Muscular System Gross Anatomy

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Muscular SystemGross Anatomy

• Chapter 10

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General Principles

• Tendons Attach muscles to bones
• Aponeurosis A very broad tendon
• Muscles
• Origin or head Muscle end attached to more
  stationary of two bones
• Insertion Muscle end attached to bone with
  greatest movement
• Belly Largest portion of the muscle between
  origin and insertion
• Synergists Muscles that work together to cause a
  movement
• Prime mover Plays major role in accomplishing
  movement
• Agonist Muscle causing an action when contracts
• Antagonist A muscle working in opposition to
  agonist
• Fixators Stabilize joint/s crossed by the prime
  mover

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Muscle Shapes
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Muscle Shapes
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Nomenclature

• Muscles are named according to
• Location pectoralis gluteus, brachial
• Size maximus, minimus, longus, brevis
• Shape deltoid, quadratus, teres
• Orientation rectus
• Origin and insertion sternocleidomastoid,
  brachioradialis
• Number of heads biceps, triceps
• Function abductor, adductor, masseter

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Muscle Movements

• Muscle contractions are a pull or force by
  relative positions of
• Lever Rigid shaft or bone
• Fulcrum Pivot point or joint
• Weight or resistance

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Classes of Levers

• Class I
• Fulcrum between force and weight
• Seesaw or head movement
• Class II
• Weight is between fulcrum and pull
• Wheelbarrow, standing on toes
• Class III
• Pull located between fulcrum and weight
• Person using a shovel
• Most common

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Muscle Anatomy Anterior View
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Muscle Anatomy Posterior View
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Muscles of the Neck
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Muscles of Facial Expression
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Muscles of Mastication
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Muscles of Respiration
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Muscles of the Abdominal Wall
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Muscles of Pelvic Floor and Perineum
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Muscles of the Arm
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Muscles of the Forearm
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Muscles of the Thigh
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Muscles of the Leg
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Muscles of the Leg
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Muscles of the Foot