Musculoskeletal Geometry, Muscle Architecture and Functional Specialisations of the Mouse Hindlimb.
Mice are one of the most commonly used laboratory animals, with an extensive array of disease models in existence, including for many neuromuscular diseases. The hindlimb is of particular interest due to several close muscle analogues/homologues to humans and other species. A detailed anatomical study describing the adult morphology is lacking, however. This study describes in detail the musculoskeletal geometry and skeletal muscle architecture of the mouse hindlimb and pelvis, determining the extent to which the muscles are adapted for their function, as inferred from their architecture. Using I2KI enhanced microCT scanning and digital segmentation, it was possible to identify 39 distinct muscles of the hindlimb and pelvis belonging to nine functional groups. The architecture of each of these muscles was determined through microdissections, revealing strong architectural specialisations between the functional groups. The hip extensors and hip adductors showed significantly stronger adaptations towards high contraction velocities and joint control relative to the distal functional groups, which exhibited larger physiological cross sectional areas and longer tendons, adaptations for high force output and elastic energy savings. These results suggest that a proximo-distal gradient in muscle architecture exists in the mouse hindlimb. Such a gradient has been purported to function in aiding locomotor stability and efficiency. The data presented here will be especially valuable to any research with a focus on the architecture or gross anatomy of the mouse hindlimb and pelvis musculature, but also of use to anyone interested in the functional significance of muscle design in relation to quadrupedal locomotion.
Neuromuscular Diseases Group, Comparative Biomedical Sciences, Royal Veterinary College, 4 Royal College Street, London, NW1 0TU, United Kingdom.|Structure and Motion Lab, Comparative Biomedical Sciences, Royal Veterinary College, Hawkshead Lane, Hatfield, Hertfordshire, AL9 7TA, United Kingdom.
James P
JP
Charles
Neuromuscular Diseases Group, Comparative Biomedical Sciences, Royal Veterinary College, 4 Royal College Street, London, NW1 0TU, United Kingdom.
Ornella
O
Cappellari
Structure and Motion Lab, Comparative Biomedical Sciences, Royal Veterinary College, Hawkshead Lane, Hatfield, Hertfordshire, AL9 7TA, United Kingdom.|Department of Bioengineering, College of Engineering, Temple University, 1947 N. 12th Street, Philadelphia, PA 19122, United States of America.
Andrew J
AJ
Spence
Structure and Motion Lab, Comparative Biomedical Sciences, Royal Veterinary College, Hawkshead Lane, Hatfield, Hertfordshire, AL9 7TA, United Kingdom.
John R
JR
Hutchinson
Neuromuscular Diseases Group, Comparative Biomedical Sciences, Royal Veterinary College, 4 Royal College Street, London, NW1 0TU, United Kingdom.
Dominic J
DJ
Wells
D000222:Adaptation, Physiological; D000818:Animals; D005260:Female; D006614:Hindlimb / Q000033:anatomy & histology* / Q000000981:diagnostic imaging / Q000502:physiology*; D021621:Imaging, Three-Dimensional; D051379:Mice; D008810:Mice, Inbred C57BL; D018482:Muscle, Skeletal / Q000033:anatomy & histology* / Q000000981:diagnostic imaging / Q000502:physiology*; D009142:Musculoskeletal Physiological Phenomena; D009141:Musculoskeletal System / Q000033:anatomy & histology / Q000000981:diagnostic imaging; D055114:X-Ray Microtomography