jimtrue.com : school : APP : APP201: Upper Body Prime Movers [UBPM]

Posted by Jim True on January 23, 2007 10:37 PM. Last Updated February 9, 2007 12:19 AM

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APP201: Upper Body Prime Movers [UBPM]

Patterns of Muscle Orientation to Action

Elbow Joint

Elbow Flexors

Brachialis (Trail Guide p.140)

This muscle is on the anterior, distal end of the humerus and is DEEP. The name refers to the word "brach" which is the medical term for the upper arm.

Origin	Distal half of the anterior humerus
Insertion	Coronoid process
Primary Actions	Elbow Flexion
Other Actions	NONE
Comments	Primary elbow flexor when lifting LIGHT loads. Insertion on the ULNA, so the strength of brachialis is unaffected by rotational state of the radius, ie whether the forearm is pronated or supinated. Because the muscle only crosses one joint, it is difficult to effectively stretch.

Biceps brachii (p.103-104)

This muscle is on the anterior, upper arm and is superficial. The name refers to the term "brach" (upper arm) and Biceps means "Two Heads", referring to the two origins

Origin	Short Head: coracoid process of the scapula Long Head: Supraglenoid tubercle of the scapula; runs over the intertubercular groove.
Insertion	Radial Tuberosity
Primary Actions	Elbow Flexion, Supination
Other Actions	Shoulder Flexion
Comments	Biceps brachii contributes to actions at three separate joints (shoulder, elbow, proximal radioulnar). Primary mover for supination and becomes the prime mover for elbow flexion when there is heavy load of resistance.

Brachioradialis (p.141)

This muscle is on the forearm and is superficial. The name refers to the term "brach", which is where it originates, and to the radius bone, where it inserts.

Origin	Lateral supracondylar ridge of humerus, proximal to lateral epicondyle.
Insertion	Immediately proximal to Styloid process of the radius
Primary Actions	Elbow FLEXION
Other Actions	Pronates and Supinates to mid-position from an extreme rotated position.
Comments	Aids in Elbow Flexion; Especially effective when quick bursts of activity occur as in playing drums or performing tapotement.

Elbow Extensors

Triceps brachii (p.105-106)

This muscle is on the posterior upper arm and is superficial. The name refers to the term "brach", which is where it is located and triceps refers to its three origins.

Origin	Long Head: infraglenoid tubercle of the scapula Lateral Head: posterolateral aspect of humerus, inferior to the head Medial Head: posteromedial aspect of humerus, inferior to the head
Insertion	Olecranon process
Primary Actions	Elbow Extension and Shoulder Extension
Other Actions	Shoulder Adduction
Comments	Triceps brachii is the prime mover for elbow extension. It appears as a two-headed muscle of the posterior humerus because the medial head is DEEP to the long and lateral heads. The long head of triceps crosses the shoulder joint and the elbow joint. This allows it to contribute to shoulder extension and to shoulder adduction.

Radioulnar Joints (forearm)

Pronators

Pronator teres (p.154)

Pronator means 'pronates'; 'teres' means tube like or cylindrical

Origin	Medial epicondyle of the humerus
Insertion	Lateral surface of the radius; 1/3 the distance between the lateral epicondyle and the styloid process.
Primary Actions	Pronation
Other Actions	Elbow flexion, but REAL weak.
Comments	Pronator teres is the prime mover for rapid pronation and pronation against resistance. If you are right handed, this muscle would be used when loosening a screw with a screwdriver. For this muscle to effectively pronate, the elbow needs to be slightly flexed. notice your natural tendency to flex the elbow when effort is needed to pronate.

(Brachioradialis)

Supinators

(Biceps brachii)
Supinator (p.155-156)

Lateral aspect of the radius; it can be hard to find.

Origin	Lateral epicondyle of humerus and the posterolateral proximal ulna, distal to the olecranon
Insertion	Proximal 1/3 of anterolateral radius, ending proximal to the pronator teres insertion.
Primary Actions	Supination
Other Actions	NONE
Comments	Agonist to biceps brachii for the act of supination. This is a muscle that lies deep to brachioradialis and the wrist extensors. Supinator is sometimes involved in the entrapment of the deep branch of the radial nerve which passes through it. Symptoms generally include pain in forearm, hand and sometimes the shoulder.

(Brachioradialis)

Radiocarpal Joint (wrist)

Wrist Flexors: All FOREARMS flexors originate on the Medial Epicondyle

Flexor carpi radialis (p.149)

Insertion on the radial side of the wrist. Radialis refers to its location on top of the radius. ALL FOREARM flexors originate on the Medial epicondyle.

Origin	Medial epicondyle of the humerus
Insertion	The base of the 2nd and 3rd metacarpals
Primary Actions	Wrist flexion, and wrist abduction
Other Actions	NONE
Comments	Golfer's elbow, nickname for pain at the medial epicondyle.

Flexor carpi ulnaris (p.149) [FCU]

Origin	Medial epicondyle of the humerus.
Insertion	The pisiform and the base of the 5th metacarpal
Primary Actions	Wrist flexion, and wrist adduction
Other Actions	NONE
Comments

Palmaris longus (p.148-151)

Superficial on the anterior aspect of the forearm, because it's between the Flexor carpi radialis and ularnis, it can't contribute to flexion.

Comments

Origin	Medial epicondyle of the humerus
Insertion	The palmar aponeurosis (sheet of connective tissue).
Primary Actions	Wrist flexion
Other Actions	Cupping of the hand.

Flexor Digitorum (p.151 & 153)

Anterior forearm. Actually TWO different muscles, Flexor digitorum superficialis and Flexor digitorum profundis. FD profundis is DEEP to FD superficialis and both are deep to the remaining wrist flexors.

Origin	superficialis: medial epicondyle, the coronoid process and the shaft of the radius profundus: the proximate 3/4 of the
Insertion	superficialis: proximal middle phalanges of fingers 2-5 profundis: proximal distal phalanges of fingers 2-5
Primary Actions	flexion of fingers 2-5
Other Actions	wrist flexion
Comments

Wrist Extensors: Forearm extensors originate on the LATERAL epicondyle. They will all be posterior in anatomical position.

Extensor carpi ulnaris p.143-146

Origin	Lateral epicondyle of the humerus, posterior proximal ulna
Insertion	Base of the 5th metacarpal on the back of the hand.
Primary Actions	Wrist extension, wrist adduction
Other Actions	NONE
Comments	Tennis elbow.

Extensor Digitorum (p.143-146)

Origin
Insertion
Primary Actions
Other Actions
Comments

Extensor carpi radialis (p.143-146)

Origin	Brevis: lateral epicondyle of the humerus Longus: lateral supracondylar ridge of humerus, distal to the origin of brachioradialis
Insertion
Primary Actions
Other Actions
Comments

Wrist adductors (ulnar deviators)

(Flexor carpi ulnaris)
(Extensor carpi ulnaris)

Wrist abductors (radial deviators)

(Flexor carpi radialis)
(Extensor carpi radialis (brevis & longus))

Glenohumeral Joint (Shoulder)

Shoulder Flexors

Anterior Deltoid (p.75-76)

Origin	Lateral third of the clavicle
Insertion	Deltoid tuberosity of the humerus
Primary Actions	Shoulder abduction, and medial rotation rotation of the shoulder
Other Actions	Shoulder flexion
Comments	All of the muscles we have done have been VERTICAL muscles; deltoid is almost at a 45 degree angle. They can now do DIFFERENT things. Muscles that insert &/or originate laterally tend to be ABDUCTORS. Horizontal muscles rotate (they cannot flex and extend); the deltoid being horizontal enough can rotate and flex. Medial on the body tend to be ADDUCTERS.

Pectoralis major (p.97-99)

Named for the location, Pectoral region of the body.

Origin	Sternal half of the clavicle, the sternum, and the costal portions of the upper seven ribs.
Insertion	Lateral ridge of the bicipital groove.
Primary Actions	Shoulder adduction and medial rotation of the shoulder
Other Actions	Flexion and horizontal adduction.
Comments	The portion of shoulder flexion that the Pec Major handles is from extreme shoulder extension to anatomical position. Breasts are attached to the posterior aspect of the Pec Major. Hypo means under; tonic means contraction; hypotonic means really really weak contraction.

Coracobrachialis (p.107)

Origin	Coracoid process
Insertion	Medial shaft of humerus almost directly opposite from the deltoid tuberosity.
Primary Actions	Shoulder flexion, shoulder adduction.
Other Actions
Comments	Nickname (armpit muscle)

(Biceps brachii)

Shoulder Extensors

Posterior Deltoid (p.75-76)

Medial Rotators will be on the front; lateral rotators will be on the back.

Origin	Inferior lip of the spine of the scapula
Insertion	Deltoid tuberosity of the humerus
Primary Actions	Shoulder abduction, lateral rotation of the shoulder
Other Actions	shoulder extension
Comments

Latissimus dorsi (p.79-81)

Name means 'really wide back muscle'

Origin	Spinous processes of T7-L5, the sacrum, the posterior iliac crest and the thoracolumbar aponeurosis. [aponeurosis is a sheet of connective tissue. For a muscle it's all tendon.
Insertion	Medial ridge of the bicipital groove.
Primary Actions	Shoulder extension and Shoulder adduction
Other Actions	Medial rotation of the shoulder.
Comments

Teres major (p.79-81)

Teres is tube-like

Origin	Dorsal surface of the inferior angle and the lower axillary border of the scapula.
Insertion	Medial ridge of the bicipital groove just inferior to the insertion of latissimus dorsi
Primary Actions	Shoulder extension and shoulder adduction
Other Actions	Medial rotation of the shoulder.
Comments	Referred to as the 'little brother' of Latissimus Dorsi.

Shoulder Abductors

Middle Deltoid (p.75-76)

Origin	Outer aspect of the acromion process of the scapula
Insertion	Deltoid tuberosity
Primary Actions	Shoulder abduction
Other Actions	None
Comments

Supraspinatus p.82-86

Origin	Supraspinous fossa of the scapula
Insertion	Superior aspect of the greater tubercle of the humerus
Primary Actions	Stabilize the shoulder joint
Other Actions	Shoulder abduction
Comments	One of FOUR Rotator cuff muscles that help stabilize the shoulder joint, mainly by holding the head of the humnerus within the glenoid cavity, preventing dislocation. RULE: when you are on the top of the bone, you cannot rotate even though the muscle is horizontal because it is not anterior or posterior. Nickname for the Rotator cuff are SITS (Supraspinatus, Infraspinatus, Teres minor, Subscapularis). REMEMBER the FOUR ROTATOR CUFF muscles.

Subscapularis(p.82-86)

Named for it's location

Origin	Subscapular fossa of the scapula. (anterior to the scapula)
Insertion	Lesser tubercle of the humerus (anterior of the humerus)
Primary Actions	Stabilize the shoulder joint.
Other Actions	Medial rotation of the shoulder.
Comments	Second rotator cuff muscle. It is the only one that does medial rotation, and the only one to insert on the lesser tubercle of the humerus. Subscapularis is often a secondary factory in frozen shoulder. Frozen shoulder is a condition tha occurs as a result of the ligamentous joint capsule becoming fibrous, inflamed and adhere to adjacent structures or even itself.

Infraspinatus (p.82-86)

Origin	Infraspinous fossa of the scapula
Insertion	Posterior aspect of the greater tubercle of the humerus (posterior)
Primary Actions	Stabilize the shoulder joint.
Other Actions	Lateral rotation of the shoulder.
Comments	This is our third rotator cuff muscle. It helps stabilize the shoulder joint, mainly by holding the head of the humerus within the glenoid cavity, preventing dislocation. These muscles are nicknamed the SITS muscles

Teres minor (p.82-86)

Origin	Middle third of the axillary border (lateral border) of the scapula.
Insertion	Greater tubercle INFERIOR to the insertion for the infraspinatus.
Primary Actions	Stabilize the shoulder
Other Actions	Lateral rotation of the shoulder.
Comments	Agonist to Infrapinatus.

Shoulder Adductors
Shoulder Medial Rotators
Shoulder Lateral Rotators

Shoulder Girdle

Scapular Protraction

Serratus anterior (p.94)

named for Sawtooth edge

Origin	Ribs 1-8, and fascial covering of the intercostal muscles.
Insertion	Anterior surface of the vertebral border of the scapula.
Primary Actions	Protraction of the shoulder (scapula abduction).
Other Actions	Upward rotation of the scapula. Only the scapula can perform upward rotation.
Comments	Boxer's muscle.

Scapular Retraction

Rhomboids (p.90-91)

Two separate muscles, rhomboid major & minor but we'll tream 'em as one. angled downward, so two actions.

Origin	Spinous processes of C7-T5
Insertion	Medial border of scapula from the spine to the inferior angle.
Primary Actions	Shoulder retraction (scapula adduction) and scapular elevation.
Other Actions	downward rotation of the scapula.
Comments	Serratus & rhomboids are antagonists.

Trapezius: middle portion (p.76-78)

Trapezius is on the back and is named for the geometrical shape of both of them viewed together. It is a single muscle but we will consider it in three pieces.

Origin	Spinous processes of C7-T6
Insertion	Medial portion of the acromion process and the most lateral aspect of the spine of the scapula.
Primary Actions	Scapula adduction; Shoulder retraction.
Other Actions	None
Comments	Superficial to supraspinatus. Rhomboids and Middle traps are agonsists and synergists.

Scapular Elevation

Trapezius: upper portion (p.77-78)

Origin	Occipital bone and the nuchal ligament associated with the spinous processes of C2-C7. (Found by flexing the neck and feeling from Occipital protruberance.
Insertion	Lateral third of the clavicle and a small portion of the medial acromion process.
Primary Actions	Extension of the head and neck; elevation of the scapula; lateral flexion of the head and neck; contra
Other Actions	Upward rotation of the scapula. (you can sweep these under the rug).
Comments	Muscle that elevates has to be superior to the bone it's elevating. Contralateral (opposite side). Faces turns to the opposite side of where the muscle is.

Levator scapulae (p.91-93)

named because it elevates the scapula

Origin	Transverse processes of C1-C4 (4 connections)
Insertion	Medial aspect of the superior angle of the scapula.
Primary Actions	Elevation of the scapula extension of the head and neck
Other Actions	Lateral flexion of the head and neck Ipsilateral rotation of the head and neck
Comments

Scapular Depression

Trapezius: lower portion (p.77-78)

Origin	Spinous processes of T6-T12
Insertion	Medial 1/3 of the spine of the scapula
Primary Actions	Depression of the scapula shoulder retraction (adduction of the scapula)
Other Actions	Upward rotation of the scapula
Comments	Upward and downard rotation is defined based upon what the glenoid cavity does.

Pectoralis minor (p. 100-101)

Origin	Medial aspect of the coracoid process of the scapula
Insertion	Near the costal cartilages of the 3rd through 5th ribs and sometimes from the 2nd rib as well.
Primary Actions	Depression & protraction of the scapula (abduction)
Other Actions	Elevation of the ribs
Comments	Named because it's in the pectoral region of the body. Can flip the origin and insertion for this muscle based on which muscle stays stationary.

Head and Neck

Head flexion

Sternocleidomastoid (p.250-251)

Origin	Manubrium of sternum, medial 1/3 of the clavicle
Insertion	Mastoid process of the temporal bone and the lateral half of the superior nuchal line of the occiput
Primary Actions	Flexion of the head, lateral flexion of the head. [ALL THE NECK MUSCLES WE STUDY DO LATERAL FLEXION]
Other Actions	Contralateral rotation of the head.
Comments	SCM commonly traumatized in hyperextension injuries such as whiplash. TrP in the SCM reflex pain into the face, teeth, and over the eye and eyebrow. Torticolis will be on the national exam; 'rye neck' SCM issue.

Scalenes (p.252-255)

Origin	Transverse processes of C2-C7
Insertion	First and second ribs
Primary Actions	Flexion of the neck Elevation of the 1st and 2nd ribs
Other Actions	Lateral flexion of the neck
Comments

Semispinalis capitis (p.207)

Origin	Transverse processes of T1-T6
Insertion	Spinous processes of C2-C5 and up to the occiput
Primary Actions	Extension of the neck Contralateral rotation of neck
Other Actions	Lateral flexion of the neck
Comments	The muscles CURVE medially into the spinous processes. Vertical muscle fibers that curve are at an angle and thus rotate.

Splenius capitis (p.209-210)

Looks like an elastic bandage (splenius is latin for bandage)

Origin	Spinous processes of C7-T3
Insertion	Mastoid process
Primary Actions	Extension of the neck, ipsilateral rotation of the head
Other Actions	Lateral flexion of the head
Comments	Sustained neck flexion (reading at a desk, head turned over) can make these dysfunctional.

Disclaimer: These are MY notes taken from classroom lectures while I'm in the classroom. While I'm perfectly happy to share my notes with my classmates and I know I take very good notes, you should still make every effort to attend the class and TAKE YOUR OWN NOTES. I will not transcribe everything the instructor says in the classroom, and I will NEVER post pre-exam reviews. My notes will not replace the value of actually attending class and taking your own class notes.I also cannot attest to their accuracy, other than they are what was provided in the lecture; you should not reference my notes as "expert opionion" by any means, and if you notice an error or omission, please do me the favor of e-mailing me with the correction and I will re-post my notes. End of Disclaimer.