Flashcards in Muscles of the Shoulder, Arm, Forearm, and Hand Deck (36):
The middle fibers of the deltoid muscle are involved in what type of movement?
Name the origin of the supraspinatus muscle.
Supraspinous fossa of the scapula
Where is the insertion of the trapezius muscle?
Acromion and spine of scapula; lateral one-third of clavicle
Does the biceps brachii muscle originate from or insert on to the scapula?
What is the insertion of the pectoralis minor?
Coracoid process of the scapula
Name the muscles that are that are the antagonists of the triceps brachii.
Biceps brachii and brachialis
What is the origin of the trapezius muscle?
Superior nuchal line of the occipital bone; nuchal ligament; spinous process of vertebrae C7-T3 or T4
Name the action(s) of the pectoralis major muscle.
Flexes, adducts, and medially rotates the humerus.
What is the origin of the pectoralis minor?
Sternal end of ribs 3 - 5
The latissimus dorsi muscle has what action(s)?
Adducts and medially rotates the humerus; produces backward swinging of the arms (extension/hypextension)
Which "axial" muscle flexes, adducts, and medially rotates the humerus?
The pectoralis major muscle
Name the area of insertion for the infraspinatous muscle.
The greater tubercle of the humerus
Name the four shoulder muscles whose tendons form the rotator cuff.
Supraspinatus, Infraspinatus, Teres minor, and Subscapularis ("SITS" muscles)
What are the actions of the triceps brachii?
Prime move of elbow extension; extends and adducts arm
Which muscle is the prime mover for flexion of the elbow?
Name the origin of the brachialis muscle.
Anterior surface of the distal half of humerus
List the 5 forearm muscles that 'extend' the wrist.
POSTERIOR (EXTENSOR) COMPARTMENT
- Extensor Carpi Radialis (Longus and
- Extensor Digitorum
- Extensor Digiti Minimi
- Extensor Carpi Ulnaris
- Extensor Indicis [deep]
Name the 'prime mover' of elbow flexion.
Where is the origin of the flexor carpi radialis muscle?
Median epicondyle of humerus
Which muscles are the antagonists of the supinator muscle?
Pronator quadratus and Pronator teres
Where does the Extensor digitorum muscle insert?
Dorsal surfaces of phalanges II - V
What muscles are located at the base of the thumb?
The "thenar group" of intrinsic hand muscles, including the:
- Adductor pollicis
- Abductor pollicis brevis
- Flexor pollicis brevis
- Opponens pollicis
Which four muscles of the forearm "flex" the wrist?
- Flexor carpi radialis
- Flexor carpi ulnaris
- Flexor digitorum superficialis
- Flexor digitorum profundus [deep]
What muscles extend the thumb?
- Abductor pollicis longus
- Extensor pollicis longus
- Extensor pollicis brevis
The muscles acting on the pectoral girdle originate and insert where?
Originate on the axial skeleton and insert on the scapula and/or clavicle
The scapula is loosely attached to the thoracic cage which allows movements such as...
Rotation, elevation, depression, protection and retraction
What function does the clavicle serve in the pectoral girdle?
It braces the shoulder and moderates the movements of the scapula
The muscles acting on the shoulder are divided into which two groups?
Anterior and Posterior Thoracic Groups
Which axial muscles acting on the shoulder are in the Anterior Thoracic Group?
- Pectoralis Major
- Pectoralis Minor [deep]
- Serratus Anterior [deep]
Which axial muscles acting on the shoulder are in the Posterior Thoracic Group?
- Latissimus dorsi
- Rhomboid major
- Rhomboid minor
- Levator scapulae
Of the nine muscles that cross the shoulder joint and insert (act on) the arm, how many are axial [hint: they overlap with muscles that act on the shoulder]? Which muscles are they?
Two: the pectoralis major and latissimus dorsi.
Of the nine muscles that cross the shoulder joint and insert (act on) the arm, how many are scapular? What are they?
Seven: 4 "SITS" muscles which form the rotator cuff with their tendons, and also the deltoid, teres major and coracobrachialis.
What movements are the muscles in the arm and forearm capable of producing at the elbow?
Flexion, extension, pronation, and supination
How many muscles that act on the forearm, wrist and hand have their bellies in the forearm (antebrachium)?
Five: two that are synergists in elbow flexion/extension [brachioradialis (anterior) and anconeus (posterior), respectively]; two that function in pronation of the forearm anteriorly (pronator quadratus and pronator teres); and one that functions in supination posteriorly (the supinator).
Of the muscles that act on the forearm and have their bellies in the arm (brachium), which are the principal flexors are located on the anterior side of the humerus?
Brachialis (prime mover) and biceps brachii.