Transcript Muscle attachments

Attachment of muscles
Muscles are attached to bones or
other structures either directly or
indirectly
Direct/Indirect attachment
Direct--Epimysium of muscle is fused to bone or
cartilage
Indirect—muscle fascia extends beyond the
muscle as a tendon and connects to either
bone, cartilage, or fascia of another muscle
Arrangement of Fascicles
• The way the muscles are arranged influences
the range of motion and the amount of power
• Power is dependent on the number of muscle
cells being used
• Muscle fibers can shorten to about ½ their
length
• Longer muscle fibers in the direction of the
muscle axis allow for a greater range of
motion
Parallel arrangement
• Long axis of the fascicle runs with the
longitudinal axis of the muscle
– Ex—strap-like muscles of the biceps
Pennate attachment
• Muscle fibers are short and fascicles are
attached at an angle to a central tendon
running the length of the muscle
• Unipennate—one side
• Bipennate—both sides
Convergent attachment
• Broad origin and fascicles converge (come
together) toward a central tendon-example is
the pectoralis major
Circular arrangement
• Fascicles form a circle around muscle fibers
• Ex—muscles around eyes and mouth