...
Restrictive leaflet tethering resulting from regional left ventricular (LV) contractile injury causes ischemic mitral regurgitation (MR). We hypothesized that 3-dimensional LV topographic mapping by M...
Patients with inherited muscle diseases can have several problems in their muscles, which can be both structural and metabolic. All the different diseases can affect the contractility of t...
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...
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.
Multiprotein complexes in GRAM NEGATIVE BACTERIA that deliver effector proteins into eukaryotic or prokaryotic cells by a mechanism similar to the contractile tail of bacteriophages. They are composed of a cell envelope-spanning tube which is surrounded by a contractile sheath and tipped by a cell puncturing complex; a base plate structure that anchors the assembly to the cell envelope; and an ATPase involved in the sheath contraction and disassembly of the complex.
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.
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...