Architecture and the Division of Labor in the Extensor carpi radialis Muscle of Horses

Hermanson, John W.

doi:10.1159/000147975

Cited by 26 publications

(24 citation statements)

References 2 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…This group also exhibited reduced vertical displacement while trotting compared with walking (Table 2). Such 'spring dampening' while loading the Achilles tendon at speed reduces damaging vibrations and enhances forward propulsion with subsequent energy savings (Alexander, 2001;Hermanson, 1997;Reilly et al, 2007;Wilson et al, 2000Wilson et al, , 2001, which is consistent with our metabolic measurements (Fig. 3).…”

Section: Discussionsupporting

confidence: 89%

Comparative locomotor costs of domestic dogs reveal energetic economy of wolf-like breeds

Bryce

Williams

2016

Journal of Experimental Biology

View full text Add to dashboard Cite

The broad diversity in morphology and geographic distribution of the 35 free-ranging members of the family Canidae is only rivaled by that of the domesticated dog, Canis lupus familiaris. Considered to be among nature's most elite endurance athletes, both domestic and wild canids provide a unique opportunity to examine the variability in mammalian aerobic exercise performance and energy expenditure. To determine the potential effects of domestication and selective breeding on locomotor gait and economy in canids, we measured the kinematics and mass-specific metabolism of three large (>20 kg) dog breed groups (northern breeds, retrievers and hounds) of varying morphological and genomic relatedness to their shared progenitor, the gray wolf. By measuring all individuals moving in preferred steady-state gaits along a level transect and on a treadmill, we found distinct biomechanical, kinematic and energetic patterns for each breed group. While all groups exhibited reduced total cost of transport (COT) at faster speeds, the total COT and net COT during trotting and galloping were significantly lower for northern breed dogs , respectively). These results suggest that, in addition to their close genetic and morphological ties to gray wolves, northern breed dogs have retained highly cursorial kinematic and physiological traits that promote economical movement across the landscape.

show abstract

Section: Discussionsupporting

confidence: 89%

Comparative locomotor costs of domestic dogs reveal energetic economy of wolf-like breeds

Bryce

Williams

2016

Journal of Experimental Biology

View full text Add to dashboard Cite

show abstract

“…Pennation angle in equine muscle has received less attention in the literature (Hermanson and Cobb, 1992;Hermanson, 1997). Pennation angle is important because highly pennated muscles typically have more short muscle fibers arranged in parallel.…”

Section: Discussionmentioning

confidence: 99%

“…The flexor carpi mm) and short (7-14 mm) fibers. Hermanson (1997) c noted 92 mm long fiber bundles in the proximal region of extensor carpi radialis, but did not quantify muscle fiber length within these bundles.…”

Section: Physiological Cross-section Area (Pcsa)mentioning

confidence: 97%

Architectural properties of distal forelimb muscles in horses,Equus caballus

Brown

Kawcak

McIlwraith

et al. 2003

Journal of Morphology

View full text Add to dashboard Cite

Articular injuries in athletic horses are associated with large forces from ground impact and from muscular contraction. To accurately and noninvasively predict muscle and joint contact forces, a detailed model of musculoskeletal geometry and muscle architecture is required. Moreover, muscle architectural data can increase our understanding of the relationship between muscle structure and function in the equine distal forelimb. Muscle architectural data were collected from seven limbs obtained from five thoroughbred and thoroughbred-cross horses. Muscle belly rest length, tendon rest length, muscle volume, muscle fiber length, and pennation angle were measured for nine distal forelimb muscles. Physiological cross-sectional area (PCSA) was determined from muscle volume and muscle fiber length. The superficial and deep digital flexor muscles displayed markedly different muscle volumes (227 and 656 cm3, respectively), but their PCSAs were very similar due to a significant difference in muscle fiber length (i.e., the superficial digital flexor muscle had very short fibers, while those of the deep digital flexor muscle were relatively long). The ulnaris lateralis and flexor carpi ulnaris muscles had short fibers (17.4 and 18.3 mm, respectively). These actuators were strong (peak isometric force, Fmax=5,814 and 4,017 N, respectively) and stiff (tendon rest length to muscle fiber length, LT:LMF=5.3 and 2.1, respectively), and are probably well adapted to stabilizing the carpus during the stance phase of gait. In contrast, the flexor carpi radialis muscle displayed long fibers (89.7 mm), low peak isometric force (Fmax=555 N), and high stiffness (LT:LMF=1.6). Due to its long fibers and low Fmax, flexor carpi radialis appears to be better adapted to flexion and extension of the limb during the swing phase of gait than to stabilization of the carpus during stance. Including muscle architectural parameters in a musculoskeletal model of the equine distal forelimb may lead to more realistic estimates not only of the magnitudes of muscle forces, but also of the distribution of forces among the muscles crossing any given joint.

show abstract

“…Many locomotor muscles in mammals are composed by "neuromuscular compartments," defined as nonoverlapping sections within the muscle, each innervated by an individual muscle nerve branch (English and Letbetter, 1982) and each containing motor unit territories with a unique array of physiological attributes (English et al, 1993). Many studies have reported a clear correspondence between neuromuscular partitions, muscle architectural designs, and muscle fiber type distribution (Burkholder et al, 1994;Hermanson, 1997;Gellman et al, 2002), suggesting an independence of motor control and division of labor between compartments. The term "muscle fiber type regionalization" is a newly developed concept that signifies the presence of regional intramuscular differences in fiber type composition (Kernell, 1998).…”

mentioning

confidence: 99%

Neuromuscular partitioning, architectural design, and myosin fiber types of the M. vastus lateralis of the llama (Lama glama)

Graziotti

Palencia

Delhon

et al. 2004

Journal of Morphology

View full text Add to dashboard Cite

The llama (Lama glama) is one of the few mammals of relatively large body size in which three fast myosin heavy chain isoforms (i.e., IIA, IIX, IIB) are extensively expressed in their locomotory muscles. This study was designed to gain insight into the morphological and functional organization of skeletal musculature in this peculiar animal model. The neuromuscular partitioning, architectural design, and myosin fiber types were systematically studied in the M. vastus lateralis of adult llamas (n = 15). Four nonoverlapping neuromuscular partitions or compartments were identified macroscopically (using a modified Sihler's technique for muscle depigmentation), although they did not conform strictly to the definitions of "neuromuscular compartments." Each neuromuscular partition was innervated by primary branches of the femoral nerve and was arranged within the muscle as paired partitions, two in parallel (deep-superficial compartmentalization) and the other two in-series (proximo-distal compartmentalization). These neuromuscular partitions of the muscle varied in their respective architectural designs (studied after partial digestion with diluted nitric acid) and myosin fiber type characteristics (identified immunohistochemically with specific anti-myosin monoclonal antibodies, then examined by quantitative histochemistry and image analysis). The deep partitions of the muscle had longer fibers, with lower angles of pinnation, and higher percentages of fast-glycolytic fibers than the superficial partitions of the muscle. These differences clearly suggest a division of labor in the whole M. vastus lateralis of llamas, with deep partitions exhibiting features well adapted for dynamic activities in the extension of stifle, whereas superficial portions seem to be related to the antigravitational role of the muscle in preserving the extension of the stifle during standing and stance phase of the stride. This peculiar structural and functional organization of the llama M. vastus lateralis does not confirm the generalized idea that deep muscles or the deepest portions within the same muscles somehow develop postural and/or low-intensity isometric functions. Rather, it suggests a primacy of architecture over intramuscular location in determining fiber type composition and hence division of labor within the muscle. A compartmentalization in the distribution of the three fast-subtype fibers (IIA, IIX, and IIB) also occurred, and this could also be relevant functionally, since these fiber types differed significantly in size (IIA < IIX < IIB), oxidative capacity (IIA > IIX > IIB), and capillarization (IIA = IIX > IIB). Furthermore, a typical spatial pattern in fiber type distribution was encountered in llama muscle (i.e., fiber types were consistently ranked in the order I --> IIA --> IIX --> IIB from the center to the periphery of fascicles), suggesting again peculiar and not well understood functional adaptations in these species.

show abstract

Architecture and the Division of Labor in the Extensor carpi radialis Muscle of Horses

Cited by 26 publications

References 2 publications

Comparative locomotor costs of domestic dogs reveal energetic economy of wolf-like breeds

Comparative locomotor costs of domestic dogs reveal energetic economy of wolf-like breeds

Architectural properties of distal forelimb muscles in horses,Equus caballus

Neuromuscular partitioning, architectural design, and myosin fiber types of the M. vastus lateralis of the llama (Lama glama)

Contact Info

Product

Resources

About