Complete Adipose Replacement of Bilateral Medial Gastrocnemius Muscle - A Cadaveric Case Report

Sarcopenia and infiltration of intermuscular adipose tissue are often seen in older adults due to aging process, but a muscle is completely replaced by adipose tissue is rarely reported. In this cadaveric case, we describe an observation of bilateral symmetric adipose replacement of the medial gastrocnemius muscles (GM) on both left and right leg in an 82-year old Caucasian female, whose cause of death was advanced dementia. The white adipose tissue replaced the entire medial GM muscle belly with pennate-like arrangement, indicating adipose tissue infiltration very likely into the original muscle cells. Where and how these adipose tissues come from are discussed.

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Characterization of passive elastic properties of the human medial gastrocnemius muscle belly using supersonic shear imaging

Journal of Biomechanics ◽

10.1016/j.jbiomech.2012.01.009 ◽

2012 ◽

Vol 45 (6) ◽

pp. 978-984 ◽

Cited By ~ 152

Author(s):

Olivier Maïsetti ◽

François Hug ◽

Killian Bouillard ◽

Antoine Nordez

Keyword(s):

Elastic Properties ◽

Gastrocnemius Muscle ◽

Medial Gastrocnemius ◽

Muscle Belly ◽

Supersonic Shear Imaging ◽

Medial Gastrocnemius Muscle

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Acute Effects of Static Stretching on Muscle Hardness of the Medial Gastrocnemius Muscle Belly in Humans: An Ultrasonic Shear-Wave Elastography Study

Ultrasound in Medicine & Biology ◽

10.1016/j.ultrasmedbio.2014.03.024 ◽

2014 ◽

Vol 40 (9) ◽

pp. 1991-1997 ◽

Cited By ~ 56

Author(s):

Masatoshi Nakamura ◽

Tome Ikezoe ◽

Takuya Kobayashi ◽

Hiroki Umegaki ◽

Yohei Takeno ◽

...

Keyword(s):

Shear Wave ◽

Gastrocnemius Muscle ◽

Shear Wave Elastography ◽

Medial Gastrocnemius ◽

Static Stretching ◽

Acute Effects ◽

Muscle Belly ◽

Muscle Hardness ◽

Ultrasonic Shear ◽

Medial Gastrocnemius Muscle

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Modelling the pressure and force equilibrium in unipennate muscles with in-line tendons

Philosophical Transactions of the Royal Society B Biological Sciences ◽

10.1098/rstb.1993.0162 ◽

1993 ◽

Vol 342 (1302) ◽

pp. 321-333 ◽

Cited By ~ 28

Keyword(s):

Negative Curvature ◽

Gastrocnemius Muscle ◽

Mechanical Stability ◽

Positive Curvature ◽

Medial Gastrocnemius ◽

Outer Side ◽

Muscle Fibres ◽

Muscle Belly ◽

Medial Gastrocnemius Muscle ◽

Force Equilibrium

Several of the models proposed in the literature of unipennate muscles, which have two tendinous sheets and in-line tendons, cannot meet the criterion of mechanical stability. Based on the theory of Van Leeuwen & Spoor ( Phil. Trans. R. Soc. Lond. B 336, 275-292 (1992)), we discuss how mechanically stable solutions for (planar) unipennate architectures could be obtained. A mathematical model is proposed in which the muscle architecture is generated numerically using the principles of mechanical stability and assuming that all muscle fibres shorten by the same relative amount. The tendinous sheets are attached tangentially to their respective tendons, as predicted from their low bending stiffness. The curvature, however, is discontinuous at the junction because of the sudden absence of muscle fibres from aponeurosis to tendon. In two of the muscle shapes generated, the sheets adjacent to the tendon show a region of negative curvature connected to a region of positive curvature. A sheet with a concave outer side is defined to have a negative curvature. In another example, two negative curvature regions are present with a positive region in-between. We show also a generated shape with a negative curvature of the sheets over their whole length. A good resemblance was found between the unipennate medial gastrocnemius muscle of the cat and a simulated architecture. The pressure distribution has also been calculated. With all muscle fibres exerting the same tensile stress of 200 kPa, a high pressure region is present in the centre of the muscle belly, half-way along its length. The highest pressures are predicted for muscles with long tendinous sheets, large attachment angles, and strongly curved fibres. Maximum pressures (2.40, 9.54, 10.47, and 7.57 kPa for the four discussed examples, and 15.05 kPa for the simulated gastrocnemius muscle) were at the lower side of the range as predicted previously for bipennate muscles and the unipennate medial gastrocnemius muscle of man (Van Leeuwen & Spoor 1992).

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