Anatomy of the Muscular System Anatomy & Physiology

Skeletal Muscle Structure Endomysium: connective tissue membrane that surrounds individual muscle fibers or cells Endomysium: connective tissue membrane that surrounds individual muscle fibers or cells Fascicles: groups of skeletal muscle fibers Fascicles: groups of skeletal muscle fibers Perimysium: connective tissue membrane surrounding fascicles Perimysium: connective tissue membrane surrounding fascicles Epimysium: connective tissue membrane around muscle as a whole Epimysium: connective tissue membrane around muscle as a whole

Skeletal Muscle Structure

Attachment to bones Tendons: strong touch cord Tendons: strong touch cord Aponeurosis: broad flat sheet of connective tissue Aponeurosis: broad flat sheet of connective tissue

Fascia Fibrous connective tissue surrounding the muscle organ & tendon Fibrous connective tissue surrounding the muscle organ & tendon

Attachment of Skeletal Muscles Origin: point of attachment that doesn’t move when muscle contracts Origin: point of attachment that doesn’t move when muscle contracts Insertion: point of attachment that moves when muscles contract Insertion: point of attachment that moves when muscles contract

Muscle Actions Agonist (prime mover) Agonist (prime mover) Antagonist Antagonist Synergist Synergist Fixator Fixator

Agonist and antagonist Agonist: muscle or group of muscles that that directly perform a specific movement Agonist: muscle or group of muscles that that directly perform a specific movement Antagonist: muscles that oppose a prime mover or agonist. Relaxed when agonist when contracts Antagonist: muscles that oppose a prime mover or agonist. Relaxed when agonist when contracts

Synergist & Fixator Synergists: muscles that contract at the same time as the prime mover. They complement prime mover actions. Synergists: muscles that contract at the same time as the prime mover. They complement prime mover actions. Fixator: generally function as joint stabilizers. Serve to maintain posture or balance. Fixator: generally function as joint stabilizers. Serve to maintain posture or balance.

How muscles are named Location: biceps, brachii Location: biceps, brachii Function: adductor, longus Function: adductor, longus Shape: trapezius Shape: trapezius Direction of fibers: rectus, abdominus Direction of fibers: rectus, abdominus Number of heads: biceps, brachii Number of heads: biceps, brachii Points of attachment: sternocleidomastoid Points of attachment: sternocleidomastoid Size: gluteus, maximus Size: gluteus, maximus

GO TO: Muscle labeling slides GO TO: Muscle labeling slides

Muscles of the Head Muscles of facial expression Muscles of facial expression Occipitofrontalis #6 Occipitofrontalis #6 Orbicularis oris #4 Orbicularis oris #4 Orbicularis oculi #2 Orbicularis oculi #2 Zygomaticus #3 Zygomaticus #3 Buccinator Buccinator Muscles of Mastication Muscles of Mastication Massester #15 Temporalis #1

Muscles of the Neck Sternocleidomastoid #16 front view Sternocleidomastoid #16 front view Trapezius #6 back view Trapezius #6 back view

Muscles of the Thorax Internal intercostals Internal intercostals External intercostals External intercostals Diaphragm Diaphragm

Muscles of the Abdominal Wall External oblique #17 front External oblique #17 front Internal oblique #9 front Internal oblique #9 front Tranversus abdominus Tranversus abdominus Rectus abdominus #8 front Rectus abdominus #8 front

Muscles of the Abdominal Wall

Biceps brachii Flexes forearm Flexes forearm # 7 front view # 7 front view

Triceps brachii Extends the lower arm Extends the lower arm #8 back view #8 back view

Pectoralis #5 front view #5 front view

Deltoids #6 front view #6 front view

Serratus anterior #23 front view #23 front view

Teres major #12 back view #12 back view

Brachialis

Pronator # 24, front view # 24, front view

Bachioradialis #25 front view #25 front view

Flexor carpi ulnaris

Flexor carpi radialis #26 front view #26 front view

Gluteus maximus #1, back view

Gluteus medius #11 back view #11 back view

Pectineus #27 front view #27 front view

Gracilis #11 front view #11 front view

Sartorius #12 front view #12 front view

Adductor magnus #2 back view #2 back view #10 front view #10 front view

Rectus femoris #19 front view #19 front view

Vastus lateralis #20 front view #20 front view

Vastus medialis #21 front view #21 front view

Vastus intermedius

Biceps femoris #3 back view #3 back view

Semimembranosus

Semitendinosus #4 back view #4 back view

Peroneus #22 front view #22 front view

Tibialis anterior #13 front view #13 front view

Soleus #13 back view #13 back view

Gastrocnemius #5 back view #5 back view

Image Citations Slide 3: Structure of skeletal muscle, 11/5/06, Slide 3: Structure of skeletal muscle, 11/5/06, Slide 4, 8, 13: Slide 4, 8, 13: Slide 6: muscle, 11/5/06, Notes%20J%20Anatomy%20of%20a%20Muscle.htm Slide 6: muscle, 11/5/06, Notes%20J%20Anatomy%20of%20a%20Muscle.htm Notes%20J%20Anatomy%20of%20a%20Muscle.htm Notes%20J%20Anatomy%20of%20a%20Muscle.htm Slide 17: Biceps brachii, 11/5/06, d004.htm Slide 17: Biceps brachii, 11/5/06, d004.htm d004.htm d004.htm Slide 18: Triceps brachii, 11/5/06, Slide 18: Triceps brachii, 11/5/06, Slide 19: Pectoralis major, 11/5/06, Slide 19: Pectoralis major, 11/5/06,

Image Citations Slide 20: Deltoids, 11/5/06, ells/Muscle/Kids%20Muscles/Shoulder/Shoulder.htm Slide 20: Deltoids, 11/5/06, ells/Muscle/Kids%20Muscles/Shoulder/Shoulder.htm ells/Muscle/Kids%20Muscles/Shoulder/Shoulder.htm ells/Muscle/Kids%20Muscles/Shoulder/Shoulder.htm Slide 21: Serratus anterior, 11/5/06, C4%99baty_przedni Slide 21: Serratus anterior, 11/5/06, C4%99baty_przedni C4%99baty_przedni C4%99baty_przedni Slide 22: Teres major, 11/5/06, tomy1.htm Slide 22: Teres major, 11/5/06, tomy1.htm tomy1.htm tomy1.htm Slide 23: Brachialis, 11/5/06, brachial_anterieur.htm Slide 23: Brachialis, 11/5/06, brachial_anterieur.htm brachial_anterieur.htm brachial_anterieur.htm Slide 24: Pronator teres, 11/5/06, Slide 24: Pronator teres, 11/5/06,

Image Citations Slide 25 & 26: Brachioradialis, 11/5/06, Notes%20J%20%20Muscles%20of%20the%20Arm.htm Slide 25 & 26: Brachioradialis, 11/5/06, Notes%20J%20%20Muscles%20of%20the%20Arm.htm Notes%20J%20%20Muscles%20of%20the%20Arm.htm Notes%20J%20%20Muscles%20of%20the%20Arm.htm Slide 27: Flexor carpi radialis, 11/5/06, Notes%20J%20%20Muscles%20of%20the%20Arm.htm Slide 27: Flexor carpi radialis, 11/5/06, Notes%20J%20%20Muscles%20of%20the%20Arm.htm Notes%20J%20%20Muscles%20of%20the%20Arm.htm Notes%20J%20%20Muscles%20of%20the%20Arm.htm Slide 28: Gluteal muscles, 11/5/06, ml Slide 28: Gluteal muscles, 11/5/06, ml ml ml Slide 29: Gluteus medius, 11/5/06, ml Slide 29: Gluteus medius, 11/5/06, ml ml ml Slide 30: Diagram of pectineus m, 11/5/06, cywebsite/pectineus1.html Slide 30: Diagram of pectineus m, 11/5/06, cywebsite/pectineus1.html cywebsite/pectineus1.html cywebsite/pectineus1.html

Image Citations Slide 31: Anterior hip muscles, 11/5/06, Slide 31: Anterior hip muscles, 11/5/06, Slide 32: Sartorius, 11/5/06, Slide 32: Sartorius, 11/5/06, Slide 33: Adductor magnus and longus, 11/5/06, Slide 33: Adductor magnus and longus, 11/5/06, Slide 34: Rectus femoris, 11/5/06, tm Slide 34: Rectus femoris, 11/5/06, tm tm tm Slide 35: Vastus lateralis, 11/5/06, b2page.cfm?vbcid=6645&vid=1110 Slide 35: Vastus lateralis, 11/5/06, b2page.cfm?vbcid=6645&vid= b2page.cfm?vbcid=6645&vid= b2page.cfm?vbcid=6645&vid=1110 Slide 36: Vastus medialis, 11/5/06, tm Slide 36: Vastus medialis, 11/5/06, tm tm tm

Image Citations Slide 37: Vastus intermedius, 11/5/06, Slide 37: Vastus intermedius, 11/5/06, Slide 38: Biceps femoris, 11/5/06, Slide 38: Biceps femoris, 11/5/06, Slide 39: Hamstring muscles, 11/5/06, Slide 39: Hamstring muscles, 11/5/06, Slide 40: Semitendinosus, 11/5/06, %20%20Muscles%20of%20the%20Leg.htm Slide 40: Semitendinosus, 11/5/06, %20%20Muscles%20of%20the%20Leg.htm %20%20Muscles%20of%20the%20Leg.htm %20%20Muscles%20of%20the%20Leg.htm Slide 41: Peroneus, 11/5/06, anatomy/GR/peroneus.l.GIF Slide 41: Peroneus, 11/5/06, anatomy/GR/peroneus.l.GIF anatomy/GR/peroneus.l.GIF anatomy/GR/peroneus.l.GIF Slide 42: diagram of tibialis anterior, 11/5/06, Slide 42: diagram of tibialis anterior, 11/5/06,

Image Citations Slide 43: soleus, 11/5/06, 003/unit_8.htm Slide 43: soleus, 11/5/06, 003/unit_8.htm 003/unit_8.htm 003/unit_8.htm Gastrocnemius, 11/5/06, Gastrocnemius, 11/5/06,