2017 Muscles list and actions PDF

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Summary

Muscles list and actions...

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A & P II getbodysmart.com Muscles that Control the Neck & promote swallowing figs: 13.5, 13.9

Muscles

Muscles that Control the Shoulder figs: 13.15, 13.9, 13.6 & stabilize the scapula during arm movements

D.M. Hall & R Kinsinger

Muscles that Control the Wrist & Hand Fig: 13.11

Sternocleidomastoid______

Trapezius______

Pronator Teres______

Semispinalis capitis______

Deltoid______

Flexor Carpi Radialis______

Sternohyoid______

Infraspinatus______

Flexor Carpi Ulnaris______

Omohyoid______

Supraspinatus ______

Flexor Digitorum______

Teres Minor______

Extensor Carpi Radialis______

Muscles that Control the Thorax & Abdomen (trunk) & promote respiration figs: 13.5 - 13.9

Subscapularis ______

Extensor Carpi Ulnaris______

Pectoralis Minor __________

Latissimus Dorsi ______

Extensor Digitorum______

External Abdominal Obliques ______

Pectoralis Major______

Muscles that Control the Hip & Knee Fig: 13.12, 13.13

Internal Abdominal Obliques______

Muscles that Control the Elbow Figs: 13.14

Sartorius______

External Intercostals______

Biceps Brachii ______

Internal Intercostals ______

Triceps Brachii______

Quadriceps: Rectus Femoris _________ Vastus Medialis______ Vastus Intermedius______ Vastus Lateralis______

Rectus Abdominis______

Brachialis______

Scalenes______

Brachioradialis______

Erector spinae______

Muscles that Control the Foot & Ankle Figs: 13.14, 13.15

Hamstrings: Biceps Femoris______ Semimembranosus______ Semitendinosus______ Gracilis______

Tibialis Anterior______

Gluteus Maximus______

Gastrocnemius______

Adductor Longus______

Soleus______

Gluteus Medius______

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A & P II getbodysmart.com

Muscles

D.M. Hall & R Kinsinger

Muscles that Control the Neck Name Sternocleidomastoid

Major actions Prime mover of head flexion against resistance (raise head while lying down). Acting alone, rotates head toward opposite shoulder

Semispinalis Capitis

Extends vertebral column & head; rotates to opposite side

Special function: swallowing & speech Sternohyoid

Pulls hyoid bone down during swallowing & speech

Omohyoid

Pulls hyoid bone down during swallowing & speech

Muscles that Control the Thorax & Abdomen Abdominal Obliques (ext. & int.)

Compression of abdomen (forced exhalation, vomiting). Acting individually, produces trunk rotation & lateral flexion.

Rectus Abdominus

Compression of abdomen. Prime mover in trunk flexion. Rotates lumbar region. Stabilizes pelvis during walking.

Erector Spinae

(includes Iliocostalis, Longissimus, and Spinalis) Prime mover of back extension. Important postural muscles.

Special function: respiration External Intercostals

Elevate & expand rib cage during inspiration (bucket handle effect). Aids in inspiration.

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A & P II getbodysmart.com

Internal Internalcostals

Muscles

Draw the ribs together to depress ribcage during forced expiration

Scalenes (middle, anterior, posterior) Pectoralis Minor

D.M. Hall & R Kinsinger

Flex & slightly rotate the head, elevate ribs 1 & 2, aids in inspiration

With ribs fixed, draws scapula forward and down (pointing the shoulder forward); with scapula fixed, draws rib cage superiorly. Important as an accessory muscle of inspiration as it can elevate ribs 3, 4, & 5

Muscles that Control the Shoulder Name

Major actions

Deltoid

Prime mover of arm abduction. Anterior fibers flex and rotate humerus medially; posterior fibers extend and laterally rotate arm. Active during rhythmic movements like swinging arms while walking.

Latissimus Dorsi

Prime mover of arm extension. Powerful arm adductor. Medially rotates arm at the shoulder. Important in movements like hammering, swimming, rowing and pull-ups.

Pectoralis Major

Prime mover of arm flexion, rotates arm medially, adducts arm against resistance. Assists in: climbing throwing, pushing, & forced inspiration

Infraspinatus

Rotates arm laterally Stabilizes shoulder joint.

Supraspinatus

Initiates abduction of humerus, stabilizes the shoulder joint

Teres Minor

Lateral rotation of the humerus, stabilizes the shoulder joint

Subscapularis

Medially rotates the humerus, stabilizes the shoulder

Rotator cuff muscles (SITS)

Special function: stabilize scapula for all movements – must lock scapula for other movements Trapezius

Stabilizes, raises, retracts, & rotates the scapula. Assists in all movements utilizing the shoulder girdle.

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A & P II getbodysmart.com

Muscles

D.M. Hall & R Kinsinger

Muscles that Control the Elbow Name Biceps Brachii Brachialis Brachioradialis Triceps Brachii

Major actions Prime mover of forearm flexion & a powerful forearm supinator Moves the radius during flexion and when I uncork my bottle of wine Flexion of forearm (lifts ulna as biceps lifts radius) Moves the ulna during flexion Flexion of forearm. Important when elbow is flexed & wrist is semi-pronated (hammering). Used to pronate & fix the forearm when hammering a nail Prime mover of forearm extension.

Muscles that Control the Wrist & Hand Pronator Teres

Pronates forearm

Flexor Carpi Radialis

Powerful flexor & abductor of the hand.

Flexor Carpi Ulnarus

Flexes & adducts the hand.

Flexor Digitorum

Flexes wrist and digits 2-5

Extensor Carpi radialis

Extends and abducts the hand

Extensor Carpi Ulnarus

Extends & adducts the wrist

Extensor digitorum

Prime mover of finger extension. Can flare the fingers.

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A & P II getbodysmart.com

Muscles

D.M. Hall & R Kinsinger

Muscles that Control the Hip & Knee Name

Major actions

Sartorius

Longest muscle in the body. Crosses both hip & knee joints. Flexes, abducts, & laterally rotates thigh (cross legs while sitting)

Adductor longus

Adducts, flexes, & medially rotates thigh

Gracilis

Adducts, flexes, and medially rotates thigh.

Quadriceps Femoris  Rectus Femoris  Vastus lateralis  Vastus medialis  Vastus intermedius

Powerful hip flexor & prime mover of knee extension. Important is knee joint stability. Used in climbing, jumping, running, rising from seated position

Hamstrings   

important walking muscles

Crosses both hip & knee joints. Prime movers of thigh extension & knee flexion.

Biceps Femoris Semitendinosus Semimembranosus

Gluteus maximus

Power extension of thigh. Generally inactive in walking & standing. Important in thrusting/extension movements (climbing stairs, running).

Gluteus medius

Abducts and medially rotates thigh. Extremely important in walking, as it steadies the pelvis on the side of the planted leg allowing the trailing foot to clear ground. Prevents pelvic sag.

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A & P II getbodysmart.com

Muscles

D.M. Hall & R Kinsinger

Muscles that Control the Foot & Ankle Tibialis Anterior Gastrocnemius Soleus

Prime mover of dorsiflexion. Inversion of foot. Prime mover of ankle plantar flexion Crosses both knee & ankle joints. Assists in knee flexion. Prime mover of ankle plantar flexion Important locomotor & postural muscle (walking, running, dancing)

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