1. Muscles of the Body

2. Muscles of the Body Ligaments connect bone to bone
Tendons connect muscle to bone
The origin of a muscle is the attachment of a muscle’s tendon to the stationary bone
The insertion of a muscle is the attachment of the muscle’s other tendon to the moveable bone
In producing movement, bones act as levers and joints function as the fulcrums of these levers
Movement is produced by a mechanical advantage

3. Archimedes ( B.C.)
Scientist, mathematician, and engineer of ancient Greece
Invented a planetarium
Invented a hydraulic musical organ
Invented the Screw of Archimedes, which moved water uphill
Figured out while taking a bath how to tell whether King Hiero’s crown was made of gold, and ran naked through the streets shouting “Eureka!”
Invented a machine to lever ships between the dock and the water
“Give me a lever long enough, and a place to stand, and I will move the earth.”

4. Fascicle Arrangement

5. Learn How Muscles Are Named!

6. Learn How Muscles Are Named!

7. Muscles of Facial Expression
Orbicularis oris = kissing muscle
Occipitofrontalis (frontal belly) = surprise muscle
Zygomaticus major = smile muscle
Buccinator = whistling muscle
Orbicularis oculi = winking muscle
Corrugator supercilii = scowl muscle
Zygomaticus minor = snarl muscle
Mentalis = pout muscle
Risorius = grimace muscle
Botox!

8. Muscles That Move the Eyeballs
All rectus muscles originate on the common tendinous ring attached to orbit around optical foramen
Superior oblique originates on sphenoid
Inferior oblique originates on maxilla
All rectus muscles insert on the eyeball on the same side as their name
Oblique muscles insert on the eyeball between the adjacent rectus muscles

9. Muscles of the Head and Neck
Platysma depresses the mandible and also “pouts”
Occipitofrontalis (occipital belly) draws scalp posteriorly
Masseter elevates the mandible
Temporalis elevates and retracts the mandible
Medial pterygoid elevates and retracts the mandible
Lateral pterygoid depresses and protracts the mandible

10. Muscles of the Head and Neck
Digastric elevates the hyoid and depresses the mandible
Stylohyoid elevates the hyoid
Both originate at least in part on the temporal bone, and insert on the hyoid
Useful in speaking and swallowing
Omohyoid originates on the scapula and depresses the hyoid
Sternohyoid originates on the clavicle and sternum, and depresses the hyoid
Once again useful in speaking and swallowing

11. Muscles of the Head and Neck
Sternocleidomastoid laterally extends and rotates the head to the side opposite the muscle
Originates on the sternum and clavicle
Inserts on the mastoid process of the temporal bone

12. Muscles That Move the Shoulder Girdle
Trapezius (posterior): elevates and adducts the scapula
Levator scapulae (posterior): elevates and rotates scapula
Rhomboid major (posterior): elevates and adducts scapula
Pectoralis minor (anterior): abducts scapula, elevates ribs 3 - 5
Serratus anterior (anterior): abducts scapula, elevates ribs, the “boxer’s muscle”

13. Muscles That Move the Arm
Supraspinatus: assists in abducting the arm
Infraspinatus: laterally rotates and adducts arm
Subscapularis: medially rotates arm
Teres major: extends, adducts, and medially rotates arm
Teres minor: extends, adducts, and laterally rotates arm
Deltoid: abducts arm

14. Muscles That Move the Arm
Supraspinatus, infraspinatus, subscapularis, and teres minor form the rotator cuff
These muscles and their tendons form a cuff or sleeve around the shoulder joint
The supraspinatus is most commonly affected
The muscle tears, or suffers impingement of the tendon
Common in baseball players, swimmers, tennis players, and various workers

15. Muscles That Move the Arm
The rotator cuff

16. Muscles That Move the Arm
Pectoralis major: adducts and medially rotates the arm
Originates on the clavicle, sternum, and costal cartilages
Inserts on the humerus
Latissimus dorsi: extends, adducts, and medially rotates the arm
Originates on vertebrae, sacrum, ilium, and ribs
Inserts on the humerus

17. Muscles That Move the Forearm
Triceps brachii: extends forearm
Lateral and medial heads originate on the humerus
Long head originates on infraglenoid tubercle
Insert on the olecranon process of the ulna
Brachialis: flexes forearm
Originates on the humerus
Inserts on the ulna
Biceps brachii: flexes and supinates forearm
Short head originates on coracoid process of scapula
Long head originates on tubercle above glenoid cavity
Inserts on the radial tuberosity

18. Muscles That Move the Forearm
Supinator: supinates forearm
Originates on the lateral epicondyle of the humerus
Inserts on the radius
Pronator teres: pronates forearm
Originates on the medial epicondyle of the humerus
Brachioradialus: flexes the forearm, pronates and supinates back to neutral position
Originates on the humerus
Inserts on the radius

19. Muscles That Move the Wrist
Flexor digitorum superficialis, Flexor carpi radialis, Flexor carpi ulnaris, and Palmaris longis
All originate at least in part on the medial epicondyle of the humerus
All insert on the carpals or phalanges
Flexor pollicis longus flexes the thumb
It originates on the interosseous membrane and inserts on the thumb

20. Muscles That Move the Wrist
Extensor carpi radialis longus/brevis, Extensor carpi ulnaris, and Extensor digitorum all extend the hand and digits
All originate at least in part on the lateral epicondyle of the humerus
All insert on the metacarpals or phalanges
Abductor pollicis longus abducts the hand and thumb, and extends the thumb
It originates on the interosseous membrane and inserts on the first metacarpal

21. Muscles That Move the Wrist
Extensor pollicis longus/brevis extend the thumb and abduct the hand
Both originate at least in part on the interosseus membrane
Both insert on the thumb

22. Muscles of the Thorax
The diaphragm produces inhalation when it contracts, exhalation when it relaxes
It originates on the xiphoid process, as well as some vertebrae and ribs
It inserts on the central tendon

23. Muscles of the Thorax
Contraction of the external intercostals elevates the ribs during inhalation, relaxation depresses the ribs during exhalation
They originate on the inferior border of the rib above, and insert on the superior border of the rib below
Contraction of the internal intercostals draws the ribs together during exhalation
They originate on the superior border of the rib below, and insert on the inferior border of the rib above

24. Muscles That Move the Thigh
Psoas major and iliacus flex and rotate the thigh laterally
Both insert on the lesser trochanter of the femur
Tensor fasciae latae flexes and abducts the thigh
It originates on the iliac crest and inserts on the tibia
Pectineus flexes and adducts the thigh
It originates on the pubis and inserts on the femur
Adductor longus adducts and flexes the thigh
It originates on the pubis and ischium and inserts on the femur

25. Muscles That Move the Thigh
Adductor magnus adducts and laterally rotates the thigh
It originates on the ischium and pubis and inserts on the linea aspera of the femur
Gracilis adducts and medially rotates the thigh
It originates on the pubis and inserts on the tibia

26. Muscles That Move the Thigh
Gluteus maximus extends and laterally rotates the thigh
It originates on the iliac crest, sacrum, and coccyx
It inserts on the femur
Gluteus medius abducts and medially rotates the thigh
It originates on the ilium
It inserts on the greater trochanter of the femur

27. Muscles That Move the Leg
Sartorius flexes the leg, also flexes, abducts, and laterally rotates the thigh
It originates on the ilium and inserts on the tibia
Sartorius is the longest muscle in the body
Rectus femoris, vastus lateralis, vastus medialis, and vastus intermedius together form the quadriceps femoris, which extend the leg
All originate on the ilium or femur
All insert on the patella and the tibia

28. Muscles That Move the Leg
Biceps femoris flexes the leg and extends the thigh
The long head originates on the ischium and the short head on the femur
Inserts on the tibia and fibula
Semitendinosus and semimembranosus flex the leg and extend the thigh
Both originate on the ischial tuberosity
Both insert on the tibia
All three muscles together are known as the hamstrings

29. Muscles That Move the Foot
Tibialis anterior dorsiflexes and inverts the foot
It originates on the tibia and inserts on the first metatarsal and cuneiform
Soleus plantar flexes the foot
It originates on the fibula and tibia and inserts on the calcaneus
Fibularis longus/brevis (peroneus) plantar flex and evert the foot
Fibularis longus originates on the tibia and fibula and inserts on the first metatarsal and first cuneiform
Fibularis brevis originates on the fibula and inserts on the fifth metatarsal

30. Muscles That Move the Foot
Gastrocnemius plantar flexes the foot, and flexes the leg
It originates on the condyles of the femur and inserts on the calcaneus
Flexor digitorum longus plantar flexes the foot and flexes the toes
It originates on the tibia and inserts on the distal phalanges 2 - 5
Flexor hallucis longus plantar flexes the foot and flexes the great toe
It originates on the fibula and inserts on the great toe